Accession Number : ADA130280

Title :   Effects of Impact Acceleration on Somatosensory Evoked Potentials.

Descriptive Note : Research rept.,


Personal Author(s) : Berger,Michael D ; Weiss,Marc S

PDF Url : ADA130280

Report Date : Apr 1983

Pagination or Media Count : 65

Abstract : In order to test and evaluate impact protection devices, an impact-injury model for restrained humans in a crash environment must be developed. Disruption of the functioning of the central nervous system (CNS) is an important consequence of impact injury involving the head and neck, and is an important consideration in the development of a useful impact-injury model. Ultimately, neurophysiological criteria for functional injury of the CNS are desired. The main purpose of the experiments reported here is to identify some of the measures of CNS function which may provide the basis for establishing such criteria. In these experiments, eight unanesthatized Rhesus monkeys, with torsos restrained in a seated position, and with head and neck free to move, were subjected to peak sled accelerations in the -X direction ranging from 42 m/s sq. second to 963 sq. second. The rsults of these analyses indicate that neurophysiological indices of injury may include: increases in latencies of the cervical Somatosensory evoked potentials (SEP) peaks exceeding 2.5%; large changes in the amplitude of the cervical SEP; changes in ripples on the cortical primary SEP; and substantial and persistent changes in the surface-positive cortical primary SEP. In particular, analysis of shifts in latency of the cervical SEP suggests the possibility of an injury threshold in the vicinity of 700 - 800 sq. second. Smaller shifts in latency occuring near 600 sq. second may indicate a pre-injury condition.

Descriptors :   *Impact acceleration, *Wounds and injuries, *Central nervous system, *Neurophysiology, Protective equipment, Anatomical models, Rhesus monkeys, Head(Anatomy), Neck(Anatomy), Crash injuries, Test methods, Sleds, Electroencephalography, Cerebral cortex, Exponential functions, Regression analysis, Quantitative analysis, Reaction time, Heart rate, Temperature, Curve fitting, Mathematical models, Cross correlation

Subject Categories : Medicine and Medical Research
      Stress Physiology

Distribution Statement : APPROVED FOR PUBLIC RELEASE