20 research outputs found

    Multimodal examination of emotion processing systems associated with negative affectivity across early childhood

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    High Temperamental Negative Affectivity in early childhood has been found to predict later emotion dysregulation. While much work has been conducted to separately probe bio-behavioral systems associated with Negative Affectivity, very little work has examined the relations among multiple systems across age. In this study, we use multi-modal methods to index neurobiological systems associated with Negative Affectivity in 53 4-7-year-old children. Prefrontal activation during emotion regulation was measured using functional near-infrared spectroscopy over the lateral prefrontal cortex (PFC) while children played a game designed to elicit frustration in Social (Happy and Angry faces) and Nonsocial contexts. Gaze behaviors while free-viewing Happy and Angry faces were also measured. Finally, Negative Affectivity was indexed using a score composite based on factor analysis of parent-reported temperament. Using mixed-effects linear models, we found an age-dependent association between Negative Affectivity and both PFC activation during frustration and fixation duration on the mouth area of Happy faces, such that older children high in Negative Affectivity spent less time looking at the mouths of Happy faces and had lower PFC activation in response to frustration (ps\u3c0.034). These results provide further insight to how Negative Affectivity may be associated with changes in affective neurobiological systems across early childhood

    Measuring the Impact of Walking Environments on Brain Activation: Results from an fNIRS Pilot Study

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    Studying the impact of built urban environments on pedestrians' walking experience can improve our understanding of the environmental factors that influence perceived walkability. This can contribute to the design of pleasant urban environments that promote better health and well-being for city residents. However, evidence-based research on perceptions of walkability is still limited. Research has demonstrated that functional near-infrared spectroscopy (fNIRS), an optical brain imaging technique, can measure cortical neural activation. Some studies have employed fNIRS to investigate brain activation by contrasting built and natural environments; however, little research has used fNIRS to investigate the effect of built urban environments on brain activity. Therefore, the aim of this study was to apply fNIRS to measure the effect of different built urban environments on prefrontal cortex activation. The present article presents preliminary results from a pilot study involving five participants (one female, age 31.4 ± 5.1 years). While we measured their prefrontal cortex (PFC) oxyhemoglobin (HbO) and deoxyhemoglobin (HbR), participants watched nine 20-second videos of urban environments from a pedestrian's perspective in a laboratory setting. Viewing pleasant walking environments led to a significant decrease in HbO concentrations in the right and central regions of the PFC, indicating physiological relaxation. This study demonstrates the feasibility of using fNIRS to study the built environment and opens up promising opportunities to explore the relationship between urban environments and pedestrians' experiences

    Decoding Working-Memory Load During n-Back Task Performance from High Channel NIRS Data

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    Near-infrared spectroscopy (NIRS) can measure neural activity through blood oxygenation changes in the brain in a wearable form factor, enabling unique applications for research in and outside the lab. NIRS has proven capable of measuring cognitive states such as mental workload, often using machine learning (ML) based brain-computer interfaces (BCIs). To date, NIRS research has largely relied on probes with under ten to several hundred channels, although recently a new class of wearable NIRS devices with thousands of channels has emerged. This poses unique challenges for ML classification, as NIRS is typically limited by few training trials which results in severely under-determined estimation problems. So far, it is not well understood how such high-resolution data is best leveraged in practical BCIs and whether state-of-the-art (SotA) or better performance can be achieved. To address these questions, we propose an ML strategy to classify working-memory load that relies on spatio-temporal regularization and transfer learning from other subjects in a combination that has not been used in previous NIRS BCIs. The approach can be interpreted as an end-to-end generalized linear model and allows for a high degree of interpretability using channel-level or cortical imaging approaches. We show that using the proposed methodology, it is possible to achieve SotA decoding performance with high-resolution NIRS data. We also replicated several SotA approaches on our dataset of 43 participants wearing a 3198 dual-channel NIRS device while performing the n-Back task and show that these existing methods struggle in the high-channel regime and are largely outperformed by the proposed method. Our approach helps establish high-channel NIRS devices as a viable platform for SotA BCI and opens new applications using this class of headset while also enabling high-resolution model imaging and interpretation.Comment: 29 pages, 9 figures. Under revie

