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Milltown cemetery in west Belfast, scene of an attack at an IRA funeral in March 1988. Photograph: Paul McErlane/The Guardian It is one of the most important sources of information about the Troubles in Northern Ireland, a historical memory bank of data, stories and images used by scholars around the world. The Conflict Archive on the Internet (Cain) […]Read More
The government Of Greek Colonels with King Constantin II (centre), 26 April 1967. Photograph: Keystone-France/Gamma-Keystone via Getty Images Athens, April 25 King Constantine and the military members of the Government are still negotiating the terms on which the King will declare his acceptance of the new regime. There seems little doubt that Constantine will eventually […]Read More
Nations around the world are cracking down on online terrorist content, introducing legislation that penalizes sites and ISPs if they fail to remove suspect content. But that fight could pose a real threat to sites like the Internet Archive, a nonprofit that saves old copies of webpages and other digital information. In a blog post yesterday, the […]Read More
Huw Turbervill's recent edition of The Googly compared Kusal Perera's match-winning 153 against South Africa at Durban to Brian Lara's own match winning 153 against Australia at Bridgetown. Peter Roebuck covered that famous game in the May 1999 issue of The Cricketer and reminds us why Lara's performance was "perhaps… the best of any sort." Brian Lara […]Read More
A still from the film version of Slaughterhouse-Five, 1972. Photograph: Ronald Grant Slaughterhouse-Five, by Kurt Vonnegut (Cape, 30s) A bullet makes a small to entry and a messy exit. Enormities in the mind do the same. "Everything is supposed to be very quiet after a massacre and it always is, except for the birds. And what do […]Read More
2 September 1984: Anthony Burgess on Sophia Loren at 50, with image by David Steen. Photograph: Sophia Evans/The Observer Breathless doesn't cover it. 'I have just spoken to the divine Sophia Loren on the telephone,' begins Anthony Burgess's hyperventilating tribute to the star of Two Women and El Cid on the occasion of her 50th birthday ('Sophia La Stupenda', 2 September […]Read More


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Banners Illustrations & Vectors
233,541 banners illustrations & vectors are available royalty-free.
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This 100+ year old Item is rated Very Fine / Fine+. Light aging throughout. No creases. No natural defects.No surface rub.No tears. Light moisture wrinkling. Please note that this item has retained its original vertical crease line, which should be visible in the digital image. Also, please note that this is a greyscale image, and any discoloration on the digital image is an anomaly which will not be present on the actual item.
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Reconsolidation theory posits that upon retrieval, consolidated memories are destabilized and need to be restabilized in order to persist. It has been suggested that experience with a competitive task immediately after memory retrieval may interrupt these restabilization processes leading to memory loss. Indeed, using a motor sequence learning paradigm, we have recently shown that, in humans, interference training immediately after active task-based retrieval of the consolidated motor sequence knowledge may negatively affect its performance levels. Assessing changes in tapping pattern before and after interference training, we also demonstrated that this performance deficit more likely indicates a genuine memory loss rather than an initial failure of memory retrieval. Here, applying a similar approach, we tested the necessity of the hypothetical retrieval-induced destabilization of motor memory to allow its impairment. The impact of memory retrieval on performance of a new motor sequence knowledge acquired during the interference training was also evaluated. Similar to the immediate post-retrieval interference, interference training alone without the preceding active task-based memory retrieval was also associated with impairment of the pre-established motor sequence memory. Performance levels of the sequence trained during the interference training, on the other hand, were impaired only if this training was given immediately after memory retrieval. Noteworthy, an 8-hour interval between memory retrieval and interference allowed to express intact performance levels for both sequences. The current results suggest that susceptibility of the consolidated motor memory to behavioral interference is independent of its active task-based retrieval. Differential effects of memory retrieval on performance levels of the new motor sequence encoded during the interference training further suggests that memory retrieval may influence the way new information is stored by facilitating its integration within the retrieved memory trace. Thus, impairment of the pre-established motor memory may reflect interference from a competing memory trace rather than involve interruption of reconsolidation.
Citation: Gabitov E, Boutin A, Pinsard B, Censor N, Fogel SM, Albouy G, et al. (2019) Susceptibility of consolidated procedural memory to interference is independent of its active task-based retrieval. PLoS ONE 14(1): e0210876. https://doi.org/10.1371/journal.pone.0210876
Editor: Dhakshin Ramanathan, University of California San Diego, UNITED STATES
Received: July 30, 2018; Accepted: January 3, 2019; Published: January 17, 2019
Copyright: © 2019 Gabitov et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Data Availability: All data files are available from the Open Science Framework database using the following link: https://osf.io/7pvx5/?view_only=870603efb0a242e797daa442d469d279.
Funding: This work was supported by funding from CIHR grant (MOP 97830) to J.D. E.G. was supported in part by the European Union Seventh Framework Programme (FP7/ 2007-2013) under grant agreement no. 604102 (Human Brain Project) to A.K. and by postdoctoral fellowship provided by FRSQ. N.C. was supported by the I-CORE program of the Planning and Budgeting Committee and The ISF (grant 51/11).
Competing interests: The authors have declared that no competing interests exist.
The traditional consolidation hypothesis posits that new memories are initially labile and susceptible to interference, but become stable in the long term through a protein-synthesis-dependent process known as "consolidation" [1–3]. In the late 1960s, this view, however, was challenged due to evidence that, in rats, electroconvulsive shock induced loss of previously consolidated memory, but only if animals were exposed to a "reminder cue" [4]. Over the last two decades, similar loss of consolidated memory has been repeatedly demonstrated using, initially, pharmacological and, lately, behavioral interference in close temporal proximity to memory retrieval [5–15], but see [16]. Thus upon retrieval, consolidated memories are reactivated and may return to a labile state becoming, once again, susceptible to interference. Crucially, interference procedures after memory retrieval have been shown to be effective only if they were administered within a limited time-window, that is when memories were still "active". These findings were interpreted as support to the reconsolidation hypothesis, which postulates that memory retrieval can lead to memory destabilization, thereby necessitating another consolidation-like period of protein-synthesis-dependent stabilization, called "reconsolidation" [17]. Extending the reconsolidation explanation to memory enhancement, it has been proposed that the post-retrieval restabilization time-window constitutes a unique opportunity for potential adaptive memory modification [18]. Importantly, the underlying mechanisms of memory strength modification implied by reconsolidation are separate from those of memory acquisition and consolidation [19,20].
