fNIRS in Emotional Appraisal and the Dorsolateral Prefrontal Cortex: A Systematic Review

This study presents a systematic review on the use of functional near-infrared spectroscopy (fNIRS) in emotional tasks involving the prefrontal cortex (PFC), emphasizing the understanding of neurocognitive and emotional processes in various contexts through the measurement of oxygenation in the PFC as an indicator of brain activation.

To provide a detailed review of current research on the application of fNIRS to assess activity in the dorsolateral prefrontal cortex (DLPFC) during emotional processing tasks in adults.

A comprehensive literature search was conducted in PubMed, Scopus, and Web of Science databases, following PRISMA guidelines, with specific inclusion criteria and bias analysis. Study selection was based on methodological quality and thematic relevance, followed by data extraction and analysis.

The studied population includes healthy adults, and patients with mental disorders. The instruments and technical settings of fNIRS were diverse, and the emotional experiments involved various tasks, revealing patterns of brain activation in tasks that involve emotional processing; with altered left DLPFC activation can be observed in clinical populations, suggesting potential biomarkers of pathology. In contrast, right DLPFC activation in response to pleasant stimuli points to possible implications for future research and interventions related to cerebral laterality.

The review highlights the complexity of neurocognitive and emotional processes, underscoring the relevance of the DLPFC in psychology, neuroscience, and mental health. It also emphasizes the need to consider various contextual and methodological factors in future studies, such as adequate exposure time to tasks for optimal signal acquisition.