Brain–Computer Interfacing Using Functional Near-Infrared Spectroscopy (fNIRS)

Biosensors, Год журнала: 2021, Номер 11(10), С. 389 - 389

Опубликована: Окт. 13, 2021

Functional Near-Infrared Spectroscopy (fNIRS) is a wearable optical spectroscopy system originally developed for continuous and non-invasive monitoring of brain function by measuring blood oxygen concentration. Recent advancements in brain-computer interfacing allow us to control the neuron combining it with fNIRS regulate cognitive function. In this review manuscript, we provide information regarding current advancement how provides advantages developing enable We also briefly discuss about can use technology further applications.

Язык: Английский

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Current opinions on the present and future use of functional near-infrared spectroscopy in psychiatry

Neurophotonics, Год журнала: 2023, Номер 10(01)

Опубликована: Фев. 7, 2023

Functional near-infrared spectroscopy (fNIRS) is an optical imaging technique for assessing human brain activity by noninvasively measuring the fluctuation of cerebral oxygenated- and deoxygenated-hemoglobin concentrations associated with neuronal activity. Owing to its superior mobility, low cost, good tolerance motion, past few decades have witnessed a rapid increase in research clinical use fNIRS variety psychiatric disorders. In this perspective article, we first briefly summarize state-of-the-art concerning psychiatry. particular, highlight diverse applications research, advanced development instruments, novel study designs exploring We then discuss some open challenges share our perspectives on future practice. conclude that holds promise becoming useful tool settings respect developing closed-loop systems improving individualized treatments diagnostics.

Язык: Английский

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Two-layered blood-lipid phantom and method to determine absorption and oxygenation employing changes in moments of DTOFs

Biomedical Optics Express, Год журнала: 2023, Номер 14(7), С. 3506 - 3506

Опубликована: Май 30, 2023

Near-infrared spectroscopy (NIRS) is an established technique for measuring tissue oxygen saturation (StO2), which of high clinical value. For tissues that have layered structures, it challenging but clinically relevant to obtain StO2 the different layers, e.g. brain and scalp. this aim, we present a new method data analysis time-domain NIRS (TD-NIRS) two-layered blood-lipid phantom. The enables accurate determination even large changes absorption coefficient (Δµa) in multiple layers. By adding Δµa baseline µa, provides absolute µa hence utilizes (i) statistical moments distributions times flight photons (DTOFs), (ii) analytical solution diffusion equation N-layered medium, (iii) Levenberg-Marquardt algorithm (LMA) determine layers from moments. suitable oximetry (relying on µa) as well functional (fNIRS) applications Δµa). Experiments were conducted phantom, enabled us simulate dynamic two first time. Two separate compartments, mimic superficial deep hold mixtures can be deoxygenated (using yeast) oxygenated (by bubbling oxygen) independently. Simultaneous measurements performed medium (variable layer thickness, L), (homogeneous), and/or (homogeneous). In experiments involving ink, increased nominal one compartments 0.05 0.25 cm-1, L set 14.5 mm. three blood (L 12, 15, or 17 mm), used protocol consisting six deoxygenation cycles. A state-of-the-art multi-wavelength TD-NIRS system measured simultaneously compartment reference. accurately determined (and StO2) both compartments. significant progress overcoming contamination layer, beneficial fNIRS applications, may improve head. advanced phantom assist ongoing effort towards more realistic standardized performance tests oximetry. Data MATLAB codes study made publicly available.

Язык: Английский

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A Portable Tool for Spectral Analysis of Plant Leaves That Incorporates a Multichannel Detector to Enable Faster Data Capture

Instruments, Год журнала: 2024, Номер 8(1), С. 24 - 24

Опубликована: Март 17, 2024

In this study, a novel system was designed to enhance the efficiency of data acquisition in portable and compact instrument dedicated spectral analysis various surfaces, including plant leaves, materials requiring characterization within 410 915 nm range. The proposed incorporates two nine-band detectors positioned on top bottom target surface, each equipped with digitally controllable LED. are capable measuring both reflection transmission properties, depending LED configuration. Specifically, when upper is activated, lower detector operates without its LED, enabling precise measurement light transmitted through sample. process reversed subsequent iterations, facilitating an accurate assessment for side surface. For reliability, error estimation utilizes color checker, followed by multi-layer perceptron (MLP) implementation integrated into microcontroller unit (MCU) using TinyML technology real-time refined acquisition. constructed 3D-printed components cost-effective electronics. It also supports USB or Bluetooth communication transmission. This innovative marks significant advancement analysis, particularly research, offering potential disease detection nutritional deficiency assessment.

Язык: Английский

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Neural system regulation of athletes based on FNIRS and thermal radiation images: Rehabilitation of motor function

Thermal Science and Engineering Progress, Год журнала: 2025, Номер unknown, С. 103293 - 103293

Опубликована: Янв. 1, 2025

Язык: Английский

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Time-domain NIRS system based on supercontinuum light source and multi-wavelength detection: validation for tissue oxygenation studies

