Objectives: This study aimed to investigate the early development of neural systems involved in the processing of non-verbal human emotional vocal signals, such as laughter and sighing, using functional magnetic resonance imaging.
Methods: Typically developing infants aged between 2 and 5 months were scanned using a fMRI passive listening task. They were played positive and negative nonverbal vocalisations, as well as neutral vocalisations and control sounds. Following pre-processing, fMRI volumes were mapped to an infant brain template.
Results: Preliminary group analyses suggest that frontal premotor, superior temporal and anterior cingulate areas are active in response to positively valenced vocalisations. Negatively valenced vocalisations activate cortical areas including posterior cingulate and superior temporal gyrus.
Conclusions: These results demonstrate that infant brain function is modulated by emotional sound, and in similar brain regions to adults. These include limbic structures, cortical 'motor preparatory' areas, and regions including mirror neurons. We plan further investigations into how infants who are at risk of neurodevelopmental disorders differ from neurotypical controls.