Revisiting the neurovascular unit

Nature Neuroscience, Год журнала: 2021, Номер 24(9), С. 1198 - 1209

Опубликована: Авг. 5, 2021

Язык: Английский

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Fluid transport in the brain

Physiological Reviews, Год журнала: 2021, Номер 102(2), С. 1025 - 1151

Опубликована: Май 5, 2021

The brain harbors a unique ability to, figuratively speaking, shift its gears. During wakefulness, the is geared fully toward processing information and behaving, while homeostatic functions predominate during sleep. blood-brain barrier establishes stable environment that optimal for neuronal function, yet imposes physiological problem; transcapillary filtration forms extracellular fluid in other organs reduced to minimum brain. Consequently, depends on special [the cerebrospinal (CSF)] flushed into along perivascular spaces created by astrocytic vascular endfeet. We describe this pathway, coined term glymphatic system, based dependency endfeet their adluminal expression of aquaporin-4 water channels facing CSF-filled spaces. Glymphatic clearance potentially harmful metabolic or protein waste products, such as amyloid-β, primarily active sleep, when drivers, cardiac cycle, respiration, slow vasomotion, together efficiently propel CSF inflow periarterial brain's space contains an abundance proteoglycans hyaluronan, which provide low-resistance hydraulic conduit rapidly can expand shrink sleep-wake cycle. system brain, meets requisites maintain homeostasis similar peripheral organs, considering blood-brain-barrier paths formation egress CSF.

Язык: Английский

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Neurovascular coupling: motive unknown

Trends in Neurosciences, Год журнала: 2022, Номер 45(11), С. 809 - 819

Опубликована: Авг. 19, 2022

Язык: Английский

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Intrinsic macroscale oscillatory modes driving long range functional connectivity in female rat brains detected by ultrafast fMRI

Nature Communications, Год журнала: 2023, Номер 14(1)

Опубликована: Фев. 6, 2023

Abstract Spontaneous fluctuations in functional magnetic resonance imaging (fMRI) signals correlate across distant brain areas, shaping functionally relevant intrinsic networks. However, the generative mechanism of fMRI signal correlations, and particular link with locally-detected ultra-slow oscillations, are not fully understood. To investigate this link, we record ultrafast ultrahigh field (9.4 Tesla, temporal resolution = 38 milliseconds) from female rats three anesthesia conditions. Power at frequencies extending up to 0.3 Hz is detected consistently rat brains modulated by level. Principal component analysis reveals a repertoire modes, which transient oscillations organize fixed phase relationships distinct cortical subcortical structures. Oscillatory modes found vary between conditions, resonating faster under medetomidine sedation reducing both number, frequency, duration addition isoflurane. Peaking power within clear anatomical boundaries, these oscillatory point an emergent systemic property. This work provides additional insight into origin organizing principles underpinning spontaneous long-range connectivity.

Язык: Английский

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Functional brain networks reflect spatial and temporal autocorrelation

Nature Neuroscience, Год журнала: 2023, Номер 26(5), С. 867 - 878

Опубликована: Апрель 24, 2023

Язык: Английский

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Multimodal measures of spontaneous brain activity reveal both common and divergent patterns of cortical functional organization

Nature Communications, Год журнала: 2024, Номер 15(1)

Опубликована: Янв. 3, 2024

Abstract Large-scale functional networks have been characterized in both rodent and human brains, typically by analyzing fMRI-BOLD signals. However, the relationship between underlying neural activity is complex incompletely understood, which poses challenges to interpreting network organization obtained using this technique. Additionally, most work has assumed a disjoint (i.e., brain regions belong one only network). Here, we employ wide-field Ca 2+ imaging simultaneously with mice expressing GCaMP6f excitatory neurons. We determine cortical discovered each modality mixed-membership algorithm test hypothesis that exhibit overlapping organization. find there considerable overlap (both modalities) addition Our results show multiple BOLD are detected via signals, determined low-frequency signals modestly more similar networks. In addition, principal gradient of connectivity nearly identical for Despite similarities, important differences also across modalities, such as measures strength diversity. conclusion, uncovers mouse reflects several, but not all, properties observed

