MISMATCH NEGATIVITY AND P300 TO BEHAVIORALLY PERCEPTIBLE AND IMPERCEPTIBLE TEMPORAL CONTRASTS¹

Abstract

The purpose of this study was to specify whether electrophysiological indices of behavioral discrimination of auditory duration could be demonstrated. Mismatch negativities and P300s were recorded to perceptible and imperceptible stimuli in 23 normal-hearing young adults. Behaviorally perceptible and imperceptible stimuli were demonstrated by measuring difference limens in a standard psychophysical procedure in a subset of participants (n = 8). Perceptibility was further demonstrated using a standard clinical pattern-perception test and modified-duration pattern tests created for this study. Mismatch negativities and P300s were recorded with an oddball paradigm using stimuli identical to those used in behavioral testing. All participants exhibited P300s in the perceptible contrast, while responses were absent for the imperceptible contrast. Mismatch negativities were found for 18 and 5 of 23 participants to the perceptible and imperceptible contrasts, respectively. The mismatch negativity did not correspond with behavioral discrimination and, as such, one could question its clinical feasibility. The P300 more accurately reflected behavioral discrimination performance in the current paradigm.

Mismatch Negativity and P300 to Behaviorally Perceptible and Imperceptible Frequency and Intensity Contrasts

“…The findings in the amplitude and spectral domains were similar to those reported previously in the temporal domain by White, et al (2010). Collectively, these data and the previous findings (White, et al, 2010) challenge the notion that the mismatch negativity can be used as an electrophysiological correlate for behavioral discrimination of perceptible auditory contrasts. Although the P300 better reflected behavioral discrimination, its clinical utility is limited because it requires the listener to actively participate in the task.…”

“…the electrophysiological paradigm used was identical to that used previously (White, et al, 2010), except the different tonal stimuli were inserted into the stimulus sequences. Prior to electrophysiological testing, behavioral testing was conducted to verify the perceptibility of stimuli.…”

“…Presence of the MMN and P300 responses required agreement of three judges (i.e., the two authors and a research assistant) who were blind to test condition. For a more detailed discussion of the procedures for determining response presence, the reader is referred to the earlier publication by White, et al (2010).…”

“…In a recent publication, White, Stuart, and Najem (2010) evaluated the clinical utility of the P300 and the mismatch negativity as electrophysiological correlates of auditory behavioral discrimination in the temporal domain. Behaviorally perceptible and imperceptible stimulus duration contrasts were implemented.…”

“…to provide optimal intervention, it is best to identify the underlying areas of deficit. The study by White, et al (2010) was based on auditory discrimination in the temporal domain. In the current report, we summarize the results of data collected under the same paradigm utilizing amplitude/intensity and spectral/frequency stimulus contrasts, during the auditory discrimination task.…”