Hemodynamic Activity Research Articles

Hemodynamic analysis of coil filled patient-specific middle cerebral artery aneurysm using porous medium approach

Cerebral aneurysms are bulges of an artery, which could be life-threatening when ruptured. Depending on their size, shape, and location, they need to be managed either through clipping or an endovascular coiling intervention. When coiled, reduced hemodynamic activity enables the coil to get thrombosed and achieve flow stasis. However, some coils delivered into the aneurysm tend to prolapse into the parent vessel and cause stroke due to obstruction and embolization. The recurrence of an aneurysm after endovascular coiling is of concern in the treatment of wide necked aneurysms. The initial packing density or improper coiling of the aneurysm and its relation to recurrence remains uncertain. This study investigates the influence of reduction in coil fill volume and packing density on the aneurysm recurrence using hemodynamic parameters by analyzing its flow features. Finite element method based commercial computational fluid dynamics solver is employed for performing patient-specific simulations for the coil filled aneurysm. The present approach uses porous medium based formulation. The numerical simulations show that any reduction below the optimal coil fill volume and packing density inside the aneurysm increases the velocity magnitude, wall shear stress, time-averaged wall shear stress, and spatial gradient of wall shear stress and reduces the relative residence time. The hemodynamic parameters and flow features suggest that a reduction in the coil packing density inside the aneurysm increases the chances of aneurysm recurrence. Hence, an assessment on how to achieve optimal coil fill volume and packing density is critical in reducing the risk of aneurysm recurrence.

FNIRS-based evaluation of the impact of SARS-CoV-2 infection central auditory processing.

Coronavirus disease-2019 due to SARS-CoV-2 infection has been associated with neurological and neuropsychiatric illnesses as well as auditory system problems. In this study, we aimed to evaluate the impact of SARS-CoV-2 infection on the central auditory system by assessing the hemodynamic activation changes using functional near-infrared spectroscopy (fNIRS). Three participants who had SARS-CoV-2 infection (study group) and four participants who had no SARS-CoV-2 infection (control group) were included in the study. During the auditory oddball task in which two different frequencies of tonal stimulation were presented at 80dB HL, the participants were asked to pay attention to the rare tonal stimulation and mentally count these target stimuli throughout the task. During this task, oxygenated hemodynamic response functions were evaluated with fNIRS. Significantly increased oxygenated hemodynamic responses were observed in both groups during the task (p<.05), which was significantly higher in the study group (p<.05). Significantly more HbO activation was observed in the vmPFC, superior temporal gyrus, and medial temporal gyrus in the study group compared to controls (p<.05). Significantly higher hemodynamic activation was observed in the right hemisphere in both groups, which was significantly higher in the study group (p<.05). SARS-CoV-2 infections may impact on central auditory processing or auditory attention due to changes in oxyhemoglobin levels in the frontal and temporal brain regions. It seems that SARS-CoV-2 infection is associated with an additional load on neural activity, and difficulties in focusing in auditory attention, following speech and hearing in noise as well as increased effort to perceive auditory cues.

Longitudinal changes in human supraspinal processing after RIII-feedback training to improve descending pain inhibition

The human body has the ability to influence its sensation of pain by modifying the transfer of nociceptive information at the spinal level. This modulation, known as descending pain inhibition, is known to originate supraspinally and can be activated by a variety of ways including positive mental imagery. However, its exact mechanisms remain unknown. We investigated, using a longitudinal fMRI design, the brain activity leading up and in response to painful electrical stimulation when applying positive mental imagery before and after undergoing a previously established RIII-feedback paradigm. Time course analysis of the time preceding painful stimulation shows increased haemodynamic activity during the application of the strategy in the PFC, ACC, insula, thalamus, and hypothalamus. Time course analysis of the reaction to painful stimulation shows decreased reaction post-training in brainstem and thalamus, as well as the insula and dorsolateral PFC. Our work suggests that feedback training increases activity in areas involved in pain inhibition, while simultaneously decreasing the reaction to painful stimuli in brain areas related to pain processing, which points to an activation of decreased spinal nociception. We further suggest that the insula and the thalamus may play a more important role in pain modulation than previously assumed.

