For dynamic sounds, such as vocal expressions, duration often varies alongside speed. Compared to longer sounds, shorter sounds unfold more quickly. Here, we asked whether listeners implicitly use this confound when representing temporal regularities in their environment. In addition, we explored the role of emotions in this process. Using a mismatch negativity (MMN) paradigm, we asked participants to watch a silent movie while passively listening to a stream of task-irrelevant sounds. In Experiment 1, one surprised and one neutral vocalization were compressed and stretched to create stimuli of 378 and 600 ms duration. Stimuli were presented in four blocks, two of which used surprised and two of which used neutral expressions. In one surprised and one neutral block, short and long stimuli served as standards and deviants, respectively. In the other two blocks, the assignment of standards and deviants was reversed. We observed a climbing MMN-like negativity shortly after deviant onset, which suggests that listeners implicitly track sound speed and detect speed changes. Additionally, this MMN-like effect emerged earlier and was larger for long than short deviants, suggesting greater sensitivity to duration increments or slowing down than to decrements or speeding up. Last, deviance detection was facilitated in surprised relative to neutral blocks, indicating that emotion enhances temporal processing. Experiment 2 was comparable to Experiment 1 with the exception that sounds were spectrally rotated to remove vocal emotional content. This abolished the emotional processing benefit, but preserved the other effects. Together, these results provide insights into listener sensitivity to sound speed and raise the possibility that speed biases duration judgements implicitly in a feed-forward manner. Moreover, this bias may be amplified for duration increments relative to decrements and within an emotional relative to a neutral stimulus context.

This study examined how trustworthiness impressions depend on vocal expressive and person characteristics and how their dependence may be explained by acoustical profiles. Sentences spoken in a range of emotional and conversational expressions by 20 speakers differing in age and sex were presented to 80 age and sex matched listeners who rated speaker trustworthiness. Positive speaker valence but not arousal consistently predicted greater perceived trustworthiness. Additionally, voices from younger as compared with older and female as compared with male speakers were judged more trustworthy. Acoustic analysis highlighted several parameters as relevant for differentiating trustworthiness ratings and showed that effects largely overlapped with those for speaker valence and age, but not sex. Specifically, a fast speech rate, a low harmonic-to-noise ratio, and a low fundamental frequency mean and standard deviation differentiated trustworthy from untrustworthy, positive from negative, and younger from older voices. Male and female voices differed in other ways. Together, these results show that a speaker’s expressive as well as person characteristics shape trustworthiness impressions and that their effect likely results from a combination of low-level perceptual and higher-order conceptual processes.

This study examined how trustworthiness impressions depend on vocal expressive and person characteristics and how their dependence may be explained by acoustical profiles. Sentences spoken in a range of emotional and conversational expressions by 20 speakers differing in age and sex were presented to 80 age and sex matched listeners who rated speaker trustworthiness. Positive speaker valence but not arousal consistently predicted greater perceived trustworthiness. Additionally, voices from younger as compared with older and female as compared with male speakers were judged more trustworthy. Acoustic analysis highlighted several parameters as relevant for being perceived as trustworthy (i.e., accelerated tempo, low harmonic-to-noise ratio, more shimmer, low fundamental frequency, more jitter, large intensity range) and showed that effects partially overlapped with those for perceived speaker affect, age, but not sex. Specifically, a fast speech rate and a lower harmonic-to-noise ratio differentiated trustworthy from untrustworthy, positive from negative, and younger from older voices. Male and female voices differed in other ways. Together, these results show that a speaker's expressive as well as person characteristics shape trustworthiness impressions and that their effect likely results from a combination of lowlevel perceptual and higher-order conceptual processes.

Deception detection can be of great value during the juristic investigation. Although the neural signatures of deception have been widely documented, most prior studies were biased by difficulty levels. That is, deceptive behavior typically required more effort, making deception detection possibly effort detection. Furthermore, no study has examined the generalizability across instructed and spontaneous responses and across participants. To explore these issues, we used a dual-task paradigm, where the difficulty level was balanced between truth-telling and lying, and the instructed and spontaneous truth-telling and lying were collected independently. Using Multivoxel pattern analysis, we were able to decode truth-telling versus lying with a balanced difficulty level. Results showed that the angular gyrus (AG), inferior frontal gyrus (IFG), and postcentral gyrus could differentiate lying from truth-telling. Critically, linear classifiers trained to distinguish instructed truthful and deceptive responses could correctly differentiate spontaneous truthful and deceptive responses in AG and IFG with above-chance accuracy. In addition, with a leave-one-participant-out analysis, multivoxel neural patterns from AG could classify if the left-out participant was lying or not in a trial. These results indicate the commonality of neural responses subserved instructed and spontaneous deceptive behavior as well as the feasibility of cross-participant deception validation.

After this article [1] was published, the authors notified the journal that the voice frequency and intensity analyses forming part of the reported study were done incorrectly in that they did not exclude pauses or unvoiced elements. The authors also subsequently noted small errors in the computation of the F0 trace due to inconsistent voicing (e.g., fry). To address these issues, they revised the acoustic analyses, and also repeated all of the statistical analyses with adjusted modelling approaches. This showed that the results and conclusions reported in the original article were not consistently supported or replicated. Specifically, the results and conclusions depending on voice acoustics were substantially affected by the analysis errors, whereas results and conclusions as regards to speaker affect, age and sex changed minimally. A member of PLOS ONE's Editorial Board reviewed the reanalyses and advised that the main conclusions of the article are no longer supported. Given the extent to which the analysis issues impact the results and conclusions of the article, the authors retract this article. The authors plan to publish an updated version of the article that reports the corrected analyses, results, and conclusions.