Язык: Английский

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Distinct neurochemical influences on fMRI response polarity in the striatum

Nature Communications, Год журнала: 2024, Номер 15(1)

Опубликована: Март 1, 2024

Abstract The striatum, known as the input nucleus of basal ganglia, is extensively studied for its diverse behavioral roles. However, relationship between neuronal and vascular activity, vital interpreting functional magnetic resonance imaging (fMRI) signals, has not received comprehensive examination within striatum. Here, we demonstrate that optogenetic stimulation dorsal striatal neurons or their afferents from various cortical subcortical regions induces negative fMRI responses in rats, manifesting vasoconstriction. These occur even with heightened confirmed by electrophysiology fiber-photometry. In parallel, midbrain dopaminergic neuron modulation, coupled electrochemical measurements, establishes a link vasodilation dopamine release. Intriguingly, vivo intra-striatal pharmacological manipulations during highlight critical role opioidergic signaling generating This observation substantiated detecting vasoconstriction brain slices after synthetic opioid application. humans, aimed at increasing activity likewise elicit responses. Our results emphasize necessity considering vasoactive neurotransmission alongside when signal.

Язык: Английский

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What have we really learned from functional connectivity in clinical populations?

NeuroImage, Год журнала: 2021, Номер 242, С. 118466 - 118466

Опубликована: Авг. 10, 2021

Functional connectivity (FC), or the statistical interdependence of blood-oxygen dependent level (BOLD) signals between brain regions using fMRI, has emerged as a widely used tool for probing functional abnormalities in clinical populations due to promise approach across conceptual, technical, and practical levels. With an already vast steadily accumulating neuroimaging literature on neurodevelopmental, psychiatric, neurological diseases disorders which FC is primary measure, we aim here provide high-level synthesis major concepts that have arisen from findings manner cuts different conditions sheds light overarching principles. We highlight allowed us discover ubiquity intrinsic networks virtually all brains clarify typical patterns neurodevelopment over lifespan. This understanding maturation with age provided important benchmarks against evaluate divergent early life degeneration late life. turn led insight many are associated complex, distributed, network-level changes brain, opposed solely focal abnormalities. further emphasize role studies played supporting dimensional studying transdiagnostic symptoms enhancing multimodal characterization prediction trajectory symptom progression conditions. unprecedented opportunity offered by probe where function could not be easily studied otherwise, such consciousness. Lastly, suggest high priority areas future research acknowledge critical barriers use methods, particularly those related artifact removal, data denoising feasibility contexts.

Язык: Английский

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Neurovascular coupling and bilateral connectivity during NREM and REM sleep

eLife, Год журнала: 2020, Номер 9

Опубликована: Окт. 29, 2020

To understand how arousal state impacts cerebral hemodynamics and neurovascular coupling, we monitored neural activity, behavior, hemodynamic signals in un-anesthetized, head-fixed mice. Mice frequently fell asleep during imaging, these sleep events were interspersed with periods of wake. During both NREM REM sleep, mice showed large increases blood volume ([HbT]) arteriole diameter relative to the awake state, two five times larger than those evoked by sensory stimulation. NREM, amplitude bilateral low-frequency oscillations [HbT] increased markedly, coherency between activity was higher resting states. Bilateral correlations highest lowest state. Hemodynamic cortex are strongly modulated changes substantially sensory-evoked responses.

Язык: Английский

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nNOS-expressing interneurons control basal and behaviorally evoked arterial dilation in somatosensory cortex of mice

eLife, Год журнала: 2020, Номер 9

Опубликована: Окт. 5, 2020

Cortical neural activity is coupled to local arterial diameter and blood flow. However, which neurons control the dynamics of cerebral arteries not well understood. We dissected cellular mechanisms controlling basal evoked dilation in cortical awake, head-fixed mice. Locomotion drove robust dilation, increases gamma band power field potential (LFP), calcium signals pyramidal neuronal nitric oxide synthase (nNOS)-expressing neurons. Chemogenetic or pharmocological modulation overall up down caused corresponding decreases diameter. Modulation neuron alone had little effect on despite pronounced changes LFP. nNOS-expressing without population activity.

Язык: Английский

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