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Abstract Localizing sounds in noisy environments can be challenging. Here, we reproduce real-life soundscapes to investigate the effects of environmental noise on sound localization experience. We evaluated participants' performance and metacognitive assessments, including measures of sound localization effort and confidence, while also tracking their spontaneous head movements. Normal-hearing participants (N = 30) were engaged in a speech-localization task conducted in three common soundscapes that progressively increased in complexity: nature, traffic, and a cocktail party setting. To control visual information and measure behaviors, we used visual virtual reality technology. The results revealed that the complexity of the soundscape had an impact on both performance errors and metacognitive evaluations. Participants reported increased effort and reduced confidence for sound localization in more complex noise environments. On the contrary, the level of soundscape complexity did not influence the use of spontaneous exploratory head-related behaviors. We also observed that, irrespective of the noisy condition, participants who implemented a higher number of head rotations and explored a wider extent of space by rotating their heads made lower localization errors. Interestingly, we found preliminary evidence that an increase in spontaneous head movements, specifically the extent of head rotation, leads to a decrease in perceived effort and an increase in confidence at the single-trial level. These findings expand previous observations regarding sound localization in noisy environments by broadening the perspective to also include metacognitive evaluations, exploratory behaviors and their interactions.

Moving the head while a sound is playing improves its localization in human listeners, in children and adults, with or without hearing problems. It remains to be ascertained if this benefit can also extend to aging adults with hearing-loss, a population in which spatial hearing difficulties are often documented and intervention solutions are scant. Here we examined performance of elderly adults (61–82 years old) with symmetrical or asymmetrical age-related hearing-loss, while they localized sounds with their head fixed or free to move. Using motion-tracking in combination with free-field sound delivery in visual virtual reality, we tested participants in two auditory spatial tasks: front-back discrimination and 3D sound localization in front space. Front-back discrimination was easier for participants with symmetrical compared to asymmetrical hearing-loss, yet both groups reduced their front-back errors when head-movements were allowed. In 3D sound localization, free head-movements reduced errors in the horizontal dimension and in a composite measure that computed errors in 3D space. Errors in 3D space improved for participants with asymmetrical hearing-impairment when the head was free to move. These preliminary findings extend to aging adults with hearing-loss the literature on the advantage of head-movements on sound localization, and suggest that the disparity of auditory cues at the two ears can modulate this benefit. These results point to the possibility of taking advantage of self-regulation strategies and active behavior when promoting spatial hearing skills.

Interactions with talkers wearing face masks have become part of our daily routine since the beginning of the COVID-19 pandemic. Using an on-line experiment resembling a video conference, we examined the impact of face masks on speech comprehension. Typical-hearing listeners performed a speech-in-noise task while seeing talkers with visible lips, talkers wearing a surgical mask, or just the name of the talker displayed on screen. The target voice was masked by concurrent distracting talkers. We measured performance, confidence and listening effort scores, as well as meta-cognitive monitoring (the ability to adapt self-judgments to actual performance). Hiding the talkers behind a screen or concealing their lips via a face mask led to lower performance, lower confidence scores, and increased perceived effort. Moreover, meta-cognitive monitoring was worse when listening in these conditions compared with listening to an unmasked talker. These findings have implications on everyday communication for typical-hearing individuals and for hearing-impaired populations.