Cen8) from the African cultivated rice (O. glaberrima) and two subspecies of the Asian cultivated rice (O. sativa), indica and japonica. We detected much higher transposon contents (>69%) in centromere regions than in the whole genomes of O. sativa ssp. japonica and O. glaberrima (~35%). We compared the three Cen8s and identified numerous recent insertions of transposons that were frequently organized into multiple-layer nested blocks, similar to nested transposons in maize. Except for the Hopi retrotransposon, all LTR retrotransposons were shared but exhibit different abundances amongst the three Cen8s. Even though a majority of the transposons were located in intergenic regions, some gene-related transposons were found and may be involved in gene diversification. Chromatin immunoprecipitated (ChIP) data analysis revealed that 165 families from both Class I and Class II transposons were found in CENH3-associated chromatin sequences. These results indicate essential roles for transposons in centromeres and that the rapid divergence of the Cen8 sequences between the two cultivated rice species was primarily caused by recent transposon insertions.Centromeres are important chromosomal regions necessary for eukaryotic cell segregation and replication. Due to high amounts of tandem repeats and transposons, centromeres have been difficult to sequence in most multicellular organisms, thus their sequence structure and evolution are poorly understood. In this study, we analyzed transposons in the centromere 8 ( S. cerevisiae is comprised of a 125-bp DNA sequence, called a “point” centromere  in rice variety Nipponbare (O. sativa L. ssp. japonica) harbors only ~65-kilobases (kb) of tandem repeats , O. brachyantha and O. glaberrima were analyzed and colinearity and conservation of centromeric genes were observed in these orthologous centromeres -repeats, centromere 8 (Z. may) genome  from one location to another in genome. Transposon movement can result in mutations, alter gene expression, induce chromosome rearrangements and, due to increase in copy numbers, enlarge genome sizes. Thus, they are considered an important contributor for gene and genome evolution  and two subspecies of Asian cultivated rice (O. sativa), indica and japonica. We identified numerous recent transposon insertions, including some into centromeric genes, and found that the transposons were often organized into nested blocks. We also searched the ChIP cloning data and identified CENH3-associated transposons. Our results reveal the highly dynamic nature of transposons in the Cen8 region and suggest that transposons played a pivotal role in the rapid divergence of the Cen8 DNA sequences between these two cultivated rice species.To gain more insight into centromeric transposons and their role in centromere evolution, we analyzed the composition and organization of transposons in three orthologous Oryza species were used in this study, including Nipponbare , African cultivated rice  and six wild rice species: O. nivara (AA), O. longistaminata (AA), O. rufipogon (AA), O. punctata (BB), O. minuta (BBCC), and O. officinalis (CC). The seeds from all eight rice species were planted and grown in the greenhouse, and young leaves were collected to extract DNA using the cationic detergent cetyl-trimethylammonium bromide (CTAB) method.A total of eight Cen8 sequence of O. glaberrima was sequenced by the Evolutionary Genomics of a Rice Centromere Project , Fiber-FISH and PCR analyses. The Cen8 from Kasalath was obtained from the rice genome research program (RGP) website (http://rgp.dna.affrc.go.jp/E/Publicdata.html). The 2.4-Mb Cen8 of Nipponbare was downloaded from the GenBank and its boundary was determined based on the previous researches  are shown in Supplementary Figure The 1.3-Mb Cen8s, the rice transposon library  was incorporated with other published transposon databases . The program was run with default settings and “nolow” option to avoid masking the low complexity DNA or simple repeats. In addition, we also set a cutoff score greater than 300 and hit sequence larger than 50 bp in length. All reads obtained by RepeatMasker were inspected manually to (1) determine the exact boundaries of each element and their target site duplications (TSD), (2) remove the overlap regions which were annotated as different transposons, (3) determine the elements that were nested by other transposons or other copies of itself, and (4) count the copy number of transposons in Cen8 sequences.In order to annotate TEs in the Cen8 sequences from two cultivated rice species. The orthologous transposons were defined by a combination of three approaches: (1) structural futures of transposons including long terminal repeats (LTRs), terminal inverted repeats (TIRs), and target site duplications (TSDs); (2) sequence alignment; and (3) the centromeric genes flanking the TEs.To track transposon dynamics and to detect newly inserted transposons, we compared the https://www.sanger.ac.uk/resources/software/act). The three Cen8s were first used for all-against-all BLASTN searches with the -m 8 option between each other. The output files and the Cen8s were then used to generate sequence alignment with ACT using the default options.The sequence alignments were conducted using the Artemis Comparison Tool . The digested DNA fragments were separated by electrophoresis on a 1.0% (w/v) agarose gel at 55 v for 11 h and then transferred to a nylon membrane . The LTRs of three retrotransposons were used to design primers to amplify DNA from Nipponbare. The primers used were as follows: CRR1 ; RIRE3  and Hopi . The PCR products were labeled with [α−32P]-dCTP using the rediprime II random prime labeling system  according to the manufactures instructions. Blots were hybridized at 58.5°C for overnight and washed with 1.5× SSC solution for 30 min and 1× SSC for 30 min. The membrane was exposed on a Fuji-image plate and the hybridization signals were captured using a Fujifilm FLA-5100 multifunctional scanner.DNA hybridization was performed with 10 μg of total DNA digested with Cen8 sequences from Nipponbare  , however, the Class I transposons contributed much more sequence, 57.5% vs. 11.7%, due to larger average size of Class I elements. Ty3-gypsy elements were the most abundant LTR-retrotransposons contributing more than half of the Cen8 sequence. We detected DNA transposons from five superfamilies in the Cen8 including Mutator, hAT, CACTA, PIF/Harbinger, and Helitron  was highly conserved between rice, maize, and other grasses and likely plays important role for functional centromeres  and 409 to 129,488 bp , respectively. The TEs in nested blocks accounted for 37.2, 39.1, and 40.3% of the Cen8 in O. glaberrima, Nipponbare, and Kasalath, respectively. Interestingly, some TEs were involved in multi-layered nested blocks in which previous nested elements further served as hosts for additional TEs. For instance, we found a solo LTR of SZ61 that harbors two DNA transposons (Os1231 and Os3426) and 10 LTR retrotransposons that were organized into two to six-layer nested blocks in Nipponbare. The orthologous solo LTR also hosts 14 and 15 transposons in Kasalath and O. glaberrima, respectively . However, the numbers of DNA transposons that inserted into RNA and DNA elements were similar (19 vs. 17)  and 76.3% (71/93) of the total nested TEs were into the group of RNA into RNA, respectively.To determine if different TE classes exhibited insertion preferences, all nested transposons were divided into four groups based on host and nested transposons: RNA TEs inserted into RNA TEs, RNA TEs inserted into DNA TEs, DNA TEs inserted into RNA TEs and DNA TEs inserted into DNA TEs. Among 142 nested TEs (106 retrotransposons and 36 DNA transposons) in E-value < 1 × 10−5). Further investigation indicated that 60% of the 8,883,768 CENH3-associated chromatin sequences were related to LTR retrotransposons, and the other 40% of the reads shared significant sequence similarity to different superfamilies of DNA transposons, including Mutator, CACTA, hAT, Helitron, Harbinger, and Tc1/mariner .To detect if transposons can bind to the centromere-specific histone and to serve as component for centromere formation, the sequencing data obtained from chromatin immunoprecipitated DNA with an anti-CENH3 antibody in rice .Given that both Cen8s sequences consist of TEs, we wanted to determine if TEs were involved in the formation of centromeric genes. Based on the Rice Genome Annotation Project Data (http://rice.plantbiology.msu.edu), 106 genes that do not encode transposon proteins were found in the Cen8 of Nipponbare. We analyzed the 106 centromere genes and identified 28 that contain transposon-related sequences. A total of 53 transposon sequences were detected including 47 complete elements and five complete solo-LTRs. Further investigation indicated that 69.8% (37/53) of the transposons were located in introns of the genes, and another 30% served as coding DNA sequences (CDSs) or untranslated regions (UTRs)  Table . HoweverCen8s. All identified transposons in the Cen8s were manually inspected and their orthologs defined by sequence alignment of the transposons and flanking orthologous genes. Because some regions of Cen8s from both Kasalath and O. glaberrima were not sequenced, and a unique 66.5-Kb fragment in Cen8 of O. glaberrima had no orthologous sequence in the Nipponbare genome  in Nipponbare and 8.3% (33/400) in O. glaberrima, whereas, the rate between Cen8s of Kasalath and O. glaberrima was 21.6% (80/371) for Kasalath and 9.1% (29/320) for O. glaberrima, respectively. There was a higher transposition frequency in Cen8s of Nipponbare and Kasalath than in O. glaberrima—similar to the whole genomes comparison where more recent retrotranspositional activity was detected in the O. sativa lineage than in O. glaberrima  and common bean (P. vulgaris),  and centromere retrotransposon  which were completely different from that found in A. thaliana, 178-bp repeat pAa and ATHILA retroelement (Ty3-gypsy group)  related elements, in Cen8s from O. brachyantha and O. granulata shared no sequence similarity between the two wild rice species or to cultivated rice. Together, these data indicated that centromere repeats have undergone rapid replacement and that centromere repeats, including the canonical CRs, have been overtaken by new retrotransposons and/or removed from centromere regions. However, most of previous studies focused on characterization of centromere specific repeats in more distantly related plants—last sharing a common ancestors more than 10 million years ago—and did not provide detailed comparisons of entire centromeres.Although the function of centromere is highly conserved among eukaryotes, centromeric repeats evolved rapidly and show little or no sequence similarity even between related species , which replaces canonical histone H3 in the nucleosomes of functional centromeres, is highly conserved and can interact with all centromeric DNAs studied so far  of Nipponbare , much higher than in Chr3s with 2.3 blocks/Mb (45/19.4 Mb). These data indicated that the TEs in Cen8 exhibited higher density and more complex organization patterns than in euchromatic regions of rice, more similar to maize (Kronmiller and Wise, Nested organizations of LTR-retrotransposons has been frequently observed in genomes with high transposon densities (Kronmiller and Wise, ddm1 mutant of A. thaliana and most of the active TEs inserted in centromeric repeats (Tsukahara et al., Cen8s and appeared to have played an important role in reshaping these centromeres. The nested transposon blocks contribute more than half of centromere transposons in the Cen8s from both cultivated rice species, and we identified many unshared TEs in the nested blocks that both disrupt sequence colinearity and increase sequence centromere divergence, in short time period. Lastly, nested TEs provide useful information to study Cen8 evolution. Nested transposons offer valuable information to track the evolutionary history of transposons and to reconstruct ancient TE insertions relative to their “pre-nested” states (Kronmiller and Wise, Cen8s allowed us to identify the transposons that likely existed in the Cen8 region before the divergence of two cultivated rice species. We found a number of accession-specific transposons and that many insertions in the nested TEs were recent and greatly expanded the Cen8 sequences (Figures Nested organization of transposons may have important impacts on centromere evolution and on the host genome. First, TE insertions into transposons may be less harmful for host genome as transposons insertions can be harmful or lethal if inserted into important genes. Thus, the transposons frequently integrate into gene poor regions. For instance, massive transposition events were detected in the  Figures , 5.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