Positive effects of brisk walking and Tai Chi on cognitive function in older adults: An fNIRS study

Exercise has shown to have beneficial effects on cognition in older adults. The purpose of this study was to investigate the cortical hemodynamic responses during the word-color Stroop test (WCST) prior and after acute walking and Tai Chi exercise by functional near-infrared spectroscopy (fNIRS). Twenty participants (9 males, mean age 62.8 ± 5.2), first underwent a baseline WCST test, after which they took three WCST tests in a randomized order, (a) after sitting rest (control), (b) after 6 minutes performing Tai Chi Quan, and (c) after a bout of 6 minutes brisk walking. During these four WCST tests cortical hemodynamic changes in the prefrontal area were monitored with fNIRS. Both brisk walking and Tai Chi enhanced hemodynamic activity during the Stroop incongruent tasks, leading to improved cognitive performance (quicker reaction time). Brisk walking induced a greater hemodynamic activity in the right dorsolateral prefrontal cortex (DLPFC) and ventrolateral prefrontal cortex (VLPFC) area, whereas Tai Chi induced a greater bilateral hemodynamic activity in the DLPFC and VLPFC areas. The present study provided empirical evidence of enhanced hemodynamic response in task- specific regions of the brain that can be achieved by a mere six minutes of brisk walking or Tai Chi in older adults.

Ultra-conductive and transparent epidermal electrodes for simultaneous dual-mode assessment of brain function

In brain science, neural activity inevitably leads to the fluctuation of cerebral blood flow. Toward comprehensively understanding brain, it is necessary to develop an epidermal electrode that can concurrently monitor the brain’s electrical activity and hemodynamic activity. Here, we report an ultra-conductive and transparent epidermal electrode for simultaneous dual-mode assessment of brain function. The electrode can accurately and imperceivably detect electrophysiological signals and functional near-infrared spectroscopy (fNIRS) optical signals. It is fabricated by two monolayer graphene with confined poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) in between, namely GPG. Its extremely low sheet resistance (20.8 Ω/sq, 3727 S/cm, 129 nm) and high transmittance (∼80%) can be attributed to the more ordered alignment and dense packing of PEDOT due to the nano-confinement effect of bi-layer graphene. The strong π-π interaction between graphene and PEDOT:PSS results in the decreased stacking distance between PEDOT. Leveraging the excellent electrical property and ultrathin nature, this epidermal electrode is able to achieve low skin-electrode impedance and monitor various electrophysiological signals accurately and stably, even if the participant is in motion. Beneficial from the appropriate transparency, it can simultaneously record very weak EEG electrical signals and fNIRS optical signals, enabling dual-model brain activity analysis with high temporal and spatial resolution.

Using multi-modal neuroimaging to characterise social brain specialisation in infants.

The specialised regional functionality of the mature human cortex partly emerges through experience-dependent specialisation during early development. Our existing understanding of functional specialisation in the infant brain is based on evidence from unitary imaging modalities and has thus focused on isolated estimates of spatial or temporal selectivity of neural or haemodynamic activation, giving an incomplete picture. We speculate that functional specialisation will be underpinned by better coordinated haemodynamic and metabolic changes in a broadly orchestrated physiological response. To enable researchers to track this process through development, we develop new tools that allow the simultaneous measurement of coordinated neural activity (EEG), metabolic rate, and oxygenated blood supply (broadband near-infrared spectroscopy) in the awake infant. In 4- to 7-month-old infants, we use these new tools to show that social processing is accompanied by spatially and temporally specific increases in coupled activation in the temporal-parietal junction, a core hub region of the adult social brain. During non-social processing, coupled activation decreased in the same region, indicating specificity to social processing. Coupling was strongest with high-frequency brain activity (beta and gamma), consistent with the greater energetic requirements and more localised action of high-frequency brain activity. The development of simultaneous multimodal neural measures will enable future researchers to open new vistas in understanding functional specialisation of the brain.