The reconsolidation theory considers retrieval as a necessary condition for mechanistic instantiation of memory updating process, interruption of which may lead to memory loss [5,6,9,19]. However, some animal studies suggest otherwise, hence providing evidence for the loss of consolidated memory upon pharmacological inhibition of retrieval [21–24]. The primary aim of the present study was thus to test whether active task-based memory retrieval is necessary to induce impairment of consolidated memories by interference experience in humans. Since pharmacological interventions are problematic and are often associated with increased risk in human subjects, we used a competing task as a post-retrieval interference manipulation. This approach is often considered as a safe alternative to injections of protein synthesis inhibitors to study susceptibility of consolidated memories to interference in humans [9,10,14,15]. Similar to pharmacological protocols, susceptibility of consolidated memory to behavioral interference is usually tested using a 3-day study design. On the first experimental day, a new memory is encoded during experience with a particular stimulus or task. On the second experimental day, this memory is then retrieved (or not) and manipulated by providing an interference experience with a new, competing stimulus or task. Finally, on the last experimental day, the strength of the memory is tested.
Recently, using a computerized version of the sequential finger tapping task adapted from Karni et al. (1995, 1998), we tested time-dependent effects of post-retrieval behavioral interference on a consolidated motor skill, a form of procedural ("how to"), practice-dependent memory, in humans [25]. In that study, we optimized the parameters of a 3-day motor sequence learning paradigm [9,10,16] and showed that only immediate post-retrieval interference, but not after an 8-hour delay, resulted in performance deficit of a consolidated motor skill on the following day. During the experiment, participants practiced one sequence on Day 1 (T-Seq), briefly performed that sequence (memory retrieval) and then practiced another new sequence (i.e., interference training; Int-Seq) on Day 2 and, finally, took part in a test session of both sequences on Day 3. The interference training was given either immediately or 8 hours after memory retrieval (ReInt and Re8hInt group, respectively). The impaired performance of the initially trained sequence in the ReInt group was expressed as a loss of post-training delayed gains in performance, a behavioral manifestation of motor sequence memory consolidation [9,26–28]. These gains were preserved in the Re8hInt group, similar to a control group that on Day 2 underwent memory retrieval without subsequent interference training. In line with previous studies [10,29,30], the detrimental effects of immediate post-retrieval interference were transient and performance levels in the ReInt group rapidly recovered with continued practice, raising the possibility of an initial failure in memory retrieval rather than its genuine decay [31]. This issue was addressed by estimating experience-related changes in motor serial task representations that are presumably reflected in an actual tapping pattern of the sequence [32,33]. We showed that performance improvement during the final test on Day 3 in the ReInt group was paralleled by progressive formation of a new tapping pattern and, therefore, most likely indicated new learning. No evidence for recovery of previously formed tapping patterns was found. Thus, the explanation of rapid rescue of previously established motor sequence knowledge following initial failure in its retrieval was not supported.
Here, to examine the necessity of memory retrieval to induce deficit in the pre-established motor skill, we tested an additional group using similar approach as described above but without active task-based retrieval of the T-Seq before interference training (NoReInt group) (Fig 1). Statistical inferences were made by comparing this group with the ReInt group. The Re8hInt group was used as a control group. We allowed for the possibility that without any additional experience with the T-Seq on Day 2, participants may have initial difficulty in memory retrieval and may show impaired performance on the following day regardless of the effectiveness of interference training. Based on our previous results [25], we predicted that in that case, the tapping pattern of the T-Seq during the test on Day 3 would become progressively more similar to the tapping pattern formed by the end of the initial training, indicating successful memory retrieval with continued practice. However, impaired performance of the T-Seq on Day 3 followed by formation of a new tapping pattern would indicate that previously-formed representations of the T-Seq are not available/ not accessible and that a new memory trace need to be rooted.
(A) sequential finger tapping task. A sequence initially trained on the Day 1 (T-Seq, left panel) and a novel sequence used during the interference training on Day 2 (Int-Seq, right panel). The two sequences were matched for number of movements per digit and mirror-reversed in relation to each other (in terms of order). (B) Experimental groups. On Day 1 all groups underwent training on the T-Seq consisted of 14 performance blocks. On Day 2 the memory for the T-Seq was retrieved (or not) using one performance block and the interference training on the novel Int-Seq was conducted according to the experimental group (NoReInt, ReInt and Re8hInt). On Day 3 the performance levels for the T-Seq were tested in all groups using 7 performance blocks; the performance for the Int-Seq was subsequently tested as well. In all sessions performance blocks consisted of 60 key-presses, equivalent to 12 possible sequences, and were separated by 25-second periods of rest.
Whereas studies on reconsolidation highlighted that consolidated memories are destabilised upon their retrieval, other evidence suggest that an effective retrieval experience can influence the way new information is stored [1,34,35]. Therefore, we also tested the impact of memory retrieval on acquisition of a new motor sequence knowledge encoded during the interference training by analysing data of the Int-Seq.
Ethics statement
All participants gave their written informed consent to take part in the study, which was approved by the Research ethics board of the RNQ (Regroupement Neuroimagerie Québec). All procedures were in accordance with the approved guidelines and regulations. Subjects were compensated for their participation.
For the current report we extended our previous work [25] by including an additional group. The current report is based on the analyses of data from 50 healthy young right-handed [36] adults (mean age = 24.42, SD = 3.75, 28 females) including data from 35 participants (ReInt and Re8hInt group) recruited previously. Participation in the study required that subjects are able to perform and learn the motor task. All participants reported no prior history of neurological or psychiatric illness, no brain injury and no addiction to drugs, alcohol or cigarettes (i.e., subjects were non-smokers or occasional smokers). Exclusion criteria included the current or chronic use of medication, any known learning disabilities and an attention deficit disorder. Only individuals with less than 1 year of formal music training participated in the current study. Professional typists and experienced gamers were excluded as well. All participants had normal quality of sleep, as assessed by the Pittsburgh Sleep Quality Index questionnaire [37], and reported at least 6 hours of proper nocturnal sleep night before each experimental session. For follow-up, participants were asked to fill the Consensus Sleep Diary [38] (S1 Table). Throughout the experiment, participants were asked to refrain from drinking alcohol, not to take naps and to follow their normal sleep schedule. Between experimental sessions, they were instructed to continue with their regular routine.
Motor sequence learning task
The task protocol used in the current study has been described in detail elsewhere [25]. Briefly, the participants were required to perform a computerized version of the sequential finger tapping task adapted from Karni et al. (1995, 1998) implemented using the Psychophysics Toolbox extensions for Matlab (The Mathworks, Inc., Natick, MA). Lying supine, participants were instructed to tap "as fast and accurate as possible" a 5-element sequence of finger movements with their left (non-dominant) hand using a 4-key response pad (Fig 1A). During each session, periods of rest (25 s) and performance (i.e., performance blocks, 60 key-presses) were marked by visual stimuli (red and green fixation cross, respectively) presented in the middle of the screen. This protocol controlled for the number of movements executed per block to ensure that the same sensory-motor experience with the task was afforded across participants during a particular session. Throughout the experiment, no feedback was afforded.
