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Intergenerational Stress ...
Forum: General Neuroscience talk
Last Post: BioRxiv
04-13-2021, 04:47 AM
» Replies: 0
» Views: 14
Weak Task Synchronization...
Forum: General Neuroscience talk
Last Post: BioRxiv
04-13-2021, 04:47 AM
» Replies: 0
» Views: 11
Proprioceptive imprecisio...
Forum: General Neuroscience talk
Last Post: BioRxiv
04-13-2021, 04:47 AM
» Replies: 0
» Views: 8
A unified model of the ta...
Forum: General Neuroscience talk
Last Post: BioRxiv
04-13-2021, 04:47 AM
» Replies: 0
» Views: 8
BRAIN-BASED AUTHENTICATIO...
Forum: General Neuroscience talk
Last Post: BioRxiv
04-13-2021, 04:47 AM
» Replies: 0
» Views: 12
Online Closed-Loop Real-T...
Forum: General Neuroscience talk
Last Post: BioRxiv
04-13-2021, 04:47 AM
» Replies: 0
» Views: 10
Respiratory dysfunctions ...
Forum: General Neuroscience talk
Last Post: BioRxiv
04-13-2021, 04:47 AM
» Replies: 0
» Views: 32
Intergenerational Stress ...
Forum: General Neuroscience talk
Last Post: BioRxiv
04-13-2021, 02:11 AM
» Replies: 0
» Views: 16
Subjective confidence ref...
Forum: General Neuroscience talk
Last Post: BioRxiv
04-13-2021, 02:11 AM
» Replies: 0
» Views: 12
State dependence of neura...
Forum: General Neuroscience talk
Last Post: BioRxiv
04-13-2021, 02:11 AM
» Replies: 0
» Views: 12

 
  Intergenerational Stress Transmission is Associated with Brain Metabotranscriptome
Posted by: BioRxiv - 04-13-2021, 04:47 AM - Forum: General Neuroscience talk - No Replies

Intergenerational Stress Transmission is Associated with Brain Metabotranscriptome


Intergenerational stress increases lifetime susceptibility to depression and other psychiatric disorders. Whether intergenerational stress transmission is a consequence of in utero neurodevelopmental disruptions vs early-life mother-infant interaction is largely unknown. Here, we demonstrated that exposure to traumatic stress in mice during pregnancy, through predator scent exposure, induces in the offspring social deficits and depressive-like behavior. We found, through cross-fostering experiments, that raising of normal pups by traumatized mothers produced a similar behavioral phenotype to that induced in pups raised by their biological traumatized mothers. Good caregiving (by non-traumatized mothers), however, did not completely protect against the prenatal trauma-induced behavioral deficits. These findings support a two-hit stress mechanism of both in utero and early-life parenting (poor caregiving by the traumatized mothers) environments. Associated with the behavioral deficits, we found profound changes in brain metabolomics and transcriptomic (metabotranscriptome). Striking increases in the mitochondrial hypoxia marker and epigenetic modifier 2-hydroxyglutaric acid, in the brains of neonatal and adult pups whose mothers were exposed to stress during pregnancy, indicated mitochondrial metabolism dysfunctions and epigenetic mechanisms. Bioinformatic analyses revealed mechanisms involving stress- and hypoxia-response metabolic pathways in the brains of the neonatal mice, which appear to lead to long-lasting alterations in mitochondrial-energy metabolism, and epigenetic processes pertaining to DNA and chromatin modifications. Most strikingly, we demonstrated that an early pharmacological intervention that can correct mitochondria metabolism - lipid metabolism and epigenetic modifications with acetyl-L-carnitine (ALCAR) supplementation - produces long-lasting protection against the behavioral deficits associated with intergenerational transmission of traumatic stress.



