Cortical acetylcholine release during operant behaviour in rabbits

Acetylcholine released from the visual and sensorimotor cortices was collected in awake rabbits while they were responding for water reinforcement under one of four behavioural paradigms. Acetylcholine release from both sites was found to increase over baseline levels in all behavioural conditions. This was interpreted as due to the diffuse cholinergic input to the cortex from the reticular formation. However, in one condition a significantly greater increase was observed from sensorimotor cortex alone. This supports the existence of a second, more specific cholinergic component in the cortex.