Man Hand Holding Compass in Mountains. Joshua Woroniecki (CC0)
Learning new cognitive skills, such as navigating an unfamiliar city or remembering long lists of words, is a fundamental part of daily life. Yet, scientists still do not fully understand how the brain changes as these skills are acquired. Previous studies have often focused on experts, like London taxi drivers or memory champions, whose brains may have developed structural differences over many years of training. But it remains unclear how short-term training affects the brains of typical healthy adults.
To explore this question, Zheng et al. designed two intensive training programs that lasted for several weeks. One taught people how to navigate complex virtual environments, and the other trained them to remember long sequences of words. Young adults completed brain scans before and after the training. The researchers then measured brain structures (such as the size of the hippocampus, a region important for memory and navigation) and assessed how different brain regions interacted during cognitive tasks.
The results revealed that participants became significantly better at skills they had practiced, showing faster learning and improved performance. However, their brain structure did not change; there were no differences in hippocampal volume, cortical thickness, or the microstructure of white matter pathways. Instead, the most noticeable changes occurred in how brain regions communicated with one another during memory and navigation tasks. Networks of brain regions reorganized their patterns of activity, especially in areas involved in cognitive control, suggesting that the brain adapts to new challenges primarily by altering how its existing circuits work together rather than by growing new tissue.
These findings reveal that, at least in the early stages of learning complex skills, the brain’s functional networks are more flexible and responsive than its physical structure. This insight could help inform the design of cognitive training programs and rehabilitation strategies by highlighting the importance of targeting dynamic brain activity rather than structural changes.
