Karbach, J. & Brieber, S.
Department of Psychology. Saarland University. Saarbrücken, Germany
Although a number of behavioral studies have shown that executive control training can transfer to new untrained tasks, little is known about the underlying mechanisms and the associated changes in functional brain activity. Previous studies have yielded mixed results, including patterns of increases, decreases, and functional reorganization of regional activations after training. The aim of this study was to investigate qualitative and quantitative changes in neural activity associated with the transfer of task-switching training. We assessed 31 young adults in a pretest-training-posttest design. Both pretest and posttest included functional neuroimaging (fMRI) while participants performed task switching and working memory tasks. After the pretest, participants were randomly assigned to a training condition (n=16) or an inactive control condition (n=15). The training group performed five sessions of task-switching training. Behavioral data showed training-related benefits on the switching task as well as transfer of training to a similar new switching task and a working memory task. Neuroimaging data revealed reduced activity in prefrontal and superior parietal areas after the training, pointing to increased neural efficiency. Consistent with previous findings, the training also resulted in increased activity in the striatum, suggesting that it plays an important role in mediating learning and transfer effects.