Near-infrared spectroscopic assessment of in vivo prefrontal activation in public speaking anxiety: A preliminary study.

Abstract

Public-speaking anxiety (PSA) may be associated with changes in functional activation of the right dorsolateral prefrontal cortex (DLPFC) during public speaking tasks. Research on the neural underpinnings of this disorder is limited by the physical restrictions imposed by conventional neuroimaging techniques. This study examined the feasibility of functional near-infrared spectroscopy (fNIRS) to investigate activation of the DLPFC in vivo while individuals gave a speech. Adults with PSA (n = 19) were assessed using self-rated anxiety measures during the anticipation and performance of a public speech while DLPFC activation was measured using fNIRS. Individuals showed bilateral changes in the DLPFC during both anticipation of and actual delivery of the speech. Only changes in blood volume in the right DLPFC were associated with higher subjective reports of anxiety during the speaking task. Results add to prior research examining DLPFC activation in generalized social anxiety disorder, and extend these findings to PSA for the first time. These findings highlight the utility of fNIRS for measuring cortical activation in vivo during social interactions. (PsycINFO Database Record (c) 2014 APA, all rights reserved) (journal abstract)