Design and experimental procedure
The study consisted of three experimental phases, each taking place on three consecutive days: (1) initial training, (2) interference training with / without prior retrieval of the consolidated memory and (3) testing (Fig 1B). For each participant, each experimental phase started at approximately the same time of day to minimize putative impact of circadian and homeostatic factors on individual performance levels throughout the experiment [39]. During training, participants were instructed to perform a sequence, 1-4-2-3-1 (T-Seq) on Day 1 and 1-3-2-4-1 (Int-Seq) on Day 2, for 14 successive performance blocks. On Day 2, each participant was assigned to one of the following conditions: interference training without memory retrieval experience, memory retrieval juxtaposed to interference training and memory retrieval separated from interference training by 8-hour delay (NoReInt group, n = 15; ReInt group, n = 20; Re8hInt group, n = 15, respectively). In the ReInt and Re8hInt group, memory for the T-Seq was retrieved using a single performance block. Participants in the Re8hInt group left the laboratory after the retrieval experience. They were instructed to continue with their regular routine and were re-exposed to the experimental environment during the interference training 8 hours later. Thus, participants of each group took part in two equivalent training sessions practicing the T-Seq on Day 1 and the Int-Seq on Day 2. The only difference between the groups was the existence and timing of the short re-exposure to the T-Seq through its actual performance prior to the second interference training session. During the test on Day 3, all participants were instructed to perform the T-Seq, followed by the Int-Seq, tapping each sequence for 7 successive blocks. The decision to test the T-Seq first rather than using a counterbalanced design was made to exclude the possibility of proactive interference from additional experience with the Int-Seq and task-switching cost on the T-Seq performance during the test [40]. In this way, we could disentangle the impact of memory retrieval on the effectiveness of behavioral interference to induce deficit in a pre-established motor skill by comparing changes in performance over the post-training interval for the T-Seq in subjects with similar experience with the task. Moreover, the test of the Int-Seq on Day 3 allowed us to estimate how retrieval experience influences the way a new motor sequence knowledge is encoded and consolidated. Although we could not rule out the possibility of proactive interference caused by additional experience with the T-Seq prior to the test of the Int-Seq, given the same order in all groups we assumed that greater post-training gains for the Int-Seq will reliably reflect stronger memory.
Data analyses
Performance measures were calculated for each participant and, unless otherwise stated, the analyses were designed as mixed repeated measures Analysis of Variance (ANOVA) using individual values as a within-subjects factor and group as a between-subject factor. The results were corrected for non-sphericity violation using the Greenhouse-Geisser adjustment, when appropriate.
It has been consistently shown that experience and memory processes for explicitly known motor sequences are associated with substantial changes in performance rate while the number of errors is extremely low [27,28,41,42] (for accuracy rates observed in the current study, please, consult S1 File). Therefore, in the current study, the end-point measure for motor sequence task performance was a measure reflecting performance rate, i.e., the time (duration) per block spent at performing the motor sequence task [41,43]. To minimize the effects of additional practice during test sessions, skill levels were evaluated using data from a single block only. Furthermore, to account for warm-up effects and an underestimation of the actual level of skill acquired [44], performance measures were assessed using data from the final 30 key-presses (i.e., equivalent to 6 final sequences of the block; see also [45]). Post-training gains in performance rate were determined for each sequence using a percentage score based upon performance levels achieved during the last block of training so that positive values correspond to faster performance by Day 3 than by the end of training.
Changes in motor sequence representations were assessed by testing for experience-driven changes in a tapping pattern of a sequence. To this end, inter-key press intervals (IPIs), i.e., durations between successive key presses, of all correctly completed sequences were extracted for each performance block of interest, being classified according to one of 4 possible transitions between successive elements within a sequence plus an additional transition between the sequences. Average IPIs were then calculated separately for each of the five possible transitions excluding any value that was above or beyond two standard deviations from the mean. This procedure resulted in 5-element vectors of IPIs that represent individual tapping patterns of a sequence implemented during performance at different time-points of interest. Experience-driven changes in tapping patterns were assessed using normalized Pearson correlation coefficients calculated between two tapping patterns at different time-points of interest. The normalization was performed using Fisher z-transformation. Note that the correlation coefficients indicate the degree of similarity between tapping patterns (i.e., higher values corresponding to greater pattern similarity, and vice versa), but do not reflect changes in overall performance rate. Moreover, this approach takes into account the inter-subject differences in the way the tapping pattern is formed and modified by previous experience with the task [32,46,47], and allows to perform statistical inferences without making any assumption about the shape and experience-driven changes of the tapping pattern at the group level [25].
Encoding of a new motor sequence knowledge
The susceptibility of the pre-established memory to interference may depend on the efficiency of the initial training and memory trace dominance [48]. Therefore, through analysis of the data acquired during training sessions, we first validated that motor skill levels during memory encoding were comparable across groups. The equivalent experience afforded during the training of each sequence also allowed us to test for the impact of previous experience with the task (T-Seq) on acquisition of a new motor sequence knowledge (Int-Seq).
Performance rate.
Throughout both training sessions, time on task for a single block averaged across groups shortened from 12.50 ± .50 sec during the first block to 8.92 ± .35 sec during the last block for the T-Seq, and from 12.08 ± .59 sec to 9.02 ± .35 sec for the Int-Seq (mean ± s.e.m.) (Fig 2, Day 1 and Day 2 respectively). These robust within-session improvements in performance rate were significant across sequences and groups, as indicated by a significant effect of block (F(5.09, 239.41) = 40.01, p < .001) but no significant effect of sequence nor group (F(1, 47) = .02, p = .89; F(2, 47) = .11, p < .90 respectively). Although there was a trend towards a significant sequence by group interaction (F(2, 27) = 3.02, p = .06), post hoc analyses performed separately for each sequence showed no significant effect of group (F(2, 27) = .54, p = .59; F(2, 47) = .05, p = .96, T-Seq and Int-Seq respectively). Comparison between the sequences within each group also failed to show significant difference (F(1, 19) = 2.42, p = .13; F(1, 19) = 2.45, p = .14 and F(1, 19) = .72, p = .41, NoReInt, ReInt and Re8hInt group, respectively).
Time (i.e., duration) to complete the last 30 key-presses for each performance block during the training (Day 1), retrieval (Day 2) and test (Day 3) of the trained sequence (T-Seq, filled markers) as well as during the training (Day 2) and test (Day 3) of the interference sequence (Int-Seq, empty markers) is plotted for the NoReInt, ReInt and Re8hInt group (blue, magenta and yellow markers, respectively). Last training blocks, the retrieval block and first test blocks are time-points of interest (End-T, Retrieval and Test respectively). Bars–standard error of the mean (s.e.m.).
Tapping pattern of a sequence.
