Epidemiologic evidence suggests that individuals with higher IQ, education, occupational attainment, or participation in leisure activities have a reduced risk of developing Alzheimer disease (AD). The concept of cognitive reserve (CR) posits that individual differences in how tasks are processed provide differential reserve against brain pathology or age-related changes. This may take 2 forms. In neural reserve, preexisting brain networks that are more efficient or have greater capacity may be less susceptible to disruption. In neural compensation, alternate networks may compensate for pathology's disruption of preexisting networks. Imaging studies have begun to identify the neural substrate of CR. Because CR may modulate the clinical expression of AD pathology, it is an important consideration in studies of “preclinical” AD and treatment studies. There is also the possibility that directly enhancing CR may help forestall the diagnosis of AD.
Cognitive Neuroscience Division of the Taub Institute, New York, NY
Departments of Neurology and Psychiatry, Columbia University College of Physicians and Surgeons, New York, NY
Supported by a grant from the National Institutes on Aging (RO1 AG26158).
Reprints: Yaakov Stern, Taub Institute, 630 W 168th Street, New York, NY 10032 (e-mail: firstname.lastname@example.org).
Received for publication January 4, 2006; accepted February 25, 2006