Assessment of the Social Dynamics of Xylazine-Involved Fatal Overdoses: A Network Analysis of the Spread of the Flesh-Eating “Zombie Drug”

Published: Jan. 1, 2025

Language: Английский

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Unraveling Multiregional Neural Patterns during Consciousness Transition Using Flexible Microelectrode Arrays Integrated with Neuropixels Chips

Nano Letters, Journal Year: 2025, Volume and Issue: unknown

Published: May 18, 2025

Consciousness transitions, including awakening from anesthesia or falling asleep, involve complex neural dynamics across multiple brain regions. Understanding these transitions requires simultaneous and stable monitoring of large-scale activity in freely moving animals. Here, a flexible microelectrode array system (FlexiPixels probe) is demonstrated that integrates multishank with Neuropixels chips. This lightweight FlexiPixels probe enables long-term signal recording regions rats tracking neuronal activities during consciousness to wakefulness subsequent sleep states. Distinct state-dependent firing patterns emerge different types. CA1 neurons show similar sleep, while DG exhibit unique sensitivity. These findings demonstrate FlexiPixels' capabilities for multiregion animals potential unravel region-specific signatures studies.

Language: Английский

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Neural Correlates of Consciousness

Springer eBooks, Journal Year: 2023, Volume and Issue: unknown, P. 1 - 15

Published: Jan. 1, 2023

Language: Английский

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Spine dynamics of PSD-95-deficient neurons in the visual cortex link silent synapses to structural cortical plasticity

Proceedings of the National Academy of Sciences, Journal Year: 2021, Volume and Issue: 118(10)

Published: March 1, 2021

Significance During critical periods, restricted time windows in early brain development, cortical neural circuits get refined an experience-dependent manner. Postsynaptic density protein-95 (PSD-95)-dependent maturation of silent glutamatergic synapses onto principal neurons is required for the termination period ocular dominance plasticity (ODP) primary visual cortex (V1) mice. Using chronic vivo two-photon imaging dendritic spine dynamics V1 awake mice, here we show that adult PSD-95-deficient display increased elimination after a brief monocular deprivation, structural hallmark juvenile ODP. Thus, both functional and hallmarks so PSD-95-dependent synapse stabilization correlated with closure.

Language: Английский

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Assessing brain state and anesthesia level with two-photon calcium signals

Scientific Reports, Journal Year: 2023, Volume and Issue: 13(1)

Published: Feb. 23, 2023

Abstract Brain states, such as wake, sleep, or different depths of anesthesia are usually assessed using electrophysiological techniques, the local field potential (LFP) electroencephalogram (EEG), which ideal signals for detecting activity patterns asynchronous oscillatory activities. However, it is technically challenging to have these types measures during calcium imaging recordings two-photon wide-field techniques. Here, simultaneous and LFP measurements, we demonstrate that despite slower dynamics signal, there a high correlation between taken from neuropil outside neuronal somata. Moreover, find signal be systematically delayed use model show delay two due physical distance recording sites. These results suggest alone can used detect slow oscillations ultimately assess brain state level anesthesia.

Language: Английский

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Neural Ensemble Fragmentation in the AnesthetizedDrosophilaBrain

Journal of Neuroscience, Journal Year: 2023, Volume and Issue: 43(14), P. 2537 - 2551

Published: March 3, 2023

General anesthetics cause a profound loss of behavioral responsiveness in all animals. In mammals, general anesthesia is induced part by the potentiation endogenous sleep-promoting circuits, although "deep" understood to be more similar coma (Brown et al., 2011). Surgically relevant concentrations anesthetics, such as isoflurane and propofol, have been shown impair neural connectivity across mammalian brain (Mashour Hudetz, 2017; Yang 2021), which presents one explanation why animals become largely unresponsive when exposed these drugs. It remains unclear whether affect dynamics similarly animal brains, or simpler animals, insects, even display levels that could disrupted Here, we used whole-brain calcium imaging behaving female

