Affiliations: Veterans Affairs San Diego Healthcare System, San
Diego, CA, USA | Department of Psychiatry, University of California San
Diego, San Diego, CA, USA | Department of Neurosciences, University of California
San Diego, San Diego, CA, USA | Department of Radiology, University of California San
Diego, San Diego, CA, USA
Note: [] Corresponding author: Mark W. Jacobson, Ph.D., Veterans Affairs
Medical Center San Diego, Dept. 151B, 3350 La Jolla Village Dr., San Diego, CA
92151, USA. Tel.: +1 858 642 3765; Fax: +1 858 642 6393; E-mail:
mjacobson@vapop.ucsd.edu
Abstract: Identifying a preclinical phase of Alzheimer's Disease (PCAD) that
is distinct from cognitive changes in healthy aging continues to be a major
research focus. Combining neuropsychological and neuroimaging methodologies
should improve our ability to differentiate healthy from pathological aging,
although studies that utilize both methods often result in equivocal findings,
possibly due to variability in cognitive test performance that may be capturing
distinct phenotypes. One method of capturing this cognitive variability is to
utilize contrasting neuropsychological tests to identify subgroups
representative of distinct cognitive phenotypes, and determine whether
differences in brain morphometry support these classifications. We review
several approaches to defining cognitive subgroups, and we consider the
possibility that cognitive asymmetry might provide one means of identifying
both functional and structural changes associated with aging and dementia.