Biomedical Optics Express, Год журнала: 2021, Номер 12(10), С. 6629 - 6629

Опубликована: Сен. 9, 2021

We present and validate a multi-wavelength time-domain near-infrared spectroscopy (TD-NIRS) system that avoids switching wavelengths instead exploits the full capability of supercontinuum light source by emitting acquiring signals for whole chosen range wavelengths. The was designed muscle brain oxygenation monitoring in clinical environment. A pulsed laser emits broadband each two detection modules acquires distributions times flight photons (DTOFs) 16 spectral channels (used width 12.5 nm / channel), providing total 32 DTOFs at up to 3 Hz. Two fibers fiber bundles allow simultaneous measurements positions on tissue or source-detector separations. Three established protocols (BIP, MEDPHOT, nEUROPt) were used quantitatively assess system's performance, including linearity, coupling, accuracy, depth sensitivity. Measurements performed homogeneous phantoms inhomogeneous (solid liquid). Furthermore, blood-lipid with varied amount blood Intralipid provide strongest validation accurate oximetry. retrieved hemoglobin concentrations oxygen saturation match well reference values obtained using commercially available NIRS (OxiplexTS) gas analyzer (ABL90 FLEX), except discrepancy occurs lowest Intralipid. In-vivo forearm three healthy volunteers during arterial (250 mmHg) venous (60 cuff occlusions an example expected hemodynamic changes follow previously well-described physiologies. All results, quantitative parameters, can be compared other systems report similar tests. Overall, presented TD-NIRS has exemplary performance evaluated state-of-the-art assessment methods.

Язык: Английский

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Optimization of Dual-Channel Near-Infrared Non-Invasive Glucose Level Measurement Sensors Based On Monte-Carlo Simulations

IEEE photonics journal, Год журнала: 2021, Номер 13(3), С. 1 - 9

Опубликована: Май 14, 2021

Non-invasive glucose monitoring sensors are promising techniques in diabetes management. In particular, optical-based near-infrared label-free, compact, user-friendly, and inexpensive. They require no daily calibration can provide continuous level monitoring. However, these still the development stage since their accuracy is not widely accepted by medical professionals. Here, we introduce an optimized dual-channel approach for this kind of sensor where four optodes short long channels employed. The channel signal that contains useful information about be utilized to calculate contents dermis layer skin while measure interference "noise" originating from epidermis layer. So, latter then removed signal. This work investigates optimal source-detector separation (SDS) both a wide range wavelengths 1200 nm 1900 nm. Based on sensitivity distributions layers signal-to-noise ratio, it suggested 2 mm SDS distance with wavelength 1450 potential choice channel. Moreover, 6 at 1750 may pave way further optimization non-invasive will adopted healthcare sector.

Язык: Английский

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K-Means Clustering Machine Learning Approach Reveals Groups of Homogeneous Individuals With Unique Brain Activation, Task, and Performance Dynamics Using fNIRS

IEEE Transactions on Neural Systems and Rehabilitation Engineering, Год журнала: 2023, Номер 31, С. 2535 - 2544

Опубликована: Янв. 1, 2023

Wearable functional near-infrared spectroscopy (fNIRS) for measuring brain function, in terms of hemodynamic responses, is pervading our everyday life and holds the potential to reliably classify cognitive load a naturalistic environment. However, human's response, behavior, task performance vary, even within across homogeneous individuals (with same training skill sets), which limits reliability any predictive model human. In context high-stakes tasks, such as military first-responder operations, real-time monitoring functions relating it ongoing task, outcomes, behavioral dynamics personnel teams invaluable. this work, portable wearable fNIRS system (WearLight) developed by author was upgraded, an experimental protocol designed image prefrontal cortex (PFC) area 25 healthy participants environment while performed n-back working memory (WM) tasks with four difficulty levels. The raw signals were processed using signal processing pipeline derive brain's responses. An unsupervised k-means machine learning (ML) clustering approach, utilizing task-induced responses input variables, suggested three unique participant groups. Task % correct, missing, reaction time, inverse efficiency score (IES), proposed IES extensively evaluated each Results showed that, on average, response increased, whereas degraded, increasing WM load. regression correlation analysis performance, (TPH) revealed interesting hidden characteristics variation TPH relationship between also served better scoring method that had distinct ranges different levels opposed overlapping scores traditional method. has find groups manner study underlying Using presented paper, soldiers, preferentially forming small units accomplish based insights goals may be helpful. results WearLight can PFC, suggests future directions multi-modal body sensor network (BSN) combining advanced ML algorithms state classification, physical prediction, mitigation degradation

Язык: Английский

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Estimation of the Differential Pathlength Factor for Human Skin Using Monte Carlo Simulations

Diagnostics, Год журнала: 2023, Номер 13(2), С. 309 - 309

Опубликована: Янв. 13, 2023

Near-infrared technology is an emerging non-invasive technique utilized for various medical applications. Recently, there have been many attempts to utilize NIR the continues monitoring of blood glucose levels through skin. Different approaches and designs proposed measurements. Light photons penetrating skin can undergo multiple scattering events, actual optical pathlength becomes larger than source-to-detector separation (optode spacing) in reflection-mode configuration. Thus, differential factor (DPF) must be incorporated into modified Beer-Lambert law. The accurate estimation DPF values will lead quantification physiological variations within tissue. In this work, aim was systematically estimate human a range separations wavelengths. Monte Carlo (MC) method mimic different layers with properties water volume fractions. This work could help improve accuracy near-infrared measurement

Язык: Английский

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The Core of Medical Imaging: State of the Art and Perspectives on the Detectors

Electronics, Год журнала: 2021, Номер 10(14), С. 1642 - 1642

Опубликована: Июль 10, 2021

In this review, the roles of detectors in various medical imaging techniques were described. Ultrasound, optical (near-infrared spectroscopy and coherence tomography) thermal imaging, magnetic resonance computed tomography, single-photon emission positron tomography modalities considered. For each methodology, state art mainly used systems was described, emphasizing new technologies applied.

Язык: Английский

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