During training, the initial tapping pattern of a sequence (Fig 3A) changed so that the degree of similarity to the tapping pattern formed by the end of training progressively increased from .94 ± .15 to 1.77 ± .11 for the T-Seq, and from 1.15 ± .08 to 1.80 ± .09 for the Int-Seq (mean ± s.e.m., correlation coefficients for the first and the penultimate training blocks, respectively) (Fig 3B, Training). These changes were highly significant and comparable across sequences and groups, as indicated by a significant effect of block (F(6.94, 326.03) = 20.91, p < .001) with no significant effect of sequence, group nor any interaction (F < 1.24, p > .25). Thus, fast and robust gains in performance rate during the training were also associated with formation of a new, presumably more efficient kinematic pattern to generate each sequence. Our results indicate that motor skill levels achieved by the end of the initial training on Day 1 were comparable across groups. Moreover, memory encoding of a novel motor sequence knowledge on Day 2 was not affected by experience with the T-Seq on the previous day, nor by its retrieval.
(A) Changes in tapping pattern, i.e., pattern of inter-key press intervals, from the first to the last block during the initial training on Day 1 and interference training on Day 2 (upper and lower plot respectively) are shown for one representative subject. Each point represents mean duration for each of 4 possible transitions between successive elements within a sequence (from 1st to 4th) plus an additional transition between the sequences (between) for each block. Thus, shape of each line depicts a tapping pattern for a single block. With practice, tapping pattern progressively became more similar to the tapping pattern generated during the last training block (red line). Note that changes in tapping pattern (i.e., line shape) do not directly reflect changes in performance rate. (B) Degree of similarity between tapping patterns was assessed based on normalized Pearson correlation coefficients using the Fisher's z-transformation. Group average of individual normalized Pearson correlation coefficients between tapping patterns formed by the end of training (i.e., during the last training block) and each block during the training (training blocks 1–13) and test (test blocks 1–7) are shown for each sequence (T-Seq, upper plots; Int-Seq, lower plots). Bars–standard error of the mean (s.e.m.). *–significant results at .05 level, #–significant results at .01 level, n.s.–no significant differences.
The effect of memory retrieval on the strength of the practiced motor skill
Next, we addressed our main research question by comparing performance levels expressed on Day 3 to those achieved by the end of training. This comparison allowed us to test the effect of memory retrieval on post-training gains in performance for each sequence.
Performance rate.
Analysis of performance duration resulted in significant effect of time-point (F(1, 47) = 11.46, p = .001) with no significant effect of sequence, nor of group (F(1, 47) = 1.00, p = .32; F(2, 47) = .40, p = .67). There were, however, significant time-point by group and time-point by sequence by group interactions (F(2, 47) = 3.58, p < .05; F(2, 47) = 3.59, p < .05), suggesting substantial impact of retrieval processes on these post-training performance gains. To gain insight into differential effects of retrieval on off-line processes of each sequence, follow-up analyses were conducted separately for each sequence and each group (Fig 4A).
(A) Time to complete the last 30 key-presses during the last training block, the retrieval block and the first test block (End-T, Retrieval and Test respectively) is plotted for each group (NoReInt, ReInt and Re8hInt with blue, magenta and yellow markers respectively) and each sequence (T-Seq, filled markers upper plot; Int-Seq, empty markers lower plot). (B) Gains in performance, normalized to the last training block, that developed during the post-training interval for each sequence (i.e., between the end of training on Day 1 (T-Seq) or on Day 2 (Int-Seq) and the corresponding test session on Day 3; Post-T Gains) averaged across participants of each group (upper plot). Positive values correspond to faster performance by Day 3 than by the end of training. Individual Post-T Gains for the T-Seq (x axis) plotted against Post-T Gains for the Int-Seq (y axis) (lower plots). Bars–standard error of the mean (s.e.m.). *–significant results at .05 level, #–significant results at .01 level, n.s.–no significant differences. Note that in the ReInt group, regression analysis did not result in significant correlation even after excluding two participants with extremely negative values.
In the context of our main research question, remarkable results were observed in the NoReInt group that, similar to the ReInt group, failed to express additional post-training gains in performance rate for the T-Seq during the first test block on Day 3 (p = .67 and p = .75, NoReInt and ReInt group respectively) (Fig 4A, upper panel). Thus, by Day 3, the deficit in post-training gains for the T-Seq was observed regardless of whether or not memory for this sequence was retrieved immediately before the interference training. Note that significant post-training gains in performance rate for the T-Seq observed in the Re8hInt group (p < .01) suggest that short experience with the T-Seq during the retrieval block 8 hours prior to the interference training protected the retrieved memory from interference [25].
Comparing between performance levels achieved by the end of the interference training on Day 2 and during the corresponding test on Day 3, a deficit in post-training gains for the Int-Seq was observed only in the ReInt group (Fig 4A, lower panel). Without memory retrieval, however, participants in the NoReInt group developed robust gains during the post-training interval and performed the Int-Seq significantly faster on Day 3 than by the end of training on Day 2 (p < .01). The 8-hour interval between memory retrieval and interference training (Re8hInt group) also allowed for faster performance of the Int-Seq overnight (p < .05). Thus, memory retrieval juxtaposed to interference training prevented expression of post-training gains in performance not only for the T-Seq, but also for the Int-Seq. Note that given that the test for the Int-Seq was preceded by the test of the T-Seq, the possibility of proactive interference on the Int-Seq caused by additional experience with the T-Seq cannot be ruled out.
To test for potential effect of memory retrieval on the relationship between post-training gains expressed for each sequence on Day 3, regression analyses was conducted. To minimize the impact of individual differences in performance rate, post-training gains for each sequence were calculated in percentages relative to performance duration during the last training block so that positive values indicate additional improvement in performance, and negative values indicate performance deterioration (Fig 4B). To assess a moderation effect of memory retrieval, these values were mean-centered and entered into a hierarchical multiple regression analyses. In the first model, post-training gains for the T-Seq together with group factor (transformed to dichotomous variables) accounted for 28.5% of variance in consolidation gains of the Int-Seq (r2 = .285, F(3, 46) = 6.10, p = .001). In the second model, the interaction term between post-training gains for the T-Seq and group significantly increased the explained variance by 10.6% (r2 change = .106, F(2, 44) = 3.84, p < .05). The interaction between post-training gains for the T-Seq and group was also significant (F(5, 44) = 5.65, p < .001), suggesting that the relationship between post-training gains for each sequence depended on memory retrieval. A significant correlation between the post-training gains for the T-Seq and the post-training gains for the Int-Seq was observed only for the Re8hInt group (r = .22, p = .35; r = .38, p = .16; r = .81, p < .001, ReInt, NoReInt and Re8hInt group respectively). Note that the results in the ReInt group failed to be significant even after excluding two participants with extremely negative values (r = .41, p = .09). Thus, only participants with an 8-hour delay between memory retrieval and interference training were able to express consolidation gains for the Int-Seq proportional to the total post-training gains for the T-Seq. This result suggests that active task-based memory retrieval followed by a "protective" 8-hour interval not only contributes to the strength of the retrieved motor memory but is also proportionally beneficial for consolidation of a new motor sequence knowledge. Upon other interference conditions, however, the lack of significant correlation between post-training gains of the two sequences rules out the possibility of direct trade-off between the impairment of the pre-established motor memory and consolidation of subsequently acquired new motor knowledge.
