Auditory Evoked Potentials under Active and Passive Hearing Conditions in Adult Cochlear Implant Users

Abstract

ObjectivesSpeech perception abilities, which vary widely among cochlear implant (CI) users, are considered to be associated with the integrity of the central auditory pathways from the auditory nerve to the cortex. Therefore, auditory evoked potentials (AEPs) are used to evaluate central auditory processing, which is thought to contribute to speech perception in CI subjects. In AEPs, the P300 component reflects the cognitive ability of subjects to detect and respond to stimuli and has most frequently been used and investigated in CI subjects. Other studies have used mismatched negativity (MMN) to examine central auditory processing. It is important to compare MMN and P300 and examine the auditory processing mechanisms involved in these components. Our study therefore aimed to investigate the relationship between P300 and MMN using both active and passive hearing paradigms in CI and normal hearing (NH) subjects.MethodsOur subjects consisted of 3 CI subjects and 3 NH subjects. An oddball paradigm was used to deliver the stimuli on both components. The frequent stimuli were 1,000-Hz tone bursts, whereas the rare stimuli were 1,500, 2,000, and 4,000-Hz.ResultsAs the frequency contrasts increased, the P3 latencies increased in the CI subjects. However, the latency in NH subjects did not change significantly across the frequency contrast conditions. MMNs were identified for both the CI and NH subjects; the latencies in the CI subjects were longer than those in the NH subjects. However, there were no differences in the latencies of either the CI or NH subjects in the 3 frequency contrast tasks.ConclusionOur results indicated that different auditory processing pathways are involved in the active and passive hearing conditions based on the P300 and MMN data and that a combination of both responses plays an important role in the comprehension of auditory processing mechanisms in CI subjects.

Event-related potentials for better speech perception in noise by cochlear implant users

“…(For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.) contrast with different places of articulation (Groenen et al, 2001;Henkin et al, 2009), likely showing similar results to the studies using a difficult tone contrast (Roman et al, 2005;Obuchi et al, 2012), but not those using an easy contrast (Zhang et al, 2011).…”

The Impact of Age and Duration of Cochlear Implant in a Congenital Deaf Population: An ERP Study

“…Generally, implanted post verbal adult patients showed longer latencies compared to hearing patients with the same age [12]- [15].…”

Mismatch negativity in children with cochlear implant

“…9 Furthermore, Hahne et al and Obuchi et al also reported delayed latencies and smaller amplitudes in CI patients than in normal hearing controls. 10,11 This finding may be related to difficulties faced by CI subjects in using temporal and spectral cues. They appeared to require longer time to process the incoming information as compared to the normal hearing subjects.…”