Recent investigations of convulsive therapy have emphasized EEG delta activity as the neurophysiologic basis for the induced behavioral change.1-5 Little study, however, has been given to the biochemical effects of this therapy, except in the course of investigations of head injuries.
In investigations of head trauma significance has been ascribed to changes in the acetylcholine-cholinesterase systems both for the behavioral and for the electroencephalographic effects. An increase in free acetylcholine6 and an alteration of the ratio of cholinesterases7 in the spinal fluid have been positively correlated with the degree of EEG abnormality and degree of neurologic deficit. The EEG patterns were "blocked," and some improvement in clinical status was reported following the administration of atropine.7,8 In convulsive therapy, atropine and scopolamine were observed to block the appearance of delta activity,9 although the systemic effects of the large doses of these agents were marked.
FINK M. Effect of Anticholinergic Agent, Diethazine, on EEG and BehaviorSignificance for Theory of Convulsive Therapy. AMA Arch NeurPsych. 1958;80(3):380-387. doi:10.1001/archneurpsyc.1958.02340090116017