Basal Ganglia Disease And Depression

Abstract

Abstract Diseases of the basal ganglia are quintessential neuropsychiatric disorders, characterized by abnormal movements, cognitive impairment, and psychiatric symptoms and signs. Depression is common in these illnesses and may occur at presentation or during the course of the illness. Individuals may present to the psychiatrist before seeing a neurologist. Depression is an important target for research, as it affords a unique perspective on the pathophysiology of basal ganglia diseases as well as an alternative method of understanding the biology of mood disorders. Traditionally, basal ganglia diseases are diagnosed and treated by neurologists, who define their onset by specific motor manifestations. Psychiatric symptomatology has been considered peripheral to the understanding of the motor disorders that define basal ganglia diseases. There is growing evidence for the contrary view that mood and affect are integrally related to the evolution of these diseases. For example, in diseases such as Huntington’s disease or Wilson’s disease, where the genetic mutation has been identified, it is possible to identify presymptomatic individuals, prior to the development of motor signs, who are unaware of their genetic status, and determine whether cognitive or psychiatric manifestations occur more often in gene-positive than in genenegative individuals. Another way to examine the role of psychiatric impairment is to study individuals in the general population who have undergone psychiatric assessments and to determine if individuals with a history of affective disorder are more likely to develop specific basal ganglia diseases (e.g., Parkinson’s disease) than individuals without mood disorders. This chapter includes a review of the epidemiology, prevalence, and correlates of depression in basal ganglia diseases and their treatment.