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Holmes M, Aalto D, Cummine J. Opening the dialogue: A preliminary exploration of hair color, hair cleanliness, light, and motion effects on fNIRS signal quality. PLoS One 2024; 19:e0304356. [PMID: 38781258 PMCID: PMC11115287 DOI: 10.1371/journal.pone.0304356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Accepted: 05/12/2024] [Indexed: 05/25/2024] Open
Abstract
INTRODUCTION Functional near-infrared spectroscopy (fNIRS) is a promising tool for studying brain activity, offering advantages such as portability and affordability. However, challenges in data collection persist due to factors like participant physiology, environmental light, and gross-motor movements, with limited literature on their impact on fNIRS signal quality. This study addresses four potentially influential factors-hair color, hair cleanliness, environmental light, and gross-motor movements-on fNIRS signal quality. Our aim is to raise awareness and offer insights for future fNIRS research. METHODS Six participants (4 Females, 2 Males) took part in four different experiments investigating the effects of hair color, hair cleanliness, environmental light, and gross-motor movements on fNIRS signal quality. Participants in Experiment 1, categorized by hair color, completed a finger-tapping task in a between-subjects block design. Signal quality was compared between each hair color. Participants in Experiments 2 and 3 completed a finger-tapping task in a within-subjects block design, with signal quality being compared across hair cleanliness (i.e., five consecutive days without washing the hair) and environmental light (i.e., sunlight, artificial light, no light, etc.), respectively. Experiment 4 assessed three gross-motor movements (i.e., walking, turning and nodding the head) in a within-subjects block design. Motor movements were then compared to resting blocks. Signal quality was evaluated using Scalp Coupling Index (SCI) measurements. RESULTS Lighter hair produced better signals than dark hair, while the impact of environmental light remains uncertain. Hair cleanliness showed no significant effects, but gross motor movements notably reduced signal quality. CONCLUSION Our results suggest that hair color, environmental light, and gross-motor movements affect fNIRS signal quality while hair cleanliness does not. Nevertheless, future studies with larger sample sizes are warranted to fully understand these effects. To advance future research, comprehensive documentation of participant demographics and lab conditions, along with signal quality analyses, is essential.
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Affiliation(s)
- Mitchell Holmes
- Faculty of Rehabilitation Medicine, University of Alberta, Edmonton, Alberta, Canada
| | - Daniel Aalto
- Faculty of Medicine and Dentistry, Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada
- Faculty of Rehabilitation Medicine, Department of Communication Sciences and Disorders, University of Alberta, Edmonton, Alberta, Canada
- Institute for Reconstructive Science in Medicine (iRSM), Misericordia Community Hospital, Edmonton, Alberta, Canada
| | - Jacqueline Cummine
- Faculty of Medicine and Dentistry, Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada
- Faculty of Rehabilitation Medicine, Department of Communication Sciences and Disorders, University of Alberta, Edmonton, Alberta, Canada
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2
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Robinson MB, Cheng TY, Renna M, Wu MM, Kim B, Cheng X, Boas DA, Franceschini MA, Carp SA. Comparing the performance potential of speckle contrast optical spectroscopy and diffuse correlation spectroscopy for cerebral blood flow monitoring using Monte Carlo simulations in realistic head geometries. NEUROPHOTONICS 2024; 11:015004. [PMID: 38282721 PMCID: PMC10821780 DOI: 10.1117/1.nph.11.1.015004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Revised: 12/13/2023] [Accepted: 01/08/2024] [Indexed: 01/30/2024]
Abstract
Significance The non-invasive measurement of cerebral blood flow based on diffuse optical techniques has seen increased interest as a research tool for cerebral perfusion monitoring in critical care and functional brain imaging. Diffuse correlation spectroscopy (DCS) and speckle contrast optical spectroscopy (SCOS) are two such techniques that measure complementary aspects of the fluctuating intensity signal, with DCS quantifying the temporal fluctuations of the signal and SCOS quantifying the spatial blurring of a speckle pattern. With the increasing interest in the use of these techniques, a thorough comparison would inform new adopters of the benefits of each technique. Aim We systematically evaluate the performance of DCS and SCOS for the measurement of cerebral blood flow. Approach Monte Carlo simulations of dynamic light scattering in an MRI-derived head model were performed. For both DCS and SCOS, estimates of sensitivity to cerebral blood flow changes, coefficient of variation of the measured blood flow, and the contrast-to-noise ratio of the measurement to the cerebral perfusion signal were calculated. By varying complementary aspects of data collection between the two methods, we investigated the performance benefits of different measurement strategies, including altering the number of modes per optical detector, the integration time/fitting time of the speckle measurement, and the laser source delivery strategy. Results Through comparison across these metrics with simulated detectors having realistic noise properties, we determine several guiding principles for the optimization of these techniques and report the performance comparison between the two over a range of measurement properties and tissue geometries. We find that SCOS outperforms DCS in terms of contrast-to-noise ratio for the cerebral blood flow signal in the ideal case simulated here but note that SCOS requires careful experimental calibrations to ensure accurate measurements of cerebral blood flow. Conclusion We provide design principles by which to evaluate the development of DCS and SCOS systems for their use in the measurement of cerebral blood flow.
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Affiliation(s)
- Mitchell B. Robinson
- Massachusetts General Hospital, Harvard Medical School, Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Boston, Massachusetts, United States
| | - Tom Y. Cheng
- Massachusetts General Hospital, Harvard Medical School, Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Boston, Massachusetts, United States
- Boston University, Neurophotonics Center, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - Marco Renna
- Massachusetts General Hospital, Harvard Medical School, Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Boston, Massachusetts, United States
| | - Melissa M. Wu
- Duke University, Department of Biomedical Engineering, Durham, North Carolina, United States
| | - Byungchan Kim
- Boston University, Neurophotonics Center, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - Xiaojun Cheng
- Boston University, Neurophotonics Center, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - David A. Boas
- Boston University, Neurophotonics Center, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - Maria Angela Franceschini
- Massachusetts General Hospital, Harvard Medical School, Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Boston, Massachusetts, United States
| | - Stefan A. Carp
- Massachusetts General Hospital, Harvard Medical School, Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Boston, Massachusetts, United States
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Vorreuther A, Bastian L, Benitez Andonegui A, Evenblij D, Riecke L, Lührs M, Sorger B. It takes two (seconds): decreasing encoding time for two-choice functional near-infrared spectroscopy brain-computer interface communication. NEUROPHOTONICS 2023; 10:045005. [PMID: 37928600 PMCID: PMC10620514 DOI: 10.1117/1.nph.10.4.045005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/15/2023] [Revised: 07/25/2023] [Accepted: 08/18/2023] [Indexed: 11/07/2023]
Abstract
Significance Brain-computer interfaces (BCIs) can provide severely motor-impaired patients with a motor-independent communication channel. Functional near-infrared spectroscopy (fNIRS) constitutes a promising BCI-input modality given its high mobility, safety, user comfort, cost-efficiency, and relatively low motion sensitivity. Aim The present study aimed at developing an efficient and convenient two-choice fNIRS communication BCI by implementing a relatively short encoding time (2 s), considerably increasing communication speed, and decreasing the cognitive load of BCI users. Approach To encode binary answers to 10 biographical questions, 10 healthy adults repeatedly performed a combined motor-speech imagery task within 2 different time windows guided by auditory instructions. Each answer-encoding run consisted of 10 trials. Answers were decoded during the ongoing experiment from the time course of the individually identified most-informative fNIRS channel-by-chromophore combination. Results The answers of participants were decoded online with an accuracy of 85.8% (run-based group mean). Post-hoc analysis yielded an average single-trial accuracy of 68.1%. Analysis of the effect of number of trial repetitions showed that the best information-transfer rate could be obtained by combining four encoding trials. Conclusions The study demonstrates that an encoding time as short as 2 s can enable immediate, efficient, and convenient fNIRS-BCI communication.
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Affiliation(s)
- Anna Vorreuther
- Maastricht University, Department of Cognitive Neuroscience, Maastricht, The Netherlands
- University of Stuttgart, Institute of Human Factors and Technology Management IAT, Applied Neurocognitive Systems, Stuttgart, Germany
| | - Lisa Bastian
- Maastricht University, Department of Cognitive Neuroscience, Maastricht, The Netherlands
- University of Tübingen, Institute of Medical Psychology and Behavioral Neurobiology, Tübingen, Germany
- International Max Planck Research School, Graduate Training Centre of Neuroscience, Tübingen, Germany
| | - Amaia Benitez Andonegui
- Maastricht University, Department of Cognitive Neuroscience, Maastricht, The Netherlands
- NIH, MEG Core Facility National Institute of Mental Health, Bethesda, Maryland, United States
| | - Danielle Evenblij
- Maastricht University, Department of Cognitive Neuroscience, Maastricht, The Netherlands
| | - Lars Riecke
- Maastricht University, Department of Cognitive Neuroscience, Maastricht, The Netherlands
| | - Michael Lührs
- Maastricht University, Department of Cognitive Neuroscience, Maastricht, The Netherlands
- Brain Innovation B.V., Research Department, Maastricht, The Netherlands
| | - Bettina Sorger
- Maastricht University, Department of Cognitive Neuroscience, Maastricht, The Netherlands
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Kwasa J, Peterson HM, Karrobi K, Jones L, Parker T, Nickerson N, Wood S. Demographic reporting and phenotypic exclusion in fNIRS. Front Neurosci 2023; 17:1086208. [PMID: 37229429 PMCID: PMC10203458 DOI: 10.3389/fnins.2023.1086208] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Accepted: 04/05/2023] [Indexed: 05/27/2023] Open
Abstract
Functional near-infrared spectroscopy (fNIRS) promises to be a leading non-invasive neuroimaging method due to its portability and low cost. However, concerns are rising over its inclusivity of all skin tones and hair types (Parker and Ricard, 2022, Webb et al., 2022). Functional NIRS relies on direct contact of light-emitting optodes to the scalp, which can be blocked more by longer, darker, and especially curlier hair. Additionally, NIR light can be attenuated by melanin, which is accounted for in neither fNIRS hardware nor analysis methods. Recent work has shown that overlooking these considerations in other modalities like EEG leads to the disproportionate exclusion of individuals with these phenotypes-especially Black people-in both clinical and research literature (Choy, 2020; Bradford et al., 2022; Louis et al., 2023). In this article, we sought to determine if (Jöbsis, 1977) biomedical optics developers and researchers report fNIRS performance variability between skin tones and hair textures, (2a) fNIRS neuroscience practitioners report phenotypic and demographic details in their articles, and thus, (2b) is a similar pattern of participant exclusion found in EEG also present in the fNIRS literature. We present a literature review of top Biomedical Optics and Human Neuroscience journals, showing that demographic and phenotypic reporting is unpopular in both fNIRS development and neuroscience applications. We conclude with a list of recommendations to the fNIRS community including examples of Black researchers addressing these issues head-on, inclusive best practices for fNIRS researchers, and recommendations to funding and regulatory bodies to achieve an inclusive neuroscience enterprise in fNIRS and beyond.
