Improved Mood Boosts Memory Training Gains in Older Adults With Subjective Memory Complaints via Enhanced Amygdala-hippocampal Connectivity

Objective: Older adults with subjective memory complaints (SMC) have a higher risk of dementia and commonly demonstrate symptoms of anxiety. This study examined the neural correlates of group counseling (GC)-boosted memory training (MT) gains. Design: This study was an active, controlled, randomized trial. Setting: Neighborhoods near the Institute of Psychology of the Chinese Academy of Sciences (CAS). Participants: Community-dwelling older adults, aged 60 or above with a minimum of 6 years of education, were recruited through advertisements and flyers posted at community service stations. Measurements: The amplitude of low-frequency fluctuations and resting-state functional connectivity (rs-FC) analyses were used to examine the neural correlates associated with MT gains enhanced by improved mood in older adults with SMC. Participants were randomly assigned to the combined intervention (CI) or GC group. The CI group received 3 weeks of GC followed by 4 weeks of MT, and the GC group received GC and health lectures. Cognitive function and emotions were assessed before GC (T1), after GC (T2), and after MT (T3). Both groups underwent resting-state functional magnetic resonance imaging scanning at T2 and T3. Results: Alleviated anxiety was positively correlated with rs-FC between the amygdala and left hippocampus and negatively correlated with rs-FC between the amygdala and right hippocampus. MT improvement was negatively correlated with rs-FC between the amygdala and right hippocampus in the CI group; the correlation was not significant after controlling for emotional changes. Conclusions: Amygdala-hippocampal connectivity may be associated with improved mood-enhanced MT gains in individuals with SMC.