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Ke Peng, Meryem A Yücel, Christopher M Aasted, Sarah C Steele, David A Boas, David Borsook, Lino Becerra
Currently, there is no method for providing a nonverbal objective assessment of pain. Recent work using functional near-infrared spectroscopy (fNIRS) has revealed its potential for objective measures. We conducted two fNIRS scans separated by 30 min and measured the hemodynamic response to the electrical noxious and innocuous stimuli over the anterior prefrontal cortex (aPFC) in 14 subjects. Based on the estimated hemodynamic response functions (HRFs), we first evaluated the test-retest reliability of using fNIRS in measuring the pain response over the aPFC...
January 2018: Neurophotonics
Suelen Rosa de Oliveira, Ana Carolina Cabral de Paula Machado, Jonas Jardim de Paula, Paulo Henrique Paiva de Moraes, Maria Juliana Silvério Nahin, Lívia de Castro Magalhães, Sergio L Novi, Rickson C Mesquita, Débora Marques de Miranda, Maria Cândida Ferrarez Bouzada
This study aimed to assess task-induced activation in motor cortex and its association with motor performance in full-term and preterm born infants at six months old. A cross-sectional study of 73 six-month-old infants was conducted (35 full-term and 38 preterm infants). Motor performance was assessed using the Bayley Scales of Infant Development third edition-Bayley-III. Brain hemodynamic activity during motor task was measured by functional near-infrared spectroscopy (fNIRS). Motor performance was similar in full-term and preterm infants...
January 2018: Neurophotonics
Amy Hirshkowitz, Marisa Biondi, Teresa Wilcox
Our ability to extract three-dimensional (3-D) object structure from motion-carried information is a basic visual capacity that is fundamental to object perception. Despite a rich body of behavioral work demonstrating that infants are sensitive to motion-carried information from the early months of life, little is known about the cortical networks that support infants' use of motion-carried information to extract 3-D object structure. This study assessed patterns of cortical activation in infants aged 4 to 6 months as they viewed two types of visual stimuli: (a) shape-from-motion (SFM) displays, where coherent motion of randomly distributed dots gave rise to the percept of 3-D shape and (b) random motion (RM) displays, where dots' motions lacked a coherent structure and gave rise to the percept of randomly moving dots...
January 2018: Neurophotonics
Gentaro Taga, Hama Watanabe, Fumitaka Homae
Spontaneous low-frequency oscillatory changes in oxygenated hemoglobin (oxy-Hb) and deoxygenated hemoglobin (deoxy-Hb) are observed using functional near-infrared spectroscopy (fNIRS). A previous study showed that the time-averaged phase difference between oxy-Hb and deoxy-Hb changes, referred to as hemoglobin phase of oxygenation and deoxygenation (hPod), is sensitive to the development of the cortex. We examined phase-locking index of hPod, referred to as [Formula: see text], in addition to hPod, in neonates and 3- and 6-month-old infants using the 94-channel fNIRS data, which covered large lateral regions of the cortex...
January 2018: Neurophotonics
Drew W R Halliday, Bryce P Mulligan, Douglas D Garrett, Stefan Schmidt, Sandra R Hundza, Mauricio A Garcia-Barrera, Robert S Stawski, Stuart W S MacDonald
OBJECTIVE: although the preponderance of research on functional brain activity investigates mean group differences, mounting evidence suggests that variability in neural activity is beneficial for optimal central nervous system (CNS) function. Independent of mean signal estimates, recent findings have shown that neural variability diminishes with age and is positively associated with cognitive performance, underscoring its adaptive nature. The present investigation sought to employ functional near infrared spectroscopy (fNIRS) to derive two operationalizations of cerebral oxygenation, representing mean and variability [using standard deviation (SD)] in neural activity, and to specifically contrast these mean- and SD-oxyhemoglobin (HbO) estimates as predictors of cognitive function...
January 2018: Neurophotonics
Hubin Zhao, Robert J Cooper
The development of a whole-scalp, high sampling-density diffuse optical tomography (DOT) system is a critical next step in the evolution of the field of diffuse optics. To achieve this with optical fiber bundles is extremely challenging, simply because of the sheer number of bundles required, and the associated challenges of weight and ergonomics. Dispensing with optical fiber bundles and moving to head-mounted optoelectronics can potentially facilitate the advent of a new generation of wearable, whole-scalp technologies that will open up a range of new experimental and clinical applications for diffuse optical measurements...