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Affiliation(s)
- Jasmine Kwasa
- Neuroscience Institute, Carnegie Mellon University, Pittsburgh, PA, United States
| | - Hannah M. Peterson
- Center for Systems Biology, Massachusetts General Hospital, Boston, MA, United States
| | - Kavon Karrobi
- Department of Biomedical Engineering, Boston University, Boston, MA, United States
| | - Lietsel Jones
- Burnett School of Biomedical Sciences, University of Central Florida, Orlando, FL, United States
| | - Termara Parker
- Interdepartmental Neuroscience Program, School of Medicine, Yale University, New Haven, CT, United States
| | - Nia Nickerson
- Combined Program in Education and Psychology, University of Michigan, Ann Arbor, MI, United States
| | - Sossena Wood
- Neuroscience Institute, Carnegie Mellon University, Pittsburgh, PA, United States
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, PA, United States
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Nicolson F, Kircher MF, Stone N, Matousek P. Spatially offset Raman spectroscopy for biomedical applications. Chem Soc Rev 2021; 50:556-568. [PMID: 33169761 PMCID: PMC8323810 DOI: 10.1039/d0cs00855a] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Indexed: 12/24/2022]
Abstract
In recent years, Raman spectroscopy has undergone major advancements in its ability to probe deeply through turbid media such as biological tissues. This progress has been facilitated by the advent of a range of specialist techniques based around spatially offset Raman spectroscopy (SORS) to enable non-invasive probing of living tissue through depths of up to 5 cm. This represents an improvement in depth penetration of up to two orders of magnitude compared to what can be achieved with conventional Raman methods. In combination with the inherently high molecular specificity of Raman spectroscopy, this has therefore opened up entirely new prospects for a range of new analytical applications across multiple fields including medical diagnosis and disease monitoring. This article discusses SORS and related variants of deep Raman spectroscopy such as transmission Raman spectroscopy (TRS), micro-SORS and surface enhanced spatially offset Raman spectroscopy (SESORS), and reviews the progress made in this field during the past 5 years including advances in non-invasive cancer diagnosis, monitoring of neurotransmitters, and assessment of bone disease.
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Affiliation(s)
- Fay Nicolson
- Department of Imaging, Dana-Farber Cancer Institute & Harvard Medical SchoolBostonMA 02215USA
| | - Moritz F. Kircher
- Department of Imaging, Dana-Farber Cancer Institute & Harvard Medical SchoolBostonMA 02215USA
- Department of Radiology, Brigham & Women's Hospital & Harvard Medical SchoolBostonMA 022115USA
| | - Nick Stone
- School of Physics and Astronomy, University of ExeterExeterEX4 4QLUK
- Royal Devon and Exeter NHS Foundation TrustBarrack RoadExeterDevonEX2 5DWUK
| | - Pavel Matousek
- Central Laser Facility, Research Complex at Harwell, STFC Rutherford Appleton Laboratory, UKRIHarwellOxfordOX11 0QXUK
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Nagels-Coune L, Benitez-Andonegui A, Reuter N, Lührs M, Goebel R, De Weerd P, Riecke L, Sorger B. Brain-Based Binary Communication Using Spatiotemporal Features of fNIRS Responses. Front Hum Neurosci 2020; 14:113. [PMID: 32351371 PMCID: PMC7174771 DOI: 10.3389/fnhum.2020.00113] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2019] [Accepted: 03/12/2020] [Indexed: 12/14/2022] Open
Abstract
“Locked-in” patients lose their ability to communicate naturally due to motor system dysfunction. Brain-computer interfacing offers a solution for their inability to communicate by enabling motor-independent communication. Straightforward and convenient in-session communication is essential in clinical environments. The present study introduces a functional near-infrared spectroscopy (fNIRS)-based binary communication paradigm that requires limited preparation time and merely nine optodes. Eighteen healthy participants performed two mental imagery tasks, mental drawing and spatial navigation, to answer yes/no questions during one of two auditorily cued time windows. Each of the six questions was answered five times, resulting in five trials per answer. This communication paradigm thus combines both spatial (two different mental imagery tasks, here mental drawing for “yes” and spatial navigation for “no”) and temporal (distinct time windows for encoding a “yes” and “no” answer) fNIRS signal features for information encoding. Participants’ answers were decoded in simulated real-time using general linear model analysis. Joint analysis of all five encoding trials resulted in an average accuracy of 66.67 and 58.33% using the oxygenated (HbO) and deoxygenated (HbR) hemoglobin signal respectively. For half of the participants, an accuracy of 83.33% or higher was reached using either the HbO signal or the HbR signal. For four participants, effective communication with 100% accuracy was achieved using either the HbO or HbR signal. An explorative analysis investigated the differentiability of the two mental tasks based solely on spatial fNIRS signal features. Using multivariate pattern analysis (MVPA) group single-trial accuracies of 58.33% (using 20 training trials per task) and 60.56% (using 40 training trials per task) could be obtained. Combining the five trials per run using a majority voting approach heightened these MVPA accuracies to 62.04 and 75%. Additionally, an fNIRS suitability questionnaire capturing participants’ physical features was administered to explore its predictive value for evaluating general data quality. Obtained questionnaire scores correlated significantly (r = -0.499) with the signal-to-noise of the raw light intensities. While more work is needed to further increase decoding accuracy, this study shows the potential of answer encoding using spatiotemporal fNIRS signal features or spatial fNIRS signal features only.
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Affiliation(s)
- Laurien Nagels-Coune
- Department of Cognitive Neuroscience, Maastricht University, Maastricht, Netherlands.,Maastricht Brain Imaging Center, Maastricht, Netherlands.,University Psychiatric Centre Sint-Kamillus, Bierbeek, Belgium
| | - Amaia Benitez-Andonegui
- Department of Cognitive Neuroscience, Maastricht University, Maastricht, Netherlands.,Maastricht Brain Imaging Center, Maastricht, Netherlands
| | - Niels Reuter
- Institute of Systems Neuroscience, Heinrich-Heine University, Düsseldorf, Germany.,Institute of Neuroscience and Medicine (INM-7), Research Centre Jülich, Jülich, Germany
| | | | - Rainer Goebel
- Department of Cognitive Neuroscience, Maastricht University, Maastricht, Netherlands.,Maastricht Brain Imaging Center, Maastricht, Netherlands.,Brain Innovation B.V., Maastricht, Netherlands
| | - Peter De Weerd
- Department of Cognitive Neuroscience, Maastricht University, Maastricht, Netherlands.,Maastricht Brain Imaging Center, Maastricht, Netherlands.,Maastricht Centre for Systems Biology (MaCSBio), Maastricht University, Maastricht, Netherlands
| | - Lars Riecke
- Department of Cognitive Neuroscience, Maastricht University, Maastricht, Netherlands.,Maastricht Brain Imaging Center, Maastricht, Netherlands
| | - Bettina Sorger
- Department of Cognitive Neuroscience, Maastricht University, Maastricht, Netherlands.,Maastricht Brain Imaging Center, Maastricht, Netherlands
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Kontojannis V, Hostettler I, Brogan RJ, Raza M, Harper-Payne A, Kareem H, Boutelle M, Wilson M. Detection of intracranial hematomas in the emergency department using near infrared spectroscopy. Brain Inj 2019; 33:875-883. [PMID: 31284787 DOI: 10.1080/02699052.2019.1610796] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Hypothesis: Traumatic brain injury (TBI) is one of the most important causes of morbidity and mortality in our society. The development of near infrared technology for the detection of intracranial hematomas may assist earlier diagnosis of TBI. This in turn may enable earlier targeted treatments minimizing the harm and subsequent social and economic effects of TBI. Methods: A handheld, noninvasive Near Infrared Spectroscopy device, Infrascanner 2000, (Infrascan Inc., Philadelphia, PA, USA) was used in a major trauma center to screen for traumatic intracranial hematomas. The Infrascanner was used successfully in 205 patients on their arrival in the emergency department prior to CT head. Results: In the whole cohort, sensitivity was 75%, specificity was 50.43%, with negative predictive value 72.84%, and positive predictive value 53.23%. In 45 patients, where the volume of blood was >3.5mL, the sensitivity was 89.36%, specificity 48.73% with negative predictive value 93.9% and positive predictive value 34.15%. Conclusions: The Infrascanner has a relatively high specificity and negative predictive value; therefore, it could in association with the Neurological examination, help in the triage of the trauma patient with potential brain injury. Further investigation is necessary to determine the use of Infrascanner 2000 as a diagnostic method in TBI.
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Affiliation(s)
| | - Isabel Hostettler
- b Neurosurgery , Imperial College Healthcare NHS Trust , London , UK
| | - Robert James Brogan
- c Imperial College Healthcare NHS Trust, Imperial Neurotrauma Centre, Major Trauma Centre , St Marys Hospital , London , UK
| | - Muhammad Raza
- b Neurosurgery , Imperial College Healthcare NHS Trust , London , UK
| | - Abby Harper-Payne
- d Major Trauma Centre, St Mary's Hospital , Imperial College Healthcare NHS Trust , London , UK
| | - Haider Kareem
- b Neurosurgery , Imperial College Healthcare NHS Trust , London , UK
| | | | - Mark Wilson
- b Neurosurgery , Imperial College Healthcare NHS Trust , London , UK
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Liao J, Li T, Dong W, Wang J, Tian J, Liu J, Quan W, Yan J. Reduced prefrontal-temporal cortical activation during verbal fluency task in obsessive-compulsive disorder: A multi-channel near-infrared spectroscopy study. J Psychiatr Res 2019; 109:33-40. [PMID: 30468975 DOI: 10.1016/j.jpsychires.2018.11.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 11/03/2018] [Accepted: 11/03/2018] [Indexed: 01/26/2023]
Abstract
Functional neuroimaging studies by near-infrared spectroscopy (NIRS) have focused on the role of the prefrontal cortex (PFC) in the pathophysiology of obsessive-compulsive disorder (OCD). However, the reported areas in the PFC were inconsistent in OCD, and correlations between hemodynamic response and clinical symptoms have not been investigated. This study aimed to evaluate the hemodynamic response related to the verbal fluency task (VFT) and assess the relationship between activation and clinical status in OCD patients using a 52-channel NIRS with a wide coverage over the prefrontal and temporal cortices. Seventy patients with OCD and 70 age-, gender- and education level-matched healthy control subjects were examined by NIRS. The relative concentration changes of oxygenated hemoglobin ([oxy-Hb]) were measured. The Yale-Brown obsessive-compulsive scale (Y-BOCS) was used to evaluate the severity of OCD symptoms. Compared to healthy controls group, OCD patients showed smaller [oxy-Hb] changes in most areas of the prefrontal and temporal cortex, including the bilateral orbitofrontal cortex (OFC), right dorsolateral prefrontal cortex (DLPFC), bilateral inferior prefrontal cortex (IPFC), bilateral frontopolar cortex (FPC), left superior temporal gyrus (STG), and bilateral middle temporal gyrus (MTG). Furthermore, the [oxy-Hb] changes in the right FPC were negatively correlated with the Y-BOCS obsessions score and Y-BOCS total score, and the [oxy-Hb] changes in the left OFC were negatively correlated with the Y-BOCS compulsions score. These results suggest that patients with OCD have reduced prefrontal-temporal cortex hemodynamic responses, and that the abnormalities of brain activation were associated with the severity of OCD symptoms.
