Children's Acoustic and Linguistic Adaptations to Peers With Hearing Impairment

Healthy Communication Partners Modify Their Speech When Conversing With Individuals With Parkinson's Disease

Purpose For individuals with Parkinson's disease (PD), conversational interactions can be challenging. Efforts to improve the success of these interactions have largely fallen on the individual with PD. Successful communication, however, involves contributions from both the individual with PD and their communication partner. The current study examines whether healthy communication partners naturally engage in different acoustic-prosodic behavior (speech compensations) when conversing with an individual with PD and, further, whether such behavior aids communication success. Method Measures of articulatory precision, speaking rate, and pitch variability were extracted from the speech of healthy speakers engaged in goal-directed dialogue with other healthy speakers (healthy-healthy dyads) and with individuals with PD (healthy-PD dyads). Speech compensations, operationally defined as significant differences in healthy speakers' acoustic-prosodic behavior in healthy-healthy dyads versus healthy-PD dyads, were calculated for the three speech behaviors. Finally, the relationships between speech behaviors and an objective measure of communicative efficiency were examined. Results Healthy speakers engaged in speech characterized by greater articulatory precision and slower speaking rate when conversing with individuals with PD relative to conversations with other healthy individuals. However, these adaptive speech compensations were not predictive of communicative efficiency. Conclusions Evidence that healthy speakers naturally engage in speech compensations when conversing with individuals with PD is novel, yet consistent with findings from studies with other populations in which conversation can be challenging. In the case of PD, these compensatory behaviors did not support communication outcomes. While preliminary in nature, the results raise important questions regarding the speech behavior of healthy communication partners and provide directions for future work.

Non-verbal Adaptation to the Interlocutors' Inner Characteristics: Relevance, Challenges, and Future Directions

Human diversity cannot be denied. In our everyday social interactions, we constantly experience the fact that each individual is a unique combination of characteristics with specific cultural norms, roles, personality, and mood. Efficient social interaction thus requires an adaptation of communication behaviors to each specific interlocutor that one encounters. This is especially true for non-verbal communication that is more unconscious and automatic than verbal communication. Consequently, non-verbal communication needs to be understood as a dynamic and adaptive process in the theoretical modeling and study of social interactions. This perspective paper presents relevance, challenges, and future directions for the study of non-verbal adaptation in social interactions. It proposes that non-verbal adaptability is more pertinently studied as adaptation to interlocutor's inner characteristics (i.e., expectations or preferences) than to interlocutor's behaviors per se, because behaviors are communication messages that individuals interpret in order to understand their interlocutors. The affiliation and control dimensions of the Interpersonal Circumplex Model are proposed as a framework to measure both the interlocutors' inner characteristics (self-reported) and the individuals' non-verbal responses (external coders). These measures can then be compared across different interactions to assess an actual change in behavior tailored to different interlocutors. These recommendations are proposed in the hope of generating more research on the topic of non-verbal adaptability. Indeed, after having gathered the evidence on average effects of non-verbal behaviors, the field can go further than a “one size fits all” approach, by investigating the predictors, moderators, and outcomes of non-verbal adaptation to the interlocutors' inner characteristics.

The Clear-Speech Benefit for School-Age Children: Speech-in-Noise and Speech-in-Speech Recognition

Purpose Talkers often modify their speech when communicating with individuals who struggle to understand speech, such as listeners with hearing loss. This study evaluated the benefit of clear speech in school-age children and adults with normal hearing for speech-in-noise and speech-in-speech recognition. Method Masked sentence recognition thresholds were estimated for school-age children and adults using an adaptive procedure. In Experiment 1, the target and masker were summed and presented over a loudspeaker located directly in front of the listener. The masker was either speech-shaped noise or two-talker speech, and target sentences were produced using a clear or conversational speaking style. In Experiment 2, stimuli were presented over headphones. The two-talker speech masker was diotic (M₀). Clear and conversational target sentences were presented either in-phase (T₀) or out-of-phase (T_π) between the two ears. The M₀T_π condition introduces a segregation cue that was expected to improve performance. Results For speech presented over a single loudspeaker (Experiment 1), the clear-speech benefit was independent of age for the noise masker, but it increased with age for the two-talker masker. Similar age effects for the two-talker speech masker were seen under headphones with diotic presentation (M₀T₀), but comparable clear-speech benefit as a function of age was observed with a binaural cue to facilitate segregation (M₀T_π). Conclusions Consistent with prior research, children showed a robust clear-speech benefit for speech-in-noise recognition. Immaturity in the ability to segregate target from masker speech may limit young children's ability to benefit from clear-speech modifications for speech-in-speech recognition under some conditions. When provided with a cue that facilitates segregation, children as young as 4-7 years of age derived a clear-speech benefit in a two-talker masker that was similar to the benefit experienced by adults.

Conversational Coordination of Articulation Responds to Context: A Clinical Test Case With Traumatic Brain Injury

Purpose Coordination of communicative behavior supports shared understanding in conversation. The current study brings together analysis of two speech coordination strategies, entrainment and compensation of articulation, in a preliminary investigation into whether strategy organization is shaped by a challenging communicative context-conversing with a person who has a communication disorder. Method As an initial clinical test case, an automated measure of articulatory precision was analyzed in a corpus of spoken dialogue, where a confederate conversed with participants with traumatic brain injury (n = 28) and participants with no brain injury (n = 48). Results Overall, the confederate engaged in significant entrainment and high compensation (hyperarticulation) in conversations with participants with traumatic brain injury relative to significant entrainment and low compensation (hypoarticulation) in conversations with participants with no brain injury. Furthermore, the confederate's articulatory precision changed over the course of the conversations. Conclusions Findings suggest that the organization of conversational coordination is sensitive to context, supporting synergistic models of spoken dialogue. While corpus limitations are acknowledged, these initial results point to differences in the way in which speech strategies are realized in challenging communicative contexts, highlighting a viable and important target for investigation with clinical populations. A framework for investigating speech coordination strategies in tandem and ideas for advancing this line of inquiry serve as key contributions of this work.

How do aging and age-related hearing loss affect the ability to communicate effectively in challenging communicative conditions?

This study investigated the relation between the intelligibility of conversational and clear speech produced by older and younger adults and (a) the acoustic profile of their speech (b) communication effectiveness. Speech samples from 30 talkers from the elderLUCID corpus were used: 10 young adults (YA), 10 older adults with normal hearing (OANH) and 10 older adults with presbycusis (OAHL). Samples were extracted from recordings made while participants completed a problem-solving cooperative task (diapix) with a conversational partner who could either hear them easily (NORM) or via a simulated hearing loss (HLS), which led talkers to naturally adopt a clear speaking style. In speech-in-noise listening experiments involving 21 young adult listeners, speech samples by OANH and OAHL were rated and perceived as less intelligible than those of YA talkers. HLS samples were more intelligible than NORM samples, with greater improvements in intelligibility across conditions seen for OA speech. The presence of presbycusis affected (a) the clear speech strategies adopted by OAHL talkers and (b) task effectiveness: OAHL talkers showed some adaptations consistent with an increase in vocal effort, and it took them significantly longer than the YA group to complete the diapix task. The relative energy in the 1-3 kHz frequency region of the long-term average spectrum was the feature that best predicted: (a) the intelligibility of speech samples, and (b) task transaction time in the HLS condition. Overall, our study suggests that spontaneous speech produced by older adults is less intelligible in babble noise, probably due to less energy present in the 1-3 kHz frequency range rich in acoustic cues. Even mild presbycusis in 'healthy aged' adults can affect the dynamic adaptations in speech that are beneficial for effective communication.