N = 112) completed Conners' Adult ADHD Rating Scales and letter matching reaction time tasks. In the tasks, participants had to match a single target letter displayed below the fixation cross, either on left or right visual field, with one of two letters displayed above the fixation cross, one letter on each visual field. For each task, identical letters were presented either within the same visual field (within hemisphere condition) or across visual fields (across hemisphere condition). Interhemispheric interaction was indexed as the difference in mean reaction time between within and across hemisphere conditions. Comorbid problems such as depression, anxiety, and stress may affect task performance and are controlled for in this study. Findings indicated that self-reported ADHD symptomology, especially hyperactivity, in the presence of stress was weakly but significantly associated with fast interhemispheric interaction.The present study applied the dimensional approach to test whether self-reported symptoms of Attention Deficit/Hyperactivity Disorder (ADHD) in adults are associated with the speed of interhemispheric interaction. A sample of first grade students ( A recent meta-analytic review indicates that childhood and adulthood Attention Deficit/Hyperactivity disorder (ADHD: DSM-IV) are characterized by compromised information processing skills including executive function demonstrated in reaction time studies . These cRecent meta-analytic reviews on the structure of the corpus callosum in patients with ADHD concluded that there is some evidence that its size is reduced; however, some potential confounders have to be taken into consideration such as a small sample size; some patients were on medication during the assessment. Moreover, most of the studies included patients with comorbid disorders such as oppositional defiant disorder and conduct disorder , 7. WithInconsistencies in findings might at least partly be caused by complex interactions between group factors such as age, IQ, gender, different types of comorbidities , handednThere are several reasons to prefer a dimensional approach above the categorical approach when studying the relation between speed of interhemispheric interaction and ADHD symptomatology. The dimensional approach does not require the arbitrary dichotomization of individuals into categories based on an all-or-none principle but positions individuals on a continuum . ConsequThe dimensionality of ADHD in adults has been studied on the basis of self-reports such as Conners' Adult ADHD Rating Scales (CAARS) , a populThe present study is the first to investigate the relation between self-reported ADHD symptomatology and interhemispheric interaction in an adult population. ADHD symptomatology was measured by the CAARS, because it provides scores on continuum dimensions rather than other ADHD questionnaires that classify individuals into two categories (having or having not ADHD). Interhemispheric interaction was measured using the Banich tasks –33. TherThe Banich paradigm consists of two conditions: a within hemisphere condition , and an across hemisphere condition . The paradigm is based on the fact that the utility of interhemispheric interaction varies with task complexity. Increasing task complexity guides the reaction time performance to benefit from the cooperation between the two hemispheres with a faster reaction time on an across hemisphere condition compared to a within hemisphere condition. Therefore, the paradigm has two tasks that differ in complexity level: a physical-identity task and a more complex name-identity task. In the physical-identity task only perceptual identification is required to reach a decision. Here, faster or equal reaction times are expected in the within hemisphere condition compared to the across hemisphere condition, whereas, in the name-identity task, additional computational steps beyond the perceptual identification  are required to reach a decision. In this case, the expectation is faster reaction times on across hemisphere condition compared to the within hemisphere condition indicating that faster interhemispheric interaction is required for complex information processing , 41–44.According to the Banich paradigm, there are two ways to measure interhemispheric interaction; the first is to calculate the difference in mean reaction time between within and across hemisphere task conditions. The second is to investigate reaction times for only the across hemisphere condition. The latter option is considered to be less accurate because processing delay is not controlling for left or right hemisphere deficits , 33. TheThe main research question is whether the key domains of the ADHD symptomatology included in the CAARS predict the speed of interhemispheric interaction. The study takes anxiety, depression, and stress into account since it is well-recognized that emotional state and mood symptoms are related to ADHD symptomatology, especially stress , 46 thatOne hundred thirty-four undergraduate psychology students reacted to an advertisement to join a laboratory experiment about interhemispheric interaction and ADHD symptoms. With an emphasis on ADHD symptoms in the advertisement we aimed to attract a larger than usual proportion of subjects with ADHD that would result in a sample with a wide range of ADHD symptoms from zero to full diagnosis. Based on the questionnaire information the following exclusion criteria were applied: (a) reported former diagnosis with ADHD and/or depression and/or anxiety but currently reporting few ADHD symptoms , (b) being under medication related to ADHD and/or mood disorders, and (c) self-reported left handedness.One hundred twelve subjects remained in the sample including 11 subjects with high scores on the ADHD index scale . Participants reported normal or corrected to normal vision. Using Edinburgh Handedness Inventory , it appeThe responsible ethical committee “Ethical Committee Psychology-University of Groningen” has approved the experiment with a research code “13008-NE.” The experiment was conducted with the understanding and the consent of the human subject. Written informed consent was obtained from all participants. Participants were informed that their responses will be kept strictly confidential and anonymous, and they have the option to withdraw from the study at any time, without penalty.The participants anonymously completed Conners' Adult ADHD Rating Scales (CAARS)  and the The DASS questionnaire is subdivided into three subscales: (a) depression; (b) anxiety; and (c) stress. Each subscale contains 14 items . The participants rated how often each emotional state applied to them over the last week on a four-point scale ranging from 0  to 3 (applied to me very much). The sum score of each subscale classifies the participants into one of five categories .The CAARS and DASS questionnaires have a high reliability and validity and are suited for the dimensional approach on psychopathology , 23, 57.A single target letter, displayed on the left or on the right visual field below the fixation cross, had to be matched with one of two probe letters displayed laterally above the fixation cross. In the physical-identity task, all letters were displayed in upper-case and a match was defined in terms of physical-identity. In the name-identity task, the target letter was displayed in lower-case and the probe letters were displayed in upper-case, and a match was defined in terms of name-identity. Each task consisted of 80 trials; match and mismatch ratio was 50 : 50. Mismatch trials were included to prevent impulsive and careless responding. For match trials, half were within hemisphere trials in which matching letters were presented within the same visual field . The other half of the match trials were across hemisphere trials in which matching letters were presented across visual fields . Each trial started with a black slide with a fixation cross presented for 1000 ms. Thereafter, three letters were presented along with the fixation cross for 150 ms. Next, a black slide with a fixation cross was assigned for participant's response for 2000 ms. Finally, a blank black slide was presented for 500 ms indicating the end of the trial.In the physical- and the name-identity task, letters were presented in upper- and lower-case from A, B, D, G, H, E, F, L, R, M, T, and Q. They were arranged in triangular position: Two different probe letters were presented 1.6° above the fixation cross, one on each visual field, 2.68° to the left or right of the midline, and the target letter was displayed 1.6° below the fixation cross, 1.6° to the left or right of the midline. The fixation cross was always located in the center of the screen during the trial. All letters had the same dimensions of 0.95° horizontally and 1.3° vertically presented in white color on a black background (to reduce the light emitted from LED screen).The tasks were conducted on a laptop computer using E-Prime software version 2.0 to control the stimulus presentation and to specify the correct responses. The letters were displayed on LED-backlit HD antiglare screen with 1024 × 768 pixel resolution and refresh rate of 60 Hz. A chin rest was used to fix the distance of 50 cm between the screen and participant's eye. A response box was used to record reaction times and correct responses. The box was positioned halfway between the chin rest and the screen to enable easy reach.Participants filled in the paper-and-pencil questionnaires and performed Banich letter matching tasks in a counterbalanced order. To perform the tasks, the participants seated in a dimly lit room, their chin rested upon the chin rest. They were instructed to press a key as fast as possible when a match appeared and not to respond during a mismatch trial. In addition, the participants were instructed to gaze at the fixation cross on the laptop screen all the time and not to move their eyes away when the stimuli appeared. For