O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=129 SRC="FIGDIR/small/438868v1_ufig1.gif" ALT="Figure 1">
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[email protected]@[email protected][email protected]_HPS_FORMAT_FIGEXP M_FIG C_FIG



http://biorxiv.org/cgi/content/short/202...68v1?rss=1

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  Weak Task Synchronization of Default Mode Network in Task Based Paradigms
Posted by: BioRxiv - 04-13-2021, 04:47 AM - Forum: General Neuroscience talk - No Replies

Weak Task Synchronization of Default Mode Network in Task Based Paradigms


Default Mode Network (DMN) has been called a "task-negative" network which deactivates during engaging extrinsic tasks. But the behavior is more nuanced. We analyse the DMN during three different tasks (visual, affect and language; n=54) and find inter trial variability which gets amiss when analysed using General Linear Model (GLM). The region also shows significant across subjects variations which limits the use of Inter Subject Correlation (ISC) method to detect correlated deactivations during the task. We introduce Temporal Synchronization Analysis (TSA), a family of methods that can help detect inter-trial (IT-TSA) and inter-subject (IS-TSA) synchronization across the brain. We find that DMN is weakly synchronized across trials and subjects, challenging the notion of task negative behavior. Our study suggests the role of DMN as an active component associated with self-referential, autobiographical processes which are deactivated differentially and non linearly across trials and subjects in the presence of extrinsic processes.



http://biorxiv.org/cgi/content/short/202...06v1?rss=1

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  Proprioceptive imprecision in Ehlers-Danlos Syndrome does not affect the extent of
Posted by: BioRxiv - 04-13-2021, 04:47 AM - Forum: General Neuroscience talk - No Replies

Proprioceptive imprecision in Ehlers-Danlos Syndrome does not affect the extent of


Purpose: To explore the effect of joint hypermobility on acuity, and plasticity, of hand proprioception. Materials and Methods: We compared proprioceptive acuity between EDS patients and controls. We then measured any changes in their estimate of hand position after participants adapted their reaches in response to altered visual feedback of their hand. The Beighton Scale was used to quantify the magnitude of joint hypermobility. Results: There were no differences between the groups in the accuracy of estimates of hand location, nor in the visually-induced changes in hand location. However, EDS patients' estimates were less precise when based purely on proprioception and could be moderately predicted by Beighton score. Conclusions: EDS patients are less precise at estimating their hand's location when only afferent information is available, but the presence of efferent signalling may reduce this imprecision. Those who are more hypermobile are more likely to be imprecise. This deficit likely has peripheral origins since we found no differences in the extent of sensorimotor plasticity.



http://biorxiv.org/cgi/content/short/202...51v1?rss=1

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  A unified model of the task-evoked pupil response
Posted by: BioRxiv - 04-13-2021, 04:47 AM - Forum: General Neuroscience talk - No Replies

A unified model of the task-evoked pupil response


The pupil dilates and re-constricts following task events. It is popular to model this task-evoked pupil response as a linear transformation of event-locked impulses, the amplitudes of which are used as estimates of arousal. We show that this model is incorrect, and we propose an alternative model based on the physiological finding that a common neural input drives saccades and pupil size. The estimates of arousal from our model agreed with key predictions: arousal scaled with task difficulty and behavioral performance but was invariant to trial duration. Moreover, the model offers a unified explanation for a wide range of phenomena: entrainment of pupil size and saccade occurrence to task timing, modulation of pupil response amplitude and noise with task difficulty, reaction-time dependent modulation of pupil response timing and amplitude, a constrictory pupil response time-locked to saccades, and task-dependent distortion of this saccade-locked pupil response.



http://biorxiv.org/cgi/content/short/202...31v1?rss=1

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  BRAIN-BASED AUTHENTICATION: TOWARDS A SCALABLE, COMMERCIAL GRADE SOLUTION USING NO
Posted by: BioRxiv - 04-13-2021, 04:47 AM - Forum: General Neuroscience talk - No Replies

BRAIN-BASED AUTHENTICATION: TOWARDS A SCALABLE, COMMERCIAL GRADE SOLUTION USING NO


In this study we report on a field test where we asked if it is feasible to deliver a scalable, commercial-grade solution for brain-based authentication currently given available head wearables. Sixty-two (62) participants living across the United States in autumn 2020 completed four (4) at-home sessions over a single (1) week. In each session there were six (6) authentication events consisting of rapid presentation of images (10Hz) that participants watched for 10 seconds while recording their brain signal with an off-the-shelf brain signal measuring headband. The non-stationary nature of the brain signal, and the fact that the signal results from a superposition of hundreds of simultaneous processes in the brain that respond to context makes the data unique in time, unrepeatable, and unpredictable. Even when a participant watched identical stimuli, we find no two periods of time to be alike (Fig. 4B) and furthermore, no two combinations of time periods are alike. Differences within people (intra-) and across people (inter- participant) from session to session were found to be significant, however stable processes do appear to be underlying the signal complexity and non-stationarity. We show a simplified brain-based authentication system that captures distinguishable information with reliable, commercial-grade performance from participants at their own homes. We conclude that noninvasively measured brain signals are an ideal candidate for biometric authentication, especially for head wearables such as headphones and AR/VR devices.



