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Lei Liu, Wataru Ito, Alexei Morozov
Region and cell-type restricted expression of light-activated ion channels is the indispensable tool to study properties of synapses in specific circuits and to monitor synaptic alterations by various stimuli including neuromodulators and behaviors, both ex vivo and in vivo . These analyses require the light-activated proteins or viral vectors for their delivery that do not interfere with the phenomenon under study. Here, we report a case of such interference in which the high-level expression of channelrhodopsin-2 introduced in the somatostatin-positive GABAergic neurons of the dorsomedial prefrontal cortex by an adeno-associated virus vector weakens the presynaptic GABAb receptor-mediated suppression of GABA release...
April 2018: Neurophotonics
Jianwei Cao, Hanli Liu, George Alexandrakis
Cortical circuit reorganization induced by anodal transcranial direct current stimulation (tDCS) over the Broca's area of the dominant language hemisphere in 13 healthy adults was quantified by functional near-infrared spectroscopy (fNIRS). Transient cortical reorganization patterns in steady-state functional connectivity (seed-based and graph theory analysis) and temporal functional connectivity (sliding window correlation analysis) were recorded before, during, and after applying high current tDCS (1 mA, 8 min)...
April 2018: Neurophotonics
Jonathan R Bumstead, Jasmine J Park, Isaac A Rosen, Andrew W Kraft, Patrick W Wright, Matthew D Reisman, Daniel C Côté, Joseph P Culver
Conventional two-photon microscopy (TPM) is capable of imaging neural dynamics with subcellular resolution, but it is limited to a field-of-view (FOV) diameter [Formula: see text]. Although there has been recent progress in extending the FOV in TPM, a principled design approach for developing large FOV TPM (LF-TPM) with off-the-shelf components has yet to be established. Therefore, we present a design strategy that depends on analyzing the optical invariant of commercially available objectives, relay lenses, mirror scanners, and emission collection systems in isolation...
April 2018: Neurophotonics
Swati M Surkar, Rashelle M Hoffman, Regina Harbourne, Max J Kurz
The primary aim of the study was to explore the prefrontal cortical (PFC) activation while performing a shape-matching motor task in children with hemiplegic cerebral palsy (HCP) as compared with typically developing (TD) children. Fifteen TD children ([Formula: see text]) and 12 children with HCP ([Formula: see text]) were included. We assessed the PFC activation while performing an ecologically valid upper extremity shape-matching task of different complexities by measuring the concentration of oxygenated hemoglobin (HbO) using functional near-infrared spectroscopy...
January 2018: Neurophotonics
Ruiqing Ni, Markus Vaas, Wuwei Ren, Jan Klohs
Oxygen metabolism and matrix metalloproteinases (MMPs) play important roles in the pathophysiology of cerebral ischemia. Using multispectral optoacoustic tomography (MSOT) imaging, we visualized in vivo changes in cerebral tissue oxygenation during 1 h of transient middle cerebral artery occlusion (tMCAO) and at 48 h after reperfusion together with MMP activity using an MMP-activatable probe. The deoxyhemoglobin, oxyhemoglobin, and MMP signals were coregistered with structural magnetic resonance imaging data...
January 2018: Neurophotonics
Hannah F Behrendt, Christine Firk, Charles A Nelson, Katherine L Perdue
Correcting for motion is an important consideration in infant functional near-infrared spectroscopy studies. We tested the performance of conventional motion correction methods and compared probe motion and data quality metrics for data collected at different infant ages (5, 7, and 12 months) and during different methods of stimulus presentation (video versus live). While 5-month-olds had slower maximum head speed than 7- or 12-month-olds, data quality metrics and hemodynamic response recovery errors were similar across ages...
January 2018: Neurophotonics
Sahar Jahani, Seyed K Setarehdan, David A Boas, Meryem A Yücel
Motion artifact contamination in near-infrared spectroscopy (NIRS) data has become an important challenge in realizing the full potential of NIRS for real-life applications. Various motion correction algorithms have been used to alleviate the effect of motion artifacts on the estimation of the hemodynamic response function. While smoothing methods, such as wavelet filtering, are excellent in removing motion-induced sharp spikes, the baseline shifts in the signal remain after this type of filtering. Methods, such as spline interpolation, on the other hand, can properly correct baseline shifts; however, they leave residual high-frequency spikes...
