Home » Posts tagged 'Neuromonitoring' (Page 2)
Tag Archives: Neuromonitoring
Fr-016-Two-phase auditory evoked fNIRS responses in sleeping infants
Our research revealed a consistent two-phased fNIRS response indicative of changes in oxygenated blood concentration when infants are exposed to brief, repeated speech segments while asleep. We proposed a method to extract the independent components in the fNIRS responses based on Independent Component Analysis. We hypothesise that two extracted independent components consist of a positive component and a negative component. The extracted components are valuable features that can be used for objectively assessing hearing levels in sleeping infants. Continue reading
Su-061-First Episode Psychosis (FEP) Patients Show Increased Activity in Left Temporal-parietal Junction During Social Interaction
The neural mechanisms underlying symptoms in early psychosis are not well understood. We test the hypothesis that typical and early psychosis patients will differ in the neural responses to live face gaze. Neural activity utilizing functional near-infrared spectroscopy (fNIRS) was measured from 14 first episode psychosis (FEP) patients and 20 typical (TD) individuals participating in a dyadic face-to-face interaction. fNIRS results showed a significantly higher responses in the left supramarginal gyrus (SMG)compared to TD individuals who showed similar changes in the right hemisphere. This difference in neural processing may indicate underlying mechanistic differences that can be utilized for diagnostic purposes. Continue reading
Sa-102-Cerebral tissue oximetry in pediatric population: establishing reference values in TD-NIRS measurements
A large cohort of healthy pediatric subjects has been studied to define the distribution of tissue optical parameters and absolute oximetry values in the frontotemporal brain region via time-domain near-infrared spectroscopy. Results from 350 subjects are presented relative to the differential pathlength factor, absorption and reduced scattering coefficients, distribution, and correlation across auxological and demographic indicators. This study provides valuable insights into the expected cerebral optical properties of the brain in the pediatric population, which can be leveraged to improve the reliability of diffuse optical measurements and simulations. Continue reading
Vi-011-Effects of rTMS and Cue Stimuli on Resting-State Functional Connectivity in Methamphetamine-Dependent Individuals
This research investigated repetitive transcranial magnetic stimulation (rTMS) treatment and drug-related cue stimuli’s effect on orbitofrontal cortex (OFC)-related resting-state functional connectivity (rsFC) in Methamphetamine (METH)-dependent individuals. Using fNIRS signals from healthy and METH-dependent individuals, pre- and post-rTMS treatment, METH-dependent individuals initially showed hyperexcitability, alleviated by rTMS. Healthy participants exhibited increased rsFC post-stimuli, contrasting with decreased connectivity in METH-dependent individuals, indicating inadequate craving suppression. Post-treatment, hyperexcitability decreased, with some connections resembling healthy patterns, suggesting rTMS efficacy in restoring inhibition under drug-related stimuli. These findings deepen understanding of addiction-related neural mechanisms and identify biomarkers for addiction discrimination and intervention efficacy assessment. Continue reading
Fr-005-Repetitive head impacts in Para sports alter brain oxygenation patterns
Para swimmers with limb deficiency are faced with the situation that they must use their head to finish each competition by a hit to the wall. Repetitive head impacts may impair behavioral and brain functions. We therefore investigated neurobehavioral functions of a Para swimmer with dysmelia before and after repetitive head impacts (T1) and without (T2). Behavioral and brain functions decreased from pre to post at T1 but not at T2. Para swimmers with limb deficiency are therefore affected from similar consequences onto brain health that are observed after repeated sport-related concussions. Continue reading
Sa-010-Reliability of fNIRS during a language task in people with aphasia
There is growing interest in using fNIRS to study aphasia, a language disorder caused by stroke, but the reliability of fNIRS in people with aphasia has not been established. We administered a language task to eight adults with aphasia during two fNIRS sessions. Several indices indicated that reliability was fair for the group, but poor for individual subjects and channels. Investigators who use this task with fNIRS should limit inferences to the group level and employ strategies to verify that longitudinal changes are valid, and are not due to normal session-to-session variability. Continue reading
Fr-102-Monitoring Cerebral Hemodynamics and Metabolism with a Hybrid trNIRS/DCS System During Shoulder Surgery
A hybrid light-based instrument that combines time-resolved near-infrared spectroscopy (trNIRS) and diffuse correlation spectroscopy (DCS) was used to measure cerebral blood flow (CBF) and the cerebral metabolic rate of oxygen (CMRO2) in patients undergoing elective shoulder surgeries under general anesthesia. Continuous trNIRS and DCS data acquisition revealed the expected reductions in CBF and CMRO2 following anesthesia induction, demonstrating the ability of the device to detect changes in cerebral perfusion and metabolism during surgery. Continue reading
Fr-095-Non-invasive blood flow calibration using a hybrid time-resolved NIRS/DCS system
This work presents a non-invasive method of calibrating diffuse correlation spectroscopy (DCS) by measuring cerebral blood flow (CBF) using time-resolved NIRS (trNIRS) and hypoxia. A brief period of hypoxia was used to cause a transient decrease in arterial oxygen saturation that acts as a blood flow tracer. For validation, CBF was independently measured using the MRI perfusion method, arterial spin labelling (ASL). Good linear correlation was observed between CBF values from trNIRS and ASL. Using hybrid trNIRS/DCS, the approach was used to track absolute CBF during a hypercapnia challenge. Continue reading
Vi-027-Using fNIRs to explore neural correlates of the clinical progression of Parkinson Disease during the miniBESTest: A protocol for a pilot feasibility study
Parkinson Disease (PD) is a neurodegenerative disorder that results in impaired motor function due to loss of dopamine in the basal ganglia. Functional Near-Infrared Spectroscopy (fNIRS) is a unique technology in PD research because we can observe the brain hemodynamic response during naturalistic movements. The current study aims to determine the feasibility of using fNIRS during common clinical test batteries among people with PD (PwP), specifically in the feasibility of testing protocol, the utility of a range of fNIRS related outcome measures, and collect outcome data to determine the sample size required for future large-scale trials with fNIRS in PwP. Continue reading
Fr-052-Quantifying cerebral metabolic and microvascular parameters during and after the cardiac arrest
Cardiac arrest (CA) is a massive and terrifying health problem. Minimizing the effects of CA on the brain requires quantitative real-time bedside monitoring of the cerebral status. We apply a coherent hemodynamic spectroscopy model to cerebral hemodynamic data from a pig model of the cardiac arrest, which allows for recovering various microvascular and metabolic parameters of the brain. This provides valuable knowledge of the impact of CA on the brain and ways to improve treatment. In the future our approach may lead to a clinical non-invasive technique for measuring microvascular and metabolic parameters in CA patients. Continue reading