eye saccades, participants had to make the anticipated saccades after key pressing. Before each task, a practice block of trials was given until a criterion was met of seven correct responses in ten consecutive trials. After reaching this criterion, the practice block automatically terminated.To test whether we replicate performance findings of the Banich paradigm, a repeated measures analysis of variance was performed on mean reaction times (RTs) of the correct responses. For the physical- and the more complex name-identity task, the index of interhemispheric interaction speed was individually calculated as the difference in mean RTs between within and across hemisphere trials: [(Within RT − Across RT)/overall mean RT]. Please note that a higher value reflects faster interhemispheric interaction. According to the Banich paradigm, if the task is more complex faster interhemispheric interaction is required for an optimal performance.To determine which ADHD and mood symptoms predict the speed of interhemispheric interaction multivariable linear regression analyses were performed. Finally, groups with high and low levels of symptomatology (first and third tertile scores) were compared on the interhemispheric interaction index using a repeated measures analysis of variance.To save space Like the CAARS, also the DASS is a quantitative measure with cut-off scores to characterize degree of severity relative to the population. The large majority of the sample scored within the normal range on severity  of mood symptoms; about 15% of the sample had high mood symptoms see .r = 0.57, p < 0.001 for depression, r = 0.37, p < 0.001 for anxiety, and r = 0.50, p < 0.001 for stress indicating a moderate overlap of ADHD and mood symptomatologies.Pearson correlations between the overall ADHD symptomatology (ADHD index) and mood symptoms were Less than 5% errors were made; therefore, number of errors has not been taken into consideration. The reaction time analyses were run with and without the 15 subjects with inconsistent responding on the CAARS and run with and without the seven participants with mixed handedness. The outcomes did not essentially differ. Thus, data analyses on 112 subjects are presented below.r = 0.17, p = 0.07). The finding indicates the higher the ADHD index score, the slower the RT performance. This was especially the case in the name-identity task  and more specifically for within hemisphere trials .Pearson correlations were calculated between the overall mean RT  and the ADHD index, inattention, hyperactivity, impulsivity, depression, anxiety, and stress. Only the ADHD index showed a positive trend with the overall mean RT (p ≥ 0.27). Therefore, we collapsed the mean RTs for males and females together  and trial type . The analysis revealed a significant main effect of task, F  = 421.01, p < 0.001, η2p = 0.79, with faster RTs in the physical-identity task (M = 593) than the name-identity task (M = 743). According to the Banich paradigm, the interaction between trial type and task must be significant. This was the case in our data set: the interaction was F  = 40.96, p < 0.001, η2p = 0.27; the RTs in the name-identity task were faster on across hemisphere trials (M = 721) compared to within hemisphere trials (M = 766), while RTs in the physical-identity task were equal for within hemisphere (M = 592) and across hemisphere trials (M = 593).To investigate whether our reaction time data could be interpreted in terms of the Banich paradigm, a repeated measures analysis of variance was carried out on reaction time performance. The within subjects factors wereW = 0.98, p = 0.08 for the physical-identity task and W = 0.99, p = 0.71 for the name-identity task).The left and right panels of R2 ≤ 0.03, p ≥ 0.36). In the second, the three key domains of ADHD  were the independent variables. The results revealed nonsignificant predictors . Consequently, the ADHD symptomatology in isolation from mood symptomatology has no association with interhemispheric interaction. The picture becomes different when exploring the combination of both symptomatologies. Tables The interhemispheric interaction speed indices for both tasks were used as dependent variables in two multivariable linear regression analyses. In the first, the ADHD index was the independent variable. The results indicated that the ADHD index was not a predictor  and in the group with low stress  apart. In the group with high stress, faster interhemispheric interaction was correlated with higher scores on the ADHD index  and the hyperactivity subscale . In the group with low stress correlations were not significant with p values ≥0.39.To explore in detail the effect of stress on ADHD symptoms and the speed of interhemispheric interaction, Pearson correlations were calculated between the ADHD index, hyperactivity scores, and the interhemispheric interaction index of the name-identity task in the group with high stress  and a between subjects factor of group  indicated that group composition based on the ADHD index, inattention, and impulsivity subscales revealed no group differences. However, the high-score group on the hyperactivity subscale showed overall faster interhemispheric interaction than the low-score group; the main effect of group was significant F  = 3.95, p < 0.05, η2p = 0.06. Post hoc analysis for the hyperactivity subscale indicated that the groups differed in the name-identity task, t (74) = −2.17, p < 0.03, but not in the physical-identity task; the mean interhemispheric interaction indices were 0.046 and 0.086 in the name-identity task, and they were −0.006 and 0.010 in the physical-identity task for, respectively, the low- and the high-score group.Finally, to test the ADHD-interhemispheric interaction link more thoroughly we compared the speed of the interhemispheric interaction of first and third tertile groups on the ADHD index, inattention, hyperactivity, and impulsivity subscales of the CAARS. Repeated measures analyses of variance with a within subject factor ofThe present study is, to the best of our knowledge, the first to use the dimensional approach to investigate the relation between interhemispheric interaction and ADHD symptomatology. In many ways, the participating sample is more homogenous compared to samples of clinical studies on this subject with respect to factors such as age and IQ. Known mood comorbidities have been controlled for. Other potentially relevant comorbidities related to ADHD such as learning and conduct disorders are supposed to be absent in the participating university student sample.The task used may be considered a valid and reliable instrument to estimate interhemispheric interaction. First, as expected from the Banich paradigm, the more complex name-identity task needed more information processing resources resulting in slower reaction times compared to the less complex physical-identity task. Second, across hemisphere advantage was found in the name-identity task indicating that the performance benefits from interhemispheric interaction when tasks are more complex. Consequently, the two performance findings were in accordance with literature.The main conclusion was that ADHD symptomatology, especially hyperactivity, together with stress contributes weakly but significantly to the speed of interhemispheric interaction, at least as far as visual information processing is concerned suggesting that callosal splenium  functioIt might be surprising that only hyperactivity was playing a role in our study, not the other symptoms, because longitudinal studies have indicated that hyperactivity decreases whereas inattention, impulsivity increase as a function of age . One posThe fact that stress plays a crucial role in the dimensional relationship between ADHD symptoms and interhemispheric communication gives further support to the idea that ADHD is a stress-related disorder which might be one of the important causes of ADHD . Please The present findings indicate that ADHD symptomatology is related to slower mean RT and that the ADHD symptomatology in the presence of stress is linked to faster interhemispheric interaction. At first sight, faster interhemispheric interactions could be interpreted in positive terms. This would be the case if fast interhemispheric interaction is linked to fast performance. However, in our sample RT performance of subjects with higher level of ADHD symptoms did not benefit from fast interhemispheric interaction: they were overall slower. Our findings suggest that optimal performance requires a specific range of interhemispheric interaction speed and that too fast or too slow interhemispheric interaction may negatively affect or interfere with performance. Within the Banich paradigm, the optimal range of interhemispheric interaction may vary as a function of the level of task complexity. Consequently, our findings justify suggesting that ADHD symptomatology is linked with fast but nonoptimal interhemispheric interaction. The finding that ADHD symptomatology is related to faster interhemispheric interaction is in line with clinical studies –10, but The first limitation of the present study could have been the lack of eye-gaze verification. Central fixation was encouraged and participants were instructed to make eye saccades after key pressing. Nevertheless, it is possible that participants' gaze was not directed to the central fixation cross on every trial. We have to admit that these variations in gaze could have influenced performance. However, given the low error percentage together with fast stimulus presentation (150 ms), it seems unlikely that variations in gaze confounded our results.A second limitation is that the university students are not representative with the adult population in general. In addition, the present sample includes more females than males. As a result, the present outcome needs replication for adults in general and should also examine samples with more equal sex distribution. Having this said, the CAARS scores are corrected for gender and the reaction time data showed no difference between male and female students. It is well-recognized that the validity of self-reports from students may be questioned. For instance, one should be suspicious if students rate themselves as being significantly symptomatic yet have managed to achieve well in school and in other life activities, especially, if their T-scores were above 80 . Please A third limitation is that our data apply only to right-handers. The relation between ADHD symptoms and interhemispheric interaction remains unexplored in inconsistent- and left-handers; this calls for future studies on inconsistent-handers specifically as it has been reported that inconsistent handedness is associated with increased interhemispheric interaction  and ADHDThe present study focused on integrating visual information processing . It is recommended to direct future research towards the anterior part of the corpus callosum connecting the frontal and prefrontal cortex . This structure subserves higher order cognition such as executive function and its possible interactions with self-regulation and effort which are assumed to be compromised in ADHD –68.Our dimensional findings indicated that ADHD symptomology, especially hyperactivity, in the presence of stress was weakly but significantly associated with fast interhemispheric interaction. These findings are supporting studies on clinical samples.