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Affiliation(s)
- Jinmin Liao
- Inpatient Unit, Peking University Sixth Hospital, Peking University Institute of Mental Health, Key Laboratory of Mental Health, NHC (Peking University), National Clinical Research Center for Mental Disorders (Peking University Sixth Hospital), Beijing 100191, China
| | - Tian Li
- Inpatient Unit, Peking University Sixth Hospital, Peking University Institute of Mental Health, Key Laboratory of Mental Health, NHC (Peking University), National Clinical Research Center for Mental Disorders (Peking University Sixth Hospital), Beijing 100191, China
| | - Wentian Dong
- Department of Translational Medicine, Peking University Sixth Hospital, Peking University Institute of Mental Health, Key Laboratory of Mental Health, NHC (Peking University), National Clinical Research Center for Mental Disorders (Peking University Sixth Hospital), Beijing 100191, China
| | - Jiuju Wang
- Department of Translational Medicine, Peking University Sixth Hospital, Peking University Institute of Mental Health, Key Laboratory of Mental Health, NHC (Peking University), National Clinical Research Center for Mental Disorders (Peking University Sixth Hospital), Beijing 100191, China
| | - Ju Tian
- Department of Translational Medicine, Peking University Sixth Hospital, Peking University Institute of Mental Health, Key Laboratory of Mental Health, NHC (Peking University), National Clinical Research Center for Mental Disorders (Peking University Sixth Hospital), Beijing 100191, China
| | - Jin Liu
- Department of Translational Medicine, Peking University Sixth Hospital, Peking University Institute of Mental Health, Key Laboratory of Mental Health, NHC (Peking University), National Clinical Research Center for Mental Disorders (Peking University Sixth Hospital), Beijing 100191, China
| | - Wenxiang Quan
- Department of Translational Medicine, Peking University Sixth Hospital, Peking University Institute of Mental Health, Key Laboratory of Mental Health, NHC (Peking University), National Clinical Research Center for Mental Disorders (Peking University Sixth Hospital), Beijing 100191, China.
| | - Jun Yan
- Inpatient Unit, Peking University Sixth Hospital, Peking University Institute of Mental Health, Key Laboratory of Mental Health, NHC (Peking University), National Clinical Research Center for Mental Disorders (Peking University Sixth Hospital), Beijing 100191, China.
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Brain activity in response to the touch of a hand on the center of the back. PLoS One 2018; 13:e0206451. [PMID: 30372462 PMCID: PMC6205618 DOI: 10.1371/journal.pone.0206451] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 10/12/2018] [Indexed: 11/19/2022] Open
Abstract
The aim of this study was to validate the possibility of using functional Near-Infrared Spectroscopy (fNIRS) to measure changes in cerebral blood flow in response to a hand being placed on a participant's back, and to identify the areas of enhanced activity in the brain. Nineteen female adult volunteers participated in the study. An experienced school nurse touched the center of the participant's back between the shoulder blades with the palm of her hand. Cerebral blood volume dynamics were measured with a 52-channel fNIRS system. Significantly higher oxygenated hemoglobin (oxy-Hb) concentration levels were recorded by channels 11, 14, 21, 22, 24, 32, 35, 45, 46, and 49 during the touching period than during the resting period. These channels indicated enhanced activity in the supramarginal gyrus, the middle frontal gyrus, the superior temporal gyrus, and the inferior frontal gyrus. The ability to detect changes in cerebral blood flow using this method indicates the possibility of measuring changes in cerebral blood flow using fNIRS when a person is touched on the back. fNIRS has been shown to be useful for studying the effects of touch.
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10
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Ueda S, Ota T, Iida J, Yamamuro K, Yoshino H, Kishimoto N, Kishimoto T. Reduced prefrontal hemodynamic response in adult attention-deficit hyperactivity disorder as measured by near-infrared spectroscopy. Psychiatry Clin Neurosci 2018; 72:380-390. [PMID: 29405508 DOI: 10.1111/pcn.12643] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 12/26/2017] [Accepted: 01/30/2018] [Indexed: 11/30/2022]
Abstract
AIM Recent developments in near-infrared spectroscopy (NIRS) have enabled non-invasive clarification of brain functions in psychiatric disorders. In pediatric attention-deficit hyperactivity disorder (ADHD), reduced prefrontal hemodynamic responses have been observed with NIRS repeatedly. However, there are few studies of adult ADHD by multi-channel NIRS. Therefore, in this study, we used multi-channel NIRS to examine the characteristics of prefrontal hemodynamic responses during the Stroop Color-Word Task (SCWT) in adult ADHD patients and in age- and sex-matched control subjects. METHODS Twelve treatment-naïve adults with ADHD and 12 age- and sex-matched healthy control subjects participated in the present study after giving consent. We used 24-channel NIRS to measure the oxygenated hemoglobin (oxy-Hb) changes at the frontal lobes of participants during the SCWT. We compared the oxy-Hb changes between adults with ADHD and control subjects by t-tests with Bonferroni correction. RESULTS During the SCWT, the oxy-Hb changes observed in the ADHD group were significantly smaller than those in the control group in channels 11, 16, 18, 21, 22, 23, and 24, corresponding to the prefrontal cortex. At channels 16, 21, 23, and 24 of the ADHD group, there were negative correlations between the symptomatic severity and the oxy-Hb changes. CONCLUSION The present study suggests that adults with ADHD have reduced prefrontal hemodynamic response as measured by NIRS.
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Affiliation(s)
- Shotaro Ueda
- Department of Psychiatry, Nara Medical University, Kashihara, Japan
| | - Toyosaku Ota
- Department of Psychiatry, Nara Medical University, Kashihara, Japan
| | - Junzo Iida
- Faculty of Nursing, Nara Medical University, Kashihara, Japan
| | | | - Hiroki Yoshino
- Department of Psychiatry, Nara Medical University, Kashihara, Japan
| | - Naoko Kishimoto
- Department of Psychiatry, Nara Medical University, Kashihara, Japan
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Funane T, Numata T, Sato H, Hiraizumi S, Hasegawa Y, Kuwabara H, Hasegawa K, Kiguchi M. Rearrangeable and exchangeable optical module with system-on-chip for wearable functional near-infrared spectroscopy system. NEUROPHOTONICS 2018; 5:011007. [PMID: 28924567 PMCID: PMC5591581 DOI: 10.1117/1.nph.5.1.011007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Accepted: 08/14/2017] [Indexed: 05/04/2023]
Abstract
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. By supplying [Formula: see text] of power and base and data clocks, the LED module emits both 730- and 855-nm wavelengths of light, amplitudes of which are modulated in each lock-in frequency generated from the base clock, and the APD module provides the lock-in detected signals synchronizing with the data clock. The SoC provided many functions, including automatic-power-control of the LED, automatic judgment of detected power level, and automatic-gain-control of the programmable gain amplifier. The number and the arrangement of modules can be adaptively changed by connecting this exchangeable modules in a daisy chain and setting the parameters dependent on the probing position. Therefore, users can configure a variety of arrangements (single- or multidistance combinations) of them with this module-based system.
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Affiliation(s)
- Tsukasa Funane
- Hitachi, Ltd., Research & Development Group, Center for Exploratory Research, Hatoyama, Saitama, Japan
- Address all correspondence to: Tsukasa Funane, E-mail:
| | - Takashi Numata
- Hitachi, Ltd., Research & Development Group, Center for Exploratory Research, Hatoyama, Saitama, Japan
| | - Hiroki Sato
- Hitachi, Ltd., Research & Development Group, Center for Exploratory Research, Hatoyama, Saitama, Japan
| | | | | | | | | | - Masashi Kiguchi
- Hitachi, Ltd., Research & Development Group, Center for Exploratory Research, Hatoyama, Saitama, Japan
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12
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Siegmund B, Mischok A, Benduhn J, Zeika O, Ullbrich S, Nehm F, Böhm M, Spoltore D, Fröb H, Körner C, Leo K, Vandewal K. Organic narrowband near-infrared photodetectors based on intermolecular charge-transfer absorption. Nat Commun 2017; 8:15421. [PMID: 28580934 PMCID: PMC5465315 DOI: 10.1038/ncomms15421] [Citation(s) in RCA: 75] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Accepted: 03/29/2017] [Indexed: 02/08/2023] Open
Abstract
Blending organic electron donors and acceptors yields intermolecular charge-transfer states with additional optical transitions below their optical gaps. In organic photovoltaic devices, such states play a crucial role and limit the operating voltage. Due to its extremely weak nature, direct intermolecular charge-transfer absorption often remains undetected and unused for photocurrent generation. Here, we use an optical microcavity to increase the typically negligible external quantum efficiency in the spectral region of charge-transfer absorption by more than 40 times, yielding values over 20%. We demonstrate narrowband detection with spectral widths down to 36 nm and resonance wavelengths between 810 and 1,550 nm, far below the optical gap of both donor and acceptor. The broad spectral tunability via a simple variation of the cavity thickness makes this innovative, flexible and potentially visibly transparent device principle highly suitable for integrated low-cost spectroscopic near-infrared photodetection. Interfaces of organic donor-acceptor blends provide intermolecular charge-transfer states with red-shifted but weak absorption. By introducing an optical micro-cavity; Siegmund et al., enhance their photoresponse to achieve narrowband NIR photodetection with broad spectral tunability.
