The significance of frontal system disorders for medical practice and health policy.

In major chronic diseases, apathy or impaired executive cognitive function (ECF) can reduce the patient's ability to cope with the disease and its treatment and to maintain personal safety, dignity, and goal-directed activity. Psychometric and imaging studies support a causal role for frontal system dysfunction. The view that frontal system dysfunction mediates or aggravates disability in a wide range of psychiatric and nonpsychiatric disorders 1) motivates further research on how ECF deficits interact with specific physical impairments to produce disability; 2) supports policies that base entitlements to care on ECF impairments; and 3) suggests the need for a vigorous search for drugs that prevent or palliate prefrontal dysfunction, especially the syndromes of apathy and impaired ECF.