Introduction: The effective development of reading and writing skills requires the concerted action of several abilities, one of which is phonological processing. One of the main components of phonological processing is rapid automatized naming (RAN)—the ability to identify and recognize a given item by the activation and concomitant articulation of its name.Objective: To assess the RAN performance of schoolchildren with dyslexia and attention deficit hyperactivity disorder (ADHD) compared with their peers.Methods: In total, 70 schoolchildren aged between 8 and 11 years participated in the study. Of these, 16 children had a multiprofessional diagnosis of ADHD while 14 were diagnosed with dyslexia. Matched with these groups, 40 schoolchildren with no history of developmental impairments were also evaluated. The RAN test was administered to assess the length of time required to name a series of familiar visual stimuli. The statistical analysis was conducted using measures of descriptive statistics and the 2-sample t-test at the 5% significance level.Results: The performance of the group with dyslexia was inferior to that of the control group in all tasks and the ADHD group had inferior performance for color and letters-naming tasks. The schoolchildren with dyslexia and those with ADHD showed very similar response times. Age was an important variable to be analyzed separately. As they aged, children with typical language development had fast answers on colors and digits tasks while children with dyslexia or ADHD did not show improvement with age.Conclusions: The schoolchildren with dyslexia took longer to complete all tasks and ADHD took longer to complete digits and objects tasks in comparison to their peers with typical development. This ability tended to improve with age, which was not the case, however, with schoolchildren who had ADHD or dyslexia. The Rapid Automatized Naming (RAN) test has its importance and relevance traced from nineteenth century  compared with individuals with dyslexia and their typically developing peers, specifically with regard to their phonological processing abilities. However, RAN tends to be different in predicting dyslexia for each language. For example, all RAN tasks are reported to be slower for American children with dyslexia  and Centro Universitário Metodista Izabela Hendrix (Protocol No. 214/2008). Both committees gave ethics clearance for conducting this research with humans.The present study was approved by the institutional review boards of In total, 70 schoolchildren aged between 8 years 2 months and 11 years 1 month participated in the study: 40 children without complaints of language, hearing, or learning disabilities, 16 children with a multiprofessional diagnosis of ADHD, and 14 children with a multiprofessional diagnosis of dyslexia. All children in the study came from public schools in the same city. The ADHD group comprised 12 boys and 2 girls while the dyslexia group comprised 11 boys and 3 girls  students who read well, (b) students who read reasonably well, and (c) students who read poorly.Based on that rating list, the children categorized as good readers were selected to compose the final sample of 40 students without complaints of oral and written language impairments.The inclusion criteria were as follows: (1) the children should be regularly enrolled in a public school between second and fifth grade of elementary school; (2) written informed consent should be provided by the children's parents or legal guardians; and (3) the children should not have any health condition that could, directly or indirectly, affect the language development status as indicated by the questionnaire completed by the parents. Children were excluded if their parents or legal guardians did not provide written informed consent or if their parents or legal guardians reported the presence of any pathological condition unrelated to the language disabilities reported in the questionnaire.Although the testing was performed in different locations (school and clinic), the researchers were careful to choose a silent and private room to test the control group.Laboratório de Estudo dos Transtornos de Aprendizagem—LETRA (Learning Disorders Study Laboratory) of UFMG Hospital das Clínicas. All the children were evaluated by a neurologist, a psychologist, a speech-language pathologist, and audiologist, an occupational therapist, and an educationist, who jointly made the clinical diagnosis of dyslexia and ADHD based on the objective assessments conducted. It is worth emphasizing that none of these children had undergone any speech-language therapeutic intervention.All 30 schoolchildren diagnosed with dyslexia and ADHD were given a multiprofessional clinical diagnosis by the team of The assessments conducted by the team comprised a focused history, standard neurological examination (ENT), evolutional neurological examination (ENE) Rotta, , ChrysleThe sample inclusion criteria were as follows: (1) children aged 8–11 years; (2) regularly enrolled in Minas Gerais public schools; (3) diagnosed with dyslexia or ADHD as verified by the LETRA team; (4) no co-occurring pathological condition of any origin; and (5) with written informed consent provided by the parents or legal guardians. Age was not treated as co-variant at first due to the small sample of participants on the clinical group. Children were excluded if they (1) failed to provide written informed consent signed by the parents or legal guardians; (2) were outside of the study age range, or (3) had a co-occurring pathological condition with dyslexia or ADHD.The RAN test  had sufficient numbers of schoolchildren to allow the analysis by age ranges, considering that no statistically significant differences were found between the experimental groups. The allocation for the analysis by age ranges was as follows:p < 0.05) for all groups. To examine if dyslexia and ADHD could be analyzed together or independently to study age influences we conducted 2-sample t-test comparing directly children with dyslexia and ADHD. The matched children with vs. without the disorders were compared by two tailed student's t-test for independent samples (p < 0.05).Statistical analysis was performed with measures of descriptive statistics . Data were reviewed for normal distribution using Aderson-Darling statistics , and coefficients of variation were compared across groups. The performance of the groups in the RAN tasks is summarized in Table An overall comparison of the four groups showed that the letter-naming task was performed in less time than the other tasks by all groups, followed by the digit-naming task. The color and object-naming tasks took longer to be completed across groups.p-values, and probability plots for all RAN tasks are displayed in Figures To better understand these results, median values with the first and third quartile were measured in each task across groups, as shown in Figure Probability plot of colors shows that control group was faster in answering than dyslexia and ADHD groups Figure . On the p-value close to (1); (b) control group tend to be faster to respond RAN tasks; (c) dyslexia and ADHD have similar mean and, consequently, closer probability plot.Figures t-test comparing directly children with and without dyslexia (control vs. dyslexia), children with and without ADHD (control vs. ADHD), and children with dyslexia and ADHD  to study age influence. To examine that it was conducted a 2-sample HD Table . With thWhen comparing the control group with the two pathological groups separately, significant differences were noted for nearly all sub-items tested, with the exception of the colors and letters and naming skill for ADHD. The comparison between the pathological groups yielded non-significant differences.The means and SDs for the control and experimental (dyslexia or ADHD) groups separated by age range (8–9 years and 10–11 years) and the between-group comparisons are given in Table Age has shown to be an important variable to be analyzed separately. The mainly trends observed were: (a) as they aged, children with typical language development had faster answers on colors and digits tasks; (b) children with dyslexia or ADHD did not show improvement with age; (c) experimental and control group had statistic difference in all tasks for the younger groups; (d) experimental and control group had statistic differences in colors and digits tasks for the older groups.Both in the control and the experimental group, there was a trend toward improved task performance, with naming becoming faster with age. However, this improvement is much more evident in the control group, with a statistically significant difference between age ranges for color and digits tasks. By contrast, this difference, albeit observed in Figure The objective of the present study was to determine whether there is a significant difference in RAN performance between schoolchildren with ADHD and with dyslexia compared with their peers with no reading and writing development deficits, as well as understanding how the development of this skill happens with age and what are the main predictors of developmental disorders.All groups performed the letter and digit naming tasks faster and easier than they did with colors and objects. The naming of objects was shown to be significantly slower, followed by colors, which corroborates studies previously conducted , we assume that the testing environments could have affected the results.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


Behavioral and Brain Functions.It has been 10 years since Terje Sagvolden founded After setting the context, this paper reviews some of the contributions of articles in the journal to the literature on ADHD over that decade. Those articles provide a cross section of some of the most important ongoing themes in ADHD research.Terje’s faith in the new journal was well founded. It has survived the first threat of new journals, crib death, because of the continuing quality and relevance of the articles it carries. It has a diversified portfolio of similar research in many other fields of related interest. Myth pictures the Vikings as raiders and barbarians. During the three centuries of their northern dominance, however, the majority of the Norsemen’s energy was spent as traders and settlers, connecting cultures from Newfoundland to Russia, from Iceland to Marseilles and Pisa. For this they crafted their trademark vehicle, the longboat.Institute for Advanced Study where he spent a year with a cadre of researchers working on ADHD; the second was his trademark vehicle, the journal Behavioral and Brain Functions (BBF).Terje Sagvolden was a Norwegian who grew up near a recovered Viking longboat and a restored Viking village around Oslo. Like his forbearers he had an itch to travel, starting with a post-doc in America with Charles Catania, where he came to appreciate the power of behavioral analyses. In the early years of this century he became interested in attention deficit-hyperactivity disorder (ADHD), and began to study it from a behavioral perspective. To do this effectively he realized he would need a vehicle, and he crafted two of them. The first was a niche in an Oslo mansion that housed the I was a fellow at the institute thanks to Terje’s enterprise, along with many experts who voyaged from spots on the globe far beyond the ken of the Vikings. This was the year that Terje founded BBF, and I remember him accosting me, with his irrepressible enthusiasm, about this new journal, its goals, name, logo and aspirations. The journal has lived up to the aspirations, even though like most adventurers, Terje did not live to see the enduring success of his foundling. Nor did he see how this journal, dedicated to research which “provides insight on the neurobiological mechanisms underlying behavior and brain function and dysfunction”, would attract a much broader field of investigations than on just ADHD. It did that from the start, with almost half of the articles concerned with ADHD in the first 2 years, decreasing to a quarter in recent years, even while the total number published over that time has more than doubled. These articles have contributed importantly to our understanding of ADHD. Here are a few of the highlights of that subset of articles, chronologically encountered.The administration of low oral doses of methylphenidate (MPH) to rats affects pre-frontal cortical functions in ways similar to the effects seen in humans, both typically-developing and those with ADHD . This siIt is not only decision-making that is impaired in ADHD. The cerebellum, which, among its many functions, controls fine motor skills, is differentially affected in ADHD. Therefore motor skills should be impaired. In an adventurous study of seven ethnic groups in Africa, Meyer and Sagvolden  showed sConduct disorder is a frequent sequela of ADHD, and Beaver and colleagues  found thdynamic developmental theory—assumed aberrant reinforcement processes to be an important underlying endophenotype of that condition. Recent research [An important theory of ADHD—the research  providesresearch ; so eat research  one of td-amphetamine. In a randomized double-blind placebo-controlled crossover study, Wigal and associates [d-amphetamine.Animal models played a very large role in the genesis of the dynamic developmental theory, as they do for research on neurobehavioral disorders in general. But what is an animal model? Anyone contemplating such research, either as consumers or creators of it, should first read the article by van der Staay and colleagues , who laysociates  showed iAnother theory of ADHD is that it is all about inhibition failure. McLoughlin and associates  provide Early trauma, as fetus or child, is one of the important causal factors in the genesis of ADHD. Sterley and colleagues  found thAn important criterion for animal models is that they respond in ways similar to the human presentations for which they serve as model, both in behavioral tests and in response to relevant drugs. There has been ambiguity in the literature on the effects of methylphenidate (MPH) on rat models such as SHR. Cao and colleagues  provide The above highlights reflect both my own interests, and also my criterion that most of the articles mentioned have accrued more than ten citations per year every year since they went to press. This is an estimable record, and speaks to the hard work of the editors and reviewers in maintaining the quality that Terje set as a standard. BBF is the name of a longboat that plies the ether, carrying ideas and techniques to every part of the globe. It brings an impressive range of articles, ones involving clinically sophisticated analyses of comorbidities, executive functions, and endophenotypes; and methodologies including genetics, neuroimaging, neuropharmacology; and animal models, across species and across lifespans, on topics of current interest to the field. It enriches not only the lives of those who trade with it, but all in the larger world whose lives they improve with their work.


