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Many older adults have difficulty understanding speech in the presence of background sound. Experiences resulting from such comprehension difficulties include increased listening effort and fatigue, and reduced enjoyment. Social interactions may become less appealing in the context of such experiences, and age-related hearing loss is associated with an increased risk of social isolation and associated negative psychosocial health outcomes. However, the precise relationship between age-related hearing loss and social isolation is not well described. Here, we review the literature on the relationship between hearing loss and social isolation, and propose a framework with different stages along a continuous progression: within-situation disengagement from listening, social withdrawal, and social isolation. We describe the distinct characteristics of each stage and suggest potential interventions to mitigate negative impacts of hearing loss on social lives and health. We close by outlining potential implications for researchers and clinicians.

Fluctuating background sounds facilitate speech intelligibility by providing speech ‘glimpses’ (masking release). Older adults benefit less from glimpses, but masking release is typically investigated using isolated sentences. Recent work indicates that using engaging, continuous speech materials (e.g., spoken stories) may qualitatively alter speech-in-noise listening. Moreover, neural sensitivity to different amplitude envelope profiles (ramped, damped) changes with age, but whether this affects speech listening is unknown. In three online experiments, we investigate how masking release in younger and older adults differs for masked sentences and stories, and how speech intelligibility varies with masker amplitude profile. Intelligibility was generally greater for damped than ramped maskers. Masking release was reduced in older relative to younger adults for disconnected sentences, and stories with a randomized sentence order. Critically, when listening to stories with an engaging and coherent narrative, older adults demonstrated equal or greater masking release compared to younger adults. Older adults thus appear to benefit from ‘glimpses’ as much as, or more than, younger adults when the speech they are listening to follows a coherent topical thread. Our results highlight the importance of cognitive and motivational factors for speech understanding, and suggest that previous work may have underestimated speech-listening abilities in older adults.

Speech is more intelligible when it is spoken by familiar than unfamiliar people. Two cues to voice identity are glottal pulse rate (GPR) and vocal tract length (VTL): perhaps these features are more accurately represented for familiar voices in a listener’s brain. If so, listeners should be able to discriminate smaller manipulations to perceptual correlates of these vocal parameters for familiar than unfamiliar voices. We recruited pairs of friends who had known each other for 0.5–22.5 years. We measured thresholds for discriminating pitch (correlate of GPR) and formant spacing (correlate of VTL; ‘VTL-timbre’) for voices that were familiar (friends) and unfamiliar (friends of other participants). When a competing talker was present, speech was substantially more intelligible when it was spoken in a familiar voice. Discrimination thresholds were not systematically smaller for familiar compared to unfamiliar talkers. Although, participants detected smaller deviations to VTL-timbre than pitch uniquely for familiar talkers, suggesting a different balance of characteristics contribute to discrimination of familiar and unfamiliar voices. Across participants, we found no relationship between the size of the intelligibility benefit for a familiar over an unfamiliar voice and the difference in discrimination thresholds for the same voices. Also, the intelligibility benefit was not affected by the acoustic manipulations we imposed on voices to assess discrimination thresholds. Overall, these results provide no evidence that two important cues to voice identity—pitch and VTL-timbre—are more accurately represented when voices are familiar, or are necessarily responsible for the large intelligibility benefit derived from familiar voices.

Comprehension of speech masked by background sound requires increased cognitive processing, which makes listening effortful. Research in hearing has focused on such challenging listening experiences, in part because they are thought to contribute to social withdrawal in people with hearing impairment. Research has focused less on positive listening experiences, such as enjoyment and absorption/engagement, despite their potential importance in motivating effortful listening. Moreover, the artificial speech materials – such as disconnected, brief sentences – commonly utilized to investigate speech intelligibility and listening effort may be ill-suited to capture positive experiences when listening is challenging. Here, we investigate how listening to naturalistic spoken stories under acoustic challenges influences the quality of listening experiences. We show (1) that story absorption and enjoyment are only minimally affected by moderate speech masking although listening effort increases; (2) that familiarity with the Harry Potter books and/or movies, providing thematic knowledge, increases absorption and enjoyment and reduces listening effort when listening to the audio of a Harry-Potter summary presented in multi-talker babble; and (3) that absorption and enjoyment increase and effort decreases over time as individuals listen to several stories successively in multi-talker babble. Our research indicates that naturalistic, spoken stories can reveal several concurrent listening experiences and that familiarity with a narrative can increase engagement and reduce effort. Our work also demonstrates that, although listening effort may increase with speech degradation, listeners may still find the experience both absorbing and enjoyable.

