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.