P300 in individuals with auditory neuropathy spectrum disorder

Abstract

Introduction: Typically, individuals with auditory neuropathy spectrum disorder (ANSD) show the presence of otoacoustic emissions and elevated/absent auditory brainstem responses. It has been reported that individuals with ANSD, in spite of absent or abnormal ABRs, show auditory cortical potentials. P300 is an endogenous cortical-evoked potential and reflects the changes in the cortical activity when the attention is paid toward the sound. This can effectively quantify the complex cortical sensory-cognitive processing underlying active auditory perception. Therefore, the present study was taken up to investigate the cortical representation of active auditory discrimination skills in individuals with ANSD using P300 response. Methods: Twenty-five individuals with ANSD and 25 individuals with normal hearing sensitivity were the participants. The individuals with ANSD had audiometric thresholds ranging from normal hearing to moderate hearing loss. P300 was recorded using/ba/-/da/stimulus contrast in the oddball paradigm. The latency and the amplitude of P300 response were marked and analyzed using repeated measures ANOVA. Sensitivity and reaction time in identifying the oddball were also measured. Results: The result showed poor sensitivity and longer reaction time in individuals with ANSD compared to individuals with normal hearing. P300 responses were prolonged in latency and reduced in amplitude in individuals with ANSD. Both the latency and amplitude of P300 response were related to perceptual measures. Conclusion: P300 response was present in individuals with ANSD but with prolonged latency and reduced amplitude.