Tapping pattern of a sequence.
By Day 3, the tapping pattern observed during the last training block underwent additional modification (Fig 3B). Analyses of the correlation coefficients of tapping pattern formed by the end of training (i.e., the last training block) with tapping pattern observed during each time-point of interest (the penultimate training block, the first test block) for each sequence (T-Seq, Int-Seq) resulted in a significant effect of time-point and sequence (F(1, 47) = 61.35, p < .001; F(1, 47) = 5.04, p < .05, respectively), as well as a significant time-point by sequence and a time-point by sequence by group interaction (F(1, 47) = 5.49, p < .05; F(2, 47) = 3.33, p < .05, respectively). These results suggest that during the post-training interval, tapping pattern formed by the end of training underwent significant changes that differed between sequences and groups. Post hoc comparisons performed separately for each time-point revealed that by the end of training all groups showed comparable degree of similarity between tapping patterns for both sequences (F(1, 47) = .06, p = .81; F(2, 47) = .96, p = .39; F(2, 47) = 2.14, p = .13, effect of sequence, group and sequence by group interaction respectively). By Day 3, however, the degree of similarity of tapping pattern to the one formed by the end of training for the T-Seq was significantly lower than for the Int-Seq (F(1, 47) = 10.14, p < .01) with no significant effect of group neither sequence by group interaction (F(2, 47) = .31, p = .73; F(2, 47) = 2.15, p = .13, respectively). Thus, during the post-training interval, tapping pattern for the T-Seq underwent greater modification compared to changes observed in the tapping pattern for the Int-Seq. These differences between the sequences did not depend on memory retrieval and may indicate that any experience with the task modifies its representation.
Genuine memory impairment rather than retrieval deficit
Does the deficit in post-training performance gains reflect a genuine memory impairment as opposed to the initial difficulty in memory retrieval? We addressed this question in our last analyses by assessing changes in performance rate and dynamics in the tapping pattern of the sequence during the test session on Day 3.
Performance rate.
Analyses of performance duration during the test of the T-Seq showed significant main effect of block across all groups (F(4.36, 205.06) = 3.95, p < .01) (Fig 2, Day 3). The post-hoc analyses performed separately for each group, confirmed that the main effect of block was significant in the NoReInt and ReInt group (F(6, 84) = 2.34, p < .05 and F(3.52, 66.79) = 3.33, p < .05, respectively). These results indicate that the deficit in post-training performance gains for the T-Seq in these groups was associated with fast within-test improvement in performance rate. This improvement raises the possibility of a transient failure in motor memory retrieval rather than its genuine impairment [31]. Analyses of performance duration during the test of the Int-Seq showed similar results (main effect of block: F(6, 84) = 2.24, p < .05 and F(4.15, 78.83) = 4.28, p < .01, NoReInt and ReInt group respectively).
Tapping pattern of a sequence.
Based on our previous results [25], we assumed that if within-test improvement in performance rate reflects an initial failure in memory retrieval and its rapid recovery with continued practice, then we should also find evidence for recovery of the previously formed tapping pattern. However, the analyses of the T-Seq tapping pattern dynamics during the test blocks, versus the last training block on Day 1, showed no significant effect of block (F(6, 84) = .52, p = .79; F(2.64, 50,14) = .59, p = .61 and F(3.60, 50,40) = 2.30, p = .08, NoReInt, ReInt and Re8hInt group respectively) (Fig 3B, upper plots), providing no evidence for recovery of the previously formed tapping pattern. Therefore, retrieval failure as a possible explanation for performance deficit for the T-Seq on Day 3 observed in the NoReInt group, similar to the ReInt group, is not supported. Yet, in both these groups, fast within-test improvement in performance rate of the T-Seq was paralleled by significant within-test changes in its tapping pattern. These changes were evident while assessing the degree of tapping patterns' similarity between the first and the remaining (i.e., 6 out of the 7) test blocks (main effect of block: F(3.88, 182.26) = 6.31, p > .001; block by group interaction: F(7.76, 182.26) = 2.02, p > .05; post-hoc analyses showed main effect of block for the NoReInt and ReInt group: F(5, 70) = 3.92, p > .01 and F(5, 95) = 8.37, p < 0.001, respectively) (Fig 5, upper plots). Thus, the rapid within-test improvement in performance rate of the T-Seq observed in the NoReInt group, similar to the ReInt group, did not result from a simple performance acceleration or delayed memory retrieval, but rather required or occurred due to a generation of a new, presumably more efficient, tapping pattern. In the Re8hInt group, on the other hand, no significant within-test changes in the tapping pattern of the T-Seq were observed, indicating reliable and stable task representations.
Degree of similarity between tapping patterns, i.e., patterns of inter-key press intervals, was assessed based on normalized Pearson correlation coefficients calculated for each individual using the Fisher's z-transformation. Mean normalized Pearson correlation coefficients between tapping patterns for the first test block and during the subsequent repeated practice (i.e., test blocks 2–7) for each group and each sequence (T-Seq, upper plots; Int-Seq, lower plots). Bars–standard error of the mean (s.e.m.). #–significant results at .01 level.
Assessing tapping pattern dynamics during the test session of the Int-Seq, noticeable results were observed only in the Re8hInt group. Across test blocks, the degree of tapping pattern similarity to the one formed by the end of interference training increased (F(3.12, 43.69) = 3.11, p > .05) (Fig 3B, lower right plot). This recovery of previously formed tapping pattern for the Int-Seq in the Re8hInt group was also associated with a trend towards decreased tapping pattern similarity to the one observed during the initial test block (F(5, 70) = 2.25, p = .06) (Fig 5, lower right plot).
The main goal of our study was to examine the necessity of memory retrieval to induce a deficit in a pre-established procedural ("how to") motor memory in humans [17]. To this end, we used a 3-day motor sequence learning paradigm which consisted of an initial training on Day 1, an interference training on Day 2, preceded or not by the actual task-based retrieval of the initially trained sequence, and a final test session on Day 3. Our results suggest that susceptibility of consolidated motor memory to behavioral interference is independent of its active task-based retrieval. Since active task-based retrieval is the most adequate mechanism to reactivate memories [49], the impairment of the pre-established motor skill in the absence of its retrieval challenges the reconsolidation view that considers memory reactivation as a necessary condition for susceptibility of consolidated memory to changes [5,6,9,19].
