The Event-related Potential "P3"

Abstract:

The growth of the older population in America brings with it a new set of problems. One such problem is the loss of hearing sensitivity and speech perception. For many, the ability to hear decreases with advancing age. For a percentage of those adults, this decreased ability to hear involves a greater reduction in understanding speech than would be expected based solely on the amount of hearing loss. This reduction has has been termed the "central auditory aging affect." Assessment of central auditory impairment involves the administration of specific tests designed to evaluate the integrity of the central auditory nervous system. One such test used clinically is the Synthetic Sentence Identification test. Another test, an event-related potential test known as the P3 component, has been suggested as a potential central auditory test. It was the purpose of this study to investigate the use of the P3 as a measure of central auditory function. Thirty-one healthy and cognitively intact male veterans received a battery of behavioral audiometric testing and P3 testing. The subjects were classified as either centrally impaired (CI) or peripherally impaired (PI) based on the results of the behavioral tests. The data from the P3 testing, according to group classification, were submitted for statistical analysis. Within the limits imposed by the design of the study, the following conclusions were drawn: (a) The latency of the component invoked in a quiet condition supported the placement of the groups. The PI group latency was consistent with previously reported age-related norms. The CI group latency, however, was longer than the PI groups indicating an increased processing time or extended stimulus evaluation time. (b) The introduction of a medium band noise served to increase the complexity of the stimulus or introduced noise into the system as evidenced by increased latencies for both groups. (c) While both groups demonstrated an effect of the noise, the PI group appeared to be more affected by the noise than the CI group. (d) The results of this investigation suggest that an internal noise already existed in the CI group so the addition of the external noise had minimal effect on their speech processing time; whereas the addition of the external noise for the PI group caused a significant delay in processing speed. Clinically, the results suggest that speech processing in some older adults with hearing loss maybe more compromised than in others due to the presence of more neural noise in the system which decreases their speech processing time, and hence their ability to understand speech.

Dissertation Discovery Company and University of Florida are dedicated to making scholarly works more discoverable and accessible throughout the world. This dissertation, "The Event-related Potential "P3"" by Sharon Ann Sandridge, was obtained from University of Florida and is being sold with permission from the author. A digital copy of thi...