Assessing the impact of preferred web app-based music-listening on pain processing at the central nervous level in older black adults with low back pain: An fNIRS study

BackgroundLow back pain (LBP) disproportionately affects older black adults, often leading to inadequate treatment due to clinician biases. Objective pain measures are imperative, and Functional Near-Infrared Spectroscopy (fNIRS) shows promise for pain detection. AimTo determine the impact of listening to home-based preferred web app-based music on underlying pain processing mechanisms at the central nervous level in older black adults aged ≥65 with LBP. MethodsTwenty older black adults with LBP listened to preferred music twice daily for four days using the MUSIC CARE® app. Neuroimaging data were collected using fNIRS. Data were transformed to changes in oxy-hemoglobin and deoxy-hemoglobin concentrations and analyzed. ResultsSignificant cortical activation pattern differences were observed between pre-and post-intervention scans, particularly in somatosensory regions. Post-intervention scans showed significantly reduced hemodynamic activities. ConclusionPreferred music listening has the potential to alleviate pain, and fNIRS emerges as a promising tool for exploring cortical-level pain-related neural circuits.

Functional network disorganization and cognitive decline following fractionated whole-brain radiation in mice

Cognitive dysfunction following radiotherapy (RT) is one of the most common complications associated with RT delivered to the brain, but the precise mechanisms behind this dysfunction are not well understood, and to date, there are no preventative measures or effective treatments. To improve patient outcomes, a better understanding of the effects of radiation on the brain’s functional systems is required. Functional magnetic resonance imaging (fMRI) has shown promise in this regard, however, compared to neural activity, hemodynamic measures of brain function are slow and indirect. Understanding how RT acutely and chronically affects functional brain organization requires more direct examination of temporally evolving neural dynamics as they relate to cerebral hemodynamics for bridging with human studies. In order to adequately study the underlying mechanisms of RT-induced cognitive dysfunction, the development of clinically mimetic RT protocols in animal models is needed. To address these challenges, we developed a fractionated whole-brain RT protocol (3Gy/day for 10 days) and applied longitudinal wide field optical imaging (WFOI) of neural and hemodynamic brain activity at 1, 2, and 3 months post RT. At each time point, mice were subject to repeated behavioral testing across a variety of sensorimotor and cognitive domains. Disruptions in cortical neuronal and hemodynamic activity observed 1 month post RT were significantly worsened by 3 months. While broad changes were observed in functional brain organization post RT, brain regions most impacted by RT occurred within those overlapping with the mouse default mode network and other association areas similar to prior reports in human subjects. Further, significant cognitive deficits were observed following tests of novel object investigation and responses to auditory and contextual cues after fear conditioning. Our results fill a much-needed gap in understanding the effects of whole-brain RT on systems level brain organization and how RT affects neuronal versus hemodynamic signaling in the cortex. Having established a clinically-relevant injury model, future studies can examine therapeutic interventions designed to reduce neuroinflammation-based injury following RT. Given the overlap of sequelae that occur following RT with and without chemotherapy, these tools can also be easily incorporated to examine chemotherapy-related cognitive impairment.

Integrating multimodal and multiscale connectivity blueprints of the human cerebral cortex in health and disease.

The brain is composed of disparate neural populations that communicate and interact with one another. Although fiber bundles, similarities in molecular architecture, and synchronized neural activity all reflect how brain regions potentially interact with one another, a comprehensive study of how all these interregional relationships jointly reflect brain structure and function remains missing. Here, we systematically integrate 7 multimodal, multiscale types of interregional similarity ("connectivity modes") derived from gene expression, neurotransmitter receptor density, cellular morphology, glucose metabolism, haemodynamic activity, and electrophysiology in humans. We first show that for all connectivity modes, feature similarity decreases with distance and increases when regions are structurally connected. Next, we show that connectivity modes exhibit unique and diverse connection patterns, hub profiles, spatial gradients, and modular organization. Throughout, we observe a consistent primacy of molecular connectivity modes-namely correlated gene expression and receptor similarity-that map onto multiple phenomena, including the rich club and patterns of abnormal cortical thickness across 13 neurological, psychiatric, and neurodevelopmental disorders. Finally, to construct a single multimodal wiring map of the human cortex, we fuse all 7 connectivity modes and show that the fused network maps onto major organizational features of the cortex including structural connectivity, intrinsic functional networks, and cytoarchitectonic classes. Altogether, this work contributes to the integrative study of interregional relationships in the human cerebral cortex.

