Frequency-Domain Techniques for Cerebral and Functional Near-Infrared Spectroscopy

Frontiers in Neuroscience, Год журнала: 2020, Номер 14

Опубликована: Апрель 7, 2020

This article reviews the basic principles of frequency-domain near-infrared spectroscopy (FD-NIRS), which relies on intensity-modulated light sources and phase-sensitive optical detection, its non-invasive applications to brain. The simpler instrumentation more straightforward data analysis continuous-wave NIRS (CW-NIRS) accounts for fact that almost all current commercial instruments cerebral have embraced CW technique. However, FD-NIRS provides with richer information content, complements or exceeds capabilities CW-NIRS. One example is ability measure absolute properties (absorption reduced scattering coefficients) tissue, thus concentrations oxyhemoglobin deoxyhemoglobin in brain tissue. measured values such hemoglobin reported literature animal models human newborns, infants, children, adults. We also review application functional studies focused slower hemodynamic responses activity (time scale seconds) faster signals been linked neuronal activation 100 ms). Another power related different regions sensitivity featured by intensity phase data. report recent developments take advantage this feature maximize tissue relative superficial extracerebral (scalp, skull, etc.). contend latter capability a highly appealing quality FD-NIRS, measurements may result significant advances field sensing

Язык: Английский

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A Mini-Review on Functional Near-Infrared Spectroscopy (fNIRS): Where Do We Stand, and Where Should We Go?

Photonics, Год журнала: 2019, Номер 6(3), С. 87 - 87

Опубликована: Авг. 1, 2019

This mini-review is aimed at briefly summarizing the present status of functional near-infrared spectroscopy (fNIRS) and predicting where technique should go in next decade. quotes 33 articles on different fNIRS basics technical developments 44 reviews applications published last eight years. The huge number review about a wide spectrum topics field cognitive social sciences, neuroimaging research, medicine testifies to maturity achieved by this non-invasive optical vascular-based technique. Today, has started be utilized healthy subjects while moving freely naturalistic settings. Further instrumental are expected done near future fully satisfy latter important aspect. In addition, procedures, including correction methods for strong extracranial interferences, need standardized before using as clinical tool individual patients. New research avenues such interactive neurosciences, cortical activation modulated type sport performance, during neurofeedback training highlighted.

Язык: Английский

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Near-infrared II emissive metal clusters: From atom physics to biomedicine

Coordination Chemistry Reviews, Год журнала: 2021, Номер 448, С. 214184 - 214184

Опубликована: Сен. 7, 2021

Язык: Английский

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Bibliometric evaluation of 2000–2019 publications on functional near-infrared spectroscopy

NeuroImage, Год журнала: 2020, Номер 220, С. 117121 - 117121

Опубликована: Июнь 30, 2020

This study aimed to explore and analyze research trends frontiers on functional near-infrared spectroscopy (fNIRS) in the past 20 years identify collaboration networks. fNIRS-related publications from 2000 2019 were retrieved Web of Science database. A total 1727 satisfied search criteria. Bibliometric visualization analysis active authors, journals, institutions, countries, references, keywords conducted. The number annual related remarkably increased over years. Fallgatter published largest papers (83). Neuroimage not only had first 10 journals (157 articles) but also highest impact factor (IF, 2018 ​= ​5.812). University Tubingen United States ranked terms comprehensive influence this field. In recent years, burst (e.g., infant, social interaction, older adult) a series references with citation provided clues frontiers.

Язык: Английский

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Tai Chi Chuan exercise related change in brain function as assessed by functional near–infrared spectroscopy

Scientific Reports, Год журнала: 2019, Номер 9(1)

Опубликована: Сен. 13, 2019

Abstract Early studies have shown that Tai Chi Chuan (TCC) contributes to the rehabilitation of cognitive disorders and increases blood oxygen concentration levels in parietal occipital brain areas; however, mechanism TCC training on function remains poorly understood. This study hypothesize has altered aims explore effects functional connection effective prefrontal cortex (PFC), motor (MC), (OC). The participants were 23 experienced Chen–style practitioners (TCC group), 32 demographically matched TCC–naive healthy controls (control group). Functional connections calculated using wavelet–based coherence analysis dynamic Bayesian inference method, respectively. Results showed beyond intensity activity a particular cortical region induced by TCC, significant differences configuration connectivity observed between control groups during resting movement states. These findings suggested improved PFC, MC OC myogenic activity, sympathetic nervous system, endothelial cell metabolic activities; enhanced relayed ability improve cognition anti–memory decline potential.

