Topological changes of the effective connectivity during the working memory training

Working memory (WM) refers to the retention of information over a short period of time. Accumulated evidence showed that training WM would lead to beneficial effects in untrained tasks, which could be attributed to the strengthening of the functional connections between brain regions through repeated training task. In this proof of concept investigation, we applied a graph theoretical approach to analyze the early changes of functional connectivity from two subjects undergoing a spatial n-back WM training task for three continuous days. A significant decreased clustering coefficient and normalized shortest path length was revealed, suggesting a reduced local efficiency with an increased global efficiency after WM training. Our findings thereby provide insightful implications for understanding the mechanisms of brain dynamics in cognitive training.