Modulating Cortical Hemodynamic Activity in Parkinson's Disease Using Focal Transcranial Direct Current Stimulation: A Pilot Functional Near-infrared Spectroscopy Study.

Reduced thalamocortical facilitation of the motor cortex in PD leads to characteristic motor deficits such as bradykinesia. Recent research has highlighted improved motor function following tDCS, but a lack of neurophysiological evidence limits the progress of tDCS as an adjunctive therapy. Here, we tested the hypothesis that tDCS may modulate M1 hemodynamic activity in PD and healthy using functional near-infrared spectroscopy (fNIRS). In this randomized crossover experiment, fourteen PD and twelve healthy control participants attended three laboratory sessions and performed a regulated (3Hz) right index finger tapping task before and after receiving tDCS. On each visit, participants received either anodal, cathodal, or sham tDCS applied over M1. Hemodynamic activity of M1 was quantified using fNIRS. Significant task related activity was observed in M1 and the inferior parietal lobe in PD and healthy (p < 0.05). PD additionally recruited the dorsal premotor cortex. During tDCS, while at rest, anodal and cathodal tDCS significantly increased the oxygenated hemoglobin concentration of M1 compared to sham (t62 = 4.09 and t62 = 4.25, respectively). Task related hemodynamic activity was unchanged following any tDCS intervention (p > 0.05). Task related hemodynamic activity of M1 is not modulated by tDCS in PD or healthy. During tDCS, both anodal and cathodal stimulation cause a significant increase of M1 oxygenation, the clinical significance of which remains to be clarified.

Neurovascular coupling during auditory stimulation: event-related potentials and fNIRS hemodynamic

Intensity-dependent amplitude changes (IDAP) have been extensively studied using event-related potentials (ERPs) and have been linked to several psychiatric disorders. This study aims to explore the application of functional near-infrared spectroscopy (fNIRS) in IDAP paradigms, which related to ERPs could indicate the existence of neurovascular coupling. Thirty-three and thirty-one subjects participated in two experiments, respectively. The first experiment consisted of the presentation of three-tone intensities (77.9 dB, 84.5 dB, and 89.5 dB) lasting 500 ms, each type randomly presented 54 times, while the second experiment consisted of the presentation of five-tone intensities (70.9 dB, 77.9 dB, 84.5 dB, 89.5 dB, and 94.5 dB) in trains of 8 tones lasting 70 ms each tone, the trains were presented 20 times. EEG was used to measure ERP components: N1, P2, and N1–P2 peak-to-peak amplitude. fNIRS allowed the analysis of the hemodynamic activity in the auditory, visual, and prefrontal cortices. The results showed an increase in N1, P2, and N1–P2 peak-to-peak amplitude with auditory intensity. Similarly, oxyhemoglobin and deoxyhemoglobin concentrations showed amplitude increases and decreases, respectively, with auditory intensity in the auditory and prefrontal cortices. Spearman correlation analysis showed a relationship between the left auditory cortex with N1 amplitude, and the right dorsolateral cortex with P2 amplitude, specifically for deoxyhemoglobin concentrations. These findings suggest that there is a brain response to auditory intensity changes that can be obtained by EEG and fNIRS, supporting the neurovascular coupling process. Overall, this study enhances our understanding of fNIRS application in auditory paradigms and highlights its potential as a complementary technique to ERPs.

Invited Session IV: Studies of the visual cortex with sub-millimeter resolution: Three-photon imaging reveals the neural basis of fMRI across cortical layers.