    Acute effects of subanesthetic ketamine on cerebrovascular hemodynamics in humans: A TD-fNIRS neuroimaging study

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    Quantifying neural activity in natural conditions (i.e. conditions comparable to the standard clinical patient experience) during the administration of psychedelics may further our scientific understanding of the effects and mechanisms of action. This data may facilitate the discovery of novel biomarkers enabling more personalized treatments and improved patient outcomes. In this single-blind, placebo-controlled study with a non-randomized design, we use time-domain functional near-infrared spectroscopy (TD-fNIRS) to measure acute brain dynamics after intramuscular subanesthetic ketamine (0.75 mg/kg) and placebo (saline) administration in healthy participants (n= 15, 8 females, 7 males, age 32.4 ± 7.5 years) in a clinical setting. We found that the ketamine administration caused an altered state of consciousness and changes in systemic physiology (e.g. increase in pulse rate and electrodermal activity). Furthermore, ketamine led to a brain-wide reduction in the fractional amplitude of low frequency fluctuations (fALFF), and a decrease in the global brain connectivity of the prefrontal region. Lastly, we provide preliminary evidence that a combination of neural and physiological metrics may serve as predictors of subjective mystical experiences and reductions in depressive symptomatology. Overall, our studies demonstrated the successful application of fNIRS neuroimaging to study the physiological effects of the psychoactive substance ketamine and can be regarded as an important step toward larger scale clinical fNIRS studies that can quantify the impact of psychedelics on the brain in standard clinical settings

    Surface-based integration approach for fNIRS-fMRI reliability assessment

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    Introduction: Studies integrating functional near-infrared spectroscopy (fNIRS) with functional MRI (fMRI) employ heterogeneous methods in defining common regions of interest in which similarities are assessed. Therefore, spatial agreement and temporal correlation may not be reproducible across studies. In the present work, we address this issue by proposing a novel method for integration and analysis of fNIRS and fMRI over the cortical surface. Materials and methods: Eighteen healthy volunteers (age mean±SD 30.55 Â± 4.7, 7 males) performed a motor task during non-simultaneous fMRI and fNIRS acquisitions. First, fNIRS and fMRI data were integrated by projecting subject- and group-level source maps over the cortical surface mesh to define anatomically constrained functional ROIs (acfROI). Next, spatial agreement and temporal correlation were quantified as Dice Coefficient (DC) and Pearson's correlation coefficient between fNIRS-fMRI in the acfROIs. Results: Subject-level results revealed moderate to substantial spatial agreement (DC range 0.43 - 0.64), confirmed at the group-level only for blood oxygenation level-dependent (BOLD) signal vs. HbO2 (0.44 - 0.69), while lack of agreement was found for BOLD vs. HbR in some instances (0.05 - 0.49). Subject-level temporal correlation was moderate to strong (0.79 - 0.85 for BOLD vs. HbO2 and -0.62 to -0.72 for BOLD vs. HbR), while an overall strong correlation was found for group-level results (0.95 - 0.98 for BOLD vs. HbO2 and -0.91 to -0.94 for BOLD vs. HbR). Conclusion: The proposed method directly compares fNIRS and fMRI by projecting individual source maps to the cortical surface. Our results indicate spatial and temporal correspondence between fNIRS and fMRI, and promotes the use of fNIRS when more ecological acquision settings are required, such as longitudinal monitoring of brain activity before and after rehabilitation

