Cortical auditory potentials and cognitive potentials in individuals with and without vestibular dysfunction

Abstract

Background: Vestibular dysfunction is known to affect cognitive abilities related to the processing of spatial and non-spatial information. P300 is an event-related potential (ERP) used to assess cognitive function. Studies have shown abnormalities in P300 in individuals with vestibular hypofunction.  However, the literature shows equivocal findings for P300 in individuals with vestibular dysfunction. The aim of present study was to compare the latency and amplitude of cortical auditory evoked potential and P300 between individuals with vestibular dysfunction and individuals with no vestibular dysfunction. Methods: Forty adults with a mean age of 40.5 years participated in the study. Group I included 20 adults diagnosed with vestibular dysfunction and group II included 20 age-matched adults with no vestibular dysfunction. The P300 was recorded using pure-tones in an odd-ball paradigm, from electrode sites Cz and Pz. The latency and amplitude of peaks P1, N1, P2, N2 P300, and N4 were measured. Results:  The results showed no significant difference in the latency and amplitude of peaks P1, N1, P2, and N2 of the cortical auditory potentials between groups. The P300 was absent in approximately 30% of individuals with vestibular dysfunction meanwhile, it was present in all individuals in group II. The mean latency and amplitude of the P300 and latency of N4 were not significantly different between the groups. However, a significant difference was observed in N4 amplitude between groups at both electrode sites. And, no correlation was observed between the DHI score and the P300 parameters in group I. Conclusions: the P300 was absent in a greater number of individuals with vestibular dysfunction, suggesting cognitive impairment. However, when the P300 was present the peak latency and amplitude showed no significant difference in both groups.