Musicality - Tuned to the melody of vocal emotions

Musicians outperform non-musicians in vocal emotion perception, likely because of increased sensitivity to acoustic cues, such as fundamental frequency (F0) and timbre. Yet, how musicians make use of these acoustic cues to perceive emotions, and how they might differ from non-musicians, is unclear. To address these points, we created vocal stimuli that conveyed happiness, fear, pleasure or sadness, either in all acoustic cues, or selectively in either F0 or timbre only. We then compared vocal emotion perception performance between professional/semi-professional musicians (N = 39) and non-musicians (N = 38), all socialized in Western music culture. Compared to non-musicians, musicians classified vocal emotions more accurately. This advantage was seen in the full and F0-modulated conditions, but was absent in the timbre-modulated condition indicating that musicians excel at perceiving the melody (F0), but not the timbre of vocal emotions. Further, F0 seemed more important than timbre for the recognition of all emotional categories. Additional exploratory analyses revealed a link between time-varying F0 perception in music and voices that was independent of musical training. Together, these findings suggest that musicians are particularly tuned to the melody of vocal emotions, presumably due to a natural predisposition to exploit melodic patterns.

Electrophysiological Correlates of Vocal Emotional Processing in Musicians and Non-Musicians

Musicians outperform non-musicians in vocal emotion recognition, but the underlying mechanisms are still debated. Behavioral measures highlight the importance of auditory sensitivity towards emotional voice cues. However, it remains unclear whether and how this group difference is reflected at the brain level. Here, we compared event-related potentials (ERPs) to acoustically manipulated voices between musicians (n = 39) and non-musicians (n = 39). We used parameter-specific voice morphing to create and present vocal stimuli that conveyed happiness, fear, pleasure, or sadness, either in all acoustic cues or selectively in either pitch contour (F0) or timbre. Although the fronto-central P200 (150-250 ms) and N400 (300-500 ms) components were modulated by pitch and timbre, differences between musicians and non-musicians appeared only for a centro-parietal late positive potential (500-1000 ms). Thus, this study does not support an early auditory specialization in musicians but suggests instead that musicality affects the manner in which listeners use acoustic voice cues during later, controlled aspects of emotion evaluation.

Contributions of fundamental frequency and timbre to vocal emotion perception and their electrophysiological correlates

Our ability to infer a speaker's emotional state depends on the processing of acoustic parameters such as fundamental frequency (F0) and timbre. Yet, how these parameters are processed and integrated to inform emotion perception remains largely unknown. Here we pursued this issue using a novel parameter-specific voice morphing technique to create stimuli with emotion modulations in only F0 or only timbre. We used these stimuli together with fully modulated vocal stimuli in an event-related potential (ERP) study in which participants listened to and identified stimulus emotion. ERPs (P200 and N400) and behavioral data converged in showing that both F0 and timbre support emotion processing but do so differently for different emotions: Whereas F0 was most relevant for responses to happy, fearful and sad voices, timbre was most relevant for responses to voices expressing pleasure. Together, these findings offer original insights into the relative significance of different acoustic parameters for early neuronal representations of speaker emotion and show that such representations are predictive of subsequent evaluative judgments.

Music training and empathy positively impact adults' sensitivity to infant distress

Crying is the most powerful auditory signal of infant need. Adults' ability to perceive and respond to crying is important for infant survival and in the provision of care. This study investigated a number of listener variables that might impact on adults' perception of infant cry distress, namely parental status, musical training, and empathy. Sensitivity to infant distress was tested using a previously validated task, which experimentally manipulated distress by varying the pitch of infant cries. This task required that participants discriminate between pitch differences and interpret these as differences in infant distress. Parents with musical training showed a significant advantage on this task when compared with parents without. The extent of the advantage was correlated with the amount of self-reported musical training. For non-parents, individual differences in empathy were associated with task performance, with higher empathy scores corresponding to greater sensitivity to infant distress. We suggest that sensitivity to infant distress can be impacted by a number of listener variables, and may be amenable to training.

An ERP study of vocal emotion processing in asymmetric Parkinson's disease

Parkinson's disease (PD) has been related to impaired processing of emotional speech intonation (emotional prosody). One distinctive feature of idiopathic PD is motor symptom asymmetry, with striatal dysfunction being strongest in the hemisphere contralateral to the most affected body side. It is still unclear whether this asymmetry may affect vocal emotion perception. Here, we tested 22 PD patients (10 with predominantly left-sided [LPD] and 12 with predominantly right-sided motor symptoms) and 22 healthy controls in an event-related potential study. Sentences conveying different emotional intonations were presented in lexical and pseudo-speech versions. Task varied between an explicit and an implicit instruction. Of specific interest was emotional salience detection from prosody, reflected in the P200 component. We predicted that patients with predominantly right-striatal dysfunction (LPD) would exhibit P200 alterations. Our results support this assumption. LPD patients showed enhanced P200 amplitudes, and specific deficits were observed for disgust prosody, explicit anger processing and implicit processing of happy prosody. Lexical speech was predominantly affected while the processing of pseudo-speech was largely intact. P200 amplitude in patients correlated significantly with left motor scores and asymmetry indices. The data suggest that emotional salience detection from prosody is affected by asymmetric neuronal degeneration in PD.