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Affiliation(s)
- Bernhard Siegmund
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP), Technische Universität Dresden, George-Bähr-Straße 1, Dresden 01062, Germany.,Institute for Applied Physics, Technische Universität Dresden, George-Bähr-Straße 1, Dresden 01062, Germany
| | - Andreas Mischok
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP), Technische Universität Dresden, George-Bähr-Straße 1, Dresden 01062, Germany.,Institute for Applied Physics, Technische Universität Dresden, George-Bähr-Straße 1, Dresden 01062, Germany
| | - Johannes Benduhn
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP), Technische Universität Dresden, George-Bähr-Straße 1, Dresden 01062, Germany.,Institute for Applied Physics, Technische Universität Dresden, George-Bähr-Straße 1, Dresden 01062, Germany
| | - Olaf Zeika
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP), Technische Universität Dresden, George-Bähr-Straße 1, Dresden 01062, Germany.,Institute for Applied Physics, Technische Universität Dresden, George-Bähr-Straße 1, Dresden 01062, Germany
| | - Sascha Ullbrich
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP), Technische Universität Dresden, George-Bähr-Straße 1, Dresden 01062, Germany.,Institute for Applied Physics, Technische Universität Dresden, George-Bähr-Straße 1, Dresden 01062, Germany
| | - Frederik Nehm
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP), Technische Universität Dresden, George-Bähr-Straße 1, Dresden 01062, Germany.,Institute for Applied Physics, Technische Universität Dresden, George-Bähr-Straße 1, Dresden 01062, Germany
| | - Matthias Böhm
- Institute for Applied Physics, Technische Universität Dresden, George-Bähr-Straße 1, Dresden 01062, Germany
| | - Donato Spoltore
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP), Technische Universität Dresden, George-Bähr-Straße 1, Dresden 01062, Germany.,Institute for Applied Physics, Technische Universität Dresden, George-Bähr-Straße 1, Dresden 01062, Germany
| | - Hartmut Fröb
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP), Technische Universität Dresden, George-Bähr-Straße 1, Dresden 01062, Germany.,Institute for Applied Physics, Technische Universität Dresden, George-Bähr-Straße 1, Dresden 01062, Germany
| | - Christian Körner
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP), Technische Universität Dresden, George-Bähr-Straße 1, Dresden 01062, Germany.,Institute for Applied Physics, Technische Universität Dresden, George-Bähr-Straße 1, Dresden 01062, Germany
| | - Karl Leo
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP), Technische Universität Dresden, George-Bähr-Straße 1, Dresden 01062, Germany.,Institute for Applied Physics, Technische Universität Dresden, George-Bähr-Straße 1, Dresden 01062, Germany
| | - Koen Vandewal
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP), Technische Universität Dresden, George-Bähr-Straße 1, Dresden 01062, Germany.,Institute for Applied Physics, Technische Universität Dresden, George-Bähr-Straße 1, Dresden 01062, Germany
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13
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Conti C, Botteon A, Colombo C, Realini M, Matousek P. Fluorescence suppression using micro-scale spatially offset Raman spectroscopy. Analyst 2016; 141:5374-81. [DOI: 10.1039/c6an00852f] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We present a new concept of fluorescence suppression in Raman microscopy based on micro-spatially offset Raman spectroscopy which is applicable to thin stratified turbid (diffusely scattering) matrices permitting the retrieval of the Raman signals of sublayers below intensely fluorescing turbid over-layers.
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Affiliation(s)
- Claudia Conti
- Consiglio Nazionale delle Ricerche
- Istituto per la Conservazione e la Valorizzazione dei Beni Culturali (ICVBC)
- Milano
- Italy
| | - Alessandra Botteon
- Consiglio Nazionale delle Ricerche
- Istituto per la Conservazione e la Valorizzazione dei Beni Culturali (ICVBC)
- Milano
- Italy
| | - Chiara Colombo
- Consiglio Nazionale delle Ricerche
- Istituto per la Conservazione e la Valorizzazione dei Beni Culturali (ICVBC)
- Milano
- Italy
| | - Marco Realini
- Consiglio Nazionale delle Ricerche
- Istituto per la Conservazione e la Valorizzazione dei Beni Culturali (ICVBC)
- Milano
- Italy
| | - Pavel Matousek
- Central Laser Facility
- Research Complex at Harwell
- STFC Rutherford Appleton Laboratory
- Harwell Oxford
- UK
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14
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Matousek P, Conti C, Realini M, Colombo C. Micro-scale spatially offset Raman spectroscopy for non-invasive subsurface analysis of turbid materials. Analyst 2015; 141:731-9. [PMID: 26646435 DOI: 10.1039/c5an02129d] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
This article reviews a very recent field of noninvasive analysis of turbid media using micro-scale Spatially Offset Raman Spectroscopy - micro-SORS. The technique combines conventional SORS with microscopy concepts and represents a new imaging modality in Raman microscopy. Micro-SORS facilitates analytical capability for investigating non-destructively the chemical composition of subsurface, micrometer-scale-thick diffusely scattering layers at depths more than an order of magnitude larger than those accessible with the depth resolving power of conventional confocal Raman microscopy. Potential application areas include nondestructive subsurface analysis of painted layers in cultural heritage, characterization of stratified polymer systems, analysis of layered biological samples or forensic analysis. The article discusses the basic principles of the technique, its variants and outlines emerging applications in this rapidly evolving field.
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Affiliation(s)
- P Matousek
- Central Laser Facility, Research Complex at Harwell, STFC Rutherford Appleton Laboratory, Harwell, Oxford, OX11 0QX, UK.
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15
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Heilbronner U, Hinrichs H, Heinze HJ, Zaehle T. Caffeine differentially alters cortical hemodynamic activity during working memory: a near infrared spectroscopy study. BMC Res Notes 2015; 8:520. [PMID: 26427367 PMCID: PMC4590696 DOI: 10.1186/s13104-015-1491-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Accepted: 09/21/2015] [Indexed: 11/10/2022] Open
Abstract
Background Caffeine is a widely used stimulant with potentially beneficial effects on cognition as well as vasoconstrictive properties. In functional magnetic imaging research, caffeine has gained attention as a potential enhancer of the blood oxygenation level-dependent (BOLD) response. In order to clarify changes of oxy- and deoxyhemoglobin (HbO and HbR) induced by caffeine during a cognitive task, we investigated a working memory (WM) paradigm (visual 2-back) using near-infrared spectroscopy (NIRS). Results Behaviorally, caffeine had no effect on the WM performance but influenced reaction times in the 0-back condition. NIRS data demonstrate caffeine-dependent alterations of the course of the hemodynamic response. The intake of 200 mg caffeine caused a significant decrease of the HbO response between 20 and 40 s after the onset of a 2-back task in the bilateral inferior frontal cortex (IFC). In parallel, the HbR response of the left IFC was significantly increased due to caffeine intake. Conclusions In line with previous results, we did not detect an effect of caffeine on most aspects of behavior. Effects of caffeine on brain vasculature were detected as general reduction of HbO. Neuronal effects of caffeine are reflected in an increased concentration of HbR in the left hemisphere when performing a verbal memory task and suggest influences on metabolism.
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Affiliation(s)
- Urs Heilbronner
- DZNE, German Center for Neurodegenerative Diseases, Otto-von-Guericke University, Magdeburg, Germany. .,Institute of Psychiatric Phenomics and Genomics, Ludwig-Maximilians-University, Munich, Germany.
| | - Hermann Hinrichs
- DZNE, German Center for Neurodegenerative Diseases, Otto-von-Guericke University, Magdeburg, Germany. .,LIN, Leibniz Institute for Neurobiology, Magdeburg, Germany. .,Department of Neurology, Otto-von-Guericke University, Magdeburg, Germany.
| | - Hans-Jochen Heinze
- DZNE, German Center for Neurodegenerative Diseases, Otto-von-Guericke University, Magdeburg, Germany. .,LIN, Leibniz Institute for Neurobiology, Magdeburg, Germany. .,Department of Neurology, Otto-von-Guericke University, Magdeburg, Germany.
| | - Tino Zaehle
- DZNE, German Center for Neurodegenerative Diseases, Otto-von-Guericke University, Magdeburg, Germany. .,LIN, Leibniz Institute for Neurobiology, Magdeburg, Germany. .,Department of Neurology, Otto-von-Guericke University, Magdeburg, Germany.
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16
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Funane T. Wearable near-infrared spectroscopy neuroimaging and its applications. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2015; 2015:4025-8. [PMID: 26737177 DOI: 10.1109/embc.2015.7319277] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Wearable near-infrared spectroscopy (NIRS) systems are expected to be applied in various fields such as health care (medical use), education (teaching), and biofeedback. An investigation on hyperscanning by using NIRS is discussed first, where multiple brains were simultaneously measured for investigating and evaluating important social interactions, such as communication. The relationship between interacting brain activities and performance in cooperation has been demonstrated. An investigation on mood-state measurements in a return-to-work program is next discussed. It has been reported that a specified index calculated using NIRS signals obtained during performance of a working memory task correlated with a mood score. Using this index, the mood states of volunteers who participated in a return-to-work program after psychiatric clinical treatment were monitored. It has been suggested that the relationship between brain activities and subjective assessment of depression mood will be useful for evaluating the recovery stage for return-to-work programs. These techniques open new applications of wearable NIRS systems in mental health care.
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17
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Conti C, Realini M, Colombo C, Sowoidnich K, Afseth NK, Bertasa M, Botteon A, Matousek P. Noninvasive Analysis of Thin Turbid Layers Using Microscale Spatially Offset Raman Spectroscopy. Anal Chem 2015; 87:5810-5. [DOI: 10.1021/acs.analchem.5b01080] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Claudia Conti
- Institute for
the Conservation and Valorization of Cultural Heritage (ICVBC), National Research Council, Via Cozzi 53, 20125, Milano, Italy
| | - Marco Realini
- Institute for
the Conservation and Valorization of Cultural Heritage (ICVBC), National Research Council, Via Cozzi 53, 20125, Milano, Italy
| | - Chiara Colombo
- Institute for
the Conservation and Valorization of Cultural Heritage (ICVBC), National Research Council, Via Cozzi 53, 20125, Milano, Italy
| | - Kay Sowoidnich
- Central
Laser Facility, Research Complex
at Harwell, STFC Rutherford Appleton Laboratory,
Harwell Oxford, OX11 0QX, United Kingdom
| | - Nils Kristian Afseth
- Nofima-Norwegian Institute of Food, Fisheries and Aquaculture Research, PB 210, N-1431 Ås, Norway
| | - Moira Bertasa
- Institute for
the Conservation and Valorization of Cultural Heritage (ICVBC), National Research Council, Via Cozzi 53, 20125, Milano, Italy
| | - Alessandra Botteon
- Institute for
the Conservation and Valorization of Cultural Heritage (ICVBC), National Research Council, Via Cozzi 53, 20125, Milano, Italy
| | - Pavel Matousek
- Central
Laser Facility, Research Complex
at Harwell, STFC Rutherford Appleton Laboratory,
Harwell Oxford, OX11 0QX, United Kingdom
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18
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Conti C, Realini M, Colombo C, Matousek P. Comparison of key modalities of micro-scale spatially offset Raman spectroscopy. Analyst 2015; 140:8127-33. [DOI: 10.1039/c5an01900a] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We compare several basic embodiments of a recently proposed and demonstrated micrometer-scale Spatially Offset Raman Spectroscopy (micro-SORS).