Язык: Английский

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Evaluating a new generation of wearable high-density diffuse optical tomography technology via retinotopic mapping of the adult visual cortex

Neurophotonics, Год журнала: 2021, Номер 8(02)

Опубликована: Апрель 9, 2021

Significance: High-density diffuse optical tomography (HD-DOT) has been shown to approach the resolution and localization accuracy of blood oxygen level dependent-functional magnetic resonance imaging in adult brain by exploiting densely spaced, overlapping samples probed tissue volume, but technique date required large cumbersome fiber arrays. Aim: To evaluate a wearable HD-DOT system that provides comparable sampling density large, fiber-based systems, with vastly improved ergonomics. Approach: We investigated performance this replicating series classic visual stimulation paradigms, carried out one highly sampled participant during 15 sessions assess repeatability. Results: Hemodynamic response functions cortical activation maps replicate results obtained larger systems. Our demonstrate focal activations both oxyhemoglobin deoxyhemoglobin high degree repeatability observed across all sessions. A comparison simulated low-density array explicitly demonstrates improvements spatial localization, resolution, repeatability, image contrast can be high-density technology. Conclusions: The offers possibility for minimally constrained, spatially resolved functional human almost any environment holds particular promise enabling neuroscience applications outside laboratory setting. It also opens up new opportunities investigate populations unsuited traditional technologies.

Язык: Английский

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Cerebral perfusion and blood–brain barrier assessment in brain trauma using contrast-enhanced near-infrared spectroscopy with indocyanine green: A review

Journal of Cerebral Blood Flow & Metabolism, Год журнала: 2020, Номер 40(8), С. 1586 - 1598

Опубликована: Апрель 28, 2020

Contrast-enhanced near-infrared spectroscopy (NIRS) with indocyanine green (ICG) can be a valid non-invasive, continuous, bedside neuromonitoring tool. However, its usage in moderate and severe traumatic brain injury (TBI) patients unprecise due to their clinical status. This review is targeted at researchers clinicians involved the development application of contrast-enhanced NIRS for care TBI used design future studies. describes methods developed monitor perfusion blood–brain barrier integrity using changes diffuse reflectance during ICG passage results on studies animals humans. The limitations accuracy these when applied proposed solutions overcome them are discussed. Finally, analysis relative parameters as alternative over absolute values address some current needs trauma care. In conclusion, should taken translation optical signal into physiological patients, status must consideration. Discussion where how directed effectively incorporate given.

Язык: Английский

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Recent Developments in Instrumentation of Functional Near-Infrared Spectroscopy Systems

Applied Sciences, Год журнала: 2020, Номер 10(18), С. 6522 - 6522

Опубликована: Сен. 18, 2020

In the last three decades, development and steady improvement of various optical technologies at near-infrared region electromagnetic spectrum has inspired a large number scientists around world to design develop functional spectroscopy (fNIRS) systems for medical applications. This been driven further by availability new sources detectors that support very compact wearable system designs. this article, we review fNIRS from instrumentation point view, discussing associated challenges state-of-the-art approaches. beginning, fundamentals as well light-tissue interaction NIR are briefly introduced. After that, present basics instrumentation. Next, recent continuous-wave, frequency-domain, time-domain discussed. Finally, provide summary these modalities an outlook into future technology.

Язык: Английский

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New Directions in Exercise Prescription: Is There a Role for Brain-Derived Parameters Obtained by Functional Near-Infrared Spectroscopy?

Brain Sciences, Год журнала: 2020, Номер 10(6), С. 342 - 342

Опубликована: Июнь 3, 2020

In the literature, it is well established that regular physical exercise a powerful strategy to promote brain health and improve cognitive performance. However, exact knowledge about which prescription would be optimal in setting of exercise-cognition science lacking. While there strong theoretical rationale for using indicators internal load (e.g., heart rate) prescription, most suitable parameters have yet determined. this perspective article, we discuss role brain-derived activity) as valuable can beneficial individualizing research. Therefore, focus on application functional near-infrared spectroscopy (fNIRS), since neuroimaging modality provides specific advantages, making suited monitoring cortical hemodynamics proxy activity during exercise.

Язык: Английский

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Addressing the need for non-invasive lung assessment with time-resolved diffuse optics

Frontiers in Photonics, Год журнала: 2025, Номер 6

Опубликована: Март 10, 2025

Monitoring lungs functions is key for detecting several morbidities and pathologies. Photons in the 600–1,300 nm range might have potential to reach provide compositional functional information. Yet, few optical techniques been challenged non-invasively so far. In this paper, we investigate conditions probe using Time Domain Diffuse Optical Spectroscopy (TD-DOS). Counterintuitively, from Monte Carlo simulations discovered that a higher absorption coefficient chest wall as compared increases sensitivity deeper structures. vivo measurements on thorax of healthy volunteers during forced breathing protocol, complemented with information lung composition previously evaluated spectra porcine lung, suggest condition occurs above 1,100 nm. Multiple experimental setups were exploited cover spectral test different source-detector distances (3–7 cm). All exhibit oscillations consistent rhythm, suggesting detection expansion compression. However, marked differences subjects complex dependence detected signal photon time-of-flight seem allure non-trivial role propagation through lungs, related–for instance–to presence alveoli perhaps also overlying heterogeneous tissues. The unceasing development time-resolved single-photon detectors increasing performances 1,000 nm, better understanding optics– e.g. , anomalous diffusion models–will help unravel late, deep-travelling photons lead novel photonic tool non-invasively.

Язык: Английский

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