Alcohol Effects on the P2 component of Auditory Evoked Potentials

Abstract

This is a second part of a research aimed to study the effects of alcohol on the electrophysiological processes in student volunteers. The first part showed that alcohol slowed the Omitted Stimulus Potential (OSP). This work studied the ethanol effects on the parameters (i.e. rate of rise, amplitude and peak latency) of the P2 component of the evoked potentials (EPs) yielded by trains of auditory stimuli. It is hypothesized here that if P2 and OSP waves share some common neural processes then alcohol should also affect these specific parameters. A dose of 0.8 g/kg of alcohol or a placebo (0 g/kg) was administered to two groups of 15 young men who were tested before and again after treatment. The pre-post treatment change in each of the measurements was used to assess the treatment effects. The results showed that compared to placebo, alcohol slowed the P2 rise rate and reduced its amplitude, with no effects on peak latency. The rise rate is more sensitive to alcohol but more resistant to the adaptation process. Alcohol resembles the response inhibition model acting against the adaptation. The rise rate of the P2 and the OSP waves are affected by alcohol in a similar fashion, suggesting similar neural generative mechanisms.

The Relationship between Parameters of Long-Latency Evoked Potentials in a Multisensory Design

“…For each stimulus modality, separate linear regressions were used to test the relationship between parameters of the LLEP. 17 These regressions were calculated using the grand-average data for each parameter.…”

Omitted Stimulus Potential depends on the sensory modality

“…Two waves can also differ in amplitude and peak latency while having the same rise rate or differ in their rate of rise and amplitude but have the same latency (see Fig. 6 in Hernández et al 2014). Hernández and Vogel-Sprott (2010b) showed that acute alcohol can slow the OSP rise rate and latency but not its amplitude.…”

“…Hernández and Vogel-Sprott (2010b) showed that acute alcohol can slow the OSP rise rate and latency but not its amplitude. Later, Hernández et al (2014), who worked on the cognitive P200 wave, showed that the rate of rise resulted in more sensitivity to alcohol and more resistance to the habituation process compared to the latency and amplitude. The rate of rise was the only parameter modified by alcohol in the same fashion in both P200 and OSP.…”

“…We believe that if some common processes are involved in the generation of these measures, the OSP rise rate for auditory stimuli should be faster for visual or somatosensory stimuli. The rise rate parameter, although less studied than the latency and amplitude measures, can provide additional information because it informs the speed of recruitment of activated nerve fibres at the cortical level (Hernández et al 2014).…”

Cortical auditory evoked potentials – clinical applications and usability in central auditory processes evaluation

“…[66,67]). Za pomocą CAEP próbuje się obiektywnie oceniać funkcjonowanie różnego rodzaju procesów poznawczych w chorobach związanych z nieprawidłowym działaniem ośrodkowego układu nerwowego, takich jak chociażby: epilepsja [68], udar mózgu [69], śpiączka [70], zespół alkoholowy [71], depresja, schizofrenia [66], choroba Alzheimera [72] czy chociażby różnego rodzaju formy demencji [73]. Naturalnym polem klinicznego wykorzystania słuchowych potencjałów korowych pozostaje jednak od lat przede wszystkim audiologia.…”