<unk>  has a multitude of causes ranging from strokes, lesions, traumatic brain injury, and dementia. Twelve regions of the brain are associated with handwriting. The four distinct functional areas are the left superior frontal area composed of the middle frontal gyrus and the superior frontal sulcus, the left superior parietal area composed of the inferior parietal lobule, the superior parietal lobule and the intraparietal sulcus and lastly the primary motor cortex and the somatosensory cortex. The eight other areas are considered associative areas and are the right anterior cerebellum, the left posterior nucleus of the thalamus, the left inferior frontal gyrus, the right posterior cerebellum, the right superior frontal cortex, the right inferior parietal lobule, the left fusiform gyrus and the left putamen. The specific type of<unk>  resulting from brain damage will depend on which area of the brain was damaged. Diagram of human brain showing surface gyri and the primary auditory cortex Phonological<unk>  is linked to damage in areas of the brain involved in phonological processing skills (sounding out words), specifically the language areas around the sylvian fissure, such as Broca's area, Wernicke's area, and the supramarginal gyrus. Lexical<unk>  is associated with damage to the left angular gyrus and/or posterior temporal cortex. The damage is typically posterior and inferior to the perisylvian language areas. Deep<unk>  involves damage to the same areas of the brain as lexical<unk>  plus some damage to the perisylvian language areas as well. More extensive left hemisphere damage can lead to global<unk> . Gerstmann's syndrome is caused by a lesion of the dominant (usually the left) parietal lobe, usually an angular gyrus lesion. Apraxic<unk>  with ideomotor apraxia is typically caused by damage to the superior parietal lobe (where graphomotor plans are stored) or the premotor cortex (where the plans are converted into motor commands). Additionally, some individuals with cerebellar lesions (more typically associated with non-apraxic motor dysfunction) develop apraxic<unk> . Apraxic<unk>  without ideomotor apraxia may be caused by damage to either of the parietal lobes, the dominant frontal lobe, or to the dominant thalamus. Visuospatial<unk>  typically has a right hemisphere pathology. Damage to the right frontal area of the brain may cause more motor defects, whereas damage to the posterior part of the right hemisphere leads predominantly to spatial defects in writing. Alzheimer's disease<unk>  is often seen in association with Alzheimer's disease (AD). Writing disorders can be an early manifestation of AD. In individuals with AD, the first sign pertaining to writing skills is the selective syntactic simplification of their writing. Individuals will write with less description, detail and complexity, and other markers, such as grammatical errors, may emerge. Different<unk> s may develop as AD progresses. In the beginning stages of AD, individuals show signs of allographic<unk>  and apraxic<unk> . Allographic<unk>  is represented in AD individuals by the mixing of lower and upper case letters in words; apraxic<unk>  is represented in AD patients through poorly constructed or illegible letters and omission or over repetition of letter strokes. As their AD progresses, so does the severity of their<unk> ; they may begin to form spatial<unk> , which is the inability to write in a straight horizontal line, and there are often unnecessary gaps between letters and words. A connection between AD and<unk>  is the role of memory in normal writing ability. Normal spellers have access to a lexical spelling system that uses a whole-word; when functioning properly, it allows for recall of the spelling of a complete word, not as individual letters or sounds. This system further uses an internal memory store where the spellings of hundreds of words are kept. This is called the graphemic output lexicon and is aptly named in relation to the graphemic buffer, which is the short term memory loop for many of the functions involved in handwriting. When the spelling system cannot be used, such as with unfamiliar words, non-words or words that we do not recognize the spelling for, some people are able to use the phonological process called the sub-lexical spelling system. This system is used to sound out a word and spell it. In AD individuals, memory stores that are used for everyday handwriting are lost as the disease progresses.
Agraphia
Bugchasing
Zeism
Voyeurism
Lordosis behavior
Latrodectism
Cheesewiring
Psychodrama