    Adversity is linked with decreased parent-child behavioral and neural synchrony

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    Parent-child synchrony-parent-child interaction patterns characterized by contingent social responding, mutual responsivity, and co-regulation-has been robustly associated with adaptive child outcomes. Synchrony has been investigated in both behavioral and biological frameworks. While it has been demonstrated that adversity can influence behavioral parent-child synchrony, the neural mechanisms by which this disruption occurs are understudied. The current study examined the association between adversity, parent-child behavioral synchrony, and parent-child neural synchrony across lateral prefrontal cortical regions using functional near-infrared spectroscopy hyperscanning during a parent-child interaction task that included a mild stress induction followed by a recovery period. Participants included 115 children (ages 4-5) and their primary caregivers. Parent-child behavioral synchrony was quantified as the amount time the dyad was synchronous (e.g., reciprocal communication, coordinated behaviors) during the interaction task. Parent-child neural synchrony was examined as the hemodynamic concordance between parent and child lateral PFC activation. Adversity was examined across two, empirically-derived domains: sociodemographic risk (e.g., family income) and familial risk (e.g., household chaos). Adversity, across domains, was associated with decreased parent-child behavioral synchrony across task conditions. Sociodemographic risk was associated with decreased parent-child neural synchrony in the context of experimentally-induced stress. These findings link adversity to decreased parent-child behavioral and neural synchrony

    Adaptive yoga versus low-impact exercise for adults with chronic acquired brain injury: a pilot randomized control trial protocol

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    BackgroundEach year, millions of Americans sustain acquired brain injuries (ABI) which result in functional impairments, such as poor balance and autonomic nervous system (ANS) dysfunction. Although significant time and energy are dedicated to reducing functional impairment in acute phase of ABI, many individuals with chronic ABI have residual impairments that increase fall risk, decrease quality of life, and increase mortality. In previous work, we have found that yoga can improve balance in adults with chronic (i.e., ≥6 months post-injury) ABI. Moreover, yoga has been shown to improve ANS and brain function in healthy adults. Thus, adults with chronic ABI may show similar outcomes. This protocol details the methods used to examine the effects of a group yoga program, as compared to a group low-impact exercise, on primary and secondary outcomes in adults with chronic ABI.MethodsThis study is a single-blind randomized controlled trial comparing group yoga to group low-impact exercise. Participants must be ≥18 years old with chronic ABI and moderate balance impairments. Group yoga and group exercise sessions occur twice a week for 1 h for 8 weeks. Sessions are led by trained adaptive exercise specialists. Primary outcomes are balance and ANS function. Secondary outcomes are brain function and structure, cognition, quality of life, and qualitative experiences. Data analysis for primary and most secondary outcomes will be completed with mixed effect statistical methods to evaluate the within-subject factor of time (i.e., pre vs. post intervention), the between-subject factor of group (yoga vs. low-impact exercise), and interaction effects. Deductive and inductive techniques will be used to analyze qualitative data.DiscussionDue to its accessibility and holistic nature, yoga has significant potential for improving balance and ANS function, along with other capacities, in adults with chronic ABI. Because there are also known benefits of exercise and group interaction, this study compares yoga to a similar, group exercise intervention to explore if yoga has a unique benefit for adults with chronic ABI.Clinical trial registration:ClinicalTrials.gov, NCT05793827. Registered on March 31, 2023

    Adaptative computerized cognitive training decreases mental workload during working memory precision task. A preliminary fNIRS study.

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    With the growing concern for the health of ageing populations, much research continues to look at the impact of cognitive training, particularly in relation to cognitive decline. We sought to use novel techniques, including augmented reality and portable neurotechnology, to evaluate the impact of a dynamically adjusting cognitive training programme, in comparison to a statically challenging alternative. Before and after an 8-week training period, and at a 5-week follow-up, we used portable functional Near Infrared Spectroscopy to examine mental workload in a mixed battery of cognitive and transfer tasks. A recently developed tablet-based task was used to identify changes in cognitive misbinding. Augmented Reality was used to create a supermarket shopping experience, as a more ecologically valid and realistic transfer task relating to an everyday task relating to independence that quickly becomes difficult with cognitive decline. The analyses showed a decreased mental workload within the dorsolateral prefrontal cortex and that participants considerably increased their performance in the trained task. Some results were maintained at the 5-week follow-up assessment. In terms of transfer, we observed reliable group differences immediately after training completion, which were mainly driven by distinct conditions. Some behavioural memory gains were maintained during the follow-up. The use of novel technologies brought new insights into the effects produced by the dynamic computerised cognitive training programme, which has potential future applications in cognitive decline screening and prevention
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