Optimizing spatial specificity and signal quality in fNIRS: an overview of potential challenges and possible options for improving the reliability of real-time applications

Frontiers in Neuroergonomics, Journal Year: 2024, Volume and Issue: 5

Published: June 5, 2024

The optical brain imaging method functional near-infrared spectroscopy (fNIRS) is a promising tool for real-time applications such as neurofeedback and brain-computer interfaces. Its combination of spatial specificity mobility makes it particularly attractive clinical use, both at the bedside in patients' homes. Despite these advantages, optimizing fNIRS use requires careful attention to two key aspects: ensuring good maintaining high signal quality. While detects superficial cortical regions, consistently reliably targeting specific regions interest can be challenging, studies that require repeated measurements. Variations cap placement coupled with limited anatomical information may further reduce this accuracy. Furthermore, important maintain quality contexts ensure they reflect true underlying activity. However, signals are susceptible contamination by cerebral extracerebral systemic noise well motion artifacts. Insufficient preprocessing therefore cause system run on instead aim review article help advance progress fNIRS-based applications. It highlights potential challenges improving quality, discusses possible options overcome challenges, addresses considerations relevant By addressing topics, aims improve planning execution future studies, thereby increasing their reliability repeatability.

Language: Английский

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Characterizing reproducibility of cerebral hemodynamic responses when applying short-channel regression in functional near-infrared spectroscopy

Neurophotonics, Journal Year: 2022, Volume and Issue: 9(01)

Published: March 7, 2022

Significance: Functional near-infrared spectroscopy (fNIRS) enables the measurement of brain activity noninvasively. Optical neuroimaging with fNIRS has been shown to be reproducible on group level and hence is an excellent research tool, but reproducibility single-subject still insufficient, challenging use for clinical applications. Aim: We investigated effect short-channel regression (SCR) as approach obtain measurements higher a level. SCR simultaneously considers contributions from long- short-separation channels removes confounding physiological changes through channel information. Approach: performed test-retest study hand grasping task in 15 healthy subjects using wearable device, optoHIVE. Relevant regions were localized transcranial magnetic stimulation ensure correct placement optodes. Reproducibility was assessed by intraclass correlation, correlation analysis, mixed effects modeling, classification accuracy task. Further, we characterized influence reproducibility. Results: found high (ICCsingle = 0.81 r 0.81). increased 0.64 (ICCsingle) did not affect (85% overall accuracy). Significant intersubject variability observed explained Mayer wave oscillations low raw signal strength. The signal-to-noise ratio (threshold at 40 dB) allowed distinguishing between persons weak strong activations. Conclusions: report, first time, that are our optoHIVE system improves In addition, give benchmark easily assess ability subject elicit sufficiently hemodynamic responses. With these insights, pave way reliable single neuroscientific

Language: Английский

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Gender differences in oxyhemoglobin (oxy-Hb) changes during drawing interactions in romantic couples: an fNIRS study

Frontiers in Behavioral Neuroscience, Journal Year: 2025, Volume and Issue: 18

Published: Jan. 13, 2025

Interpersonal interaction is essential to romantic couples. Understanding how gender impacts an individual’s brain activities during intimate crucial. The present study examined differences in oxyhemoglobin (oxy-Hb) changes real-time drawing interactions between members of couples using non-invasive functional near-infrared spectroscopy (fNIRS). We analyzed the oxy-Hb concentrations engaged interactive (i.e., chase and escape) non-interactive individual) sessions. Our findings indicated that males (vs. females) exhibited more pronounced Broca’s area, motor sensorimotor cortex, temporal lobe areas than women task, suggesting a heightened goal-oriented engagement social interaction. Significant positive correlations were found volumes area Quality Relationship Index (QRI), underscoring impact interpersonal dynamics on function tasks. This deepens understanding neural mechanisms tasks provides important insights for intimacy research.