http://biorxiv.org/cgi/content/short/202...44v1?rss=1

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  Online Closed-Loop Real-Time tES-fMRI for Brain Modulation: Feasibility, Noise/Saf
Posted by: BioRxiv - 04-13-2021, 04:47 AM - Forum: General Neuroscience talk - No Replies

Online Closed-Loop Real-Time tES-fMRI for Brain Modulation: Feasibility, Noise/Saf


Recent studies suggest that transcranial electrical stimulation (tES) can be performed during functional magnetic resonance imaging (fMRI). The novel approach of using concurrent tES-fMRI to modulate and measure targeted brain activity/connectivity may provide unique insights into the causal interactions between the brain neural responses and psychiatric/neurologic signs and symptoms, and importantly, guide the development of new treatments. However, tES stimulation parameters to optimally influence the underlying brain activity in health and disorder may vary with respect to phase, frequency, intensity, and electrode's montage. Here, we delineate how a closed-loop tES-fMRI study of frontoparietal network modulation can be designed and performed. We also discuss the challenges of running a concurrent tES-fMRI, describing how we can distinguish clinically meaningful physiological changes caused by tES from tES-related artifacts. There is a large methodological parameter space including electrode types, electrolytes, electrode montages, concurrent tES-fMRI hardware, online fMRI processing pipelines and closed-loop optimization algorithms that should be carefully selected for closed-loop tES-fMRI brain modulation. We also provide technical details on how safety and quality of tES-fMRI settings can be tested, and how these settings can be monitored during the study to ensure they do not exceed safety standards. The initial results of feasibility and applicability of closed-loop tES-fMRI are reported and potential hypotheses for the outcomes are discussed.



http://biorxiv.org/cgi/content/short/202...68v1?rss=1

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  Respiratory dysfunctions in two rodent models of chronic epilepsy and acute seizur
Posted by: BioRxiv - 04-13-2021, 04:47 AM - Forum: General Neuroscience talk - No Replies

Respiratory dysfunctions in two rodent models of chronic epilepsy and acute seizur


Patients with drug-resistant epilepsy can experience respiratory alterations notably during seizures. The mechanisms underlying this long-term alteration of respiratory function remain unclear. This study aimed at determining in rats whether epilepsy is associated with alterations of both the respiratory function and brainstem serotonin (5-HT) system. Epilepsy was triggered by pilocarpine-induced status epilepticus in rats. 30-50% of epileptic (EPI) rats exhibited sharp decrease of oxygen consumption (SDOC), low metabolic rate of oxygen and slow regular ventilation; these rats were called EPI/SDOC+ rats. These alterations were only detected in rats with chronic epilepsy, independent of behavioral seizures, persisted over the time, and were not associated with death. In these rats, 5-HT fiber density in the nucleus tractus solitarius was below that of control and EPI/SDOC- rats. Both EPI/SDOC+ rats and DBA/2 mice presenting with fatal respiratory arrest following an audiogenic-induced seizure, a model of sudden and expected death in epilepsy, had increased transcript levels of tryptophan hydroxylase 2 (p<0.001 for both strains) and 5-HT presynaptic transporter (rats: p=0.003; mice: p=0.001). Thus, our data support that 5-HT alterations are associated with chronic and acute epilepsy-related respiratory dysfunctions.



http://biorxiv.org/cgi/content/short/202...21v1?rss=1

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  Intergenerational Stress Transmission is Associated with Brain Metabotranscriptome
Posted by: BioRxiv - 04-13-2021, 02:11 AM - Forum: General Neuroscience talk - No Replies

Intergenerational Stress Transmission is Associated with Brain Metabotranscriptome


