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BRAIN ACTIVITY AND CONNECTIVITY IN 11C-PIB PET MCI AND HEALTHY ELDERLY INDIVIDUALS AFTER COGNITIVE TRAINING

Background: Cognitive training (CT) can benefit mild cognitive impairment (MCI) people. However, no study has explored its effects in MCI patients with amyloid biomarkers. Objectives: to investigate brain correlates and connectivity after CT in MCI patients with 11C-PIB PET+/- and healthy controls (HC). Methods: 25 participants PIB+ (n=8), PIB- (n=8) and HC (n=9) were included. They underwent 6 sessions of CT using visual imagery to recall newspaper reports and scanned with fMRI before and after CT using a newspaper encoding paradigm. We used 3TMR, FSL, one seed in the right and in the left hippocampus for resting state. Results: Before CT, all participants showed activation in the left precentral and fusiform gyrus, bilateral occipital cortex and cerebellum (Fig 1-A). HC and PIB- individuals showed left hippocampus, inferior frontal gyrus and intraparietal cortex activation. After CT, HC showed bilateral hippocampus activation (Fig 1-B), PIB+ had a new cluster of activation in left hippocampus. HC showed increased connectivity between right hippocampus and left parietal, pre and post-central gyri (Fig 1-C). Conclusions: There were different brain beneficial effects of CT with bilateral hippocampus recruitment for HC and in the left hemisphere for PIB+. These findings may suggest specific functional compensation mechanisms related to CT in this population.