Attention-deficit/hyperactivity disorder (ADHD) is a highly prevalent psychiatric disorder in children/adolescents. This study reviews available European-based studies of ADHD-related costs and applies the findings to the Netherlands to estimate annual national costs for children/adolescents from a societal perspective. A systematic literature search was conducted for primary studies in Europe, published January 1, 1990 through April 23, 2013. Per-person cost estimates were converted to 2012 Euros and used to estimate annual national ADHD-related costs based on the Dutch 2011 census, ADHD prevalence rates, family composition, and employment rates. Seven studies met the inclusion criteria. The average total ADHD-related costs ranged from €9,860 to €14,483 per patient and annual national costs were between €1,041 and €1,529 million (M). The largest cost category was education (€648 M), representing 62 and 42 % of the low- and high-value overall national estimates, respectively. By comparison, ADHD patient healthcare costs ranged between €84 M (8 %) and €377 M (25 %), and social services costs were €4.3 M (0.3–0.4 %). While the majority of the costs were incurred by ADHD patients themselves, €161 M (11–15 %) was healthcare costs to family members that were attributable to having an ADHD child/adolescent. In addition, productivity losses of family members were €143–€339 M (14–22 %). Despite uncertainties because of the small number of studies identified and the wide range in the national cost estimates, our results suggest that ADHD imposes a significant economic burden on multiple public sectors in Europe. The limited number of European-based studies examining the economic burden of ADHD highlights the need for more research in this area.The online version of this article (doi:10.1007/s00787-013-0477-8) contains supplementary material, which is available to authorized users. The burden of psychiatric disorders in developed countries is large, representing up to 40 % of all brain diseases  and 14 % of all diseases . A recenADHD is a chronic behavioural disorder with onset in childhood that often persists into adulthood , 46. It Impairments associated with ADHD are multi-faceted, with outcomes such as academic failure, self-esteem problems, and interpersonal relationship difficulties , 57, 60.Children and adolescents with ADHD consume more healthcare resources and consequently incur more healthcare costs compared to those without ADHD , 27, 47.Similar cost-of-illness studies are scarce in Europe, and there is a lack of understanding of the economic burden of ADHD in Europe. The purpose of this study is to review the available evidence and to apply the findings to quantify the societal economic burden of ADHD in a European setting, using the Netherlands as a reference case. The focus of the present study is on the costs of ADHD in children and adolescents because there were no studies on adult ADHD-related costs identified.A systematic review was conducted using guidelines from the Cochrane Handbook for Systematic Reviews of Interventions . Five laThe screening process is outlined in Fig. Some calculations and/or adjustments of the data reported in the studies were required to align the information presented in the papers to our framework. From the Wehmeier et al.  study, tAll cost estimates reported in foreign currencies were converted to Euros for the matching year using gross domestic product per capita purchasing power parity provided by the Organisation for Economic Co-operation and Development . These eCosting data were drawn from all European studies meeting our inclusion criteria. From the included studies, per-patient cost estimates were used to calculate national ADHD-related costs for the Netherlands, the European reference country for this study. This study did not assess or adjust for differential study quality or characteristics beyond those specified in the inclusion criteria , including inherent statistical limitations of studies with a small sample size. As a result, point estimates for national costs were not calculated but instead the lowest and highest per-patient cost categories for each subcategory were identified (when more than one data source was available) and then used to estimate a total national ADHD-related cost range.The number of children and adolescents aged 7–17 years with ADHD in the Netherlands was estimated by multiplying the 2011 Dutch census estimates for this age group with the estimated prevalence of ADHD in the Netherlands. The only published ADHD prevalence estimate (2.1 %) for the Netherlands, however, is limited to prevalence of pharmacologically treated children and adolescents with ADHD . Data frThe estimation of the number of family members incurring costs related to ADHD required additional multiplication factors to determine the population size incurring the costs. Because the costs of healthcare and productivity losses to family members of patients with ADHD were applicable to adult members and not to other siblings of similar age in our analysis, a multiplication factor representing the average number of adults in households with children in the Netherlands was needed. This adult member multiplication factor was estimated to be 2.26 and was derived from the reports ‘SF1.1 Family Size and Composition’  and ‘SF1For each cost category, the low and high per-patient cost estimates were used to establish an annual national cost range for that category. For some categories such as healthcare costs to family members or education and social services costs to patients with ADHD, however, only one estimate was available. In these cases, the same estimate was used to calculate the low and high values in the range of total national costs. While there were two studies that investigated costs of education for patients with ADHD, these studies reported different aspects of education costs , 55. De The methods described above are for the base-case analysis. In economic modelling, the base-case represents the most likely assumptions on model structure and/or input parameters/data. Sensitivity analyses are also recommended to evaluate the robustness of the results as well as to assess different relevant scenarios. Thus, in addition to the base-case analysis, three sensitivity analyses were performed to vary key parameters in our base-case analysis. In the first scenario, the ADHD prevalence rate (4.8 %) was changed to the diagnosed and treated prevalence rate (2.1 %) for the Netherlands .The second scenario included a study by Petrou et al. , which dThe last scenario included a study by Knapp et al.  that invFrom an initial yield of 6,202 citations, a primary review of the titles, type of articles, and remaining duplicates excluded 4,637 studies Fig. . Upon a Five cost categories, for which costing data were available, were identified. Three categories were costs attributable to the child/adolescent with ADHD themselves  and two were costs to family members that were due to ADHD-related activities of a child/adolescent with ADHD . A list of the cost components that were described in each of the studies is provided in Supplementary Table 2. A summary of per-patient and per-family member cost estimates for each study is presented in Table The low and high estimates from each cost category were used to derive a range for total annual national ADHD-related costs for the Netherlands Table . Annual Total annual per-patient costs were calculated from the total annual national costs because the applicable population is not the same across the different cost categories. National costs to family members were divided by the ADHD patient population to estimate the costs to family members per ADHD patient instead of costs per family member as reported in the included studies. For example, annual ADHD-related costs of healthcare for the patients and the family members ranged from €2,322 to €5,095 per ADHD patient  of the overall national ADHD-related costs in the Netherlands. The observation that the majority of the ADHD-related costs was outside of the healthcare sector has important policy-making implications given the social insurance systems in Europe . In EuroWhile healthcare is not the major cost driver of ADHD, it is the most investigated cost category. With the exception of patient education and productivity loss to family members, which were each included in two studies, the other cost categories were investigated by just a single study. The scarce evidence on ADHD-related costs other than healthcare highlights the need for more cost research in education, social services, and the financial impact of productivity loss by family members of children and adolescents with ADHD. This literature review also identified costs to the justice system, substance abuse treatment, and traffic accidents as areas that have been suggested to be negatively impacted by ADHD but for which no cost-of-illness studies are presently available in Europe. Furthermore, there is a complete lack of studies investigating cost of ADHD in adult patients in Europe, even though this cost category may represent the majority of the total cost, as in the US .The major limitation of the study was the small number of studies that were included in the analysis. Moreover, included studies did not report the same cost categories. As a result, most cost categories, other than healthcare costs, were reported by only one or two studies. This further limited the available evidence on overall costs of ADHD, which increased the uncertainties around the annual national cost estimates. Given the limited data, a point estimate for annual national cost was not provided, because high variance between studies was expected. Instead, low and high values for each cost category, when possible, were used to estimate a range for the annual national cost. Compounding of error was a concern also, especially considering the small sample of studies and extrapolation to large monetary values.In addition to the small number of studies, there were other potential sources of bias. For instance, the seven included studies were from five different countries of the EU. Only one study was based in the Netherlands; of the remaining studies, three came from Germany and one each from Belgium, Sweden, and the UK. While all of these studies meeting the inclusion criteria were coincidentally based in northern/western countries of Europe, which share similar social-economic characteristics and cultural views on the treatment of ADHD, applying between-country cost estimates to the Netherlands may introduce bias given the differences in the healthcare, education, and social support systems across these countries. Whether this issue results in under- or over-estimation of the true overall national costs in the Netherlands is not clear.Some insights may be gained by considering the contribution of the cost estimates from the single study conducted in the Netherlands to the overall national cost calculations . The stuOther sources of heterogeneity may have arisen from differences in study designs, ranging from retrospective analyses to a clinical trial setting Table . FurtherThe prevalence rate of ADHD in children and adolescents in the Netherlands is not known. Consequently, a prevalence rate from Germany was used as a proxy, which has face validity but the consequence of which is that the true prevalence rate of ADHD in the Netherlands may be under- or overestimated. Nevertheless, even if a prevalence rate of 2.1 % for diagnosed and treated Dutch ADHD patients was used , as was There are a number of other factors that suggest an underestimation of ADHD-related costs. For example, not all relevant cost categories were included, because of lack of data. There were no studies reporting costs to the justice system, substance abuse treatment, or traffic accidents. It is reasonable to assume that ADHD would impose costs in these areas , 48, 52.Furthermore, the present study included only costs related to ADHD in children and adolescents. When considering potential future income losses to children with ADHD as adults in the work force, the annual national costs of ADHD in children and adolescents increased to approximately €1.5 billion. Costs of ADHD directly attributable to adult patients, however, were not evaluated because there were no European-based studies on the topic. Nevertheless, it is known that ADHD persists into adulthood  and the There were also factors that may have contributed to an overestimation of the national cost estimates in the present analysis. Most studies that were used in the analysis reported cost estimates that were not adjusted for possible confounders. For example, it is well established that ADHD is commonly associated with comorbidities such as depression, anxiety, bipolar mood disorder, and conduct disorders , 53, 62.In summary, the findings in this study offer a broad estimation of the societal costs of ADHD. While acknowledging the limitation of the analysis, the societal economic impact of ADHD for the Netherlands remains large. In addition, as the impairments associated with the disorder are multi-faceted and occur in multiple settings, societal costs associated with ADHD also impact multiple public sectors in addition to healthcare, with the majority of the costs lying outside of the healthcare sector.Supplementary material 1 (DOCX 58 kb)Supplementary material 2 (DOCX 67 kb)Below is the link to the electronic supplementary material.


