An fNIRS study of brain state during letter and category fluency tasks

Abstract

Verbal Fluency Tasks (VFT) can be categorized into the Letter Fluency Task (LFT) that evaluates the ability to generate words starting with a particular letter, and the Category Fluency Task (CFT) that involves recall of words that belong to semantic categories. In this study, we investigated the differences in brain activity during LFT and CFT in healthy subjects. Brain activity in the frontal and the temporal region was measured using functional near-infrared spectroscopy with 40 channels. We observed more prominent brain activity when performing LFT than CFT.