Role of Active Listening and Listening Effort on Contralateral Suppression of Transient Evoked Otoacousic Emissions

Abstract

Background and ObjectivesThe present study aimed to investigate the effect of active listening and listening effort on the contralateral suppression of transient evoked otoacoustic emissions (CSTEOAEs).Subjects and MethodsTwenty eight young adults participated in the study. Transient evoked otoacoustic emissions (TEOAEs) were recorded using ‘linear’ clicks at 60 dB peSPL, in three contralateral noise conditions. In condition 1, TEOAEs were obtained in the presence of white noise in the contralateral ear. While, in condition 2, speech was embedded into white noise at +3, −3, and −9 dB signal-to-noise ratio (SNR) and delivered to the contralateral ear. The SNR was varied to investigate the effect of listening effort on the CSTEOAE. In condition 3, speech was played backwards and embedded into white noise at −3 dB SNR. The conditions 1 and 3 served as passive listening condition and the condition 2 served as active listening condition. In active listening condition, the participants categorized the words in to two groups (e.g., animal and vehicle).ResultsCSTEOAE was found to be largest in the presence of white noise, and the amount of CSTEOAE was not significantly different between active and passive listening conditions (condition 2 and 3). Listening effort had an effect on the CSTEOAE, the amount of suppression increased with listening effort, when SNR was decreased from +3 dB to −3 dB. However, when the SNR was further reduced to −9 dB, there was no further increase in the amount of CSTEOAE, instead there was a reduction in the amount of suppression.ConclusionsThe findings of the present study show that listening effort might affect CSTEOAE.

Short Term Test-Retest Reliability of Contralateral Inhibition of Distortion Product Otoacoustic Emissions

“…Medial olivocochlear bundles (MOCBs) are efferent pathways in the auditory system which controls functioning of outer hair cells in the cochlea. MOCBs are shown to have a positive effect on various auditory functions in humans, such as speech recognition in noise [ 6 ], selective attention [ 7 ] and active listening [ 8 ]. In addition, studies have also reported that medial olivocochlear (MOC) reflex predicts the success achieved from auditory perceptual training [ 9 ] and can be used to measure the success obtained with auditory perceptual training [ 10 ].…”

“…Acoustic stimulation to the contralateral ear, termed as contralateral inhibition of OAE has been widely used to measure the functioning of the efferent pathways among humans. Many of the researchers have measured MOCB activity using contralateral inhibition of click evoked or transient evoked otoacoustic emissions (TEOAEs) [ 6 - 8 , 10 ] and contralateral acoustic stimulation (CAS) has shown to reduce the amplitude of transient evoked otoacoustic emissions for various types of noise [ 11 ]. The effects of CAS on the DPOAE has been reported by several investigators [ 5 , 12 - 15 ] and findings of these investigations have reported both reduction and enhancement of amplitude of DPOAEs [ 12 , 13 , 16 , 17 ].…”

Otoacoustic emission suppression in children diagnosed with central auditory processing disorder and speech in noise perception deficits

“…Although the MOC function time course shows heterogeneity and is not yet elaborately described in humans [41], it may be hypothesized that the unmasking effect of MOC efferent pathways leading to better speech recognition in babble performance requires a gradual and steady increase across a millisecond range. It should be noted that there is a documented [42,43] gradual increase in adults with normal hearing sensitivity as measured for a smaller overall time window (4-18ms) than the one that was used in the present study. For the left ear, the normal SinB group presented small suppression levels with one of the largest suppression levels seen at 4-14 msec, whereas large suppression levels exceeding 2 dB were observed for the abnormal SinB group.…”

Perceptual gating of a brainstem reflex facilitates speech understanding in human listeners

“…Bottom-up mechanisms such as the increased reflexive activation of the MOCR by wideband stimuli with flat power spectra (Lilaonitkul and Guinan, 2009) may explain a facet of our results—especially during passive listening. For instance, reduced MOCR activation observed for babble noise during passive listening may arise from it being a weaker suppressor than ‘stationary’ noises such as white noise or speech-shaped noise (Boothalingam et al, 2014; Kalaiah et al, 2017b). However, vocoded stimuli with fewer channels should have also activated the MOCR more effectively due to their more ‘noise-like’ spectra.…”