NREM Sleep Boosts Cognitive Performance by Desynchronizing Brain Circuits

Sleep is known to enhance cognition, but its neural mechanisms remain unclear. A new study reveals that non-rapid eye movement (NREM) sleep improves behavioral performance by inducing cortical desynchronization. Using multielectrode recordings in macaques performing a visual discrimination task, researchers observed that while sleep initially synchronizes neuronal activity, post-sleep neural firing becomes more desynchronized, correlating with enhanced information encoding and improved task performance. Notably, low-frequency electrical stimulation (4 Hz) of the visual cortex replicated these cognitive benefits, suggesting a causal relationship. Computational models further linked these effects to an asymmetric decrease in intracortical synaptic conductance, particularly in inhibitory synapses. This research sheds light on how sleep restructures brain activity to optimize learning and perception, with potential implications for neuromodulation therapies.