Previous experience with a voice can help listeners understand speech when a competing talker is present. Using the coordinate-response measure task (Bolia, Nelson, Ericson, & Simpson, 2000), Johnsrude et al. (2013) demonstrated that speech is more intelligible when either the target or competing (masking) talker is a long-term spouse than when both talkers are unfamiliar (termed familiar-target and familiar-masker benefits, respectively). To better understand how familiarity improves intelligibility, we measured the familiar-target and familiar-masker benefits in older and younger spouses using a more challenging matrix task, and compared the benefits listeners gain from spouses' and friends' voices. On each trial, participants heard two sentences from the Boston University Gerald (Kidd, Best, & Mason, 2008) corpus (" ") and reported words from the sentence beginning with a target name word. A familiar-masker benefit was not observed, but all groups showed a robust familiar-target benefit and its magnitude did not differ between spouses and friends. The familiar-target benefit was not influenced by relationship length (in the range of 1.5-52 years). Together, these results imply that the familiar-target benefit can develop from various types of relationships and has already reached a plateau around 1.5 years after meeting a new friend. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Understanding speech in adverse conditions is affected by experience—a familiar voice is substantially more intelligible than an unfamiliar voice when competing speech is present, even if the content of the speech (the words) are controlled. This familiar-voice benefit is observed consistently, but its underpinnings are unclear: Do familiar voices simply attract more attention, are they inherently more intelligible because they have predictable acoustic characteristics, or are they more intelligible in a mixture because they are more resistant to interference from other sounds? We recruited pairs of native English participants who were friends or romantic couples. Participants reported words from closed-set English sentences (Oldenburg matrix test; HörTech, 2014) spoken by a familiar talker (the participant’s partner) or an unfamiliar talker. We compared three masker conditions that are acoustically similar but differ in their demands: (1) English Oldenburg sentences; (2) Oldenburg sentences in a language incomprehensible to the listener (Russian or Spanish); and (3) unintelligible signal-correlated noise. We adaptively varied the target-to-masker ratio to obtain 50% speech reception thresholds. We observed a large (~5 dB) familiar-voice benefit when the target and masker were both English sentences. This benefit was attenuated (to ~2 dB) when the masker was in an incomprehensible language and disappeared when it was signal-correlated noise. These results suggest that familiar voices did not benefit intelligibility because they were more predictable or because they attracted greater attention; rather, familiarity with a target voice reduced interference from maskers that are linguistically similar to the target.

A novel method is presented for creating a probability map from histologically defined cytoarchitectonic data, customised for the anatomy of individual fMRI volunteers. Postmortem structural and cytoarchitectonic information from a published dataset is combined with high resolution structural MR images using deformable registration of a region of interest. In this paper, we have targeted the three sub-areas of the primary auditory cortex (located on Heschl's gyrus); however, the method could be applied to any other cytoarchitectonic region. The resulting probability maps show a significantly higher overlap than previously generated maps using the same cytoarchitectonic data, and more accurately span the macroanatomical structure of the auditory cortex. This improvement indicates a high potential for spatially accurate fMRI analysis, allowing more reliable correlation between anatomical structure and function. We validate the approach using fMRI data from nine individuals, taken from a published dataset. We compare activation for stimuli evoking a pitch percept to activation for acoustically matched noise, and demonstrate that the primary auditory cortex (Te1.0) and the lateral region Te1.2 are sensitive to pitch, whereas Te1.1 is not.

Twenty-two patients who had undergone unilateral anterior resection of either the left (LT) or right (RT) temporal lobe and 13 normal control (NC) subjects were tested on a lexical-decision task and a story-memory task. Stimuli were presented aurally, and, in the latter task, at five different speech rates ranging from 125 words per minute (wpm) to 325 wpm. Memory for stories in the LT group was not abnormally sensitive to the effect of increasing rate, although it was inferior to that of the NC group at all speeds. This argues against the hypothesis that the verbal memory deficit evident after LT resection is partially attributable to an abnormally slow processing of verbal information. But LT subjects were impaired at judging the lexicality of words and nonwords presented aurally, suggesting that the left anterior temporal region plays a special role in the processing of speech sounds.

The everyday act of speaking involves the complex processes of speech motor control. One important feature of such control is regulation of articulation when auditory concomitants of speech do not correspond to the intended motor gesture. While theoretical accounts of speech monitoring posit multiple functional components required for detection of errors in speech planning (e.g., Levelt, 1983), neuroimaging studies generally indicate either single brain regions sensitive to speech production errors, or small, discrete networks. Here we demonstrate that the complex system controlling speech is supported by a complex neural network that is involved in linguistic, motoric and sensory processing. With the aid of novel real-time acoustic analyses and representational similarity analyses of fMRI signals, our data show functionally differentiated networks underlying auditory feedback control of speech.