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StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-.
Franklyn Rocha Cabrero ; Orlando De Jesus .
Last Update: September 30, 2022 .
Dysgraphia is defined as a difficulty or inability to communicate clearly and correctly through written language. This evaluation requires adjustment to the patient's age and education. Syntax errors, ineligible handwriting, odd spelling, and inaccurate word production are common. Writing is a complex task that requires exquisite coordination of higher levels of complex cognitive domains, including expressive language and fine motor skills.
Dysgraphia is usually associated with multiple cortical and subcortical damage in the functional language regions. Multiple bi-hemispheric cortical networks produce written language, including the anterior cingulate, supramarginal, and frontal gyrus. The functional areas include the left supero-frontal sulcus/middle frontal gyrus, the left supero-parietal lobule, the left inferior parietal lobule, the angular gyrus, the primary motor cortex, and the somatosensory cortex. Other associated areas include the right anterior and posterior cerebellum, the left posterior nucleus of the thalamus, the left inferior frontal gyrus, the right superior frontal cortex, the right inferior parietal lobule, the left fusiform gyrus, and the left putamen. Agraphia is a complete impairment when it comes to writing correctly. Different types of agraphia can result from brain damage in multiple cortical and subcortical regions of the central nervous system.[1][2][3][4][5]
Types of Agraphia
Deep agraphia affects orthographic memory and phonology production, leading to semantic errors. It is associated with left parietal lobe damage.[6][7]
Peripheral agraphia is the inability to connect letters to form words and full sentences; visual misperception is another manifestation. It can be associated with temporal atrophy and temporal lobe neurodegeneration.[8][9][10]
Lexical agraphia- inability to spell irregular words.[11][12][13]Alexia, with agraphia, cannot read and write, and the patient cannot retrieve orthographic memory. It is attributable to frontal lobe and thalamic damage.[14][15][16][17]
Phonological agraphia- inability to sound out a word, difficulties with writing abstract thoughts more than concrete thoughts. It appears to be caused by left-hemispheric damage.[18][19][20][21]
Reiterative or repetitive agraphia-affected individuals tend to repeat letters or words as they write.[18]
Apraxic or pure agraphia-inability produces written language with preserved reading and speaking. Associated with frontoparietal, frontotemporal, and thalamic structure damage.[22][23][24][25]
Visuospatial agraphia-inability to organize the letters of a word in a sentence correctly (spacial semantic errors), sometimes can lead to vertical writing or writing that focuses on 1 area of a page. Related to the damage to the right hemisphere (middle cerebral artery territory).[26][27]
Dysexecutive agraphia- inability to organize planned thoughts in written language. Associated with neurodegenerative disorders (frontotemporal dementia, Parkinson disease) usually involving the frontal lobes.[27][28]
Musical agraphia- inability to write musical language (disrupting creativity) because of traumatic brain injury.[29][30]
Other manifestations include Gerstmann syndrome-finger agnosia (inability to recognize fingers), right-left confusion, agraphia, and acalculia (inability to perform simple math operations). It is related to the damage to the dominant left angular gyrus.[31][32][33]
Causes of Agraphia
