APOE moderates compensatory recruitment of neuronal resources during working memory processing in healthy older adults

作者：Scheller Elisa^*; Peter Jessica; Schumacher Lena V; Lahr Jacob; Mader Irina; Kaller Christoph P; Kloeppel Stefan

来源：Neurobiology of Aging, 2017, 56: 127-137.

DOI：10.1016/j.neurobiolaging.2017.04.015

• Functional magnetic resonance imaging
• Aging
• APOE
• Neuronal compensation
• Working memory
• Multiple regression
• Moderator analysis

The APOE epsilon 4 allele increases the risk for sporadic Alzheimer's disease and modifies brain activation patterns of numerous cognitive domains. We assessed cognitively intact older adults with a letter n-back task to determine if previously observed increases in epsilon 4 carriers' working-memory-related brain activation are compensatory such that they serve to maintain working memory function. Using multiple regression models, we identified interactions of APOE variant and age in bilateral hippocampus independently from task performance: epsilon 4 carriers only showed a decrease in activation with increasing age, suggesting high sensitivity of fMRI data for detecting changes in Alzheimer's diseaseerelevant brain areas before cognitive decline. Moreover, we identified epsilon 4 carriers to show higher activations in task-negative medial and task-positive inferior frontal areas along with better performance under high working memory load relative to non-epsilon 4 carriers. The increased frontal recruitment is compatible with models of neuronal compensation, extends on existing evidence, and suggests that epsilon 4 carriers require additional neuronal resources to successfully perform a demanding working memory task.

• 出版日期2017-8