Cortical haemodynamic responses predict individual ability to recognise vocal emotions with uninformative pitch cues but do not distinguish different emotions

Neural response to vocal emotional intensity in youth

Previous research has identified regions of the brain that are sensitive to emotional intensity in faces, with some evidence for developmental differences in this pattern of response. However, comparable understanding of how the brain tracks linear variations in emotional prosody is limited-especially in youth samples. The current study used novel stimuli (morphing emotional prosody from neutral to anger/happiness in linear increments) to investigate whether neural response to vocal emotion was parametrically modulated by emotional intensity and whether there were age-related changes in this effect. Participants aged 8-21 years (n = 56, 52% female) completed a vocal emotion recognition task, in which they identified the intended emotion in morphed recordings of vocal prosody, while undergoing functional magnetic resonance imaging. Parametric analyses of whole-brain response to morphed stimuli found that activation in the bilateral superior temporal gyrus (STG) scaled to emotional intensity in angry (but not happy) voices. Multivariate region-of-interest analyses revealed the same pattern in the right amygdala. Sensitivity to emotional intensity did not vary by participants' age. These findings provide evidence for the linear parameterization of emotional intensity in angry vocal prosody within the bilateral STG and right amygdala. Although findings should be replicated, the current results also suggest that this pattern of neural sensitivity may not be subject to strong developmental influences.

Awareness of embodiment enhances enjoyment and engages sensorimotor cortices

Whether in performing arts, sporting, or everyday contexts, when we watch others move, we tend to enjoy bodies moving in synchrony. Our enjoyment of body movements is further enhanced by our own prior experience with performing those movements, or our 'embodied experience'. The relationships between movement synchrony and enjoyment, as well as embodied experience and movement enjoyment, are well known. The interaction between enjoyment of movements, synchrony, and embodiment is less well understood, and may be central for developing new approaches for enriching social interaction. To examine the interplay between movement enjoyment, synchrony, and embodiment, we asked participants to copy another person's movements as accurately as possible, thereby gaining embodied experience of movement sequences. Participants then viewed other dyads performing the same or different sequences synchronously, and we assessed participants' recognition of having performed these sequences, as well as their enjoyment of each movement sequence. We used functional near-infrared spectroscopy to measure cortical activation over frontotemporal sensorimotor regions while participants performed and viewed movements. We found that enjoyment was greatest when participants had mirrored the sequence and recognised it, suggesting that awareness of embodiment may be central to enjoyment of synchronous movements. Exploratory analyses of relationships between cortical activation and enjoyment and recognition implicated the sensorimotor cortices, which subserve action observation and aesthetic processing. These findings hold implications for clinical research and therapies seeking to foster successful social interaction.

Neural Correlates of Speech Comprehension in Normal Hearing Individuals and Cochlear Implant Users - An fNIRS Study in Quiet and Noisy Environments

This study investigates neural activity during a clinical hearing test transformed into a neuroimaging speech paradigm, focusing on individuals with cochlear implants (CIs) and normal hearing (NH) controls. Participants listened to sentences in quiet and noise conditions, and answered comprehension questions, while brain activation patterns were measured using functional near-infrared spectroscopy (fNIRS). NH participants exhibited effective strategies for speech comprehension in noise, with increased activity in left prefrontal regions. Good-performing CI users showed reduced accuracy and confidence, coupled with elevated listening effort in both conditions. Their brain activity in the bilateral temporal and left prefrontal regions were comparable to NH. Poor-performing CI users exhibited high effort and low accuracy in noise, with unclear brain activation patterns, suggesting cortical challenges in adapting to the auditory input provided by CIs.Clinical relevance- The study provides important insights into the compensatory strategies and cognitive demands of CI users during different hearing conditions. This contributes to our understanding of the neural aspects in speech processing for individuals with hearing loss and guide potential interventions and further improvement of devices to improve the auditory experience of CI users.

Inhibiting responses under the watch of a recently synchronized peer increases self-monitoring: evidence from functional near-infrared spectroscopy

Developing motor synchrony with a peer (through interventions such as the mirror game) can yield collaborative, cognitive and social benefits. However, it is also well established that observation by an audience can improve cognition. The combined and relative advantages offered by motor synchronization and audience effects are not yet understood. It is important to address this gap to determine the extent to which synchronizing activities might interact with the positive effects of an audience. In this preregistered study, we investigate the extent to which response inhibition may be improved when observed by a peer after motor synchronization with this peer. We compare behavioural and cortical (functional near-infrared spectroscopy; fNIRS) measures of inhibition between synchronized and non-synchronized dyads and find that the presence of a synchronized peer-audience introduces a speed-accuracy trade-off, consisting of slower reaction times and improved accuracy. This co-occurs with cortical activation in bilateral inferior frontal and middle prefrontal cortices, which are implicated in monitoring and maintenance of social alignment. Our findings have implications for carers and support people, who may benefit from synchronizing activities for rehabilitating inhibition and social skills in clinical settings.

Cortical haemodynamic responses predict individual ability to recognise vocal emotions with uninformative pitch cues but do not distinguish different emotions

We investigated the cortical representation of emotional prosody in normal-hearing listeners using functional near-infrared spectroscopy (fNIRS) and behavioural assessments. Consistent with previous reports, listeners relied most heavily on F0 cues when recognizing emotion cues; performance was relatively poor-and highly variable between listeners-when only intensity and speech-rate cues were available. Using fNIRS to image cortical activity to speech utterances containing natural and reduced prosodic cues, we found right superior temporal gyrus (STG) to be most sensitive to emotional prosody, but no emotion-specific cortical activations, suggesting that while fNIRS might be suited to investigating cortical mechanisms supporting speech processing it is less suited to investigating cortical haemodynamic responses to individual vocal emotions. Manipulating emotional speech to render F0 cues less informative, we found the amplitude of the haemodynamic response in right STG to be significantly correlated with listeners' abilities to recognise vocal emotions with uninformative F0 cues. Specifically, listeners more able to assign emotions to speech with degraded F0 cues showed lower haemodynamic responses to these degraded signals. This suggests a potential objective measure of behavioural sensitivity to vocal emotions that might benefit neurodiverse populations less sensitive to emotional prosody or hearing-impaired listeners, many of whom rely on listening technologies such as hearing aids and cochlear implants-neither of which restore, and often further degrade, the F0 cues essential to parsing emotional prosody conveyed in speech.