Adult attention deficit hyperactivity disorder (ADHD) increases the risk of several psychiatric disorders, like substance use disorders (SUDs).This study aimed to predict the tendency for drug use from child and adult ADHD symptoms in adults among male students from Tabriz University, Iran.For this purpose, 361 students were selected via a stratified random sampling from different faculties of Tabriz University. The students completed the Conners Adult ADHD Rating Scale self-report form and subscale (CAARS) questionnaire, Addiction Acknowledgment Scale (AAS) and MacAndrew Alcoholism Revised-Scale (MAC-R).To analyze the data Pearson correlation and multiple regressions (step by step) were used. Results indicated that there is a significant relationship between scores on the AAS and MAC-R via child and adult ADHD symptoms (P = 0.01). Moreover, we found that those with the highest addiction acknowledgment (13%) exhibited adult ADHD  and child ADHD. Alcohol potential (15%) was related to scores of child ADHD and impulsivity.According to this result behavioral disorders, especially ADHD, have an effect on the tendency to use drugs and therefore the primary treatment of behavioral disorders could prevent future drug abuse. Attention deficit hyperactivity disorder (ADHD) is a disorder that has become better recognized in adults during the past few years, with a reported prevalence of 1.0 – 2.5% in the Netherlands . These m1) Is there any relationship between adult ADHD  and child ADHD via addiction acknowledgment and alcohol potential?2) Which of the studied variables can better predict addiction acknowledgment and alcohol potential?The aim of the present study was to predict tendency to use drugs  by child and adult ADHD symptoms among adult students of Tabriz University.The method of this research is descriptive-correlational. Multivariate regression was used for the statistical analyses. The statistical population of this research was 5129 students in faculties of Tabriz University, the sample was selected from this population. The sample for the present study consisted of 361 male students from the Tabriz University who were selected by stratified random sampling.Four questionnaires were used in this study.1) Conners Adult ADHD Rating Scale self-report form and subscale (CAARS).To date, the Conners Adult ADHD Rating Scale (CAARS) is frequently used in the assessment of adult ADHD . The CAA2) Wender Utah Rating scale (WURS): The Wender-Utah Rating Scale (WURS) was developed to question childhood symptoms of ADHD retrospectively as an aid for the diagnosis of ADHD in adults . It is b3) Mac Andrew Alcoholism-Revised Scale: This measure is a 49-item scale developed with the original MMPI to distinguish alcoholic psychiatric patients from nonalcoholic psychiatric patients. A high MAC-R Scale score is associated with substance abuse potential and other addictive problems such as pathological gambling. At-score cut off of 60 on the MAC-R Scale is suggestive of high addiction potential. The scale seems to be effective with both men and women, as well as inpatients and outpatients . Khodaya4) Addiction Acknowledgment Scale (AAS): The development of the AAS began with a rational search through the MMPI-2 item pool for items with content indicating substance-abuse problems. Fourteen such items were found. Items not contributing to internal consistency were dropped and replaced by two items that improved scale internal consistency. The AAS is made up of 13 items. Research has shown that the AAS discriminates well between substance abuse samples and samples of either psychiatric patients or normal . In thisResults are presented according to the research questions posed above.1) Is there any relationship between adult ADHD and factors such as; inattention, hyperactivity, impulsivity, problems with self-concept, and child ADHD via addiction acknowledgment and alcohol potential? In order to answer this question, the Pearson correlation and analysis of regression methods were used. The results demonstrated that the correlation between addiction acknowledgment and alcohol potential via all the predictor’s variables is significant .2) Which of the studied variables can better predict addiction acknowledgment and alcohol potential? The second research question was examined by regression analysis, and the results are presented in To sum up the findings of the current study, addiction acknowledgment was positively predicted by adult ADHD  and child ADHD, and alcohol potential was positively predicted by child ADHD and impulsivity. These findings are supported by another study’s results which were obtained from different age groups -11. In e


Paralinguistic style, involving features of speech such as pitch and volume, is an important aspect of one’s communicative competence. However, little is known about the behavioral traits and cognitive skills that relate to these aspects of speech. This study examined the extent to which ADHD traits and executive functioning (EF) related to the paralinguistic styles of 8- to 12-year-old children and their mothers. Data was collected via parent report (ADHD traits), independent laboratory tasks of EF , and an interactive problem-solving task (completed by mothers and children jointly) which was coded for paralinguistic speech elements . Dyadic data analyses revealed that elevated ADHD traits in children were associated with a more exaggerated paralinguistic style  for both mothers and children. Mothers’ paralinguistic style was additionally predicted by an interaction of mothers’ and children’s ADHD traits, such that mothers with elevated ADHD traits showed exaggerated paralinguistic styles particularly when their children also had elevated ADHD traits. Highlighting a cognitive mechanism, children with weaker inhibitory control showed more exaggerated paralinguistic styles. The phrase, ‘Use your inside voice!’ is frequently uttered within homes, and highlights our expectations for individuals to communicate in a particular manner. An individual’s style of speaking includes several paralinguistic features . EF refers to higher order processes that aid in the monitoring and control of thoughts/actions and facilitate goal-directed behavior . Though pression  and traupression . HoweverThe role of EF for communication poses important implications for individuals who show weaknesses in EF, such as amongst those with diagnoses of Attention-Deficit/Hyperactivity Disorder ADHD; , as wellAttempting to fill gaps in the literature, this study focused specifically on examining the paralinguistic styles of mothers and children during an interactive task. We isolated paralinguistic qualities, including the features of volume mean ; volume variation ; pitch mean ; and pitch variation . We chose to assess these speech qualities during a mother–child interaction as previous work has highlighted the degree to which ADHD traits, in either a mother or a child, impact content of the interpersonal exchange. For example, mothers with increased ADHD symptoms demonstrate less corrective feedback to their children and use shorter, less complex, and less elaborate language with their children , while cThe second research aim was to determine whether, for children, EF accounted for a more exaggerated paralinguistic style. Accordingly, regression analyses were conducted to assess the degree to which children’s performance on EF tasks  related to a paralinguistic style that was more exaggerated . Note that while we were interested in assessing whether children’s EF skills may be responsible for the relation between ADHD, mediation analyses were not conducted due to the assumption of causality that is implicit within mediation analyses. That is, mediation analysis implies that the mediator is ‘caused’ by the predictor . Recent SD; one on the cognitive flexibility task and another on the child’s paralinguistic data). This resulted in a final sample of 57 dyads . Twenty-two of the remaining children had previous diagnoses, and 20 of these children were prescribed stimulant medication for ADHD traits (with 11 taking their medication on the day of testing1).Participants consisted of 68 pairs of community-recruited mothers and children (aged 8–12 years). Forty-three children were reported to be typically developing, while 25 were reported to have received a previous diagnosis of ADHD from a physician (2), pediatrician (9), or psychologist . As ADHD traits operate on a continuum and exist within non-clinical samples e.g., , childreThe present research was part of a larger study on children’s communicative behavior and consisted of one 90-min session for each dyad. This study was approved through the Office of Research Ethics at the University of Waterloo. Mothers completed questionnaires independently while children completed the EF tasks with a researcher in a separate room. All tasks were presented in a fixed order, a standard practice when assessing individual differences that ensures that individuals are exposed to identical stimulus contexts. Subsequently, the mothers and children participated in an interactive task together.Not At All to (3) Very Much. The SNAP-IV has acceptable internal consistency, item selection, and factor structure, all consistent with the constructs of ADHD put forth in the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition  Very Much/Very Frequently. The Conners scale demonstrates good internal consistency and predictive validity  and the CAARS-S . Given this, and consistent with current factor analytic studies supporting the use of a general factor of ADHD . Dyads were provided with a relatively open-ended collaborative problem-solving task based on a task used by youth groups , and whiTable  Cronbach’s alpha for the exaggerated paralinguistic composite was 0.69 for children and 0.60 for mothers.To obtain measures of paralinguistic styles for children and their mothers, each video was converted into an auditory file using the VLC media player . ResearcTable 1 provides the demographic characteristics of the sample. The ratings of mothers’ and children’s ADHD traits showed a wide range that was normally distributed and within acceptable limits for skew/kurtosis. Mean levels of ADHD were within the non-clinical range. There were no significant correlations between children’s age and ADHD traits (p = 0.83), but age was correlated with exaggerated paralinguistic style, r = -0.30, p = 0.03, and as such was controlled in further analyses. A t-test revealed no significant difference between male and female children on the exaggerated paralinguistic