Yet, one may argue that upon exposure to the same context where the initial training was given, the memory trace for the trained sequence in the NoReInt group could have been spontaneously reactivated and temporarily destabilized even without actual / physical memory expression [21–24]. Indeed, human studies suggest that declarative and fear memories can also undergo reconsolidation-like processes following the presentation of the learned cue only [11,15,50]. If the re-exposure to the experimental environment may lead to spontaneous motor memory trace reactivation, then participants in the Re8hInt group should have also shown impairment of the pre-established motor skill. Participants in this group left the laboratory after the retrieval experience. They were instructed to continue with their regular routine and were re-exposed to the experimental environment during the interference training 8 hours later. However, on Day 3 the post-training gains in the Re8hInt group were comparable to the post-training gains expressed by participants that on Day 2 underwent memory retrieval without subsequent interference training (i.e., ReactNoInt group in our previous report [25]). Consequently, the hypothetical possibility for spontaneous memory reactivation by experimental context and its subsequent destabilization contradicts the absence of interference effects in the Re8hInt group and, therefore, is unlikely.
We suggest that the current pattern of results supports a memory integration model [1,35]. This model refers to the idea that memories for related experiences are stored as overlapping representations in the brain. Previous experience with the task and memory trace dominance may dictate the degree of such overlap influencing the way new information is stored. Accordingly, rather than memory destabilization and recapitulation of initial consolidation processes, memory reactivation immediately before interference training may have facilitated integration of new knowledge into previously established memory trace through its consolidation. The high overlap between neuronal ensembles representing memories for two different sequences could lead to mutual interference between these sequences [30,51,52]. Indeed, in the ReInt group, memory retrieval juxtaposed to interference training prevented expression of post-training performance gains not only for the T-Seq, but also for the Int-Seq. The integration model can also explain the time-dependent effect of retrieval experience on these gains in the ReInt and Re8hInt group.
The detrimental effect of interference training on the pre-established motor memory in the NoReInt group, similar to the ReInt group, was expressed as a lack of additional post-training gains, so that the performance rate for the T-Seq on Day 3 did not significantly differ from its performance rate achieved by the end of the initial training on Day 1 (Fig 4A, upper panel). Post-training delayed gains in motor skill levels are considered to be a behavioral signature for successful motor sequence memory consolidation [9,26–28,53,54]. Consolidation processes require time and, following practice on an explicitly introduced motor sequence, time-in-sleep to become effective [27,42,55–57]. Indeed, when participants performed the T-Seq as a retrieval procedure on Day 2, their performance was significantly faster than by the end of the initial training on Day 1 [25]. Given the very same training experience on Day 1, one would have expected similar consolidation gains in the NoReInt group on Day 2. Therefore, we assume that the lack of additional post-training gains on Day 3 in the NoReInt group, similar to the ReInt group, indicates that the detrimental effect of interference training on the pre-established motor memory was expressed as a loss of consolidation gains.
If the loss of consolidation gains for the T-Seq is the consequence of a failure in restabilization of the pre-established motor sequence knowledge [10], one would also have expected a greater reliance on task representation formed by the end of the initial training, i.e., before the newly encoded memory was stabilized through consolidation. However, during the test session on Day 3, performance of the T-Seq was characterised by decreased reliance on tapping pattern formed by the end of the initial training on Day 1 in all groups (Fig 3B, upper plots). This pattern of result did not change even after additional experience with the T-Seq on Day 3, as indicated by analyses of tapping pattern dynamics across test blocks, providing no evidence for rescue of previously established tapping pattern with continuous practice. Thus, intact and impaired performance levels for the T-Seq, as indicated by expression of consolidation gains in the Re8hInt group and their abolition in the ReInt and NoReInt group, respectively, were associated with decreased reliance on initially established task representation. Therefore, restabilization failure as a possible explanation for the loss of consolidation gains following behavioral interference is not supported.
On Day 3, the loss of consolidation gains for the T-Seq was also associated with fast within-test improvement in performance rate. Did this improvement reflect an initial failure in memory retrieval and its rapid recovery with continuous practice? If so, the within-test improvement in performance rate should have been paralleled by greater reliance on the previously established tapping pattern. However, the decreased similarity between the tapping pattern of the T-Seq on Day 3 and the tapping pattern formed by the end of the initial training did not significantly changed throughout the test blocks (Fig 3B, upper plots), providing no evidence for memory recovery. Yet, the tapping pattern of the T-Seq in the NoReInt group, similar to the ReInt group, underwent significant changes so that the degree of similarity to the tapping pattern generated by each participant during the first test block progressively decreased with practice (Fig 5, upper plots). These characteristic changes in the tapping pattern observed during the test were analogous to those observed during the initial training [25]. We propose that the loss of consolidation gains for the T-Seq in the NoReInt group, similar to the ReInt group, implies a genuine impairment of the motor skill memory. The explanation of a transient deficit in memory retrieval is not supported.
Significant post-training gains for the T-Seq in the Re8hInt group, but not upon other interference conditions, suggest that short retrieval experience followed by the "protective" 8-hour interval was sufficient to prevent unfavorable effects of the interference training even upon a hypothetical possibility for spontaneous memory reactivation by experimental context per se. It has been recently shown that a brief memory retrieval can result in significant learning and improve visual perception [58]. Moreover, repetitive task-based retrieval of the pre-established motor memory interleaved with new learning can also enable prevention of interference for the long term [59]. In line with these findings, our results suggest that active task-based memory retrieval can significantly contribute to the memory strength [58] and protect it from future interference in a time-dependent manner.
Despite similar impairment in performance observed for the T-Seq in the NoReInt and ReInt group by Day 3, two ways of conjectural memory reactivation, with or without its actual retrieval, resulted in differential competition between overlapping memories, as indicated by consolidation gains for the Int-Seq in the NoReInt group, but not in the ReInt group (Fig 4). These results are in line with the idea that trace dominance, determined by the intensity of previous experience in general and memory reactivation in particular, plays a crucial role in synergistic and competitive interactions between memories [48,60–62]. Here, similar performance levels and comparable improvements paralleled by changes in a tapping pattern were observed during both initial and interference training sessions in all groups. Therefore, the differential expression of post-training consolidation gains for the Int-Seq cannot be explained by differences in initial memory encoding and is more likely related to conjectural reactivation of overlapping, but distinct neural populations elicited with and without actual retrieval experience (ReInt and NoReInt group, respectively). It is not clear, however, whether the lack of spontaneous consolidation gains for the Int-Seq in the ReInt group resulted from competition between overlapping engrams during consolidation phase or during the recall. The possibility of proactive interference caused by additional experience with the T-Seq prior to the test of the Int-Seq cannot be ruled out [40]. In any case, the 8-hour interval between memory retrieval and re-exposure to experimental context during interference training allowed participants of the Re8hInt group to express significant post-training gains for both sequences. The observation that only in the Re8hInt group individual consolidation gains for the Int-Seq were proportional to the total post-training gains for the T-Seq supports the idea of time-dependent overlap and separation between retrieved and new memories.