January 2018: Neurophotonics
David Perpetuini, Roberta Bucco, Michele Zito, Arcangelo Merla
Working memory deficit is a signature of Alzheimer's disease (AD). The free and cued selective reminding test (FCSRT) is a clinical test that quantifies memory deficit for AD diagnosis. However, the diagnostic accuracy of FCSRT may be increased by accompanying it with neuroimaging. Since the test requires doctor-patient interaction, brain monitoring is challenging. Functional near-infrared spectroscopy (fNIRS) could be suited for such a purpose because of the fNIRS flexibility. We investigated whether the complexity, based on sample entropy and multiscale entropy metrics, of the fNIRS signal during FCSRT was correlated with memory deficit in early AD...
January 2018: Neurophotonics
Davide Tamborini, Parisa Farzam, Bernhard Zimmermann, Kuan-Cheng Wu, David A Boas, Maria Angela Franceschini
This paper presents a multidistance and multiwavelength diffuse correlation spectroscopy (DCS) approach and its implementation to simultaneously measure the optical proprieties of deep tissue as well as the blood flow. The system consists of three long coherence length lasers at different wavelengths in the near-infrared, eight single-photon detectors, and a correlator board. With this approach, we collect both light intensity and DCS data at multiple distances and multiple wavelengths, which provide unique information to fit for all the parameters of interest: scattering, blood flow, and hemoglobin concentration...
January 2018: Neurophotonics
Felipe Orihuela-Espina, Daniel R Leff, David R C James, Ara W Darzi, Guang-Zhong Yang
This paper describes the Imperial College near infrared spectroscopy neuroimaging analysis (ICNNA) software tool for functional near infrared spectroscopy neuroimaging data. ICNNA is a MATLAB-based object-oriented framework encompassing an application programming interface and a graphical user interface. ICNNA incorporates reconstruction based on the modified Beer-Lambert law and basic processing and data validation capabilities. Emphasis is placed on the full experiment rather than individual neuroimages as the central element of analysis...
January 2018: Neurophotonics
Ashley C Whiteman, Hendrik Santosa, Daniel F Chen, Susan Perlman, Theodore Huppert
Functional near-infrared spectroscopy (fNIRS) is a noninvasive brain imaging technique that uses scalp-placed light sensors to measure evoked changes in cerebral blood oxygenation. The portability, low overhead cost, and ability to use this technology under a wide range of experimental environments make fNIRS well-suited for studies involving infants and children. However, since fNIRS does not directly provide anatomical or structural information, these measurements may be sensitive to individual or group level differences associated with variations in head size, depth of the brain from the scalp, or other anatomical factors affecting the penetration of light into the head...
January 2018: Neurophotonics
Xinlong Wang, Divya D Reddy, Sahil S Nalawade, Suvra Pal, F Gonzalez-Lima, Hanli Liu
Transcranial infrared laser stimulation (TILS) has shown effectiveness in improving human cognition and was investigated using broadband near-infrared spectroscopy (bb-NIRS) in our previous study, but the effect of laser heating on the actual bb-NIRS measurements was not investigated. To address this potential confounding factor, 11 human participants were studied. First, we measured time-dependent temperature increases on forehead skin using clinical-grade thermometers following the TILS experimental protocol used in our previous study...
January 2018: Neurophotonics
Thanawin Trakoolwilaiwan, Bahareh Behboodi, Jaeseok Lee, Kyungsoo Kim, Ji-Woong Choi
The aim of this work is to develop an effective brain-computer interface (BCI) method based on functional near-infrared spectroscopy (fNIRS). In order to improve the performance of the BCI system in terms of accuracy, the ability to discriminate features from input signals and proper classification are desired. Previous studies have mainly extracted features from the signal manually, but proper features need to be selected carefully. To avoid performance degradation caused by manual feature selection, we applied convolutional neural networks (CNNs) as the automatic feature extractor and classifier for fNIRS-based BCI...
January 2018: Neurophotonics
Tsukasa Funane, Takashi Numata, Hiroki Sato, Shinsuke Hiraizumi, Yuichi Hasegawa, Hidenobu Kuwabara, Kiyoshi Hasegawa, Masashi Kiguchi
We developed a system-on-chip (SoC)-incorporated light-emitting diode (LED) and avalanche photodiode (APD) modules to improve the usability and flexibility of a fiberless wearable functional near-infrared spectroscopy (fNIRS) system. The SoC has a microprocessing unit and programmable circuits. The time division method and the lock-in method were used for separately detecting signals from different positions and signals of different wavelengths, respectively. Each module autonomously works for this time-divided-lock-in measurement with a high sensitivity for haired regions...
