Intra- and Interindividual Correlations Between Auditory Evoked Potentials and Speech Perception in Cochlear Implant Users

Abstract

Several electrophysiological techniques have been used to supplement behavioural measurements in the evaluation of the benefit of cochlear implantation, namely the electrically evoked auditory brainstem response (EABR), electrically evoked middle latency response (EMLR) and electrically evoked late latency response (EALR). To study the interdependence of these responses, the present paper deals with a combination of EABR, EMLR and EALR measurements obtained from 15 postlingually deaf subjects implanted with the Nucleus multichannel device at the University Hospital Nijmegen. In particular, we investigated whether there were intercorrelations between amplitude and latencies of the evoked potential peaks and/or correlations with long-term speech perception scores. Significant correlations were found between the peak V amplitude of the EABR and the NaPa and NbPb amplitudes of the EMLR. No significant correlation was found between the EABR and EMLR amplitudes on the one hand and EALR peak amplitudes on the other. In addition, no significant correlations were found between any of the EABR or EMLR peak amplitudes and speech perception test results. A moderate but significant relation was found between the EALR peak amplitude and speech perception test results. Unlike latencies of earlier peaks, the latency of the EALR peak P2 was significantly related to the speech perception scores.

Towards a Closed-Loop Cochlear Implant System: Application of Embedded Monitoring of Peripheral and Central Neural Activity

“…The MLR likely represents the first cortical response that can be recorded using scalp electrodes. Although the MLR varies with stimulus intensity, the relationship with speech perception performance has been poor [36], [37]. In subjects with poor speech perception, larger degrees of ELMR variability have been found [38].…”

Activity-Dependent Developmental Plasticity of the Auditory Brain Stem in Children Who Use Cochlear Implants

“…Given the results of the present study, it is unlikely that poorer speech perception outcomes are due to limitations in evoked brain stem activity. Indeed the activity evoked by electrical stimulation in the auditory brain stem measured by EABR has not been predictive of psychophysical outcomes with a cochlear implant (Abbas & Brown, 1991;Makhdoum, Groenen, Snik, & van den Broek, 1998). Similarly, larger numbers of surviving spiral ganglion in humans does not predict better behavioural outcomes with an implant (Nadol et al, 2001).…”

Neurophysiology of Cochlear Implant Users II: Comparison Among Speech Perception, Dynamic Range, and Physiological Measures

“…Reports of late auditory potentials evoked with electrical stimulation have included recordings of the N1, P2, P300, and mismatch negativity (MMN) response elicited with pulsed tones (Oviatt & Kileny, 1991), stimulated electrode pairs (Makhdoum, Groenen, Snik, & van den Broek, 1997;Ponton & Don, 1995), and speech (Kaga, Kodera, Hirota, & Tsuzuka, 1991;Kraus et al, 1993;Micco et al, 1995). Results suggest that cortical responses provide a mechanism for understanding how electrical stimuli are registered by the central auditory system.…”