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Affiliation(s)
- C. Conti
- Consiglio Nazionale delle Ricerche
- Istituto per la Conservazione e la Valorizzazione dei Beni Culturali (ICVBC)
- Milano
- Italy
| | - M. Realini
- Consiglio Nazionale delle Ricerche
- Istituto per la Conservazione e la Valorizzazione dei Beni Culturali (ICVBC)
- Milano
- Italy
| | - C. Colombo
- Consiglio Nazionale delle Ricerche
- Istituto per la Conservazione e la Valorizzazione dei Beni Culturali (ICVBC)
- Milano
- Italy
| | - P. Matousek
- Central Laser Facility
- Research Complex at Harwell
- STFC Rutherford Appleton Laboratory
- Harwell Oxford
- UK
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19
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Funane T, Sato H, Yahata N, Takizawa R, Nishimura Y, Kinoshita A, Katura T, Atsumori H, Fukuda M, Kasai K, Koizumi H, Kiguchi M. Concurrent fNIRS-fMRI measurement to validate a method for separating deep and shallow fNIRS signals by using multidistance optodes. NEUROPHOTONICS 2015; 2:015003. [PMID: 26157983 PMCID: PMC4478864 DOI: 10.1117/1.nph.2.1.015003] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2014] [Accepted: 01/05/2015] [Indexed: 05/12/2023]
Abstract
It has been reported that a functional near-infrared spectroscopy (fNIRS) signal can be contaminated by extracerebral contributions. Many algorithms using multidistance separations to address this issue have been proposed, but their spatial separation performance has rarely been validated with simultaneous measurements of fNIRS and functional magnetic resonance imaging (fMRI). We previously proposed a method for discriminating between deep and shallow contributions in fNIRS signals, referred to as the multidistance independent component analysis (MD-ICA) method. In this study, to validate the MD-ICA method from the spatial aspect, multidistance fNIRS, fMRI, and laser-Doppler-flowmetry signals were simultaneously obtained for 12 healthy adult males during three tasks. The fNIRS signal was separated into deep and shallow signals by using the MD-ICA method, and the correlation between the waveforms of the separated fNIRS signals and the gray matter blood oxygenation level-dependent signals was analyzed. A three-way analysis of variance ([Formula: see text]) indicated that the main effect of fNIRS signal depth on the correlation is significant [[Formula: see text], [Formula: see text]]. This result indicates that the MD-ICA method successfully separates fNIRS signals into spatially deep and shallow signals, and the accuracy and reliability of the fNIRS signal will be improved with the method.
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Affiliation(s)
- Tsukasa Funane
- Hitachi, Ltd., Central Research Laboratory, Hatoyama, Saitama 350-0395, Japan
- Address all correspondence to: Tsukasa Funane, E-mail:
| | - Hiroki Sato
- Hitachi, Ltd., Central Research Laboratory, Hatoyama, Saitama 350-0395, Japan
| | - Noriaki Yahata
- The University of Tokyo, Graduate School of Medicine, Department of Youth Mental Health, Bunkyo-ku, Tokyo 113-8655, Japan
| | - Ryu Takizawa
- The University of Tokyo, Graduate School of Medicine, Department of Neuropsychiatry, Bunkyo-ku, Tokyo 113-8655, Japan
- King’s College London, Institute of Psychiatry, MRC Social, Genetic and Developmental Psychiatry Centre, London, SE5 8AF, United Kingdom
| | - Yukika Nishimura
- The University of Tokyo, Graduate School of Medicine, Department of Neuropsychiatry, Bunkyo-ku, Tokyo 113-8655, Japan
| | - Akihide Kinoshita
- The University of Tokyo, Graduate School of Medicine, Department of Neuropsychiatry, Bunkyo-ku, Tokyo 113-8655, Japan
| | - Takusige Katura
- Hitachi, Ltd., Central Research Laboratory, Hatoyama, Saitama 350-0395, Japan
| | - Hirokazu Atsumori
- Hitachi, Ltd., Central Research Laboratory, Hatoyama, Saitama 350-0395, Japan
| | - Masato Fukuda
- Gunma University Graduate School of Medicine, Department of Psychiatry and Neuroscience, Maebashi, Gunma 371-8511, Japan
| | - Kiyoto Kasai
- The University of Tokyo, Graduate School of Medicine, Department of Neuropsychiatry, Bunkyo-ku, Tokyo 113-8655, Japan
| | - Hideaki Koizumi
- Hitachi, Ltd., Central Research Laboratory, Hatoyama, Saitama 350-0395, Japan
| | - Masashi Kiguchi
- Hitachi, Ltd., Central Research Laboratory, Hatoyama, Saitama 350-0395, Japan
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20
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Inamoto K, Sakuma S, Ariji Y, Higuchi N, Izumi M, Nakata K. Measurement of cerebral blood volume dynamics during volitional swallowing using functional near-infrared spectroscopy: an exploratory study. Neurosci Lett 2014; 588:67-71. [PMID: 25545557 DOI: 10.1016/j.neulet.2014.12.034] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2014] [Revised: 12/04/2014] [Accepted: 12/16/2014] [Indexed: 10/24/2022]
Abstract
The aim of this study was to examine cerebral blood volume dynamics during volitional swallowing using multi-channel functional near-infrared spectroscopy (fNIRS) to understand the basic cortical activation patterns. Fifteen volunteers (age, 26.5±1.3 years, mean±SD) performed volitional swallowing of a 5-ml bolus of water as a task. A 52-channel fNIRS system was used for measuring oxy-Hb levels. We determined the oxy-Hb concentration changes in each channel by calculating the differences between rest and task oxy-Hb levels. Differences in rest and task data were assessed using a paired-t test (p<0.05). A significant increase in oxy-Hb was found in 21 channels. The cortical regions that exhibited increased oxy-Hb concentration included the bilateral precentral gyrus, postcentral gyrus, inferior frontal gyrus, superior temporal gyrus, middle temporal gyrus, and supramarginal gyrus. These data provide a description of cortical activation patterns during volitional swallowing using fNIRS, which will be useful for the evaluation of dysphasia and the effects of the rehabilitation [Corrected].
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Affiliation(s)
- Kyoko Inamoto
- Department of Endodontics, School of Dentistry, Aichi Gakuin University, Aichi, Japan.
| | - Shigemitsu Sakuma
- Department of Fixed Prosthodontics, School of Dentistry, Aichi Gakuin University, Aichi, Japan
| | - Yoshiko Ariji
- Department of Oral and Maxillofacial Radiology, School of Dentistry, Aichi Gakuin University, Aichi, Japan
| | - Naoya Higuchi
- Department of Endodontics, School of Dentistry, Aichi Gakuin University, Aichi, Japan
| | - Masahiro Izumi
- Department of Oral and Maxillofacial Radiology, School of Dentistry, Aichi Gakuin University, Aichi, Japan
| | - Kazuhiko Nakata
- Department of Endodontics, School of Dentistry, Aichi Gakuin University, Aichi, Japan
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21
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Near-Infrared Spectroscopy during the Verbal Fluency Task before and after Treatment with Image Exposure and SSRI Therapy in Patients with Obsessive-Compulsive Disorder. Case Rep Psychiatry 2014; 2014:591023. [PMID: 25317351 PMCID: PMC4182012 DOI: 10.1155/2014/591023] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Revised: 08/22/2014] [Accepted: 08/25/2014] [Indexed: 11/21/2022] Open
Abstract
Drug therapy with selective serotonin reuptake inhibitors (SSRIs) has been used as a treatment for obsessive-compulsive disorder (OCD). In the present case report, exposure therapy was used in addition to escitalopram (20 mg) to treat a 28-year-old female patient with OCD for 6 months. Her obsessive-compulsive symptoms comprised thoughts of words such as rape, crematorium, neck hanging, unhappy, death, die, and kill and images such as a shelf of gods, a shrine, a Buddhist altar, the sun, the sky, and the faces of her parents, siblings, and relatives. As exposure therapy, she was asked to view the images associated with these symptoms three times a day along with drug therapy. With the combination of drug and exposure therapies, her obsessive-compulsive symptoms improved within 6 months, with no interference in her daily life. Multichannel near-infrared spectroscopy (NIRS) showed improvement of brain function in the temporal and frontal lobes after treatment. These results suggest that NIRS can be used as an indicator of brain function improvement in patients with OCD.
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22
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Near-infrared spectroscopic study of frontopolar activation during face-to-face conversation in major depressive disorder and bipolar disorder. J Psychiatr Res 2014; 57:74-83. [PMID: 25056175 DOI: 10.1016/j.jpsychires.2014.06.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2014] [Revised: 06/11/2014] [Accepted: 06/18/2014] [Indexed: 11/22/2022]
Abstract
Major depressive disorder (MDD) and bipolar disorder (BD) patients show speech characteristics that vary greatly according to mood state. In a previous study, we found impaired temporal and right inferior frontal gyrus (IFG) activation in schizophrenia during face-to-face conversation; no study had, however, previously investigated mood disorders during face-to-face conversation. Here, we investigated frontal and temporal lobe activation during conversation in patients with MDD and BD. Frontal and temporal lobe activation was measured using near-infrared spectroscopy (NIRS) in 29 patients with MDD, 31 patients with BD, and 31 normal controls (NC). We compared continuous activation and rapid change of activation with talk/listen phase changes during the conversation and analyzed the correlation between these indices and clinical variables. Both the MDD and BD groups showed decreased continuous activation in the left dorsolateral prefrontal (DLPFC) and left frontopolar cortices (FPCs); they also showed decreased rapid change in bilateral FPC activation. In the MDD group, the rapid change of activation was positively correlated with Global Assessment of Functioning (GAF) scores. In the BD group, continuous activation was negatively correlated with age of onset. These results indicate that frontal activation during conversation decreases in both MDD and BD. However, both continuous activation and rapid change may reflect the pathophysiological character of MDD and BD; in particular, the reduced amount of rapid change in the right FPC may be related to impaired adaptive ability in MDD.
