Micrographia is an acquired disorder that features abnormally small, cramped handwriting or the progression to progressively smaller handwriting. It is commonly associated with neurodegenerative disorders of the basal ganglia, such as in Parkinson's disease, but it has also been ascribed to subcortical focal lesions. O'Sullivan and Schmitz describe it as an abnormally small handwriting that is difficult to read, as seen in the photo to the right. Micrographia is also seen in patients with Wilson's disease, Obsessive Compulsive Disorder, Metamorphopsia, or with isolated focal lesions of the midbrain or basal ganglia.
A common feature of Parkinson's disease (PD) is difficulty in routine activities due to lack of motor control. More specifically, patients have difficulty maintaining the scale of movements and have reduced amplitude of movement; also known as hypokinesia. These difficulties with scaling and controlling the amplitude of movement cause patients with PD to have difficulty with complex, sequential movements. This helps to explain why micrographia is a common symptom of the disease. Another reason is a lack of physical dexterity.
James Parkinson may have been aware of micrographia in patients with shaking palsy (later renamed Parkinson's disease), when he described "the hand failing to answer with exactness to the dictates of the will".
Occurrence in Parkinson's
Micrographia is seen in 9 to 75% of PD patients and often appears before other cognitive symptoms.
Micrographia may worsen when a PD patient is under-medicated or when the effects of the medication are wearing off.
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