January 2018: Neurophotonics
Swethasri Dravida, Jack Adam Noah, Xian Zhang, Joy Hirsch
Functional near-infrared spectroscopy (fNIRS) could be well suited for clinical use, such as measuring neural activity before and after treatment; however, reliability and specificity of fNIRS signals must be ensured so that differences can be attributed to the intervention. This study compared the test-retest and longitudinal reliability of oxyhemoglobin and deoxyhemoglobin signals before and after spatial filtering. In the test-retest experiment, 14 participants were scanned on 2 days while performing four right-handed digit-manipulation tasks...
January 2018: Neurophotonics
Aykut Eken, Murat Kara, Bora Baskak, Ayşegül Baltacı, Didem Gökçay
Using functional near-infrared spectroscopy (fNIRS), modulation of hemodynamic responses by transcutaneous electrical nerve stimulation (TENS) during delivery of nociceptive stimulation was investigated in fibromyalgia (FM) patients and healthy controls for both hands. Two experiments were conducted: (1) median nerve stimulation with TENS and (2) painful stimulation using electronic von Frey filaments with TENS/placebo TENS. Mean [Formula: see text] brain activity was compared across groups and conditions using factorial ANOVA...
January 2018: Neurophotonics
Benjamin D Zinszer, Laurie Bayet, Lauren L Emberson, Rajeev D S Raizada, Richard N Aslin
This study uses representational similarity-based neural decoding to test whether semantic information elicited by words and pictures is encoded in functional near-infrared spectroscopy (fNIRS) data. In experiment 1, subjects passively viewed eight audiovisual word and picture stimuli for 15 min. Blood oxygen levels were measured using the Hitachi ETG-4000 fNIRS system with a posterior array over the occipital lobe and a left lateral array over the temporal lobe. Each participant's response patterns were abstracted to representational similarity space and compared to the group average (excluding that subject, i...
January 2018: Neurophotonics
Guilherne Augusto Zimeo Morais, Felix Scholkmann, Joana Bisol Balardin, Rogério Akira Furucho, Renan Costa Vieira de Paula, Claudinei Eduardo Biazoli, João Ricardo Sato
Several functional near-infrared spectroscopy (fNIRS) studies report their findings based on changes of a single chromophore, usually concentration changes of oxygenated hemoglobin ([[Formula: see text]]) or deoxygenated hemoglobin (HHb). However, influence of physiological actions may differ depending on which element is considered and the assumption that the chosen measure correlates with the neural response of interest might not hold. By assessing the correlation between [[Formula: see text]] and [HHb] in task-evoked activity as well as resting-state data, we identified a spatial dependency of non-neuronal hemodynamic changes in the anterior temporal region of the human head...
January 2018: Neurophotonics
Robert H Wilson, Christian Crouzet, Mohammad Torabzadeh, Afsheen Bazrafkan, Maryam H Farahabadi, Babak Jamasian, Dishant Donga, Juan Alcocer, Shuhab M Zaher, Bernard Choi, Yama Akbari, Bruce J Tromberg
Quantifying rapidly varying perturbations in cerebral tissue absorption and scattering can potentially help to characterize changes in brain function caused by ischemic trauma. We have developed a platform for rapid intrinsic signal brain optical imaging using macroscopically structured light. The device performs fast, multispectral, spatial frequency domain imaging (SFDI), detecting backscattered light from three-phase binary square-wave projected patterns, which have a much higher refresh rate than sinusoidal patterns used in conventional SFDI...
October 2017: Neurophotonics
Hyounguk Jang, Stanley Huang, Daniel X Hammer, Lin Wang, Harmain Rafi, Meijun Ye, Cristin G Welle, Jonathan A N Fisher
Following acute traumatic brain injury (TBI), timely transport to a hospital can significantly improve the prognosis for recovery. There is, however, a dearth of quantitative biomarkers for brain injury that can be rapidly acquired and interpreted in active, field environments in which TBIs are frequently incurred. We explored potential functional indicators for TBI that can be noninvasively obtained through portable detection modalities, namely optical and electrophysiological approaches. By combining diffuse correlation spectroscopy with colocalized electrophysiological measurements in a mouse model of TBI, we observed concomitant alterations in sensory-evoked cerebral blood flow (CBF) and electrical potentials following controlled cortical impact...
October 2017: Neurophotonics
David A Boas
This editorial introduces the Special issue from SPIE Brain 2017.
October 2017: Neurophotonics
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