aggregate, p = 0.82, nor was gender significantly associated with any other key variables included in the study, ps > 0.09. As such, gender was not included in further analyses.r = 0.40, p = 0.003 , suggesting that a dyadic approach to the analyses is important given the influence that mother/child paralinguistic behaviors have on each other.The bivariate correlation between the mothers’ and children’s paralinguistic behavior was significant, Figure 1 as horizontal lines representing the standardized regression weights), and partner effects   , as wellp = 0.001. In addition, a significant partner effect emerged for mothers, such that increased ADHD traits in children were significantly associated with a more exaggerated paralinguistic style in mothers, β = 0.35, p = 0.012. Thus, increased child ADHD traits related to more exaggerated paralinguistic styles in both children and mothers.Addressing our first research question, the analyses revealed a significant actor effect for children, such that increased ADHD traits were significantly associated with a more exaggerated paralinguistic style, β = 0.45, p = 0.97), nor was the interaction term a significant predictor of children’s paralinguistic aggregates . However, a significant interaction effect emerged with respect to mother’s paralinguistic style, β = 0.53, p < 0.001 . Tests of the simple slopes suggested that when mothers’ ADHD traits were low, children’s ADHD traits did not influence mothers’ paralinguistic style . However, when mothers’ ADHD traits were high, having a child who demonstrated low levels of ADHD traits was associated with a more subdued paralinguistic style in mothers, while having children with higher levels of ADHD traits was associated with a more exaggerated paralinguistic style in mothers .The pattern for maternal ADHD traits showed a more complex pattern. That is, we did not find that the ADHD traits of mothers related to the paralinguistic style of their children , suggesting that mothers did not tend to report comparable levels of ADHD traits for themselves and their children. In addition, once controlling for ADHD traits, the correlation between mothers’ and children’s paralinguistic aggregates was not significant .The percentage of variance in the paralinguistic aggregate explained by ADHD traits  was 21% for children and 36% for mothers. In terms of other findings, we did not find a significant correlation between ADHD traits in mothers and children , but not working memory or cognitive flexibility (ps > 0.54).Correlations between children’s ADHD traits, EF, and the paralinguistic aggregate are shown in p = 0.001), as was age . The regression model with these two predictors accounted for a significant amount of variance in children’s paralinguistic style, R2 = 0.26. When inhibitory control was entered alongside age and ADHD traits in the second step, there was a significant increase in the variance explained by the model, where the change in R2 = 0.08 (together accounting for 34% of the variance). Both ADHD traits and inhibitory control were significant predictors of children’s paralinguistic style . Thus, children with elevated ADHD traits, as well as those with weaker inhibitory control, show a more exaggerated paralinguistic style, with both characteristics accounting for unique variance. . Volume variability was found to have a stronger relation with ADHD traits than all other paralinguistic features (ps < 0.02), which did not differ from each other (ps > 0.36). In addition, Fisher’s z-tests revealed no significant differences in the strength of the relations between inhibitory control and each paralinguistic feature, controlling for age (ps > 0.19)).Addressing the second research question, hierarchical regression analyses were conducted to examine the extent to which EF was related to paralinguistic style. At the first step of the regression, ADHD traits were a significant predictor of paralinguistic style .Given the relevance of paralinguistic style for both communicative development and impression formation, it is important to understand individual differences that may contribute to variability in speech styles. The present study provides insight into the degree to which maternal and child ADHD traits, and children’s EF skills, related to their paralinguistic style.content of children’s utterances . This was true even after controlling for mothers’ paralinguistic style . Thus, it seems as though mothers with elevated ADHD traits are more impacted by the behavioral styles of their children, which are manifest through their paralinguistic styles. These findings are interesting to consider in the context of past work examining the “similarity-fit hypothesis” which posits that parents and children may have better interactions when there is a similarity in ADHD symptomatology. Conflicting support for such hypotheses have been yielded, whereby some studies, supporting the similarity-fit predictions, have found that high maternal traits ameliorate the negative effects of child ADHD on parenting e.g., , 2008. IThird, we found that inhibitory control contributed to children’s manner of speaking. That is, children with weaker inhibitory control (but not working memory or cognitive flexibility) showed a more exaggerated paralinguistic style. Such a finding suggests that an individual’s paralinguistic style is something that is, at least in part, reliant on cognitive resources. Moreover, such a finding allows for speculation about the meaning of the exaggerated style – that is, that it may reflect a less controlled, more chaotic manner of speaker as opposed to a controlled, but more exuberant or excited style. However, as noted above, the impact for such a paralinguistic style for impression formation or interpersonal interactions cannot be determined from our data and will be an important avenue for future research. Regardless, findings add to a growing body of work highlighting the role of inhibitory control for other aspects of communication, such as suppressing one’s own perspective in order to take the perspective of a conversational partner , 2012. IThe present work advances the understanding of the role of ADHD traits and inhibitory control in communicative behavior. However, a number of limitations should be noted. First, the functional impact of an exaggerated paralinguistic style, and more specifically how it may impact one’s social functioning, cannot be ascertained from this study. That is, it would be of interest for future work to examine how others interpret an exaggerated paralinguistic style and whether such a style impacts the reaction of one’s communicative partner. Certainly, there is some emerging work suggesting that paralinguistic styles influence adults’ ratings of speakers’ socio-communicative competency . Moreovecontent of communication, this is the first to show their importance in predicting an individual’s manner of speech. Findings have implications for theoretical models of communication, which identify executive functions as an important factor in the development of children’s communicative skills, as well adding to the growing literature as to how ADHD traits relate to one’s own as well as others’ communicative behavior.In sum, the paralinguistic features of one’s speech represent an important aspect of one’s communicative approach. The present work highlights the role of ADHD traits and inhibitory control for a paralinguistic style that is more exaggerated and unrestrained. While previous studies have found that these individual factors relate to the EN participated in/supervised the design, data collection, analyses, and manuscript-writing; AR analyzed the data and contributed to the conceptual framework in writing the manuscript; NE designed the study, collected data, and contributed to the writing of the manuscript; SM collected data as part of her honors thesis and contributed to the writing of the manuscript.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


Low birth weight (LBW) remains the main cause of mortality and morbidity in infants, and a problem in the care of pregnant women world-wide particularly in developing countries. The purpose of this study was to describe the socio-demographic, nutritional, reproductive, medical and obstetrical risk factors for delivering a live LBW infant at Harare Maternity Hospital, Zimbabwe.A secondary data analysis from data obtained through a questionnaire and delivery records was conducted. Linear regression models with a complimentary log-log link function were used to estimate the relative risks for all LBW, term LBW and preterm LBW.The frequency of LBW was 16.7%. Lack of prenatal care , mother’s mid-arm circumference below 28.5 cm,  and rural residence  increased the risk of LBW. Eclampsia, anemia, and ante-partum hemorrhage, were associated with LBW , respectively. Malaria increased the risk of LBW . Prenatal care, infant sex, anemia, antepartum hemorrhage, premature rapture of membranes and preterm labor were associated with the three LBW categories. History of abortion or stillbirth, history of LBW, malaria, eclampsia, and placenta Previa, were associated with all LBW and preterm LBW, while pregnancy induced hypertension, and number of children alive were associated with all LBW and term LBW.LBW frequency remains high and is associated with nutritive, reproductive, medical and obstetrical factors. Preterm LBW and term LBW have similar and also different risk factors. Understanding the role of different risk factors in these different LBW categories is important if the goal is to reduce LBW frequency, and its complications, in Zimbabwe. Low birth weight (LBW) defined as a birth weighing 500 grams and above but below 2,500 grams irrespective of gestational age, continues to be a problem world-wide –4 and a LBW can be a consequence of preterm birth (PTD), which is birth before 37 completed weeks of pregnancy, or fetal growth restriction or intrauterine growth restriction (IUGR), which means that a baby doesn’t gain the appropriate weight before birth , 12, 15.LBW is a problem of maternity care in Zimbabwe, with prevalence ranging from 10.8% to 24.3% –12, 17. In this paper we report findings from a secondary analysis of data from a study which primarily assessed risk factors for preterm birth, conducted among women delivering at Harare Maternity Hospital between March and June 1999. While the data is from 1999, apart from the role of HIV/AIDS, prevalence of LBW remain the same at 11.0% , 17, 21,In this present day analysis, the main outcome of interest was LBW, which was later categorized into