Language: Английский

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In VivoCalcium Imaging of CA3 Pyramidal Neuron Populations in Adult Mouse Hippocampus

eNeuro, Journal Year: 2021, Volume and Issue: 8(4), P. ENEURO.0023 - 21.2021

Published: July 1, 2021

Abstract Neuronal population activity in the hippocampal CA3 subfield is implicated cognitive brain functions such as memory processing and spatial navigation. However, because of its deep location brain, area has been difficult to target with modern calcium imaging approaches. Here, we achieved chronic two-photon pyramidal neurons red fluorescent indicator R-CaMP1.07 anesthetized awake mice. We characterize neuronal at both single-cell level assess stability across multiple days. During anesthesia wakefulness, nearly all displayed transients. Most transients were consistent a high incidence bursts action potentials (APs), based on calibration measurements using simultaneous juxtacellular recordings imaging. In mice, found state-dependent differences striking large prolonged during locomotion. estimate that trains >30 APs over 3 s underlie these salient events. Their abundance particular subsets was relatively stable At level, co-activity within network above chance co-active neuron pairs maintained their correlated Our results corroborate notion spatiotemporal patterns recurrent demonstrate least some features activity, namely cell likelihood engage are

Language: Английский

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Developmental increase of inhibition drives decorrelation of neural activity

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2021, Volume and Issue: unknown

Published: July 6, 2021

Abstract Throughout development, the brain transits from early highly synchronous activity patterns to a mature state with sparse and decorrelated neural activity, yet mechanisms underlying this process are unknown. The developmental transition has important functional consequences, as latter allows for more efficient storage, retrieval processing of information. Here, we show that, in mouse medial prefrontal cortex (mPFC), during first two postnatal weeks decorrelates following specific spatial patterns. This is accompanied by concomitant tilting excitation/inhibition (E-I) ratio towards inhibition. Using optogenetic manipulations network modeling, that phenomena mechanistically linked, relative increase inhibition drives decorrelation activity. Accordingly, models neurodevelopmental disorders, subtle alterations E-I associated impairments correlational structure spike trains. Finally, capitalizing on EEG data newborn babies, an analogous takes place also human brain. Thus, changes control (de)correlation and, these means, its imbalance might contribute pathogenesis disorders.

Language: Английский

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Centripetal integration of past events by hippocampal astrocytes and its regulation by the locus coeruleus

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2022, Volume and Issue: unknown

Published: Aug. 17, 2022

Abstract An essential feature of neurons is their ability to centrally integrate information from dendrites. The activity astrocytes, in contrast, has been described as mostly uncoordinated across cellular compartments without clear central integration. Here, we describe conditional centripetal integration a principle how astrocytes calcium signals distal processes induce somatic activation. We found mouse hippocampus that global astrocytic activity, recorded with population imaging, well explained leaky past neuronal and behavioral events on timescale seconds. Salient events, indicated by pupil dilations, facilitated propagation the soma this slow timescale. Centripetal was reproduced optogenetic activation locus coeruleus, key regulator arousal, reduced pharmacological inhibition α1-adrenergic receptors. Together, our results establish computational units brain slowly conditionally activate somata upon behaviorally relevant events.

Language: Английский

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The effects of acute Methylene Blue administration on cerebral blood flow and metabolism in humans and rats

Journal of Cerebral Blood Flow & Metabolism, Journal Year: 2023, Volume and Issue: 43(2_suppl), P. 95 - 105

Published: Feb. 21, 2023

Methylene Blue (MB) is a brain-penetrating drug with putative neuroprotective, antioxidant and metabolic enhancing effects. In vitro studies suggest that MB enhances mitochondrial complexes activity. However, no study has directly assessed the effects of in human brain. We used vivo neuroimaging to measure effect on cerebral blood flow (CBF) brain metabolism humans rats. Two doses (0.5 1 mg/kg humans; 2 4 rats; iv) induced reductions global (F(1.74, 12.17)5.82, p = 0.02) rats (F(1,5)26.04, 0.0038). Human rate oxygen (CMRO2) was also significantly reduced (F(1.26, 8.84)8.01, 0.016), as rat glucose (CMRglu) (t 2.6(16) 0.018). This contrary our hypothesis will increase CBF energy metrics. Nevertheless, results were reproducible across species dose dependent. One possible explanation concentrations used, although clinically relevant, reflect MB's hormetic effects, i.e., higher produce inhibitory rather than augmentation metabolism. Additionally, here we healthy volunteers normal where ability enhance might be limited.

Language: Английский

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