Agraphia consists of many different kinds. They can be divided into two major subsections: central versus peripheral. Central refers to the linguistic agraphias; so these include lexical, phonological, deep, and semantic agraphia. Peripheral refers to the non-linguistic agraphias; this includes allographic, apraxic, motor execution, hemianoptic and afferent agraphia. [1]

Causes edit

Agraphia has a multitude of causes ranging from strokes, lesions, traumatic brain injury, and dementia. Research up to this point has found twelve regions of the brain that are associated with handwriting. [2] 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. [2]

Agraphia In Alzheimer's Disease edit

Writing disorders are often an early manifestation of Alzheimer's Disease (AD).[3] In many early AD patients, the first sign pertaining to writing skills is the selective syntactic simplification of their writing. Patients will write will less description, detail and complexity. Other markers will emerge, such as grammatical errors that were not previously made. Evidence shows that AD patients develop different agraphias as AD progresses. Towards the beginning stages of AD, patients show signs of allographic agraphia and apraxic agraphia. Allographic agraphia is represented in AD patients by the mixing of lower and upper case letters in words; apraxic agraphia 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 agraphia. They begin to form spatial agraphia, which is the inability to write in a straight horizontal line, and there are often unnecessary gaps between letters and words. [3]

An interesting connection that can be made between AD and agraphia is the role of memory in normal writing ability and how that may be affected with the onset of AD. [4] Normal spellers have access to a system that uses a whole-word retrieval process; this system is called the lexical spelling system. This system, when functioning properly, allows for people to recall 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. In cases when the spelling system cannot be used, such as with unfamiliar words, non-words or words that we do not recognize the spelling for, people use the phonological spelling system. This system is what we use to sound out a word and spell it using the knowledge we have regarding what letters create what sounds. In AD patients, these memory stores that are employed for every day handwriting become lost as the degenerative disease progresses. This relatively simple connection helps explain how dementia can lead to agraphia. [4]

Management edit

Agraphia is a disorder that cannot be directly treated; however, patients can be rehabilitated to regain some of their previous writing abilities.

Lexical Agraphia edit

The Copy and Recall Treatment (CART) method helps to reestablish the ability to spell specific words that are learned through repeated copying and recall of these target words. [5]

Another management method is referred to as T-CART and follows the same pattern with the use of technology. This rehabilitation is typically done through the use of computers or texting. This allows the patient to type instead of writing words. It has been found that both CART and T-CART have similar rates of success in the patient's learning to spell the target words; however, CART has a longer memory duration for the learned words. This is because the motor movements for T-CART only require the spatial location of the keyboard, whereas CART requires the motor movement to form each individual letter as it is written. [6]

The problem solving approach is used as a self-correcting method of phonological errors. The patient sounds out the word and attempts to spell it. These patients typically employ the use of an electronic dictionary-type device that they can type their spelling of the word into and if it is incorrect, the device offers suggestions and can say the correct word back to the patient. This method takes advantage of the preserved sound-to-letter correspondences that some patients still have intact. [5]

Phonological Agraphia edit

For the management of phonological agraphia, patients are trained to memorize key words, such as a familiar name or object for which they will always remember the word, that can then help them form the grapheme for that phoneme. [5]

Deep Agraphia edit

The Anagram and Copy Treatment (ACT) uses the arrangement of component letters of target words and then repeated copying of the target word. This is similar to the CART in its recall and copy method, the primary different being that the target words for ACT are ones that are specific to that patient so they will be practiced and remembered. It is necessary to emphasize target words that are important in the life of the patient because deep agraphia patients do not typically have the same memory for the words as other agraphia patients may. [5]

Graphemic Buffer Agraphia edit

This employs the training of specific words to improve spelling. The patient will use cueing hierarchies and copy and recall method of specific words to work them into their short term memory loop, or graphemic buffer. The segmentation of longer words into shorter syllable segments helps bring words into their short term memory as well. [5]

Allographic Agraphia edit

Management of allographic agraphia can be as simple as having a card with the alphabet on it so the patient can write legibly by copying the correct letter shapes provided. [5]

Apraxic Agraphia edit

There are few rehabilitating methods for apraxic agraphia; however, if the patient has considerably better hand control and movement with typing than they do with handwriting, then they can employ the use of technology. Texting and typing do not require the same technical movements that handwriting does; for these technological methods, only spatial location of the fingers to type is required. [5]

Micrographia edit

This is a condition that can occur with the development of other disorders, such as Parkinson's Disease, and is when handwriting becomes illegible because of how small the writing is [1]. For some patients, a simple command to write bigger succeeds in eliminating the issue. [5]

  1. ^ a b Marien, Peter (2013). ""Apraxic dysgraphia" in a 15-Year-Old Left-Handed Patient: Disruption of the Cerebello-Cerebral Network Involved in the Planning and Execution of Graphomotor Movements". Cerebellum. 12 (1): 131–139. doi:10.1007/s12311-012-0395-1. PMID 22752975. S2CID 255582456. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  2. ^ a b Planton, Samuel (2013). "The "handwriting brain": A meta-analysis of neuroimaging studies of motor versus orthographic processes". Cortex. 1 (16): 1–16. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  3. ^ a b Croisile, Bernard (1999). "Agraphia in Alzheimer's disease". Dementia and Geriatric Cognitive Disorders. 10 (3): 226–230. doi:10.1159/000017124. PMID 10325451. S2CID 22746928. {{cite journal}}: Unknown parameter |month= ignored (help)
  4. ^ a b Neils-Strunjas, Jean (Dec 2006). "Dysgraphia in Alzheimer's Disease: A Review for Clinical and Research Purposes". Journal of Speech, Language, and Hearing Research. 49 (6): 1313–1330. doi:10.1044/1092-4388(2006/094). PMID 17197498. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)CS1 maint: date and year (link)
  5. ^ a b c d e f g h Beeson, Pelagie M. (Winter 2004). "Remediation of Written Language". Top Stroke Rehabil. 11 (1): 37–48. doi:10.1310/D4AM-XY9Y-QDFT-YUR0. PMID 14872398. S2CID 7128937.{{cite journal}}: CS1 maint: date and year (link)
  6. ^ Beeson, Pelagie M. (June 2013). "Writing treatment for aphasia: a texting approach". Journal of Speech, Language and Hearing Research. 56 (3): 945–955. doi:10.1044/1092-4388(2012/11-0360). PMC 3929384. PMID 23811474. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)CS1 maint: date and year (link)