Misuse of the FNIRS Obfuscates Vigilance Cerebral Haemodynamics

Abstract

This review identifies cerebral haemodynamic fluctuations characteristic of vigilance decrement, the tendency for lapses in sustained attention to snowball with time on task. These characteristic fluctuations, previously missed by existent literature, can be ascribed to a series of methodological and analytic confounds associated with the use of Functional Near Infrared Spectroscopy (FNIRS) to record regional tissue oxygen saturation (rSO2) over the anterior frontal lobes during sustained attention tasks. This review triangulates a sequence of changes in rSO2 characteristic of vigilance decrement, that maps to bio-cognitive models of the human attention system. Previous studies may not have been able to identify this characteristic sequence, because data was either not recorded for a sufficient amount of time or used bucket averaging analysis methods that obfuscated changes in rSO2. Lessons learned through this review may reinform FNIRS research methods and ultimately lead future researchers to design experiments that better leverage rSO2 as a measure of human attentional performance.