Language: Английский

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Assessment of cortical activity, functional connectivity, and neuroplasticity in cerebral palsy using functional near‐infrared spectroscopy: A scoping review

Developmental Medicine & Child Neurology, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 18, 2025

Abstract Aim To map and critically appraise the literature on feasibility current use of functional near‐infrared spectroscopy (fNIRS) to assess cortical activity, connectivity, neuroplasticity in individuals with cerebral palsy (CP). Method A scoping review methodology was prospectively registered reported following Preferred Reporting Items for Systematic Meta‐Analysis Extension Scoping Reviews (PRISMA‐ScR) guidelines. systematic search conducted four databases. Empirical studies using fNIRS neural or CP aged 3 years older were included. Results Sixteen met inclusion criteria. Individuals (age range = 3–43 years; 70% unilateral CP) underwent fNIRS‐based assessment task‐evoked activity (studies [ n ] 15) and/or resting‐state connectivity ( 3). Preliminary observations suggest greater magnitude, extent, ipsilateral hemispheric lateralization sensorimotor cortex CP, while magnitude patterns prefrontal appear dependent task demands. Normalization metrics observed postintervention 3) paralleled improvements outcomes, highlighting their potential as promising biomarkers gains CP. Interpretation This details highlights research gaps technical limitations, offers recommendations support implementation ecologically valid neuroimaging

Language: Английский

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Cerebral Haemodynamic Assessment Following Sport-related Concussion (Mild Traumatic Brain Injury) in Youth and Amateur Rugby Union Players

Sports Medicine - Open, Journal Year: 2025, Volume and Issue: 11(1)

Published: May 2, 2025

Abstract Background Using functional near-infrared spectroscopy (fNIRS) as an objective diagnostic tool, we aimed to (1) compare fNIRS measurements in adult and youth male rugby players against controls over a playing season, 2) document the changes that occur concussed during England Rugby Football Union Graduated Return-To-Play programme (GRTP). Sixty-seven participants (rugby = 41 (26 adults: 27.5 ± 4.4 years; 15 youth: 16.5 0.6 control 26 (11 adult: 30.5 5.2 16.9 0.4 years) completed assessments at pre, mid end-season. Eight (five youth, three adult) sustained concussions, Graded Symptom Checklist from Sport Concussion Assessment Tool version 5 (SCAT5) assessment throughout GRTP period. Mixed linear models were utilised assess effect of group time on measures oxyhaemoglobin (∆O 2 Hb) deoxyhaemoglobin (∆HHb) performance tasks. Typical Error (TE) i.e., normal biological fluctuation measurement error, was calculated identify ‘cut-off’ thresholds for identifying effects concussion. Results There significant differences indices groups ( p < 0.05) but no between > 0.05). Seven out eight (87.5%) showed greater than TE period both ∆O Hb ∆HHb tasks these players’ profiles had not returned within ‘normal’ levels All symptom severity number Conclusion Current protocols alone are problematic there is need more individualised approach concussion management, utilising biomarker tools such fNIRS.

Language: Английский

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A Machine Learning Perspective on fNIRS Signal Quality Control Approaches

IEEE Transactions on Neural Systems and Rehabilitation Engineering, Journal Year: 2022, Volume and Issue: 30, P. 2292 - 2300

Published: Jan. 1, 2022

Despite a rise in the use of functional Near Infra-Red Spectroscopy (fNIRS) to study neural systems, fNIRS signal processing is not standardized and highly affected by empirical manual procedures. At beginning any procedure, Signal Quality Control (SQC) critical prevent errors unreliable results. In analysis, SQC currently relies on applying thresholds handcrafted Indicators (SQIs). this study, we dataset signals (N=1,340) recorded from 67 subjects, manually label quality subset segments (N=548) investigate pitfalls current practices while exploring opportunities provided Deep Learning approaches. We show that SQIs statistically discriminate with bad quality, but identification means lacks sensitivity. Alternatively thresholding, conventional machine learning models based have been proven more accurate, end-to-end approaches, Convolutional Neural Networks, capable further improving performance. The proposed approach, learning, represents objective for moves towards fully automated

Language: Английский

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Confounding effects of heart rate, breathing rate, and frontal fNIRS on interoception

Scientific Reports, Journal Year: 2022, Volume and Issue: 12(1)

Published: Nov. 30, 2022

Recent studies have established that cardiac and respiratory phases can modulate perception related neural dynamics. While heart rate sinus arrhythmia possibly affect interoception biomarkers, such as heartbeat-evoked potentials, the relative changes in cardiorespiratory dynamics interoceptive processes not yet been investigated. In this study, we investigated variation breathing rates, well higher functional including correlation frontal hemodynamics measured with fNIRS, during a heartbeat counting task. To further investigate physiology linked to vagal activity caused by specific performed task together controlled The results demonstrate focusing on heartbeats decreases rates comparison, which may be part of physiological mechanisms "listening" heart, focus attention, self-awareness. Focusing was also observed increase connectivity, supporting role structures monitoring visceral inputs. However, is affected both tasks. Based these results, concluded variations are confounding factors assessment abilities fluctuations should considered mode covariate measurement processes.

