Cortical auditory evoked responses of older adults with and without probable mild cognitive impairment

Abstract

Objective: Hearing loss has been well-documented as a risk factor for cognitive impairment, but the simple presence of hearing loss is not a sufficient predictor of cognitive decline. Although auditory behavioral research has not revealed an effective indicator of early cognitive impairment, a limited number of studies using cortical auditory evoked potentials (CAEPs) have shown promising evidence of an auditory neurophysiological indicator of early-stage cognitive impairment. The purpose of this study was to examine the P1-N1-P2 complex for indicators of cognitive impairment.

Methods: The latency and amplitude of the P1-N1-P2 complex was measured for two stimuli (pure tone, speech) in two groups: cognitively normal older adults (CNOAs) and older adults with probable mild cognitive impairment (MCI), based on the Montreal Cognitive Assessment.

Results: Significantly smaller P2 amplitudes were found for those with probable MCI compared to CNOA across stimulus conditions. Stimulus effects were found for P1 and P2 latency.

Conclusion: P2 amplitude may be a useful indicator of early-stage cognitive impairment.

Significance: As effective treatments become available, early identification of cognitive impairment can facilitate the prescription of treatment at the earliest juncture. CAEPs have the potential to serve as efficient, non-invasive, cost-effective indicators of future cognitive decline and impairment.

Keywords: Aging; Cognition; Cortical auditory evoked potentials; Hearing; Mild cognitive impairment; P1–N1–P2 complex.