V1 is ideally suited to study the spatial organization of neurovascular coupling at the level of synapses, neurons, individual blood vessels and laminar-resolution fMRI. This is because at least in layers 1 and 2/3 of V1, the functional micro-architecture for neurons, synapses and blood vessels has been determined using 2-photon imaging (Ohki et al 2005 Nature; Kara and Boyd 2009 Nature; O'Herron et al 2016 Nature). Hence, feature selectivity, e.g., orientation and direction selectivity of spiking, synaptic and hemodynamic activity in layer 2/3 is known. However, the micro-architecture of layer 4 neural activity (spiking and synaptic) along with individual blood vessel responses is unknown because conventional 2-photon imaging cannot access deeper cortical layers. The organizing principles of neural maps and the selectivity of hemodynamic responses is of paramount importance for laminar processing because the thalamic inputs arriving into layer 4 are untuned. 3-photon imaging triples the imaging depth compared to 2-photon imaging. Using this optical technique and high-resolution fMRI, we have determined the extent to which different types of neural (spiking, synaptic) and vascular signals (blood flow from individual vessels and fMRI voxels) are coupled across cortical layers in the cat V1. Our data show systematic changes in selectivity of hemodynamic signals across cortical layers that have clear underpinnings in neural circuitry and the propagation of hemodynamic signals.

Neural Correlates of Object-Extracted Relative Clause Processing Across English and Chinese

Abstract Are the brain bases of language comprehension the same across all human languages, or do these bases vary in a way that corresponds to differences in linguistic typology? English and Mandarin Chinese attest such a typological difference in the domain of relative clauses. Using functional magnetic resonance imaging with English and Chinese participants, who listened to the same translation-equivalent story, we analyzed neuroimages time aligned to object-extracted relative clauses in both languages. In a general linear model analysis of these naturalistic data, comprehension was selectively associated with increased hemodynamic activity in left posterior temporal lobe, angular gyrus, inferior frontal gyrus, precuneus, and posterior cingulate cortex in both languages. This result suggests the processing of object-extracted relative clauses is subserved by a common collection of brain regions, regardless of typology. However, there were also regions that were activated uniquely in our Chinese participants albeit not to a significantly greater degree. These were in the temporal lobe. These Chinese-specific results could reflect structural ambiguity-resolution work that must be done in Chinese but not English object-extracted relative clauses.

Friction and neuroimaging of active and passive tactile touch

Two types of exploratory touch including active sliding and passive sliding are usually encountered in the daily life. The friction behavior of the human finger against the surface of objects is important in tactile perception. The neural mechanisms correlating to tribological behavior are not fully understood. This study investigated the tactile response of active and passive finger friction characterized with functional near-infrared spectroscopy (fNIRS). The friction test and fNIRS test were performed simultaneously using the tactile stimulus of polytetrafluoroethylene (PTFE) specimens. Results showed that the sliding modes did not obviously influence the friction property of skin. While three cortex regions were activated in the prefrontal cortex (PFC), showing a higher activation level of passive sliding. This revealed that the tribological performance was not a simple parameter to affect tactile perception, and the difference in cortical hemodynamic activity of active and passive touch was also recognised. The movement-related blood flow changes revealed the role of PFC in integrating tactile sensation although there was no estimation task on roughness perception.

Correlation between cerebral hemodynamic functional near-infrared spectroscopy and positron emission tomography for assessing mild cognitive impairment and Alzheimer's disease: An exploratory study.

