Accession Number : AD0765406

Title :   Somatosensory Stimulus Modification of Background Alpha Activity,

Corporate Author : ARMY MEDICAL RESEARCH LAB FORT KNOX KY

Personal Author(s) : O'Mara,Peter A.

Report Date : 17 JAN 1973

Pagination or Media Count : 26

Abstract : The effects of median nerve stimulation upon the centrally recorded human alpha rhythm were investigated. A comparison of the differences between 180 degrees out of phase alpha rhythm averages obtained under non-stimulus and stimulus conditions revealed the presence of evoked potential (EP)-EEG interactions as early as 30 msec following stimulation. Alpha activity was extensively modified 200 msec following stimulus presentation. The magnitude of the stimulus modifications of the background alpha rhythm was observed to decrease markedly within and between successive data collection trials. Systematic reductions in the amplitude of the somatosensory EP were also observed. The presence of systematic increases in background EEG amplitude and corresponding decreases in EP amplitude may adversely affect the detection of EP components and limit the interpretation of variance data collected during EP averaging. (Author)

Descriptors :   (*ELECTROENCEPHALOGRAPHY, *SENSES(PHYSIOLOGY)), BRAIN, STIMULATION(PHYSIOLOGY), RESPONSE(BIOLOGY), PERCEPTION, TOUCH

Subject Categories : Anatomy and Physiology

Distribution Statement : APPROVED FOR PUBLIC RELEASE