January 2018: Neurophotonics
Yoo Hwan Kim, Zephaniah Phillips V, Seung-Ho Paik, Nam-Joon Jeon, Beop-Min Kim, Byung-Jo Kim
The Valsalva maneuver (VM) with beat-to-beat blood pressure and heart rate monitoring are used to evaluate orthostatic intolerance (OI). However, they lack the ability to detect cerebral hemodynamic changes, which may be a cause of OI symptoms. Therefore, we utilized near-infrared spectroscopy during VM. Patients with OI symptoms and normal healthy subjects were recruited. Patients were subgrouped according to VM results: patients with normal VM (NVM) and abnormal VM (AbVM). Oxyhemoglobin (HbO), deoxyhemoglobin, and total hemoglobin changes were measured at four different source-detector distances (SD) (15, 30, 36, and 45 mm), and latency, amplitude, duration, and integrated total signal were calculated...
January 2018: Neurophotonics
Martina Giovannella, David Ibañez, Clara Gregori-Pla, Michal Kacprzak, Guillem Mitjà, Giulio Ruffini, Turgut Durduran
Transcranial direct current stimulation (tDCS) is currently being used for research and treatment of some neurological and neuropsychiatric disorders, as well as for improvement of cognitive functions. In order to better understand cerebral response to the stimulation and to redefine protocols and dosage, its effects must be monitored. To this end, we have used functional diffuse correlation spectroscopy (fDCS) and time-resolved functional near-infrared spectroscopy (TR-fNIRS) together with electroencephalography (EEG) during and after stimulation of the frontal cortex...
January 2018: Neurophotonics
Stefania Lancia, Vincenza Cofini, Marika Carrieri, Marco Ferrari, Valentina Quaresima
The Corsi block-tapping test (CBT) is an old neuropsychological test that, requiring the storage and the reproduction of spatial locations, assesses spatial working memory (WM). Despite its wide use in clinical practice, the specific contribution of prefrontal cortex (PFC) subregions during CBT execution has not been clarified yet. Considering the importance of spatial WM in daily life and the well-known role of ventrolateral-PFC/dorsolateral-PFC (VLPFC/DLPFC) in WM processes, the present study was aimed at investigating, by a 20-channel functional near-infrared spectroscopy (fNIRS) system (including four short-separation channels), the hemodynamic response of the VLPFC/DLPFC during a computerized version of the CBT...
January 2018: Neurophotonics
Yoko Hakuno, Laura Pirazzoli, Anna Blasi, Mark H Johnson, Sarah Lloyd-Fox
Despite the importance of our ability to interact and communicate with others, the early development of the social brain network remains poorly understood. We examined brain activity in 12- to 14-month-old infants while they were interacting live with an adult in two different naturalistic social scenarios (i.e., reading a picture book versus singing nursery rhymes with gestures), as compared to baseline (i.e., showing infants a toy without eye contact or speech). We used functional near-infrared spectroscopy (fNIRS) recorded over the right temporal lobe of infants to assess the role of the superior temporal sulcus-temporoparietal junction (STS-TPJ) region during naturalistic social interactions...
January 2018: Neurophotonics
Ke Peng, Meryem A Yücel, Christopher M Aasted, Sarah C Steele, David A Boas, David Borsook, Lino Becerra
Currently, there is no method for providing a nonverbal objective assessment of pain. Recent work using functional near-infrared spectroscopy (fNIRS) has revealed its potential for objective measures. We conducted two fNIRS scans separated by 30 min and measured the hemodynamic response to the electrical noxious and innocuous stimuli over the anterior prefrontal cortex (aPFC) in 14 subjects. Based on the estimated hemodynamic response functions (HRFs), we first evaluated the test-retest reliability of using fNIRS in measuring the pain response over the aPFC...
January 2018: Neurophotonics
Suelen Rosa de Oliveira, Ana Carolina Cabral de Paula Machado, Jonas Jardim de Paula, Paulo Henrique Paiva de Moraes, Maria Juliana Silvério Nahin, Lívia de Castro Magalhães, Sergio L Novi, Rickson C Mesquita, Débora Marques de Miranda, Maria Cândida Ferrarez Bouzada
This study aimed to assess task-induced activation in motor cortex and its association with motor performance in full-term and preterm born infants at six months old. A cross-sectional study of 73 six-month-old infants was conducted (35 full-term and 38 preterm infants). Motor performance was assessed using the Bayley Scales of Infant Development third edition-Bayley-III. Brain hemodynamic activity during motor task was measured by functional near-infrared spectroscopy (fNIRS). Motor performance was similar in full-term and preterm infants...