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23
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Funane T, Homae F, Watanabe H, Kiguchi M, Taga G. Greater contribution of cerebral than extracerebral hemodynamics to near-infrared spectroscopy signals for functional activation and resting-state connectivity in infants. NEUROPHOTONICS 2014; 1:025003. [PMID: 26157977 PMCID: PMC4478757 DOI: 10.1117/1.nph.1.2.025003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2014] [Revised: 07/15/2014] [Accepted: 07/25/2014] [Indexed: 05/12/2023]
Abstract
While near-infrared spectroscopy (NIRS) has been increasingly applied to neuroimaging and functional connectivity studies in infants, it has not been quantitatively examined as to what extent the deep tissue (such as cerebral tissue) as opposed to shallow tissue (such as scalp), contributes to NIRS signals measured in infants. A method for separating the effects of deep- and shallow-tissue layers was applied to data of nine sleeping three-month-old infants who had been exposed to 3-s speech sounds or silence (i.e., resting state) and whose hemodynamic changes over their bilateral temporal cortices had been measured by using an NIRS system with multiple source-detector (S-D) distances. The deep-layer contribution was found to be large during resting [67% at S-D 20 mm, 78% at S-D 30 mm for oxygenated hemoglobin (oxy-Hb)] as well as during the speech condition (72% at S-D 20 mm, 82% at S-D 30 mm for oxy-Hb). A left-right connectivity analysis showed that correlation coefficients between left and right channels did not differ between original- and deep-layer signals under no-stimulus conditions and that of original- and deep-layer signals were larger than those of the shallow layer. These results suggest that NIRS signals obtained in infants with appropriate S-D distances largely reflected cerebral hemodynamic changes.
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Affiliation(s)
- Tsukasa Funane
- Hitachi, Ltd., Central Research Laboratory, 2520 Akanuma, Hatoyama, Saitama 350–0395, Japan
| | - Fumitaka Homae
- Tokyo Metropolitan University, Department of Language Sciences, 1-1 Minami Osawa, Hachioji, Tokyo 192-0397, Japan
| | - Hama Watanabe
- The University of Tokyo, Graduate School of Education, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Masashi Kiguchi
- Hitachi, Ltd., Central Research Laboratory, 2520 Akanuma, Hatoyama, Saitama 350–0395, Japan
| | - Gentaro Taga
- The University of Tokyo, Graduate School of Education, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
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Schudlo LC, Chau T. Dynamic topographical pattern classification of multichannel prefrontal NIRS signals: II. Online differentiation of mental arithmetic and rest. J Neural Eng 2013; 11:016003. [PMID: 24311057 DOI: 10.1088/1741-2560/11/1/016003] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVE Near-infrared spectroscopy (NIRS) has recently gained attention as a modality for brain-computer interfaces (BCIs), which may serve as an alternative access pathway for individuals with severe motor impairments. For NIRS-BCIs to be used as a real communication pathway, reliable online operation must be achieved. Yet, only a limited number of studies have been conducted online to date. These few studies were carried out under a synchronous paradigm and did not accommodate an unconstrained resting state, precluding their practical clinical implication. Furthermore, the potentially discriminative power of spatiotemporal characteristics of activation has yet to be considered in an online NIRS system. APPROACH In this study, we developed and evaluated an online system-paced NIRS-BCI which was driven by a mental arithmetic activation task and accommodated an unconstrained rest state. With a dual-wavelength, frequency domain near-infrared spectrometer, measurements were acquired over nine sites of the prefrontal cortex, while ten able-bodied participants selected letters from an on-screen scanning keyboard via intentionally controlled brain activity (using mental arithmetic). Participants were provided dynamic NIR topograms as continuous visual feedback of their brain activity as well as binary feedback of the BCI's decision (i.e. if the letter was selected or not). To classify the hemodynamic activity, temporal features extracted from the NIRS signals and spatiotemporal features extracted from the dynamic NIR topograms were used in a majority vote combination of multiple linear classifiers. MAIN RESULTS An overall online classification accuracy of 77.4 ± 10.5% was achieved across all participants. The binary feedback was found to be very useful during BCI use, while not all participants found value in the continuous feedback provided. SIGNIFICANCE These results demonstrate that mental arithmetic is a potent mental task for driving an online system-paced NIRS-BCI. BCI feedback that reflects the classifier's decision has the potential to improve user performance. The proposed system can provide a framework for future online NIRS-BCI development and testing.
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Affiliation(s)
- Larissa C Schudlo
- Bloorview Research Institute, Holland Bloorview Kids Rehabilitation Hospital, Toronto, Ontario, Canada. Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada
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25
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Differential spatiotemporal characteristics of the prefrontal hemodynamic response and their association with functional impairment in schizophrenia and major depression. Schizophr Res 2013; 150:459-67. [PMID: 24016725 DOI: 10.1016/j.schres.2013.08.026] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Revised: 08/09/2013] [Accepted: 08/19/2013] [Indexed: 11/22/2022]
Abstract
Recent neuroimaging studies have shown similarities and differences in prefrontal abnormalities between patients with schizophrenia (SZ) and major depressive disorder (MDD). However, the differential spatiotemporal characteristics of these abnormalities and their association with functional impairment remain unclear. To elucidate differential brain pathophysiology in these disorders, we used multichannel near-infrared spectroscopy (NIRS) to measure the spatiotemporal characteristics of prefrontal activation and investigated their association with global functioning levels. The study included 96 individuals: 32 patients with SZ, 32 patients with MDD, and 32 demographically matched healthy subjects. During a verbal fluency task, the changes in oxygenated and deoxygenated hemoglobin ([oxy-Hb] and [deoxy-Hb]) signals over the prefrontal cortex (PFC) were measured using 52-channel NIRS and compared among the 3 groups. Patients with SZ and MDD showed lesser-than-normal [oxy-Hb] activation during the task, whereas the initial slope of [oxy-Hb] activation was steeper for patients with MDD than for patients with SZ. The reduced hemodynamic response was associated with lower global functioning, and the correlative regions were different between the 2 disorders (frontopolar PFC in SZ; dorsolateral and ventrolateral PFC in MDD). The hypofrontality observed in patients with SZ and MDD is consistent with the findings of previous neuroimaging studies. Moreover, the spatiotemporal characteristics and the functional significance of the prefrontal hemodynamic response could differentiate the 2 psychiatric disorders. These results suggest a differential brain pathophysiology between SZ and MDD. Future large-scale studies are needed to determine the practical applicability of these findings for clinical diagnosis and evaluation.
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Okada K, Ota T, Iida J, Kishimoto N, Kishimoto T. Lower prefrontal activity in adults with obsessive-compulsive disorder as measured by near-infrared spectroscopy. Prog Neuropsychopharmacol Biol Psychiatry 2013; 43:7-13. [PMID: 23220093 DOI: 10.1016/j.pnpbp.2012.11.013] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2012] [Revised: 11/05/2012] [Accepted: 11/28/2012] [Indexed: 11/25/2022]
Abstract
Recent developments in near-infrared spectroscopy (NIRS) have enabled the non-invasive elucidation of the neurobiological underpinnings of psychiatric disorders. Functional neuroimaging studies in human patients have suggested that the frontal cortex and subcortical structures may play a role in the pathophysiology of obsessive-compulsive disorder (OCD). Here we used NIRS to investigate neurobiological function in 12 patients with OCD and 12 age- and sex-matched, healthy control subjects. The relative concentrations of oxyhemoglobin (oxy-Hb) were measured with prefrontal probes every 0.1 s, during performance of a Stroop color-word task, using 24-channel NIRS. Oxy-Hb changes in the prefrontal cortex of the OCD group were significantly smaller than those in the control group, especially in the left lateral prefrontal cortex. These results suggest that patients with OCD have reduced prefrontal hemodynamic responses as measured by NIRS.
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Affiliation(s)
- Koji Okada
- Department of Psychiatry, Nara Medical University, Nara 634-8522, Japan.
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27
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Ota T, Iida J, Sawada M, Suehiro Y, Yamamuro K, Matsuura H, Tanaka S, Kishimoto N, Negoro H, Kishimoto T. Reduced prefrontal hemodynamic response in pediatric obsessive-compulsive disorder as measured by near-infrared spectroscopy. Child Psychiatry Hum Dev 2013; 44:265-77. [PMID: 22833309 DOI: 10.1007/s10578-012-0323-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Recent developments in near-infrared spectroscopy (NIRS) have enabled non-invasive clarification of brain functions in psychiatric disorders. Functional neuroimaging studies of patients with obsessive-compulsive disorder (OCD) have suggested that the frontal cortex and subcortical structures may play a role in the pathophysiology of the disorder. Twelve treatment-naïve children with OCD and 12 age- and sex-matched healthy control subjects participated in the present study after giving consent. The relative concentrations of oxyhemoglobin (oxy-Hb) were measured with prefrontal probes every 0.1 s during the Stroop color-word task, using 24-channel NIRS machines. During the Stroop color-word task, the oxy-Hb changes in the OCD group were significantly smaller than those in the control group in the prefrontal cortex, especially in the frontopolar cortex. The present study suggests that children with OCD have reduced prefrontal hemodynamic response as measured by NIRS.
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Affiliation(s)
- Toyosaku Ota
- Department of Psychiatry, Nara Medical University, 840 Shijyou-cho, Kashihara-shi, 634-8522, Nara, Japan.
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28
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Funane T, Atsumori H, Katura T, Obata AN, Sato H, Tanikawa Y, Okada E, Kiguchi M. Quantitative evaluation of deep and shallow tissue layers' contribution to fNIRS signal using multi-distance optodes and independent component analysis. Neuroimage 2013; 85 Pt 1:150-65. [PMID: 23439443 DOI: 10.1016/j.neuroimage.2013.02.026] [Citation(s) in RCA: 118] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Accepted: 02/04/2013] [Indexed: 11/24/2022] Open
Abstract
To quantify the effect of absorption changes in the deep tissue (cerebral) and shallow tissue (scalp, skin) layers on functional near-infrared spectroscopy (fNIRS) signals, a method using multi-distance (MD) optodes and independent component analysis (ICA), referred to as the MD-ICA method, is proposed. In previous studies, when the signal from the shallow tissue layer (shallow signal) needs to be eliminated, it was often assumed that the shallow signal had no correlation with the signal from the deep tissue layer (deep signal). In this study, no relationship between the waveforms of deep and shallow signals is assumed, and instead, it is assumed that both signals are linear combinations of multiple signal sources, which allows the inclusion of a "shared component" (such as systemic signals) that is contained in both layers. The method also assumes that the partial optical path length of the shallow layer does not change, whereas that of the deep layer linearly increases along with the increase of the source-detector (S-D) distance. Deep- and shallow-layer contribution ratios of each independent component (IC) are calculated using the dependence of the weight of each IC on the S-D distance. Reconstruction of deep- and shallow-layer signals are performed by the sum of ICs weighted by the deep and shallow contribution ratio. Experimental validation of the principle of this technique was conducted using a dynamic phantom with two absorbing layers. Results showed that our method is effective for evaluating deep-layer contributions even if there are high correlations between deep and shallow signals. Next, we applied the method to fNIRS signals obtained on a human head with 5-, 15-, and 30-mm S-D distances during a verbal fluency task, a verbal working memory task (prefrontal area), a finger tapping task (motor area), and a tetrametric visual checker-board task (occipital area) and then estimated the deep-layer contribution ratio. To evaluate the signal separation performance of our method, we used the correlation coefficients of a laser-Doppler flowmetry (LDF) signal and a nearest 5-mm S-D distance channel signal with the shallow signal. We demonstrated that the shallow signals have a higher temporal correlation with the LDF signals and with the 5-mm S-D distance channel than the deep signals. These results show the MD-ICA method can discriminate between deep and shallow signals.
