Using Fiberless, Wearable fNIRS to Monitor Brain Activity in Real-world Cognitive Tasks

TLDR

Functional Near‑Infrared Spectroscopy (fNIRS) uses near‑infrared light to detect haemoglobin changes linked to neuronal activity, offering a portable, lightweight, motion‑tolerant imaging modality with good spatial and temporal resolution that is suitable for diverse cognitive tasks and populations, and recent fiberless devices enable real‑world neuroscience studies. This study investigates the feasibility of fiberless fNIRS for monitoring brain activity during a real‑world prospective memory task. The protocol records continuous prefrontal cortex haemoglobin concentration changes while participants walk and perform multiple tasks outside the laboratory.

Abstract

Functional Near Infrared Spectroscopy (fNIRS) is a neuroimaging technique that uses near-infrared light to monitor brain activity. Based on neurovascular coupling, fNIRS is able to measure the haemoglobin concentration changes secondary to neuronal activity. Compared to other neuroimaging techniques, fNIRS represents a good compromise in terms of spatial and temporal resolution. Moreover, it is portable, lightweight, less sensitive to motion artifacts and does not impose significant physical restraints. It is therefore appropriate to monitor a wide range of cognitive tasks (e.g., auditory, gait analysis, social interaction) and different age populations (e.g., new-borns, adults, elderly people). The recent development of fiberless fNIRS devices has opened the way to new applications in neuroscience research. This represents a unique opportunity to study functional activity during real-world tests, which can be more sensitive and accurate in assessing cognitive function and dysfunction than lab-based tests. This study explored the use of fiberless fNIRS to monitor brain activity during a real-world prospective memory task. This protocol is performed outside the lab and brain haemoglobin concentration changes are continuously measured over the prefrontal cortex while the subject walks around in order to accomplish several different tasks.