The application of fNIRS in studies on occupational workload: a systematic review

BackgroundOccupational workload can contribute to significant health problems such as chronic stress, fatigue and burnout. To investigate the underlying mechanisms, it is necessary to monitor brain activity in real work environments. Functional near-infrared spectroscopy (fNIRS) is a portable, non-i...

Full description

Saved in:
Bibliographic Details
Main Authors: Robin Gemmerich, Ole Müller, Andrea Schaller
Format: Article
Language:English
Published: Frontiers Media S.A. 2025-04-01
Series:Frontiers in Public Health
Subjects:
Online Access:https://www.frontiersin.org/articles/10.3389/fpubh.2025.1560605/full
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849710849690697728
author Robin Gemmerich
Ole Müller
Andrea Schaller
author_facet Robin Gemmerich
Ole Müller
Andrea Schaller
author_sort Robin Gemmerich
collection DOAJ
description BackgroundOccupational workload can contribute to significant health problems such as chronic stress, fatigue and burnout. To investigate the underlying mechanisms, it is necessary to monitor brain activity in real work environments. Functional near-infrared spectroscopy (fNIRS) is a portable, non-invasive neuroimaging method that captures neural correlates of occupational workload under natural conditions. However, despite its increasing application, a comprehensive overview of fNIRS-based research in this field is lacking. Therefore, this systematic review examines how fNIRS can be utilized to investigate occupational workload.MethodsFollowing PRISMA 2020 guidelines, we conducted our systematic review by searching Web of Science, PubMed, and Scopus between November 15, 2023 and March 20, 2025. We included all studies published in English or German at any date, as long as they examined healthy adult professionals performing occupational tasks with functional near-infrared spectroscopy (fNIRS). Extracted data included study characteristics, workload details, signal processing methods, main fNIRS findings, and study quality, assessed using the JBI Critical Appraisal Tool.ResultsWe included 41 studies. Of these, 23 reported a significant increase in oxygenated hemoglobin (HbO) concentration and functional connectivity in the prefrontal cortex (PFC) under higher occupational workload conditions. Only five studies examined typical office tasks. Nine studies analyzed differences in cortical activation between experts and novices, with experts showing increased HbO concentration in the PFC than novices. Regarding methodology, 26 studies used standardized optode placements, while only 17 applied systemic and extracerebral artifact correction. Small sample sizes and the absence of randomized controlled trials limited the reliability and reproducibility of the findings.ConclusionFunctional near-infrared spectroscopy effectively detects neural correlates of occupational workload and provides objective insights into cognitive demands in real-world work settings. Standardizing optode placement, harmonizing signal-processing methods, and increasing sample sizes would enhance the validity and comparability of future research. Expanding investigations to typical office environments is also crucial for understanding daily workload and for developing interventions that promote employee well-being and productivity. Overall, fNIRS represents a promising tool for establishing evidence-based workplace health promotion strategies across diverse occupational settings.
format Article
id doaj-art-aa54ddd87f4e44ed8698f5d1c37959a8
institution DOAJ
issn 2296-2565
language English
publishDate 2025-04-01
publisher Frontiers Media S.A.
record_format Article
series Frontiers in Public Health
spelling doaj-art-aa54ddd87f4e44ed8698f5d1c37959a82025-08-20T03:14:46ZengFrontiers Media S.A.Frontiers in Public Health2296-25652025-04-011310.3389/fpubh.2025.15606051560605The application of fNIRS in studies on occupational workload: a systematic reviewRobin Gemmerich0Ole Müller1Andrea Schaller2Department of Workplace Health Promotion and Prevention, University of the Bundeswehr Munich, Neubiberg, GermanyAgito Gesundheit GmbH, Cologne, GermanyDepartment of Workplace Health Promotion and Prevention, University of the Bundeswehr Munich, Neubiberg, GermanyBackgroundOccupational workload can contribute to significant health problems such as chronic stress, fatigue and burnout. To investigate the underlying mechanisms, it is necessary to monitor brain activity in real work environments. Functional near-infrared spectroscopy (fNIRS) is a portable, non-invasive neuroimaging method that captures neural correlates of occupational workload under natural conditions. However, despite its increasing application, a comprehensive overview of fNIRS-based research in this field is lacking. Therefore, this systematic review examines how fNIRS can be utilized to investigate occupational workload.MethodsFollowing PRISMA 2020 guidelines, we conducted our systematic review by searching Web of Science, PubMed, and Scopus between November 15, 2023 and March 20, 2025. We included all studies published in English or German at any date, as long as they examined healthy adult professionals performing occupational tasks with functional near-infrared spectroscopy (fNIRS). Extracted data included study characteristics, workload details, signal processing methods, main fNIRS findings, and study quality, assessed using the JBI Critical Appraisal Tool.ResultsWe included 41 studies. Of these, 23 reported a significant increase in oxygenated hemoglobin (HbO) concentration and functional connectivity in the prefrontal cortex (PFC) under higher occupational workload conditions. Only five studies examined typical office tasks. Nine studies analyzed differences in cortical activation between experts and novices, with experts showing increased HbO concentration in the PFC than novices. Regarding methodology, 26 studies used standardized optode placements, while only 17 applied systemic and extracerebral artifact correction. Small sample sizes and the absence of randomized controlled trials limited the reliability and reproducibility of the findings.ConclusionFunctional near-infrared spectroscopy effectively detects neural correlates of occupational workload and provides objective insights into cognitive demands in real-world work settings. Standardizing optode placement, harmonizing signal-processing methods, and increasing sample sizes would enhance the validity and comparability of future research. Expanding investigations to typical office environments is also crucial for understanding daily workload and for developing interventions that promote employee well-being and productivity. Overall, fNIRS represents a promising tool for establishing evidence-based workplace health promotion strategies across diverse occupational settings.https://www.frontiersin.org/articles/10.3389/fpubh.2025.1560605/fullfunctional near-infrared spectroscopyoccupational workloadreportingworkplace health promotionneuroimaging
spellingShingle Robin Gemmerich
Ole Müller
Andrea Schaller
The application of fNIRS in studies on occupational workload: a systematic review
Frontiers in Public Health
functional near-infrared spectroscopy
occupational workload
reporting
workplace health promotion
neuroimaging
title The application of fNIRS in studies on occupational workload: a systematic review
title_full The application of fNIRS in studies on occupational workload: a systematic review
title_fullStr The application of fNIRS in studies on occupational workload: a systematic review
title_full_unstemmed The application of fNIRS in studies on occupational workload: a systematic review
title_short The application of fNIRS in studies on occupational workload: a systematic review
title_sort application of fnirs in studies on occupational workload a systematic review
topic functional near-infrared spectroscopy
occupational workload
reporting
workplace health promotion
neuroimaging
url https://www.frontiersin.org/articles/10.3389/fpubh.2025.1560605/full
work_keys_str_mv AT robingemmerich theapplicationoffnirsinstudiesonoccupationalworkloadasystematicreview
AT olemuller theapplicationoffnirsinstudiesonoccupationalworkloadasystematicreview
AT andreaschaller theapplicationoffnirsinstudiesonoccupationalworkloadasystematicreview
AT robingemmerich applicationoffnirsinstudiesonoccupationalworkloadasystematicreview
AT olemuller applicationoffnirsinstudiesonoccupationalworkloadasystematicreview
AT andreaschaller applicationoffnirsinstudiesonoccupationalworkloadasystematicreview