Neuropsychiatric Manifestations of Amyotrophic Lateral Sclerosis

Neuropsychiatric manifestations are observed in a significant proportion of patients with amyotrophic lateral sclerosis (ALS). Severe behavioral disorders develop when ALS is combined with frontotemporal dementia, and this is regarded as a single continuum. Mental disorders are less marked in ALS with predominantly motor manifestations and most frequently consist of apathy. Depending on etiology, mental disorders in ALS can be psychogenic, reflecting the patient’s response to serious illness, or organic, developing as a result of degeneration and disconnection of fronto-subcortical and fronto-temporal connections. An important role in the development of mental disorders in ALS is played by various genetic factors, in particular, the occurrence of hexanucleotide expansion in the C9orf72 gene. In ALS without dementia, especially in the first months after diagnosis, there is a high risk of developing depressive disorders, which in severe cases can lead to suicide. Further research is needed in this direction.