Neurophysiological Evaluation of Right-Ear Advantage During Dichotic Listening

Abstract

Right-ear advantage refers to the observation that when two different speech stimuli are simultaneously presented to both ears, listeners report stimuli more correctly from the right ear than the left. It is assumed to result from prominent projection along the auditory pathways to the contralateral hemisphere and the dominance of the left auditory cortex for the perception of speech elements. Our study aimed to investigate the role of attention in the right-ear advantage. We recorded magnetoencephalography data while participants listened to pairs of Japanese two-syllable words (namely, “/ta/ /ko/” or “/i/ /ka/”). The amplitudes of the stimuli were modulated at 35 Hz in one ear and 45 Hz in the other. Such frequency-tagging allowed the selective quantification of left and right auditory cortex responses to left and right ear stimuli. Behavioral tests confirmed the right-ear advantage, with higher accuracy for stimuli presented to the right ear than to the left. The amplitude of the auditory steady-state response was larger when attending to the stimuli compared to passive listening. We detected a correlation between the attention-related increase in the amplitude of the auditory steady-state response and the laterality index of behavioral accuracy. The right-ear advantage in the free-response dichotic listening was also found in neural activities in the left auditory cortex, suggesting that it was related to the allocation of attention to both ears.

Dichotic listening and interhemispheric integration after callosotomy: a systematic review

“…This reversed association between the directions of ear preference and lateralisation has been replicated consistently using various dichotic paradigms (e.g., Fernandes & Smith, 2000;Geffen & Caudrey, 1981;Hugdahl, Carlsson, Uvebrant, & Lundervold, 1997;Strauss, Gaddes, & Wada, 1987;Zatorre, 1989). Studies on healthy individuals using non-invasive functional imaging techniques confirm this general pattern on individual and group-level (e.g., Hund-Georgiadis, Lex, Friederici, & Von Cramon, 2002;Tanaka et al, 2021;Van der Haegen, Westerhausen, Hugdahl, & Brysbaert, 2013;Westerhausen, Kompus, & Hugdahl, 2014).…”

The Laterality of Age-Related Hearing Loss and Depression

“…Additional future studies could include whether or not frankly asymmetric HL (e.g., single-sided deafness in the left versus right ear) is more strongly associated with depression and other neuropsychiatric conditions of older life. Moreover, there is a well-established ''right-ear advantage'' for speech recognition; when two distinct speech stimuli are presented to both ears simultaneously, studies have shown that listeners report stimuli more correctly from the right ear compared to the left ear (56)(57)(58)(59). Further investigation of the relative contributions of speech recognition in each ear (rather than hearing thresholds) may also elucidate any potential contributions of auditory laterality to the known association between HL and depression.…”

Subliminal Training Techniques for Cognitive, Emotional and Behavioural Balance. The role of Emerging Technologies

“…Research has already shown that the left hemisphere controls the leading right eye, whereas the left controls the right hemisphere, which is responsible for various nonconscious processes as well as for negative feelings (Goodarzi et al, 2015;Kostandov & Arzumanov, 1986). Research also indicates that when two different speech stimuli are simultaneously presented to both ears, listeners report stimuli more correctly from the right ear than the left, indicating separate observations of left and right-ear responses to acoustic stimuli (Tanaka et al, 2021).…”