Nucleus Basalis Stimulation Stabilizes Attractor Networks and Enhances Task Representation in Prefrontal Cortex

The action of acetylcholine in the neocortex is critical for executive function. Cholinergic drugs can improve cognitive function in patient populations and normal adults. How endogenous cholinergic action affects neuronal activity in higher cortical areas is unknown. Here we tested the effects of electrical stimulation of the cortical source of acetylcholine in primates, the Nucleus Basalis of Meynert, on neural activity while monkeys performed working memory tasks. Stimulation delivered in an intermittent fashion improved behavioral performance and increased neuronal activity during the delay period of the task but not to the phasic responses of visual stimuli. Selectivity of neuronal responses broadened, rendering the bump of activity in an attractor network more stable, and filtering distracting stimuli more effectively. These neural results show that acetylcholine has effects on neural activity and selectivity in the prefrontal cortex opposing those of dopamine and fine tuning aggregate neural ensemble activity based on neuromodulatory tone.