To illustrate the utility of the twin method in Alzheimer's disease (AD) research, we studied in detail a pair of monozygotic twins concordant for the disease but markedly different in their clinical presentations. Neuropsychological evaluation, magnetic resonance brain imaging, and cerebral glucose metabolic studies revealed a typical behavioral presentation for AD in Twin A. In contrast, Twin B showed prominent visuospatial impairments. Although there was no identified cause for the disparate presentations, a close correspondence was observed between the neuropsychological findings and the regional brain measures. The results suggest that the trajectory of AD may vary widely even in genetically identical individuals. Factors accounting for the variability include potential intrauterine, early developmental, and environmental differences.
ASJC Scopus subject areas
- Neuropsychology and Physiological Psychology