This study was performed to investigate the usefulness of functional near-infrared spectroscopy (fNIRS) by conducting a comparative analysis of hemodynamic activation detected by fNIRS and positron emission tomography (PET) and magnetic resonance imaging (MRI) in patients with mild cognitive impairment (MCI) and Alzheimer's disease (AD). Participants were divided into four groups: the subjective memory impairment (SMI), amnestic MCI (aMCI), non-amnestic MCI (naMCI), and AD groups. We recorded the hemodynamic response during the semantic verbal fluency task (SVFT) using a commercial wireless continuous-wave NIRS system. The correlation between the parameters of the neuroimaging assessments among the groups was analyzed. Region of interest-based comparisons showed that the four groups had significantly different hemodynamic responses during SVFT in the bilateral dorsolateral prefrontal cortex (DLPFC). The linear mixed effect model result indicates that the mean ΔHbO2 from the bilateral DLPFC regions showed a significant positive correlation to the overall FDG-PET after controlling for age and group differences in the fNIRS signals. Amyloid PET signals tended to better differentiate the AD group from other groups, and fNIRS signals tended to better differentiate the SMI group from other groups. In addition, a comparison between the group pairs revealed a mirrored pattern between the hippocampal volume and hemodynamic response in the DLPFC. The hemodynamic response detected by fNIRS showed a significant correlation with metabolic and anatomical changes associated with disease progression. Therefore, fNIRS may be considered as a screening tool to predict the hemodynamic and metabolic statuses of the brain in patients with MCI and AD.

First Records of Heartbeats via ECG in a Stingless Bee, Melipona flavolineata (Apidae, Meliponini), during Contention Stress Using Isoflurane as an Anesthetic.

The hemodynamic activity of Melipona flavolineata workers was evaluated during restraint stress for a period of 30 min. The observed parameters were power variation in the elapsed time, and subsequently, six periods of one second were divided and called A, B, C, D, E and F; in each period, the electrocardiographic parameters were evaluated: spike frequency, amplitude, spike intervals and spike duration. The experiment was carried out with eight worker bees of M. flavolineata, for which electrodes of a nickel-chromium alloy were made. The bees were previously anesthetized with isoflurane and properly contained and fixed in a base for stereotaxis in which the electrode was implanted. All these procedures were performed inside a Faraday cage. The results showed power oscillations during the recording, with the highest energy level being between 300 and 600 s. Spike frequency, spike amplitude, interval between spikes and spike duration parameters underwent changes during the restraint stress period. Thus, the cardiac activity of M. flavolineata can be used as a biomarker and can be used to clarify physiological issues or alterations caused by toxic agents and indicate risk factors for these animals.

Premotor function in interpersonal bimanual coordination: Neural responses to varying frequencies and spatio–temporal relationships

BackgroundInterpersonal movement coordination is an important aspect of daily life. Behavioral studies have found that rhythmic bimanual coordination of movement is mainly influenced by two factors, spatio–temporal relationship and frequency of movements. How these factors affect action coordination at the neural level needs further exploration. The current study used a factor design to investigate the brain basis of movement coordination under various spatiotemporal relationships and frequencies, as well as their intricate interaction. MethodsParticipants were asked to perform symmetric or alternating hand movements under conditions of different spatio–temporal relationships (symmetric, alternating) and frequencies. A multi–channel, continuous wave, functional near–infrared spectral (fNIRS) imaging instrument was used to monitor hemodynamic activity while 16 pairs of volunteers performed the task. ResultsBehaviorally, as indexed by phase locking value, movements were more stable in symmetric mode than in alternate mode. With increasing frequency, symmetric mode became more unstable; in contrast, alternating mode became more stable at higher frequencies, suggesting phase transition. Activation in brain regions of interest was much stronger in symmetric mode as compared with alternate mode. In alternate mode, but not symmetric mode, [HbO] varied with frequency. ConclusionInterpersonal bimanual coordination involves activity in premotor areas (premotor cortex, supplementary motor area, and frontal eye fields). More oxygen is consumed in these regions in alternating mode than in symmetric mode.

Endogenous Opioid Release After Orgasm in Man: A Combined PET/Functional MRI Study.

