Assessment of Attention in Extended Reality Using fNIRS: A Preliminary Literature Review

Attention is an essential cognitive process that involves maintaining alertness and selecting relevant information while filtering out distractions, enabling individuals to perform tasks safely and effectively. Neuroimaging techniques such as electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) have been widely used to assess an individual’s attentional state and functional efficiency. Functional near-infrared spectroscopy (fNIRS), a rapidly advancing, non-invasive neuroimaging technique, is typically lightweight, portable, easy to use, highly tolerant to movement, and less affected by electrical interference, making it particularly suitable for measuring attention during task performance in extended reality (XR) environments. This preliminary literature review surveyed recent studies assessing attention in head-mounted display (HMD) XR environments using fNIRS and examined specific attentional functions, attention tasks, brain regions of interest, and technical challenges reported. Findings suggest that integrating the two head-worn devices—fNIRS and HMD XR headset—may offer promising methods to assess attention in dynamic and ecologically valid XR environments. However, challenges remain, including competition in head surface area, added weight, and user discomfort. Notably, most studies focused on the frontal lobe, especially the prefrontal cortex.