The engagement of overlapping neuronal populations to represent consolidated and new memories may be governed by similar transient competitive processes that link distinct new memories encoded close in time [63–65]. It has been shown that learning triggers a temporary increase in intrinsic excitability of encoding neurons [66]. This increase contributes to a stronger stimulation of a particular synaptic pathway that leads to two dissociable events: local tag setting and the synthesis of diffusible plasticity related proteins (PRPs) [65] increasing the probability of the tagged synapses to be involved in encoding of another task learned shortly after [64]. The persistence of encoded memory traces depends upon consolidation processes through synaptic capture of PRPs [63,65]. Since the availability of PRPs generated in the cell bodies is limited, during consolidation of two memories encoded close in time, a "winner-take-all" scenario appears to prevail whereby some encoded traces persist in a stable manner whereas others do not [60]. Thus, transient increases in intrinsic neuronal excitability and competitive synaptic tagging and capture mechanism determine the distribution of synapses that are strengthened or weakened during learning [62]. Recently, studies on animal models provided convincing support for the transient and competitive nature of these processes demonstrating greater overlap between memories encoded close in time and greater separation between memories encoded farther apart in time [67,68]. This time-dependent co-allocation of memory traces may not be limited to linking new memories and may also occur following memory reactivation experience given immediately before new learning, as in the ReInt group, but not with 8-hour delay. Activation of overlapping networks during memory retrieval may create an interference problem at a behavioral level [52]. Thus, engagement of overlapping populations of neurons during encoding and "winner-take-all" competition for resources during memory consolidation provide a plausible framework for interpreting impaired performance associated with both, consolidation failure induced by new learning shortly after initial training [55,56,69,70] and the so-called "restabilization" failure allowed through memory reactivation [9,10,14,15,71,72].
It is noteworthy that during the post-training interval, greater changes in tapping pattern for the T-Seq, versus the Int-Seq, were observed in all groups irrespective of the retrieval-interference procedure (Fig 3B). These differences could be explained by unequal time interval after the end of each training session. However, this explanation is not supported by our previous observations [25]. By Day 3, the group that had no experience with the task during the post-training interval showed greater reliance on tapping pattern formed by the end of the initial training on Day 1 compared to all other groups. Thus, rather than a simple passage of time, our results suggest that any experience with the task modifies its representation. These changes can either strengthen or weaken previously established memories resulting in impaired or improved performance.
In conclusion, here we showed that, in humans, active task-based memory retrieval of the pre-established motor skill is not necessary to induce its impairment through behavioral interference. However, even upon the hypothetical possibility for spontaneous memory reactivation by experimental context without its actual task-based retrieval, the post-reactivation failure of memory restabilization proposed by the reconsolidation theory is not supported. Instead, the current pattern of results supports a memory integration model according to which reactivation-induced brain plasticity influences the way new information is stored and may facilitate its integration into previously established memory trace through its consolidation.
Supporting information
S1 Table. Demographic information and sleep duration.
S1 File. Supplementary results.
The authors would like to acknowledge the technical support of Arnaud Bore, Andre Cyr and Carollyn Hurst.
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Now next, you'll want to pick a WordPress theme from somewhere like ThemeForest, Elegant Themes or OptimizePress. This is the barebones design of your site, which you can then customize with your own branding, copy, and images. That being said, you don't want to cheap out. It costs less than $100 to buy a theme that will make your website look professional (and you can upgrade to a completely custom design once you get the business going).
Clickbank University is a course that Clickbank have developed in conjunction with some of its most successful affiliates - including the first affiliate to make $1million in one day... What is excellent about this course is that it covers everything you need to do in order to succeed as a Clickbank affiliate - and there's a great deal more to achieving success than just picking a product, sticking a link on your website and hoping...
It's simple to sign up as an affiliate of Clickbank - all you have to do is create an account, add in your preferred payment method (so that you can be paid any due commissions) - and you're good to go. That's the easy bit. You then go to the marketplace to find a product that you'd like to promote. Here's a good article by Clickbank on the basics of using the marketplace.
21. Facebook – Facebook swap shops are great for selling things locally. It's like CraigsList, but a little easier. You simply search for swap shops in your area and ask to join the group. Once you're in, take a picture of the item, write a quick description with the price and post it. It doesn't get much easier than that. You can generally expect to get about what you would get at a yard sale, maybe a little more.
Aweber offers a $1 trial account for all new customers. The account is just like a normal Aweber account and includes unlimited email campaigns, newsletter, broadcasts and follow ups. It's a great way to test drive Aweber to see what it can do for you. Your satisfaction is guaranteed. If you find that email marketing is not for you, contact Aweber within 30 days and they'll give you the $1 back.
If you are averse to the idea of working under somebody and would much rather prefer to be your own boss then this course is worth a look. Begin by understanding the basics and fundamentals of marketing before choosing a profitable affiliate niche, set up your website and promote affiliate products. Navigate through websites such as ClickBank, and Amazon among others, get high volume traffic that turns into sales. With lots of bonus content and constant support from the teacher, you will be able to reach your full potential.
Epic post! I've been hunting around various sites like Pat Flynn's and others, but they never put everything together as you have. Now it starting to make sense for once. So, I'm a newbie and don't even know the different between internet marketer and digital marketer or what this type of business is even called. I just want to learn this business and create a small passive income online in any niche. Because I know very little, I was actually planning to use this very same Sales Funnel in your diagram and all the tools mentioned to make my first couple of bucks online.
Whether it's an important consumer application, a specialist app to solve a particular niche problem, or even a time-wasting game you can play on your phone, you can create a massively successful business if you build software that helps people. (Look at the rise of Slack—the team communication software that went from side project to billion-dollar company in just 2 years.)
If you are a confident web developer then designing your own themes is an obvious path to follow if you are looking to make money online. ThemeForest sells a wide assortment of developers themes, including themes for WordPress, Shopify, Weebly, and Tumblr, to name a few. Once you have created your theme, get it accepted onto the ThemeForest marketplace and make money each time it sells.
Affiliate marketing has grown quickly since its inception. The e-commerce website, viewed as a marketing toy in the early days of the Internet, became an integrated part of the overall business plan and in some cases grew to a bigger business than the existing offline business. According to one report, the total sales amount generated through affiliate networks in 2006 was £2.16 billion in the United Kingdom alone. The estimates were £1.35 billion in sales in 2005.[19] MarketingSherpa's research team estimated that, in 2006, affiliates worldwide earned US$6.5 billion in bounty and commissions from a variety of sources in retail, personal finance, gaming and gambling, travel, telecom, education, publishing, and forms of lead generation other than contextual advertising programs.[20]
Thanks to the internet there's now a wide assortment of ways to make money online. So if you are stuck in a dead-end job and would like to change your life around then this guide will provide actionable strategies to enable you to do so. Whether you are looking for ways to make a bit of extra money, a part-time job or want to create a full-time income stream, there are plenty of opportunities to do so, all online and from the comfort of your own home.