Intergenerational stress increases lifetime susceptibility to depression and other psychiatric disorders. Whether intergenerational stress transmission is a consequence of in utero neurodevelopmental disruptions vs early-life mother-infant interaction is largely unknown. Here, we demonstrated that exposure to traumatic stress in mice during pregnancy, through predator scent exposure, induces in the offspring social deficits and depressive-like behavior. We found, through cross-fostering experiments, that raising of normal pups by traumatized mothers produced a similar behavioral phenotype to that induced in pups raised by their biological traumatized mothers. Good caregiving (by non-traumatized mothers), however, did not completely protect against the prenatal trauma-induced behavioral deficits. These findings support a two-hit stress mechanism of both in utero and early-life parenting (poor caregiving by the traumatized mothers) environments. Associated with the behavioral deficits, we found profound changes in brain metabolomics and transcriptomic (metabotranscriptome). Striking increases in the mitochondrial hypoxia marker and epigenetic modifier 2-hydroxyglutaric acid, in the brains of neonatal and adult pups whose mothers were exposed to stress during pregnancy, indicated mitochondrial metabolism dysfunctions and epigenetic mechanisms. Bioinformatic analyses revealed mechanisms involving stress- and hypoxia-response metabolic pathways in the brains of the neonatal mice, which appear to lead to long-lasting alterations in mitochondrial-energy metabolism, and epigenetic processes pertaining to DNA and chromatin modifications. Most strikingly, we demonstrated that an early pharmacological intervention that can correct mitochondria metabolism - lipid metabolism and epigenetic modifications with acetyl-L-carnitine (ALCAR) supplementation - produces long-lasting protection against the behavioral deficits associated with intergenerational transmission of traumatic stress.



O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=129 SRC="FIGDIR/small/438868v1_ufig1.gif" ALT="Figure 1">
View larger version (40K):
[email protected]@856638org.highwi[email protected]@68b485_HPS_FORMAT_FIGEXP M_FIG C_FIG



http://biorxiv.org/cgi/content/short/202...68v1?rss=1

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  Subjective confidence reflects representation of Bayesian probability in cortex
Posted by: BioRxiv - 04-13-2021, 02:11 AM - Forum: General Neuroscience talk - No Replies

Subjective confidence reflects representation of Bayesian probability in cortex


What gives rise to the human sense of confidence? Here, we tested the Bayesian hypothesis that confidence is based on a probability distribution represented in neural population activity. We implemented several computational models of confidence, and tested their predictions using psychophysics and fMRI. Using a generative model-based fMRI decoding approach, we extracted probability distributions from neural population activity in human visual cortex. We found that subjective confidence tracks the shape of the decoded distribution. That is, when sensory evidence was more precise, as indicated by the decoded distribution, observers reported higher levels of confidence. We furthermore found that neural activity in the insula, anterior cingulate, and prefrontal cortex was linked to both the shape of the decoded distribution and reported confidence, in ways consistent with the Bayesian model. Altogether, our findings support recent statistical theories of confidence and suggest that probabilistic information guides the computation of ones sense of confidence.



http://biorxiv.org/cgi/content/short/202...72v1?rss=1

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  State dependence of neural networks on past history and stimulus presentation in C
Posted by: BioRxiv - 04-13-2021, 02:11 AM - Forum: General Neuroscience talk - No Replies

State dependence of neural networks on past history and stimulus presentation in C


Neurons cooperate and interact with one another to generate behavior. While individual neurons and their ensembles are often probed in isolation, very little is known about their relationships on a global scale. Here, we define six groups of neurons with interactions that encode and process food stimulus responses in Caenorhabditis elegans. Using brain-wide calcium imaging in restrained animals, we categorized active neurons into either: sensory (On or Off) or motor (forward, backward, dorsal or ventral turn) neuron groups. Next, we show that stimulus onset rapidly shifts activity from backward to forward motor neuron groups, while prolonged stimulus removal is required to initiate converse activity. Finally, we use a gated multinomial logistic regression model to understand how stimulus processing depends on network state. This study shows how neural activity is coordinated across a network to generate global dynamics that drive behavior.



http://biorxiv.org/cgi/content/short/202...42v1?rss=1

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