ROLE OF ACETYLCHOLINE IN THE ACTIVITY OF SENSORI-MOTOR AND SUPPRESSOR AREAS OF THE CORTEX

Abstract

Topical application of acetylcholine, eserine, and cholinesterase prepd. from the pancreas of dogs exerts the following effects on the cortex of the brain in cats and monkeys: 1.) Eserine with acetylcholine stimulates suppressor areas as indicated by temporary suppression or diminution of cortical electrical activity and by temporary elimination of the responsiveness of the motor cortex to electrical stimulation as recorded by electromyograms. These substances also increase the responsiveness of the cortex to afferent stimuli as indicated by electrocorticograms. 2) Cholinesterase diminishes cortical activity and the responsiveness to afferent stimuli. It is inferred from these observations and the data reported in the literature that acetylcholine is linked with the process of excitation in motor, sensory and suppressor neurons on the cortex, but no attempt has been made to determine whether or not in the reactions studied synaptic transmission is essentially altered.