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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-044-Multimodal Near-Infrared Spectroscopy and 9.4T MRI shows reduced perfusion and abnormal oxidative metabolism in the EAE mouse model of MS
While multiple sclerosis (MS) is typically considered a white matter disease, there is prominent evidence that gray matter pathology, such as hypoxia, disruptions in metabolic rate and mitochondrial dysfunction are involved as well. We are applying a novel multimodal technique combining near-infrared spectroscopy and high-field MRI to study the mitochondrial status as well as oxygen delivery and consumption in the cortex of the EAE mouse model of MS. Reduced perfusion, and consequent hypoxia, with abnormal mitochondrial regulation and no change in consumption rate were found in EAE mice. Hypoxia and mitochondrial damage are likely to exacerbate the pathology in MS. Continue reading
Fr-039-Aberrant Neural Response and Eye Gaze Pattern in Girls with Fragile X Syndrome
Fragile X syndrome (FXS) presents significant challenges in social interaction, yet understanding the neural mechanisms and associated behaviors in affected individuals remains limited. We employed fNIRS and eye gaze tracking to investigate brain dynamics and eye gaze behavior during face-to-face conversation in 35 girls with FXS and 31 matched controls. FXS girls exhibited hyperactivity in prefrontal and temporal cortical areas alongside reduced eye contact and aberrant gaze patterns. Correlational analyses showed a close association between the aberrant brain activity and gaze behaviors. These findings shed light on FXS's neural underpinnings in social contexts, offering potential targets for therapeutic interventions. Continue reading
Fr-038-Left fetal temporal sulcus depth predicts speech discrimination abilities at birth
This pilot study examined the longitudinal relationship between superior temporal sulcus (STS) depth in fetuses and their speech discrimination abilities at birth. Overall, neonates had a significantly larger hemodynamic response to forward than to backward speech, particularly in the left hemisphere. Importantly, a deeper left fetal STS correlated with decreased activation within the right hemisphere during neonatal speech discrimination. We hypothesize that earlier fetal development of the left STS is beneficial for speech perception abilities at birth. Continue reading
Fr-061-Building behavioral and neural foundations for infant fNIRS-neurofeedback
The aim of the current study was to ascertain the feasibility of developing an fNIRS-neurofeedback protocol for infants. The first part of the study was to ensure an effective training paradigm by assessing spontaneous infant preferences of visual stimuli. Building on these findings, we designed a training paradigm that will intrinsically motivate specific neural features. In the second part, we conducted preliminary tests of the task to determine offline the best online signal processing and neurofeedback algorithm. Combined, these findings will provide the foundation for future research to develop a protocol for infant fNIRS-neurofeedback. Continue reading
Vi-004-Improvements in fNIRS-BCI Classification through Integrated Contextual Gate Networks
Abstract: Brain-computer interface (BCI) systems include signal acquisition, preprocessing, feature extraction, classification, and an application phase. This study employs z-score normalization and an Integrated Contextual Gate Network (ICGN) algorithm to enhance fNIRS-based BCIs classification accuracy. Results demonstrate ICGN's superiority over long short-term memory (LSTM) and bidirectional long short-term memory (Bi-LSTM) algorithms, achieving a classification accuracy of 91.23% ± 1.60%. Additionally, the algorithm's efficiency extends to two-class as well as three-class datasets, showcasing its potential for real-time fNIRS-BCI applications. Continue reading
Fr-057-Prefrontal cortex activity associated with hand dexterity – A Functional Near-Infrared Spectroscopy Study –
We investigated the association between hand dexterity and prefrontal cortex activity using functional near-infrared spectroscopy (fNIRS). Twenty right-handed adults participated in experiments in which the Purdue Pegboard Test was used to assess hand dexterity and fNIRS was used to measure cortical activation during a pin-manipulation task requiring dexterity. Statistical analysis revealed increased activity in the contralateral sensorimotor cortex during the pin-manipulation task compared with the control task. In addition, prefrontal cortex activity during the pin-manipulation task correlated with hand dexterity scores. These results suggest a relationship between hand dexterity and prefrontal cortex activity during the pin-manipulation task. Continue reading
Fr-056-Development of an fNIRS-based neurofeedback system using prefrontal asymmetry
Previous studies suggest that “choking under pressure” in sports is associated with asymmetry in prefrontal cortex (PFC) activity, with performance being higher during left hemisphere dominance. In this study, we aimed to develop a neurofeedback system using function near-infrared spectroscopy (fNIRS) based on this finding. This system was developed using a 2-channel fNIRS device and smartphone to provide musical feedback on asymmetry in PFC activity. The effectiveness of the system was evaluated in a preliminary experiment with six participants and the results were positive. Continue reading
Vi-003-Use fNIRS Hyperscanning to Investigate the Effect of Risk Preference on Dyadic Decision
Used fNIRS hyperscanning to investigate the effect of risk preference on dyadic decision. Firstly, used sequential decision task to measure subjects' risk preferences as baseline, and then paired subjects into “risk-risk”, “risk-conservative”, and “conservative-conservative” groups to perform a self-designed dyadic version of sequential risk taking task with fNIRS hyperscanning. Ultimately, we found that the “risk-risk” group got the most rewards, had the fewest number of disagreements in the experiment, and showed greater interpersonal brain synchronization. In conclusion, the “risk-risk” group had a higher quality of risky decision making in the risk-seeking context. Continue reading
Fr-083-Specificity of NIRS-based neurofeedback – Effects of inferior frontal gyrus (IFG) vs.dorsolateral prefrontal cortex (DLPFC) training in highly-impulsive individuals
Neurofeedback (NF) is a method of non-invasive neuromodulation. For the treatment of ADHD, different protocols have been proposed, with the inferior frontal gyrus (IFG) and dorsolateral prefrontal cortex (DLPFC) most frequently targeted. In the present study, we directly compared both protocols in highly-impulsive individuals using eight sessions of fNIRS-NF. We found significant correlations between learning of self-regulation within the DLPFC and IFG, but not a temporal cortex control area. Also, more efficient frontal neural processing during an n-back task occurred following IFG (and partly also DLPFC) NF. We conclude that fNIRS-based frontal NF elicits specific neurocognitive changes; however, the current setup did not specifically target the IFG vs. DLPFC region. Continue reading