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Affiliation(s)
- Tsukasa Funane
- Hitachi, Ltd., Central Research Laboratory, Hatoyama, Saitama 350-0395, Japan.
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29
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Matousek P, Stone N. Recent advances in the development of Raman spectroscopy for deep non-invasive medical diagnosis. JOURNAL OF BIOPHOTONICS 2013; 6:7-19. [PMID: 23129567 DOI: 10.1002/jbio.201200141] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2012] [Revised: 09/13/2012] [Accepted: 09/18/2012] [Indexed: 05/21/2023]
Abstract
Raman spectroscopy has recently undergone major advances in the area of deep non-invasive characterisation of biological tissues. The progress stems from the development of spatially offset Raman spectroscopy (SORS) and renaissance of transmission Raman spectroscopy permitting the assessment of diffusely scattering samples at depths several orders of magnitude deeper than possible with conventional Raman spectroscopy. Examples of emerging applications include non-invasive diagnosis of bone disease, cancer and monitoring of glucose levels. This article reviews this fast moving field focusing on recent developments within the medical area.
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Affiliation(s)
- Pavel Matousek
- Central Laser Facility, Research Complex at Harwell, STFC Rutherford Appleton Laboratory, Harwell Oxford, UK.
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30
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Funane T, Atsumori H, Kiguchi M, Tanikawa Y, Okada E. Dynamic phantom with two stage-driven absorbers for mimicking hemoglobin changes in superficial and deep tissues. JOURNAL OF BIOMEDICAL OPTICS 2012; 17:047001. [PMID: 22559692 DOI: 10.1117/1.jbo.17.4.047001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
In near-infrared spectroscopy (NIRS) for monitoring brain activity and cerebral functional connectivity, the effect of superficial tissue on NIRS signals needs to be considered. Although some methods for determining the effect of scalp and brain have been proposed, direct validation of the methods has been difficult because the actual absorption changes cannot be known. In response to this problem, we developed a dynamic phantom that mimics hemoglobin changes in superficial and deep tissues, thus allowing us to experimentally validate the methods. Two absorber layers are independently driven with two one-axis automatic stages. We can use the phantom to design any type of waveform (e.g., brain activity or systemic fluctuation) of absorption change, which can then be reproducibly measured. To determine the effectiveness of the phantom, we used it for a multiple source-detector distance measurement. We also investigated the performance of a subtraction method with a short-distance regressor. The most accurate lower-layer change was obtained when a shortest-distance channel was used. Furthermore, when an independent component analysis was applied to the same data, the extracted components were in good agreement with the actual signals. These results demonstrate that the proposed phantom can be used for evaluating methods of discriminating the effects of superficial tissue.
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Affiliation(s)
- Tsukasa Funane
- Hitachi Ltd., Central Research Laboratory, Hatoyama, Saitama 350-0395, Japan.
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31
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Ferrari M, Quaresima V. A brief review on the history of human functional near-infrared spectroscopy (fNIRS) development and fields of application. Neuroimage 2012; 63:921-35. [PMID: 22510258 DOI: 10.1016/j.neuroimage.2012.03.049] [Citation(s) in RCA: 1074] [Impact Index Per Article: 89.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2011] [Revised: 02/21/2012] [Accepted: 03/16/2012] [Indexed: 12/14/2022] Open
Abstract
This review is aimed at celebrating the upcoming 20th anniversary of the birth of human functional near-infrared spectroscopy (fNIRS). After the discovery in 1992 that the functional activation of the human cerebral cortex (due to oxygenation and hemodynamic changes) can be explored by NIRS, human functional brain mapping research has gained a new dimension. fNIRS or optical topography, or near-infrared imaging or diffuse optical imaging is used mainly to detect simultaneous changes in optical properties of the human cortex from multiple measurement sites and displays the results in the form of a map or image over a specific area. In order to place current fNIRS research in its proper context, this paper presents a brief historical overview of the events that have shaped the present status of fNIRS. In particular, technological progresses of fNIRS are highlighted (i.e., from single-site to multi-site functional cortical measurements (images)), introduction of the commercial multi-channel systems, recent commercial wireless instrumentation and more advanced prototypes.
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Affiliation(s)
- Marco Ferrari
- Department of Health Sciences, University of L'Aquila, L'Aquila, Italy.
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32
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Tanaka H, Katura T. Classification of change detection and change blindness from near-infrared spectroscopy signals. JOURNAL OF BIOMEDICAL OPTICS 2011; 16:087001. [PMID: 21895328 DOI: 10.1117/1.3606494] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Using a machine-learning classification algorithm applied to near-infrared spectroscopy (NIRS) signals, we classify a success (change detection) or a failure (change blindness) in detecting visual changes for a change-detection task. Five subjects perform a change-detection task, and their brain activities are continuously monitored. A support-vector-machine algorithm is applied to classify the change-detection and change-blindness trials, and correct classification probability of 70-90% is obtained for four subjects. Two types of temporal shapes in classification probabilities are found: one exhibiting a maximum value after the task is completed (postdictive type), and another exhibiting a maximum value during the task (predictive type). As for the postdictive type, the classification probability begins to increase immediately after the task completion and reaches its maximum in about the time scale of neuronal hemodynamic response, reflecting a subjective report of change detection. As for the predictive type, the classification probability shows an increase at the task initiation and is maximal while subjects are performing the task, predicting the task performance in detecting a change. We conclude that decoding change detection and change blindness from NIRS signal is possible and argue some future applications toward brain-machine interfaces.
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Affiliation(s)
- Hirokazu Tanaka
- Hitachi, Ltd., Central Research Laboratory, 2520 Akanuma, Hatoyama, Saitama 350-0395, Japan.
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33
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Funane T, Kiguchi M, Atsumori H, Sato H, Kubota K, Koizumi H. Synchronous activity of two people's prefrontal cortices during a cooperative task measured by simultaneous near-infrared spectroscopy. JOURNAL OF BIOMEDICAL OPTICS 2011; 16:077011. [PMID: 21806291 DOI: 10.1117/1.3602853] [Citation(s) in RCA: 120] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The brain activity during cooperation as a form of social process is studied. We investigate the relationship between coinstantaneous brain-activation signals of multiple participants and their cooperative-task performance. A wearable near-infrared spectroscopy (NIRS) system is used for simultaneously measuring the brain activities of two participants. Each pair of participants perform a cooperative task, and their relative changes in cerebral blood are measured with the NIRS system. As for the task, the participants are told to count 10 s in their mind after an auditory cue and press a button. They are also told to adjust the timing of their button presses to make them as synchronized as possible. Certain information, namely, the "intertime interval" between the two button presses of each participant pair and which of the participants was the faster, is fed back to the participants by a beep sound after each trial. When the spatiotemporal covariance between the activation patterns of the prefrontal cortices of each participant is higher, the intertime interval between their button-press times was shorter. This result suggests that the synchronized activation patterns of the two participants' brains are associated with their performance when they interact in a cooperative task.
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Affiliation(s)
- Tsukasa Funane
- Hitachi, Ltd., Central Research Laboratory, Hatoyama, Saitama 350-0395, Japan.
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34
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Buckley K, Matousek P. Non-invasive analysis of turbid samples using deep Raman spectroscopy. Analyst 2011; 136:3039-50. [DOI: 10.1039/c0an00723d] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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35
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Kuwajima M, Sawaguchi T. Similar prefrontal cortical activities between general fluid intelligence and visuospatial working memory tasks in preschool children as revealed by optical topography. Exp Brain Res 2010; 206:381-97. [DOI: 10.1007/s00221-010-2415-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2009] [Accepted: 09/03/2010] [Indexed: 11/28/2022]
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36
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Atsumori H, Kiguchi M, Katura T, Funane T, Obata A, Sato H, Manaka T, Iwamoto M, Maki A, Koizumi H, Kubota K. Noninvasive imaging of prefrontal activation during attention-demanding tasks performed while walking using a wearable optical topography system. JOURNAL OF BIOMEDICAL OPTICS 2010; 15:046002. [PMID: 20799804 DOI: 10.1117/1.3462996] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Optical topography (OT) based on near-infrared spectroscopy is a noninvasive technique for mapping the relative concentration changes in oxygenated and deoxygenated hemoglobin (oxy- and deoxy-Hb, respectively) in the human cerebral cortex. In our previous study, we developed a small and light wearable optical topography (WOT) system that covers the entire forehead for monitoring prefrontal activation. In the present study, we examine whether the WOT system is applicable to OT measurement while walking, which has been difficult with conventional OT systems. We conduct OT measurements while subjects perform an attention-demanding (AD) task of balancing a ping-pong ball on a small card while walking. The measured time course and power spectra of the relative concentration changes in oxy- and deoxy-Hb show that the step-related changes in the oxy- and deoxy-Hb signals are negligible compared to the task-related changes. Statistical assessment of the task-related changes in the oxy-Hb signals show that the dorsolateral prefrontal cortex and rostral prefrontal area are significantly activated during the AD task. These results suggest that our functional imaging technique with the WOT system is applicable to OT measurement while walking, and will be a powerful tool for evaluating brain activation in a natural environment.
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Affiliation(s)
- Hirokazu Atsumori
- Hitachi, Ltd., Advanced Research Laboratory, Hatoyama, Saitama, Japan.
