James G. Wepsic

Alteration of nociception by stimulation of cerebellar structures in the monkey

Abstract Fifteen cerebellar targets were stimulated to evaluate the effect of cerebellar stimulation upon painful tail shocks in monkeys. An elevation of nociceptive thresholds occurred when cerebellar areas whose efferents traverse the brachium conjunctivum were stimulated. Stimulation of cerebellar areas related to the brachium restiformis produced no change.

The Neurophysiological Effects of Amphetamine Upon the Cat Amygdala

Changes in the brain catecholamines (CA), norepinephrine (NE), dopamine (DA) and serotonin, are related to changes in affective behavior. Fluctuation in the synthesis, storage and turnover of these molecules has been demonstrated in different behavioral states and, conversely, different behavioral states have been produced by administering drugs which modify the uptake, metabolism, or degradation of such amines. It is thought that behavioral changes depend upon neural activity and anatomical areas important to affective states were grouped by Paul MacLean into the Limbic System. Understanding the role of CA in the limbic system is crucial to the understanding of the neurochemical basis for affective behavior. To this end, we are studying the influence of amphetamine upon electrophysiological relationships between the amygdala, septal nucleus, and hypothalamic ventromedial nucleus (HVM). The anatomical localization of NE, its effects on behavior thought to be referable to the amygdala, and the neuro-pharmacologic relationship between amphetamine and NE will first be discussed.

Technique for Radiofrequency Gasserian Ganglionectomy

Indications, technical procedures, and complications are discussed for the performance of thermal electrocoagulation of the trigeminal preganglionic rootlets and gasserian ganglion. Specific steps in preoperative evaluation, premedication, anesthetic management, and technical performance of graded lesion-making utilizing radiographic control, physiologic stimulation and intraoperative patient monitoring are discussed. A survey of complications is presented.