Interaural time difference based spatial release from masking with asymmetric hearing over a video conference app

Due to the difficulty of conducting offline laboratory experiments during the coronavirus outbreak, remote experiments such as experiments over video conference apps have become an important method to collect data for hearing researchers. For remote testing using headphone presentations, compared to monaural (i.e., unilateral or diotic) audio stimuli, dichotic stimuli (i.e., sounds with differences between left and right ears) are used in relatively less studies. In this study, a binaural hearing task of spatial release from masking (SRM) was tested in laboratory and over a video conference app, i.e., Tencent Meeting. In the experiment, the effects of interaural time difference (ITD) on SRM were compared between symmetric and asymmetric hearing which were realized by using a fixed interaural level difference (ILD) of 0 dB and −15 dB respectively. Results showed that 1) SRM was observed in the remote test but it was >4 dB smaller than the laboratory test; 2) asymmetric hearing would lead to a ~2 dB significant decrease in the amount of masking release in both laboratory and remote conditions. The results indicate that binaural hearing could be measured remotely using the stereo sharing mode of video conference apps, but the effects of binaural cues especially ITDs may be degraded to some extent.