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37
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Orihuela-Espina F, Leff DR, James DRC, Darzi AW, Yang GZ. Quality control and assurance in functional near infrared spectroscopy (fNIRS) experimentation. Phys Med Biol 2010; 55:3701-24. [PMID: 20530852 DOI: 10.1088/0031-9155/55/13/009] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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38
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Prefrontal dysfunction in attention-deficit/hyperactivity disorder as measured by near-infrared spectroscopy. Child Psychiatry Hum Dev 2010; 41:193-203. [PMID: 19826946 DOI: 10.1007/s10578-009-0160-y] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Recent developments in near-infrared spectroscopy (NIRS) have enabled non-invasive clarification of brain functions in psychiatric disorders with measurement of hemoglobin concentrations as cerebral blood volume. Twenty medication-naïve children with attention-deficit/hyperactivity disorder (ADHD) and 20 age- and sex-matched healthy control subjects participated in the present study after giving consent. The relative concentrations of oxyhemoglobin (oxy-Hb) were measured with frontal probes every 0.1 s during the Stroop color-word task, using 24-channel NIRS machines. During the Stroop color-word task, the oxy-Hb changes in the control group were significantly larger than that in the ADHD group in the inferior prefrontal cortex, especially in the inferior lateral prefrontal cortex bilaterally. The Stroop color-word task used with NIRS may be one useful measurement to assess prefrontal brain dysfunction in ADHD children.
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Aziz SM, Khambatta F, Vaithianathan T, Thomas JC, Clark JM, Marshall R. A near infrared instrument to monitor relative hemoglobin concentrations of human bone tissue in vitro and in vivo. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2010; 81:043111. [PMID: 20441329 DOI: 10.1063/1.3398450] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
A continuous wave near infrared instrument has been developed to monitor in vivo changes in the hemoglobin concentration of the trabecular compartment of human bone. The transmitter uses only two laser diodes of wavelengths 685 and 830 nm, and the receiver uses a single silicon photodiode operating in the photovoltaic mode. The functioning of the instrument and the depth of penetration of the near infrared signals was determined in vitro using tissue-equivalent phantoms. The instrument achieves a depth of penetration of approximately 2 cm for an optode separation of 4 cm and, therefore, has the capacity to interrogate the trabecular compartment of human bone. The functioning of the instrument was tested in vivo to evaluate the relative oxy-hemoglobin (HbO(2)) and deoxy-hemoglobin (Hb) concentrations of the proximal tibial bone of apparently healthy, normal weight, adult subjects in response to a 3 min on, 5 min off, vascular occlusion protocol. The traces of the relative Hb and HbO(2) concentrations obtained were reproducible in controlled conditions. The instrument is relatively simple and flexible, and offers an inexpensive platform for further studies to obtain normative data for healthy cohorts, and to evaluate disease-specific performance characteristics for cohorts with vasculopathies of bone.
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Affiliation(s)
- Syed Mahfuzul Aziz
- School of Electrical and Information Engineering, University of South Australia, Mawson Lakes, South Australia 5095, Australia.
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40
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Nozawa A, Mizuno T, Asano H, Ide H. Evaluation of Spoken Language Understanding by Oxygenated Hemoglobin Concentration. JOURNAL OF ROBOTICS AND MECHATRONICS 2010. [DOI: 10.20965/jrm.2010.p0003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The subjective understanding of spoken language understanding is quantitatively evaluated by variations in oxygenated hemoglobin concentration measured by near-infrared spectroscopy. English listening comprehension tests consisting of two levels of difficulty were taken by 4 subjects during measurement. A correlation was found between subjective understanding and variations in oxygenated hemoglobin concentration.
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41
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Depth sensitivity analysis of functional near-infrared spectroscopy measurement using three-dimensional Monte Carlo modelling-based magnetic resonance imaging. Lasers Med Sci 2010; 25:431-8. [DOI: 10.1007/s10103-010-0754-4] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2009] [Accepted: 01/04/2010] [Indexed: 10/19/2022]
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42
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Single-trial reconstruction of finger-pinch forces from human motor-cortical activation measured by near-infrared spectroscopy (NIRS). Neuroimage 2009; 47:628-37. [DOI: 10.1016/j.neuroimage.2009.04.050] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2008] [Revised: 03/10/2009] [Accepted: 04/09/2009] [Indexed: 11/22/2022] Open
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Atsumori H, Kiguchi M, Obata A, Sato H, Katura T, Funane T, Maki A. Development of wearable optical topography system for mapping the prefrontal cortex activation. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2009; 80:043704. [PMID: 19405663 DOI: 10.1063/1.3115207] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Optical topography (OT) based on near infrared spectroscopy is effective for measuring changes in the concentrations of oxygenated hemoglobin (oxy-Hb) and deoxygenated hemoglobin (deoxy-Hb) in the brain. It can be used to investigate brain functions of subjects of all ages because it is noninvasive and less constraining for subjects. Conventional OT systems use optical fibers to irradiate the scalp and detect light transmitted through the tissue in the human head, but optical fibers limit the subject's head position, so some small systems have been developed without using optical fibers. These systems, however, have a small number of measurement channels. We developed a prototype of a small, light, and wearable OT system that covers the entire forehead. We measured changes in the concentrations of oxy-Hb and deoxy-Hb in the prefrontal cortex while a subject performed a word fluency task. The results show typical changes in oxy-Hb and deoxy-Hb during the task and suggest that the prototype of our system can be used to investigate functions in the prefrontal cortex.
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Affiliation(s)
- Hirokazu Atsumori
- Advanced Research Laboratory, Hitachi, Ltd., 2520 Akanuma, Hatoyama, Saitama 350-0395, Japan
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Matousek P, Stone N. Emerging concepts in deep Raman spectroscopy of biological tissue. Analyst 2009; 134:1058-66. [PMID: 19475130 DOI: 10.1039/b821100k] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This article reviews emerging Raman techniques for deep, non-invasive characterisation of biological tissues. As generic analytical tools, the new methods pave the way for a host of new applications including non-invasive bone disease diagnosis, chemical characterisation of 'stone-like' materials in urology and cancer detection in a number of organs.
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Affiliation(s)
- Pavel Matousek
- Central Laser Facility, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire, UK OX11 0QX.
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Macleod NA, Matousek P. Deep noninvasive Raman spectroscopy of turbid media. APPLIED SPECTROSCOPY 2008; 62:291A-304A. [PMID: 19007455 DOI: 10.1366/000370208786401527] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Affiliation(s)
- Neil A Macleod
- Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire, OX11 0QX, UK
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Katura T, Sato H, Fuchino Y, Yoshida T, Atsumori H, Kiguchi M, Maki A, Abe M, Tanaka N. Extracting task-related activation components from optical topography measurement using independent components analysis. JOURNAL OF BIOMEDICAL OPTICS 2008; 13:054008. [PMID: 19021388 DOI: 10.1117/1.2981829] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Optical topography (OT) signals measured during an experiment that used activation tasks for certain brain functions contain neuronal-activation induced blood oxygenation changes and also physiological changes. We used independent component analysis to separate the signals and extracted components related to brain activation without using any hemodynamic models. The analysis procedure had three stages: first, OT signals were separated into independent components (ICs) by using a time-delayed decorrelation algorithm; second, task-related ICs (TR-ICs) were selected from the separated ICs based on their mean intertrial cross-correlations; and third, the TR-ICs were categorized by k-means clustering into TR activation-related ICs (TR-AICs) and TR noise ICs (TR-NICs). We applied this analysis procedure to the OT signals obtained from experiments using one-handed finger-tapping tasks. In the averaged waveform of the TR-AICs, a small overshoot can be seen for a few seconds after the onset of each task and a few seconds after it ends, and the averaged waveforms of the TR-NICs have an N-shaped pattern.
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Affiliation(s)
- Takusige Katura
- Hitachi, Ltd., Advanced Research Laboratory, 2520 Akanuma, Hatoyama, Saitama 350-0395, Japan.
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Abla D, Okanoya K. Statistical segmentation of tone sequences activates the left inferior frontal cortex: A near-infrared spectroscopy study. Neuropsychologia 2008; 46:2787-95. [DOI: 10.1016/j.neuropsychologia.2008.05.012] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2007] [Revised: 04/10/2008] [Accepted: 05/13/2008] [Indexed: 11/29/2022]
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Hirabayashi Y, Sato H, Uchida-Ota M, Nakai A, Maki A. Technique for designing and evaluating probe caps used in optical topography of infants using a real head model based on three dimensional magnetic resonance images. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2008; 79:066106. [PMID: 18601442 DOI: 10.1063/1.2948307] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
We have developed an effective technique for aiding the design and evaluating the performance of the probe caps used to perform optical topography (OT) on infants. To design and evaluate a probe cap, it is necessary to determine the measurement positions for conducting OT on the brain surface of subjects. One technique for determining these positions on the brain surface is to find their three-dimensional (3D) coordinates using a 3D magnetic space digitizer, which consists of a 3D magnetic source and a 3D magnetic sensor. The problem with this technique is that it takes a long time to determine all the measurement points on the subject's head and it is difficult to use with infants. It is a particular problem with infants who cannot support their own heads. Therefore, we have developed a real model of an infant subject's head based on 3D magnetic resonance (MR) images. The model is made from an optical-curable resin using 3D computer-aided-format coordinate data taken from 3D MR image-format coordinate data. We have determined the measurement positions on the surface of the model corresponding to a scalp using a 3D magnetic space digitizer and displayed the positions on a 3D MR image of the infant's brain. Using this technique, we then determined the actual 72 measurement positions located over the entire brain surface area for use with our new whole-head probe cap for neonates and infants. This method is useful for evaluating the performance of and designing probe caps.
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Emerging Non-invasive Raman Methods in Process Control and Forensic Applications. Pharm Res 2008; 25:2205-15. [PMID: 18415048 DOI: 10.1007/s11095-008-9587-2] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2008] [Accepted: 04/01/2008] [Indexed: 10/22/2022]
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Utsugi K, Obata A, Sato H, Katsura T, Sagara K, Maki A, Koizumi H. Development of an optical brain-machine interface. ACTA ACUST UNITED AC 2008; 2007:5338-41. [PMID: 18003213 DOI: 10.1109/iembs.2007.4353547] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
We have developed a brain-machine interface (BMI) by using a method based on near-infrared spectroscopy. We call our interface "Optical-BMI". It functions as a practical, unrestrictive, non-invasive brain-switch without the need for large equipment. During an experiment with the prototype system, an operator manipulated external electrically controlled equipment while we measured the corresponding spatiotemporal changes in the hemoglobin concentration in the blood flowing through his or her pre-frontal cortex by using a probe cap with 22 measurement points.
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Affiliation(s)
- Kei Utsugi
- Systems Development Laboratory, Hitachi Ltd., 1099 Ohzenji, Asao, Kawasaki, Kanagawa, Japan.
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