January 2018: Neurophotonics
Amy Hirshkowitz, Marisa Biondi, Teresa Wilcox
Our ability to extract three-dimensional (3-D) object structure from motion-carried information is a basic visual capacity that is fundamental to object perception. Despite a rich body of behavioral work demonstrating that infants are sensitive to motion-carried information from the early months of life, little is known about the cortical networks that support infants' use of motion-carried information to extract 3-D object structure. This study assessed patterns of cortical activation in infants aged 4 to 6 months as they viewed two types of visual stimuli: (a) shape-from-motion (SFM) displays, where coherent motion of randomly distributed dots gave rise to the percept of 3-D shape and (b) random motion (RM) displays, where dots' motions lacked a coherent structure and gave rise to the percept of randomly moving dots...
January 2018: Neurophotonics
Gentaro Taga, Hama Watanabe, Fumitaka Homae
Spontaneous low-frequency oscillatory changes in oxygenated hemoglobin (oxy-Hb) and deoxygenated hemoglobin (deoxy-Hb) are observed using functional near-infrared spectroscopy (fNIRS). A previous study showed that the time-averaged phase difference between oxy-Hb and deoxy-Hb changes, referred to as hemoglobin phase of oxygenation and deoxygenation (hPod), is sensitive to the development of the cortex. We examined phase-locking index of hPod, referred to as [Formula: see text], in addition to hPod, in neonates and 3- and 6-month-old infants using the 94-channel fNIRS data, which covered large lateral regions of the cortex...
January 2018: Neurophotonics
Drew W R Halliday, Bryce P Mulligan, Douglas D Garrett, Stefan Schmidt, Sandra R Hundza, Mauricio A Garcia-Barrera, Robert S Stawski, Stuart W S MacDonald
OBJECTIVE: although the preponderance of research on functional brain activity investigates mean group differences, mounting evidence suggests that variability in neural activity is beneficial for optimal central nervous system (CNS) function. Independent of mean signal estimates, recent findings have shown that neural variability diminishes with age and is positively associated with cognitive performance, underscoring its adaptive nature. The present investigation sought to employ functional near infrared spectroscopy (fNIRS) to derive two operationalizations of cerebral oxygenation, representing mean and variability [using standard deviation (SD)] in neural activity, and to specifically contrast these mean- and SD-oxyhemoglobin (HbO) estimates as predictors of cognitive function...
January 2018: Neurophotonics
Hubin Zhao, Robert J Cooper
The development of a whole-scalp, high sampling-density diffuse optical tomography (DOT) system is a critical next step in the evolution of the field of diffuse optics. To achieve this with optical fiber bundles is extremely challenging, simply because of the sheer number of bundles required, and the associated challenges of weight and ergonomics. Dispensing with optical fiber bundles and moving to head-mounted optoelectronics can potentially facilitate the advent of a new generation of wearable, whole-scalp technologies that will open up a range of new experimental and clinical applications for diffuse optical measurements...
January 2018: Neurophotonics
David Perpetuini, Roberta Bucco, Michele Zito, Arcangelo Merla
Working memory deficit is a signature of Alzheimer's disease (AD). The free and cued selective reminding test (FCSRT) is a clinical test that quantifies memory deficit for AD diagnosis. However, the diagnostic accuracy of FCSRT may be increased by accompanying it with neuroimaging. Since the test requires doctor-patient interaction, brain monitoring is challenging. Functional near-infrared spectroscopy (fNIRS) could be suited for such a purpose because of the fNIRS flexibility. We investigated whether the complexity, based on sample entropy and multiscale entropy metrics, of the fNIRS signal during FCSRT was correlated with memory deficit in early AD...
January 2018: Neurophotonics
Davide Tamborini, Parisa Farzam, Bernhard Zimmermann, Kuan-Cheng Wu, David A Boas, Maria Angela Franceschini
This paper presents a multidistance and multiwavelength diffuse correlation spectroscopy (DCS) approach and its implementation to simultaneously measure the optical proprieties of deep tissue as well as the blood flow. The system consists of three long coherence length lasers at different wavelengths in the near-infrared, eight single-photon detectors, and a correlator board. With this approach, we collect both light intensity and DCS data at multiple distances and multiple wavelengths, which provide unique information to fit for all the parameters of interest: scattering, blood flow, and hemoglobin concentration...
January 2018: Neurophotonics
Felipe Orihuela-Espina, Daniel R Leff, David R C James, Ara W Darzi, Guang-Zhong Yang
This paper describes the Imperial College near infrared spectroscopy neuroimaging analysis (ICNNA) software tool for functional near infrared spectroscopy neuroimaging data. ICNNA is a MATLAB-based object-oriented framework encompassing an application programming interface and a graphical user interface. ICNNA incorporates reconstruction based on the modified Beer-Lambert law and basic processing and data validation capabilities. Emphasis is placed on the full experiment rather than individual neuroimages as the central element of analysis...
January 2018: Neurophotonics
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