[Amyotrophic lateral sclerosis with dementia-neuropsychological aspect]

Amyotrophic lateral sclerosis (ALS) with dementia (ALS-D) is characterized clinically by frontal and neurological signs and symptoms, and pathologically by localized atrophy of front-temporal lobes and neuronal ubiquitin-positive inclusion. In this paper, we reviewed the neuropsychological findings of ALS-D. ALS-D is known to exhibit characteristics of fronto-temporal dementia. However, in clinical situations, it is often difficult to evaluate their cognitive functions due to impaired voluntary speech and physical disabilities. In order to identify characteristic and diagnostic cognitive symptoms of relatively advanced ALS-D patients, we reviewed the clinical features of recent studies of clinically definitive ALS Patients who had dementia, impaired voluntary speech, and physical disability. Their medical records showed that the patients made writing errors, and some of the patients demonstrated anosognosia. The writing errors of these cases consisted of paragraphia such as substitution, omission, or syntactic errors and individual differences in error types. We emphasize that aphasic writing errors have been underestimated, particularly in ALS-D patients with impaired voluntary speech. We also emphasize that anosognosia is one of the important symptoms in ALS-D. The relationship between writing errors and anosognosia should be investigated further.