Long Latency Auditory Evoked Responses in the Identification of Children With Central Auditory Processing Disorders: A Scoping Review

Abstract

Purpose: The long latency auditory evoked responses (LLAERs), originating in the auditory cortex, are often considered a biomarker for maturity in the central auditory system and may therefore be useful in the evaluation of children with central auditory processing disorder (CAPD). However, the characteristics of the LLAERs elicited in this population have not been widely described, and clinical applications remain unclear. The goal of this scoping review was to investigate if LLAERs can be used to identify children with CAPD. Method: A systematic search strategy was used to identify studies that analyzed the latencies and amplitudes of P1, N1, P2, and N2 waveforms of the LLAERs. The online databases, including Embase, Web of Science, MEDLINE, PubMed, ProQuest, and CINAHL, as well as the gray literature were searched for papers published in English and French between January 1980 and May 2021. Results: Seventeen papers met the eligibility criteria and were included in the study. Four papers had pre- and posttraining study designs, and the remaining studies were cross-sectional. Several studies reported significant differences in LLAERs between children with CAPD and their normal-hearing peers, and the results tended toward longer latencies and smaller amplitudes regardless of LLAER waves considered. N1 and/or N2 results were most likely to reveal significant differences between children with CAPD and normal-hearing controls and could potentially be considered a biomarker for CAPD. Conclusions: It seems that LLAER assessments, especially waves N1 and N2, might assist in better identification of CAPD children. However, considering heterogeneity in the methodology among the included studies, the results should be interpreted with caution. Well-designed studies on children with confirmed CAPD using standard diagnostic and assessment protocols are suggested.