The clock drawing test as a measure of executive dysfunction in elderly depressed patients.

The aims of this research were to determine whether performance on the Clock Drawing Test (CDT) could accurately distinguish between older patients with depression and older patients with depression and previously undocumented executive dysfunction and to determine if there was a correlation between CDT and depression severity. The authors studied 52 patients consecutively admitted to a geriatric psychiatry inpatient unit of a university hospital who met DSM-IV criteria for major depression or depression not otherwise specified but had no concurrent diagnosis of dementia. All the subjects completed the Mini-Mental State Examination (MMSE), Mattis Dementia Rating Scale (DRS), and the CDT, as well as the Geriatric Depression Scale (GDS). The patients were divided into 2 subgroups based on the DRS score: <129 (cognitive impairment) versus = 129. Results indicated that the depressed patients with a score of DRS <129 had significantly lower CDT scores than did patients with DRS = 129 and normal comparison subjects (P< .01). The results support the hypothesis that CDT score is lower in elderly depressed patients with executive dysfunction versus nondepressed seniors as well as depressed patients without executive dysfunction.

The influence of cognitive reserve on memory following electroconvulsive therapy.

Cognitive reserve (CR) theory proposes that certain genetic and nonacquired variables, such as larger head size and greater neuronal density, and some life experiences, such as higher educational and occupational attainment, provide a buffer against brain dysfunction in the face of acquired central nervous system (CNS) dysfunction. This study examined CR in the pseudoexperimental paradigm of electroconvulsive therapy (ECT). Subjects included fifty (N = 50) depressed patients treated with bilateral ECT. Subjects were placed in high (n = 27) or low (n = 23) CR groups based on years of education and occupational attainment. At baseline, no significant differences were observed between the groups in the amount of information forgotten on a verbal memory measure (Randt stories) after a 30-minute delay. Following three ECT treatments, however, the high CR group forgot significantly less information after a 30-minute delay, as compared to the low CR group (p < 0.01). These data provide further support for CR theory and suggest that CR may be an underlying factor in differential memory loss in ECT.