title: False positives and false negatives in functional near-infrared spectroscopy: issues, challenges, and the way forward.
abstract: We highlight a significant problem that needs to be considered and addressed when performing functional near-infrared spectroscopy (fNIRS) studies, namely the possibility of inadvertently measuring fNIRS hemodynamic responses that are not due to neurovascular coupling. These can be misinterpreted as brain activity, i.e., "false positives" (errors caused by wrongly assigning a detected hemodynamic response to functional brain activity), or mask brain activity, i.e., "false negatives" (errors caused by wrongly assigning a not observed hemodynamic response in the presence of functional brain activity). Here, we summarize the possible physiological origins of these issues and suggest ways to avoid and remove them.
authors.affiliation: University College London , Department of Medical Physics and Biomedical Engineering, Gower Street, Malet Place Engineering Building, WC1E 6BT, London, United Kingdom.
authors.forename: Ilias
authors.initials: I
authors.lastname: Tachtsidis
authors.affiliation: University Hospital Zurich, University of Zurich , Department of Neonatology, Biomedical Optics Research Laboratory, Frauenklinikstr. 10, 8091 Zurich, Switzerland.
authors.forename: Felix
authors.initials: F
authors.lastname: Scholkmann
keywords: functional near-infrared spectroscopy; hemodynamic response