The utility of NIRS technology for exploring emotional processing in children

Background: Deficits in emotional processing and, in particular, in emotional self-regulation represent non-specific risk factors for transdiagnostic poor outcomes. Researches have been focusing on the investigation of possible emotional processing and regulation biomarkers. The present brief review of the literature aims to evaluate whether NIRS signal might be one of them. Methods: We reviewed 8 original articles investigating children's hemodynamic response to emotional tasks using NIRS, or exploring the association between NIRS response to cognitive tasks and behavioral emotional regulation. Results: All the works revised found significant associations between NIRS data and emotional indexes. Furthermore, significant hemodynamic response is found in different age-groups (3–12 years of age), suggesting that cortical response to emotional processing as measured by NIRS is a marker consistently recognizable throughout the development. Limitations: Given that the studies in this field were still limited and used heterogeneous protocols, addressed different functions or aspects of emotional processing, these results are preliminary. Conclusions: NIRS seems a reliable tool to describe brain activation during emotional processing and regulation. Moreover, it seems to be particularly useful in studies including either developmental-aged participants or clinical samples, due to its clear advantages and non-intrusiveness, offering a potential marker for deficits in emotional processing and regulation.