term LBW, and preterm LBW infants, based on information collected from the medical records. Women were identified as having delivered a singleton LBW live infant if the infant weighed 500 grams, but below 2,500 grams at birth, irrespective of gestational age. Women who delivered a”normal weight, term” infant were all women who delivered a live-born singleton baby weighing 2,500 grams and more at term (37 weeks of gestation and above). Term LBW infants were defined as term infants who weighed more than 500 grams, but below 2,500 grams. Preterm LBW infants were defined as preterm infants who weighed more than 500 grams, but below 2,500 grams.Based on original study , each daFor socio-demographic factors, age of mother was calculated as the number of years from her date of birth to her previous birthday. Information of marital status , education of mother and father , employment status of mother and father (yes/no), residence , if they had electricity (yes/no), had water supply (yes/no), and had a toilet (yes/no), were obtained by interview.For lifestyle factors, information on alcohol drinking , or drank home brew (mahewu), were obtained through the questionnaire. Mahewu is a local non-alcoholic nutritious beverage made from corn meal, rapoko or sorghum, soya beans and sugar . ChibukuFor anthropometric measurements, weight and height at first prenatal care visit of the mother were collected from medical records. Body mass index (BMI) was calculated as weight of mother at first contact, in kilograms divided by height in meters squared. Mid-arm circumference (MUAC) was obtained by measuring the length between shoulder and the elbow with arm bend, with circumference measured at the midpoint . MUAC waMothers were grouped into those who attended at least one visit of prenatal care during pregnancy or otherwise. Parity , prior history of abortion , stillbirth or LBW birth (yes/no) sex of the infant, and infant birth weight were abstracted from obstetrical records . InformaWhen one is carrying out research on humans in Zimbabwe, it is required to get approval from and register the project with the Medical Research Council of Zimbabwe, which in turn gets the Research Council of Zimbabwe’s approval. This process involves seeking permission from the Permanent Secretary of Health and from the departmental heads of any institutions defined in the proposal. The principal investigator was responsible for processing this approval. The University of Michigan Institutional Review Board permission was also obtained prior to this study. The medical record review did not use personal identities and we requested exempt status for that portion of the study. A consent form, translated into Shona, was signed by each individual study participant. The study therefore, was approved by the University of Michigan Institutional Review Board and the Medical Research Council of Zimbabwe and permissions were obtained from the Ministry of Health and Harare Central Hospital. This article is based on secondary analysis of these data, therefore exempt for IRB.Figshare in SPSS and SAS format; direct links:We have submitted the dataset to Feresu, Shinga (2015): LBW data. figshare.http://dx.doi.org/10.6084/m9.figshare.1348840http://figshare.com/articles/LBW_data/1348840 Retrieved 14:10, May 11, 2015 (GMT)Feresu, Shinga (2015): LBW SAS data. figshare.http://dx.doi.org/10.6084/m9.figshare.1348839 Retrieved 14:02, May 11, 2015 (GMT)http://figshare.com/articles/thirdphase_sas7bdat/1348839Since a complete population of live births over a 3-month period within the hospital was collected, we estimated the relative risks of LBW, and its sub-sets . In univariable analysis, crude relative risks, 95 percent confidence intervals and chi-square tests were calculated from cross-tabulations with each pair of the outcome variables  and each risk factor (determinants or exposures) to assess the association between each potential risk factor and either all LBW, term LBW, or preterm LBW using EPINFO version 7. We grouped risk factors into major subsets including, socio-demographic; anthropometric and nutritional factors; reproductive factors; medical and obstetrical complications; and infections, in our crude analysis.We then fitted generalized linear regression models with a complimentary log-log link function, because of the nature of our data, to estimate the adjusted relative risks of all LBW for these risk factors –29. We lAmong the 3,110 live births at Harare Maternity Hospital over the 3-month period 16.7% (n = 520) were LBW births, of which 60 (11.5%) were VLBW and 18 (3.5%) were ELBW. About 493 (15.9%) were preterm births, 199 (6.4%) were term LBW, 302 (9.7%) were preterm LBW, and only 191 (6.2%) were preterm without LBW.Age of mother ranged from 13 to 49 years (mean = 24.4 years). Very few mothers (7.3%) were above 34 years old, in The mean maternal weight (and standard deviation) was 64.7(±11.4) kilograms (range = 25–135 kilograms), BMI 26.0 (±4.6) (range = 11.4–36.8) and MUAC was 27.5(±3.2) cm (range = 17.5–43 cm). In crude analysis, women with BMI ≥ 25 were 91% less likely to have a LBW, and 55% less likely to deliver a term LBW infant compared with women with BMI 18.49 to less than 25, in During pregnancy, about 27.1% of the women drank alcohol, and most women (90.2%) reported drinking a local non-alcoholic nutritional beverage (mahewu). Alcohol drinking was associated with increased risk of LBW, and preterm LBW in the crude analysis, in About 87% of women received prenatal care, in The frequency of mothers diagnosed with malaria during pregnancy or urinary tract infection was less than 3%, in The frequency of mothers diagnosed with medical or obstetrical complications, except for pregnancy induced hypertension and PROM was low, in Hypertension had a 47% increase in the risk of all LBW infants only. On the other hand, pregnancy induced hypertension was associated with 31% increase in all LBW, and 53% increase in term LBW infants. Also, eclampsia was associated with 3.25-fold increase in all LBW, and 3.95-fold increase in preterm LBW. Ante-partum hemorrhage was associated with all the three forms of LBW, 3.42-fold, 2.78-fold and 5.38-fold increase, for all LBW, term LBW and preterm LBW, respectively. Placenta Previa was associated with 2.15 times increase in risk of all LBW, and 5.60 times increase risk of in preterm LBW. History of PROM was associated with a 2.43 times risk of all LBW, 1.77 times increased risk of term LBW and 3.96 times increased risk of preterm LBW. Also, history of PTL with a 5.39-fold increase in the risk of all LBW, 3.21-fold increase in the risk of term LBW and 12.79-fold increase in the risk of preterm LBW infants.This paper, using a secondary data analysis, with a full data complement for over a 3-month period, estimated and examined risk factors for all LBW, term LBW and preterm LBW, among mothers delivering live births at the largest referral center in Harare, Zimbabwe. Our results suggest that the frequency of LBW is high; that nutritional factors, prenatal care, history of abortion, previous LBW, stillbirth, obstetric complications including anemia, hypertension, pregnancy induced hypertension, eclampsia, ante-partum hemorrhage are important predictors of LBW in this population. Having PTL and PROM were associated with LBW. Infection with malaria during pregnancy was also associated with LBW.The prevalence of LBW among live-births at Harare Maternity Hospital over a three-month period of 167/1000 live births is comparable to the 168/1000 live births observed at the same hospital , 9–12. TThe LBW rate in a population is a good indicator of a public health problem that includes long-term maternal malnutrition, ill health and poor health care. On an individual basis, LBW is an important predictor of newborn health and survival. Limited data from Zimbabwe suggests that LBW is a common obstetrical problem , 9–14, aWe note that some conditions such as, prenatal care, infant sex, anemia, antepartum hemorrhage, PROM and history of preterm labor were associated with the three LBW categories; all LBW, term LBW and preterm LBW. Conditions like history of abortion or stillbirth, history of LBW, malaria during pregnancy, eclampsia, and placenta Previa, were associated with all LBW and preterm LBW. While, pregnancy induced hypertension, and number of children alive tend to be associated with all LBW and term LBW infants. Infections tend to be associated with preterm LBW. Chronic conditions tend to be associated with term LBW, while acute conditions tend to be associated with preterm LBW. Some risk factors or determinants are common for both term and preterm LBW. These observations may have to do with the differences in etiology for intrauterine growth restriction versus, preterm birth, although both area subset of LBW. We discuss this phenomenon, in our previous studies , 13, 24.Poor nutrition measured through BMI and MUAC was adversely associated with LBW, as in previous studies –31, confAs would be expected , 19, 37,Although Harare is an urban setting, malaria appears to remain an important determinant of LBW in this population as has been shown previously , and in In this study we described the risk factors for LBW, a contributor of infant mortality, for women delivering at HMH. However, some potential limitations in our study warrant consideration. Our study focused on live-births as WHO uses this rate , 3, 6, bOur small sample size did not allow us to further explore term, term LBW, and preterm LBW birth relationships with risk factors in adjusted analysis, nor could we analyze for very low and extremely birthweight infants. Albeit, we were also able to examine crude risks for term and preterm LBW infants, a distinction that would be important for maternity care in this population. Importantly, we have shown that traditionally established risk factors including nutrition, prenatal care, maternal risk factors, medical conditions, obstetric complications and malaria remain important risk factors for LBW in this urban Zimbabwean population.Our study is among few studies evaluating risk factors for LBW in Zimbabwe. We have demonstrated similar and different risk factors for subsets of LBW. This step is important for targeted interventions. Programs aimed at improving women’s health focused on improving nutritional status of women remain of critical importance for this population. Perhaps most importantly, adequate and focused screening and evaluation of the role of infections, such as malaria, syphilis, and HIV comorbidity, shown to be a risk factor for LBW in previous studies , 23, 50,