Auditory and Cognitive Effects of Aging on Perception of Environmental Sounds in Natural Auditory Scenes

Abstract

Purpose When environmental sounds are semantically incongruent with the background scene (e.g., horse galloping in a restaurant) they can be identified more accurately by young normal hearing listeners (YNH) than sounds congruent with the scene (e.g., horse galloping at a racetrack). This study investigated how age and high frequency audibility affect this Incongruency Advantage (IA) effect. Methods In Experiments 1a and 1b, elderly listeners (N=18 for 1a, N=10 for 1b) with age-appropriate hearing (EAH) were tested on target sounds and auditory scenes in five Sound-to-Scene ratios (So/Sc) between −3 to −18 dB. Experiment 2 tested eleven YNH on the same sound/scene pairings lowpass-filtered at 4 kHz (YNH-4k). Results The EAH and YNH-4k groups exhibited an almost identical pattern of significant IAs, but both were at approximately 3.9 dB higher So/Sc than the previously tested YNH. However, the psychometric functions revealed a shallower slope for EAH compared to YNH for the Congruent stimuli only, suggesting a greater difficulty for the elderly in attending to sounds expected to occur in a scene. Conclusions These findings indicate that semantic relationship between environmental sounds in soundscapes are mediated by both audibility and cognitive factors and suggest a method for dissociating the two.

Toward a Nonspeech Test of Auditory Cognition: Semantic Context Effects in Environmental Sound Identification in Adults of Varying Age and Hearing Abilities

“…Moderate-to-high correlations between FEST-S and BKB-SIN scores for both coherent and incoherent sound sequences obtained in Experiment 2 with CI users may be further indicative of shared perceptual processes involved in the perception of auditory scenes and speech in noise. This finding is consistent with previous reports of the involvement of working memory in speech perception by older and hearing-impaired adults [38], and extends the previous results to the perception of environmental sounds in auditory scenes. On the other hand, unlike findings from speech perception research [5], the results do not indicate that older or hearing-impaired listeners rely on contextual information to a greater degree than YNH adults.…”

“…Furthermore, the present results were obtained when all stimuli were presented in quiet. The addition of background noise, even without any identifiable semantic content, could also affect the strength of the context effect—a possibility consistent with prior research [13, 38]. …”

“…Identification of specific sounds, and of their temporal position in the sequence, is improved when surrounding sounds form a semantic memory network, which can be activated by any of the member sounds [33, 37]. On the other hand, other work has shown that this effect may be level-dependent and that semantic context can also facilitate sound segregation when a specific sound is semantically incongruent with the rest of the auditory scene [13, 15, 38]. It appears that depending on task requirements (i.e., what the individual subject is listening for) semantic context can aid in either highlighting the sounds that do not go together or facilitating identification and memory encoding of the sounds that do go together.…”

“…For instance, the sound of rooster crowing in an auditory scene of a hospital emergency room is more detectable than the same sound heard in a barnyard ambience. This effect, however, is level-dependent, and tends to reverse with a low sound-to-scene energy ratio [16, 38]. …”

Environmental Sound Perception: Effects of Aging and Hearing Loss

“…Generally, identification of isolated everyday familiar sounds presented in quiet appears to be well preserved in healthy older adults with normal hearing or mild hearing losses (Ballas and Barnes 1988;Harris et al 2017;Shafiro et al 2020). Differences in environmental sound perception between older and younger listeners become more pronounced when stimulus quality is degraded due to reverberation, signal processing distortions, or masking by extraneous sounds (Dick et al 2016;Gygi and Shafiro 2013). Similarly, performance of older listeners is also more negatively affected than that of young adults when task complexity is increased, resulting in a greater cognitive load and leading to more effortful listening (e.g., attending to several sounds or performing more than one task).…”