The endogenous μ-opioid receptor (MOR) system plays a key role in the mammalian reward circuit. Human and animal experiments suggest the involvement of MORs in human sexual pleasure, yet this hypothesis currently lacks invivo support. Methods: We used PET with the radioligand [11C]carfentanil, which has high affinity for MORs, to quantify endogenous opioid release after orgasm in man. Participants were scanned once immediately after orgasm and once in a baseline state. Hemodynamic activity was measured with functional MRI during penile stimulation. Results: The PET data revealed significant opioid release in the hippocampus. Hemodynamic activity in the somatosensory and motor cortices and in the hippocampus and thalamus increased during penile stimulation, and thalamic activation was linearly dependent on self-reported sexual arousal. Conclusion: Our data show that endogenous opioidergic activation in the medial temporal lobe is centrally involved in sexual arousal, and this circuit may be implicated in orgasmic disorders.

An fNIRS investigation of novel expressed emotion stimulations in schizophrenia

Living in high expressed emotion (EE) environments tends to increase the relapse rate in schizophrenia (SZ). At present, the neural substrates responsible for high EE in SZ remain poorly understood. Functional near-infrared spectroscopy (fNIRS) may be of great use to quantitatively assess cortical hemodynamics and elucidate the pathophysiology of psychiatric disorders. In this study, we designed novel low- (positivity and warmth) and high-EE (criticism, negative emotion, and hostility) stimulations, in the form of audio, to investigate cortical hemodynamics. We used fNIRS to measure hemodynamic signals while participants listened to the recorded audio. Healthy controls (HCs, n=42) showed increased hemodynamic activation in the major language centers across EE stimulations, with stronger activation in Wernicke’s area during the processing of negative emotional language. Compared to HCs, people with SZ (n=41) exhibited smaller hemodynamic activation in the major language centers across EE stimulations. In addition, people with SZ showed weaker or insignificant hemodynamic deactivation in the medial prefrontal cortex. Notably, hemodynamic activation in SZ was found to be negatively correlated with the negative syndrome scale score at high EE. Our findings suggest that the neural mechanisms in SZ are altered and disrupted, especially during negative emotional language processing. This supports the feasibility of using the designed EE stimulations to assess people who are vulnerable to high-EE environments, such as SZ. Furthermore, our findings provide preliminary evidence for future research on functional neuroimaging biomarkers for people with psychiatric disorders.

626-P: Integrated Approach of Yoga Therapy (IAYT) Improves Cerebrovascular Functions and Prefrontal Hemodynamic Activities Related to Cognition in Type 2 Diabetes

The present study aimed to assess the integrated approach of yoga therapy (IAYT) effect on cerebrovascular reactivity in middle cerebral artery (MCA), prefrontal cortex (PFC) oxygenation and cognitive functions in patients with T2DM. Method: 75 patients were randomized to the IAYT group [n=38; 07 female; mean age 52.95 (8.20) years] and the waitlist control group [n=37; 06female; mean age (SD) 49.62 (10.94) years]. The cerebral blood flow and prefrontal hemodynamic activities were assessed using transcranial doppler and functional near-infrared spectroscopy, respectively, during resting and cognitive performance. IAYT group participants received 3 months of intervention and assessments were done at baseline (0-week), mid (after 6-week), and post (after 12-week). Results: After a 12-week intervention, participants of the yoga group showed improved accuracy and reaction time in a 2-back condition of the working memory task, and the scores of the Corsi Block Tapping task. Further, cerebrovascular changes were observed in the middle cerebral artery, which showed increased peak systolic velocity, mean blood flow velocity, end-diastolic velocity, and breath-holding index after 12-week yoga practice. The oxygenation was also higher at dorsolateral, dorsomedial, and ventromedial and orbitofrontal PFC in the 12th week of the yoga practitioners group compared to the control group. Moreover, during 2-back working memory task, yoga group participants demonstrated increased oxygenation at dorsolateral PFC compared to pre and higher oxygenation at dorsolateral, ventrolateral, ventromedial and orbitofrontal PFC compared to control group. Conclusion: The results suggest that IAYT practice may improve cognitive functions by improving cerebral blood flow through the middle cerebral artery and hemodynamic activities in the prefrontal regions in patients with T2DM. Disclosure D.Singh: None. C.Kaligal: None. V.M: None. A.Kanthi: None. Funding Ministry of Ayush, Government of India (Z.280152092015-HPC(EMR)-AYUSH)