Reminisce to Rev-Up the Brain

Neuroimaging studies showing that default network activation interferes with complex mental tasks – but in most, the mental processes associated with default network conflict with task goals.  To overcome this predicament, Nathan Spreng, from Cornell University (New York, USA), and colleagues developed a new approach in which off-task processes such as reminiscing can support rather than conflict with the aims of the experimental task. Their novel task, “famous faces n-back,” tests whether accessing long-term memory about famous people, which typically engages default network brain regions, can support short-term memory performance, which typically engages executive control regions. While undergoing brain scanning, 36 young adults viewed sets of famous and anonymous faces in sequence and were asked to identify whether the current face matched the one presented two faces back. The team found participants were faster and more accurate when matching famous faces than when matching anonymous faces and that this better short-term memory performance was associated with greater activity in the default network. Observing that: “The results suggest that activation of the default network can contribute to task performance during an externally directed executive control task,” the study authors submit that: “Our findings provide evidence that successful activation of the default network in a contextually relevant manner facilitates goal-directed cognition.”