Pupil Dilation Reflects Perceptual Priorities During a Receptive Speech Task.

OBJECTIVES: The listening demand incurred by speech perception fluctuates in normal conversation. At the acoustic-phonetic level, natural variation in pronunciation acts as speedbumps to accurate lexical selection. Any given utterance may be more or less phonetically ambiguous-a problem that must be resolved by the listener to choose the correct word. This becomes especially apparent when considering two common speech registers-clear and casual-that have characteristically different levels of phonetic ambiguity. Clear speech prioritizes intelligibility through hyperarticulation which results in less ambiguity at the phonetic level, while casual speech tends to have a more collapsed acoustic space. We hypothesized that listeners would invest greater cognitive resources while listening to casual speech to resolve the increased amount of phonetic ambiguity, as compared with clear speech. To this end, we used pupillometry as an online measure of listening effort during perception of clear and casual continuous speech in two background conditions: quiet and noise. DESIGN: Forty-eight participants performed a probe detection task while listening to spoken, nonsensical sentences (masked and unmasked) while recording pupil size. Pupil size was modeled using growth curve analysis to capture the dynamics of the pupil response as the sentence unfolded. RESULTS: Pupil size during listening was sensitive to the presence of noise and speech register (clear/casual). Unsurprisingly, listeners had overall larger pupil dilations during speech perception in noise, replicating earlier work. The pupil dilation pattern for clear and casual sentences was considerably more complex. Pupil dilation during clear speech trials was slightly larger than for casual speech, across quiet and noisy backgrounds. CONCLUSIONS: We suggest that listener motivation could explain the larger pupil dilations to clearly spoken speech. We propose that, bounded by the context of this task, listeners devoted more resources to perceiving the speech signal with the greatest acoustic/phonetic fidelity. Further, we unexpectedly found systematic differences in pupil dilation preceding the onset of the spoken sentences. Together, these data demonstrate that the pupillary system is not merely reactive but also adaptive-sensitive to both task structure and listener motivation to maximize accurate perception in a limited resource system.

The reward positivity shows increased amplitude and decreased latency with increasing age in early childhood.

The reward positivity (RewP) is a widely studied measure of neural response to rewards, yet little is known about normative developmental characteristics of the RewP during early childhood. The present study utilized a pooled community sample of 309 4- to 6-year-old children who participated in the Doors guessing game to examine the latency and amplitude of the RewP. Peak detection of the gain-loss difference waveform was conducted for electrodes Fz, Cz, Pz, Oz and the mean activity in a 100 ms window centered around this peak was analyzed. There was a significant decrease in RewP latency (RewP was earlier) and increase in RewP amplitude (RewP magnitude was larger) with advancing age in this cross-sectional analysis. Further, these were independent effects, as both RewP latency and RewP amplitude were uniquely associated with children's age. Moreover, our results indicate that the RewP latency in 4- to 6-year-olds falls outside the 250-350 ms window typically used to quantify the RewP (RewP latency in our sample = 381 ms; SD = 60.15). The internal consistency for latency (.64) and amplitude (.27) of the RewP were characterized by moderate to low reliability, consistent with previous work on the reliability of difference scores. Overall, results demonstrate RewP differences in both timing and amplitude across age in early childhood, and suggest that both amplitude and latency of the RewP might function as individual difference measures of reward processing. These findings are discussed in the context of methodological considerations and the development of reward processing across early childhood.

Using TMS to evaluate a causal role for right posterior temporal cortex in talker-specific phonetic processing.

Theories suggest that speech perception is informed by listeners' beliefs of what phonetic variation is typical of a talker. A previous fMRI study found right middle temporal gyrus (RMTG) sensitivity to whether a phonetic variant was typical of a talker, consistent with literature suggesting that the right hemisphere may play a key role in conditioning phonetic identity on talker information. The current work used transcranial magnetic stimulation (TMS) to test whether the RMTG plays a causal role in processing talker-specific phonetic variation. Listeners were exposed to talkers who differed in how they produced voiceless stop consonants while TMS was applied to RMTG, left MTG, or scalp vertex. Listeners subsequently showed near-ceiling performance in indicating which of two variants was typical of a trained talker, regardless of previous stimulation site. Thus, even though the RMTG is recruited for talker-specific phonetic processing, modulation of its function may have only modest consequences.

Young children with suicidal thoughts and behaviors more likely to resolve conflicts with violence, homicide, or suicide: A study of internal working models using narratives.

There is mounting evidence that young children who express suicidal ideation (SI) have a different conceptualization of death than their peers. This study characterizes 3- to 6-year-olds' depictions of violence, death, and suicidal themes in a story completion task as a function of their history of SI. Participants were 228 children with depression (3.0-6.9 years) who completed a comprehensive psychiatric assessment and four story stem narratives. For each narrative, an interviewer began a story with a conflict that the child was encouraged to resolve. Children's resolutions were coded for standard themes and negative atypical themes including violence and homicide, accidental harm or death, and suicidal ideation/acts. Themes were examined as a function of children's SI status: active-SI (n = 25), passive-SI (n = 28), or no history of SI (n = 175). Across the narratives, 89 children described at least one negative atypical theme: violence or homicide (n = 78), accidental harm or death (n = 22), and suicide (n = 13). The responses of children with active-SI included significantly more violence or homicide than children without SI. Moreover, current active-SI predicted suicidal themes. There were no group differences in accidental harm or death, nor in common aggressive or punitive acts (e.g., hitting, yelling, spanking), indicating specificity between active-SI and more intense violence and death-related themes. In sum, young children with active SI are more likely than their depressed peers without SI to incorporate violence, homicide, and suicide into their narratives around conflict resolution. These themes appear more salient to depressed children with SI and pervasive in their thoughts and problem-solving strategies. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Nonliteral language processing across the lifespan.

Studies investigating the effects of aging on nonliteral language processing have mainly focused on one sensory modality, for example written vignettes. In the current study, we used a video-based task to examine the effect of healthy aging on social communication perception using a novel database called RISC (Relation Inference in Social Communication). By means of an online recruitment platform, we asked young, middle-aged, and older adults between the ages of 18 and 76 (N = 100) to evaluate videos of actors using different forms of literal and nonliteral language, such as sarcasm or teasing. The participants' task was to infer the speakers' belief and the speakers' intention. Older participants demonstrated lower accuracy in discriminating nonliteral from literal interactions compared to younger and middle-aged groups. When evaluating speaker intentions, older adults judged sarcasm as friendlier compared to literal negative utterances. We also found that the older the participant, the more difficulty they have identifying teasing as insincere. Our results expand on age-related similarities and differences in evaluating speaker intentions and demonstrate the practicality of the RISC database for studying nonliteral language across the lifespan.