Dorsolateral prefrontal functional connectivity predicts transfer of working memory gains after cognitive training

Abstract

AbstractBackgroundNormal aging is associated with working memory decline. A decrease in working memory performance is associated with age‐related changes in functional activation patterns in the dorsolateral prefrontal cortex (DLPFC). Cognitive training can improve cognitive performance in healthy older adults. We implemented a cognitive training study to assess determinants of transfer of gains to untrained tasks, a key indicator for the effectiveness of cognitive training. We aimed to investigate the association of resting‐state functional connectivity of DLPFC with working memory performance improvement and successful transfer of gains after training.MethodA sample of 60 healthy older adults (mean age: 68 years) underwent a 4‐week cognitive training of working memory. Baseline resting‐state functional magnetic resonance imaging in order to investigate the functional connectivity of DLPFC. To evaluate transfer and training effects, participants underwent a neuropsychological assessment before and after the training. A second follow‐up assessment was applied 12 weeks after the training. We used cognitive scores of Digit span backwards and Visual block span backwards tasks representing working memory function. The training group was divided in subjects who had and who did not have successful transfer, which was defined as higher improvement in working memory tasks than the control group.ResultA high functional connectivity of DLPFC of the right hemisphere was a significantly associated with successful transfer of gains and performance improvement in the visuospatial task. Transfer effects were limited and maintenance of gains was restricted to the time period directly after the training. The training group showed performance improvement in the Digit span backwards task.ConclusionFunctional activation patterns of DLPFC during visuospatial task contribute to successful transfer and performance improvement. Even though transfer is possible in aging, it remains limited.