Language: Английский

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A Survey of Photoplethysmography and Imaging Photoplethysmography Quality Assessment Methods

Applied Sciences, Journal Year: 2022, Volume and Issue: 12(19), P. 9582 - 9582

Published: Sept. 23, 2022

Photoplethysmography is a method to visualize the variation in blood volume within tissues with light. The signal obtained has been used for monitoring of patients, interpretation diagnosis or extracting other physiological variables (e.g., pulse rate and oxygen saturation). However, photoplethysmography can be perturbed by external factors. Implementing methods evaluate quality allows one avoid misinterpretation while maintaining performance its applications. This paper provides an overview on index algorithms applied photoplethysmography. We try provide clear view role design. Then, we discuss challenges arising assessment imaging

Language: Английский

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Enhancement of Frequency-Specific Hemodynamic Power and Functional Connectivity by Transcranial Photobiomodulation in Healthy Humans

Frontiers in Neuroscience, Journal Year: 2022, Volume and Issue: 16

Published: June 10, 2022

Transcranial photobiomodulation (tPBM) has been considered a safe and effective brain stimulation modality being able to enhance cerebral oxygenation neurocognitive function. To better understand the underlying neurophysiological effects of tPBM in human brain, we utilized 111-channel functional near infrared spectroscopy (fNIRS) system map hemodynamic responses over whole head 8-min with 1,064-nm laser given on forehead 19 healthy participants. Instead analyzing broad-frequency signals (0-0.2 Hz), investigated frequency-specific three infra-slow oscillation (ISO) components consisting endogenic, neurogenic, myogenic vasomotions. Significant changes induced by spectral power oxygenated hemoglobin concentration (Δ[HbO]), connectivity (FC), global network metrics at each ISO frequency bands were identified mapped topographically for comparisons. Our novel findings revealed that significantly increased endogenic Δ[HbO] powers right frontopolar area site. Also, demonstrated enabled significant enhancements FC across cortical regions as well several metrics. These consistent recent reports met expectation is highly associated endothelial activity, which stimulated tPBM-evoked nitric oxide (NO) release.

Language: Английский

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Outcome measures in Angelman syndrome

Journal of Neurodevelopmental Disorders, Journal Year: 2024, Volume and Issue: 16(1)

Published: March 1, 2024

Angelman syndrome (AS) is a rare neurodevelopmental disorder characterized by severe intellectual disability, little to no expressive speech, visual and motor problems, emotional/behavioral challenges, tendency towards hyperphagia weight gain. The characteristics of AS make it difficult measure these children's functioning with standard clinical tests. Feasible outcome measures are needed current change over time, in practice trials. Our first aim assess the feasibility several functional We target domains neurocognitive physical growth using following measurement methods: eye-tracking, Near-Infrared Spectroscopy (fNIRS), indirect calorimetry, bio-impedance analysis (BIA), BOD POD (air-displacement plethysmography). second explore results above measures, order better understand phenotype. study sample consisted 28 children aged 2-18 years. defined an as feasible when (1) at least 70% participants successfully finished (2) 60% those had acceptable data quality. Adaptations test procedure reasons for early termination were noted. Parents rated acceptability importance invited recommendations increase feasibility. explored. Outcome obtained eye-tracking met definition feasibility, while fNIRS, BIA did not. most important measurements showing signs protest, inability sit still poor/no calibration (eye-tracking specific). Post-calibration was often applied obtain valid results. als fNIRS their child. All be important. Exploratory indicated longer reaction times high salient stimuli (eye-tracking) well body fat percentage (BOD POD). Eye-tracking methods AS. used orienting functions (with some practical adaptations) can potentially other outcomes well. examine composition. Registered d.d. 23-04-2020 under number 'NL8550' Dutch Trial Register: https://onderzoekmetmensen.nl/en/trial/23075.

Language: Английский

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