Neurophysiological Bases of Event-Related Potentials

摘要

In order to more fully understand the physiological and psychological significance of event-related brain potentials (ERPs), cortical and subcortical recordings were obtained from monkeys performing an operant conditioning task (cued reaction time). Five groups of monkeys each were studied over a period of five years to examine several important issues--distribution of ERPs in the brain, neurochemical mediators of ERPs, homology of ERPs across species, relationship of ERPs to associative conditioning, and the effects of varying signal and non-signal proportionalities. ERPs in some monkeys increased in amplitude when the warning stimulus was made a rare event. It seems clear that a complex intracerebral system mediates the generation of scalp-recorded ERPs. Chemical (MPTP) inhibition or destruction of the pars compact a region of substantia nigra in three monkeys produced Parkinsonism and a lengthening of movement time with less effect on initiation time, and decreased the amplitudes of ERPs in the nigral region and the N2 component of premotor cortex. Behavior was disrupted by cholinergic antagonism whether or not the drug crossed the blood-brain barrier, suggesting caution in the interpretation of the effects of systemically administered drugs on ERPs.