There are a variety of tasks that you may be asked to perform. This can include delivering documents, delivering food or restaurant meals, taking pictures of a building for a real estate developer, taking pictures of a menu in an upscale restaurant, or even delivering auto-parts. If you have a good working car (or even a good bicycle), time on your hands, and a lot of energy, this can be a real opportunity to make money online.
Really good article with some great tips. Affiliate marketing has the potential to earn lots of money and I'm hoping I can make it happen. I have tried the matched betting and it DEFINITELY works. The one thing I would say is that you need to check that any bets have been accepted by the bookmaker. I have had on occasion bets which look like they have been accepted but don't register in my account. Always go into your account and check outstanding bets or your bet history.
The ClickBank Toolkit: Inside, you'll find all the tech providers, essential services and special deals you need to get up and running simple, quick and easy – all with "how-to" pdfs, checklists, videos and starter guides. You'll save huge amounts of time and money learning all the shortcuts and tricks to getting things done effectively (and often for free.)
One of the cool things about Google AdSense is that it's so easy to get set up. If you have a blog or website, you can sign up for a free Google AdSense Account. From there, Google will give you a unique code that you will paste onto your website. Google takes it from there, tracking your page views, traffic, and earnings on your behalf. There is no upkeep or maintenance to get this thing going, which makes it a no-brainer if you have a website already.
Then you need to use all available resources to drive traffic to the mini-guide. For people to have access to the guide, they must provide their e-mail address. The selling point for e-book history of ham comes at the end of the mini-guide. If your mini-guide has successfully awakened the interest of people, you'll have a good number of purchases. You also have your emails, and can be used to alert customers of other offers.
Do you love getting refunds? How cool would it be to get money back on stuff you've already bought? Paribus is a service that lets you find out if stores you've shopped at online owe you a refund. It's free to sign up. Paribus connects to your email account and checks your receipts. If they find out a retailer has dropped their price they file a price adjustment claim for you. Try out Paribus.
Etsy: While Etsy's popularity has declined recently, it's still a great resource for selling handmade items online. No need for complex ecommerce sites or merchant accounts or any sort of automation. The company takes a commission of every sale and charges a small listing fee per item. But many still use Etsy as their primary source of income. The best part is that you can also sell digital products on here such as poster designs.
So, where are we supposed to turn to make money the legitimate way online? This isn't just about generating passive income; this is also about finding ways and means to create an active income through the conveniences afforded to us by the internet that will not only help us with our debt obligations, but also empower us to save, invest and get really rich in the future.
So, where are we supposed to turn to make money the legitimate way online? This isn't just about generating passive income; this is also about finding ways and means to create an active income through the conveniences afforded to us by the internet that will not only help us with our debt obligations, but also empower us to save, invest and get really rich in the future.
Register in least 10 forums and try to post at least 100 comments in every forum. However, don't spam in the forum otherwise you account can get ban. If the forum is relevant to your product, you will surely earn commission in your first few days. Test the product if it is performing good, then post more comments, otherwise change the product and start promoting that one.
First off, I'm a blogger so it seems wrong not to mention it, but more importantly, it's a legitimate way to make money. It's quite possibly the least straight-forward way on this list, but it's very doable and it's also quite possibly the funnest way on this list. I love blogging and I know hundreds of bloggers who feel the same. So let's talk about making money blogging and what it really means.
In 2006, the most active sectors for affiliate marketing were the adult gambling, retail industries and file-sharing services.[21]:149–150 The three sectors expected to experience the greatest growth are the mobile phone, finance, and travel sectors.[21] Soon after these sectors came the entertainment (particularly gaming) and Internet-related services (particularly broadband) sectors. Also several of the affiliate solution providers expect to see increased interest from business-to-business marketers and advertisers in using affiliate marketing as part of their mix.[21]:149–150
Really good article with some great tips. Affiliate marketing has the potential to earn lots of money and I'm hoping I can make it happen. I have tried the matched betting and it DEFINITELY works. The one thing I would say is that you need to check that any bets have been accepted by the bookmaker. I have had on occasion bets which look like they have been accepted but don't register in my account. Always go into your account and check outstanding bets or your bet history.
Welcome to the lessons section where you get free and unlimited access to over 100 video tutorials with PDF lesson notes. Build your own website with our site building lessons, promote it using SEO and monetize it with affiliate marketing and PPC. Get exclusive interviews with internet gurus as they share their success stories on how they have earned millions online.
You can also market your ebook on your own website or blog, particularly if the site gets good traffic. Still another method is affiliate marketing. You can offer to pay sites related to your ebook a percentage of the sale price – say, anywhere between 20% and 50% – for them to post an ad or linked article for your book on their site. This could enable you to market your ebook on multiple platforms for greater market exposure.


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ALL who knew of this dastardly exploitation of those in his trust and HID IT OR DID NOTHING, when they should have, MUST be held accountable!
Excerpts from the Article:
Ohio State said Friday that an investigation had confirmed — in voluminous details gleaned from hundreds of interviews — that a team doctor had sexually abused at least 177 men, including many varsity athletes, while working for the university in the 1970s, '80s and '90s.
The university also revealed that dozens of Ohio State officials, including more than 50 athletic department staff members, were aware of the doctor's actions during his nearly two-decade tenure yet did not act to stop them.
In a 182-page report issued on Friday, Ohio State detailed how the doctor, Richard H. Strauss, had groped students, required them to strip unnecessarily during examinations, and asked intimate questions about sexual practices under the guise of providing medical treatment.
"The findings are shocking and painful to comprehend," the Ohio State president, Michael V. Drake, said in a statement.
"Our institution's fundamental failure at the time to prevent this abuse was unacceptable," he added, "as were the inadequate efforts to thoroughly investigate complaints raised by students and staff members."
The university said that college personnel knew about the accusations against Dr. Strauss, who committed suicide in 2005, as early as 1979. In fact, many former students interviewed for the report said they believed Dr. Strauss's actions were an "open secret" on campus and among athletes, coaches, trainers and other team physicians. But again and again, the report made clear, those in position to take action against Dr. Strauss seemed unwilling or unable to intervene.
Some of those interviewed, for example, said there was much talk about Dr. Strauss's tendency to shower with students, sometimes several times a day, and to loiter in the locker room area. Two students said that their reports of abuse had been relayed to higher authorities in the athletic department, including at least two former athletic directors.
But the report also revealed that a "self-described" investigation in 1994 by Ohio State's director of sports medicine, Dr. John Lombardo, dismissed accusations against Dr. Strauss as "unfounded rumors." Dr. Lombardo, who said he had conducted the investigation after a former fencing coach had raised concerns about Dr. Strauss's interactions with fencers, declined to be interviewed by the investigators.
The report released Friday was based on a yearlong investigation by Perkins Coie, a law firm that said it had conducted more than 500 interviews. "With rare exceptions, we found the survivor accounts concerning their experiences with Strauss to be both highly credible and cross-corroborative," the report said.
There are numerous lawsuits pending against the university from victims of Dr. Strauss.
The Whole Story:


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