Prefrontal cortical plasticity during learning of cognitive tasks

• Published in: Nature communications 2022-01, Vol.13 (1), p.90-12, Article 90
• Main Authors: Tang, Hua, Riley, Mitchell R., Singh, Balbir, Qi, Xue-Lian, Blake, David T., Constantinidis, Christos
• Format: Article
• Language: English
• Subjects: 631/378/1595/1636; 631/378/2649/2150; 9/30; 9/97; Action Potentials - physiology; Animals; Banded structure; Cognition - physiology; Cognitive ability; Cognitive tasks; Control tasks; Electrodes; Electrodes, Implanted; Firing rate; Frequencies; Humanities and Social Sciences; Laboratories; Learning; Macaca mulatta; Male; Memory; Memory tasks; Memory, Short-Term - physiology; Mental task performance; multidisciplinary; Neurons; Neurons - cytology; Neurons - physiology; Neuroplasticity; Neurosciences; Prefrontal cortex; Prefrontal Cortex - anatomy & histology; Prefrontal Cortex - physiology; Science; Science (multidisciplinary); Short term memory; Stereotaxic Techniques; Training; Unit activity
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-021-27695-6

Training in working memory tasks is associated with lasting changes in prefrontal cortical activity. To assess the neural activity changes induced by training, we recorded single units, multi-unit activity (MUA) and local field potentials (LFP) with chronic electrode arrays implanted in the prefrontal cortex of two monkeys, throughout the period they were trained to perform cognitive tasks. Mastering different task phases was associated with distinct changes in neural activity, which included recruitment of larger numbers of neurons, increases or decreases of their firing rate, changes in the correlation structure between neurons, and redistribution of power across LFP frequency bands. In every training phase, changes induced by the actively learned task were also observed in a control task, which remained the same across the training period. Our results reveal how learning to perform cognitive tasks induces plasticity of prefrontal cortical activity, and how activity changes may generalize between tasks. It remains unclear whether improvements in one cognitive task transfer to other tasks. Here, the authors show that changes in prefrontal neuronal activation, firing rate, and local field potentials induced during active learning of a working memory task are also evident in a control task.