Neocortical Layer 1: An Elegant Solution to Top-Down and Bottom-Up Integration

Annual Review of Neuroscience, Journal Year: 2021, Volume and Issue: 44(1), P. 221 - 252

Published: March 17, 2021

Many of our daily activities, such as riding a bike to work or reading book in noisy cafe, and highly skilled professional playing tennis match violin concerto, depend upon the ability brain quickly make moment-to-moment adjustments behavior response results actions. Particularly, they neocortex integrate information provided by sensory organs (bottom-up information) with internally generated signals expectations attentional (top-down information). This integration occurs pyramidal cells (PCs) their long apical dendrite, which branches extensively into dendritic tuft layer 1 (L1). The outermost neocortex, L1 is conserved across cortical areas species. Importantly, predominant input for top-down information, relayed rich, dense mesh long-range projections that provide PCs. Here, we discuss recent progress understanding composition review evidence processing contributes functions perception, cross-modal integration, controlling states consciousness, attention, learning.

Language: Английский

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Glutamate indicators with improved activation kinetics and localization for imaging synaptic transmission

Nature Methods, Journal Year: 2023, Volume and Issue: 20(6), P. 925 - 934

Published: May 4, 2023

Abstract The fluorescent glutamate indicator iGluSnFR enables imaging of neurotransmission with genetic and molecular specificity. However, existing variants exhibit low in vivo signal-to-noise ratios, saturating activation kinetics exclusion from postsynaptic densities. Using a multiassay screen bacteria, soluble protein cultured neurons, we generated improved ratios kinetics. We developed surface display constructs that improve iGluSnFR’s nanoscopic localization to postsynapses. resulting iGluSnFR3 exhibits rapid nonsaturating reports synaptic release decreased saturation increased specificity versus extrasynaptic signals neurons. Simultaneous electrophysiology at individual boutons mouse visual cortex showed transients report single action potentials high In vibrissal sensory layer 4, used characterize distinct patterns touch-evoked feedforward input thalamocortical both recurrent onto L4 cortical neuron dendritic spines.

Language: Английский

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Two-photon calcium imaging of neuronal activity

Nature Reviews Methods Primers, Journal Year: 2022, Volume and Issue: 2(1)

Published: Sept. 1, 2022

Language: Английский

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Learning binds new inputs into functional synaptic clusters via spinogenesis

Nature Neuroscience, Journal Year: 2022, Volume and Issue: 25(6), P. 726 - 737

Published: June 1, 2022

Language: Английский

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Cortico-cortical feedback engages active dendrites in visual cortex

Nature, Journal Year: 2023, Volume and Issue: 617(7962), P. 769 - 776

Published: May 3, 2023

Abstract Sensory processing in the neocortex requires both feedforward and feedback information flow between cortical areas 1 . In processing, higher-level representations provide contextual to lower levels, facilitate perceptual functions such as contour integration figure–ground segmentation 2,3 However, we have limited understanding of circuit cellular mechanisms that mediate influence. Here use long-range all-optical connectivity mapping mice show influence from lateromedial higher visual area (LM) primary cortex (V1) is spatially organized. When source target represent same space, relatively suppressive. By contrast, when offset facilitating. Two-photon calcium imaging data this facilitating nonlinearly integrated apical tuft dendrites V1 pyramidal neurons: retinotopically (surround) stimuli drive local dendritic signals indicative regenerative events, two-photon optogenetic activation LM neurons projecting identified feedback-recipient spines can similar branch-specific signals. Our results how neocortical nonlinear together form a substrate support predictive cooperative interactions.

Language: Английский

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A neurophysiological basis for aperiodic EEG and the background spectral trend

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: Feb. 19, 2024

Abstract Electroencephalograms (EEGs) display a mixture of rhythmic and broadband fluctuations, the latter manifesting as an apparent 1/f spectral trend. While network oscillations are known to generate EEG, neural basis EEG remains unexplained. Here, we use biophysical modelling show that aperiodic activity can detectable scalp potentials shape features, but these signals do not significantly perturb brain rhythm quantification. Further model analysis demonstrated profoundly corrupted by shifts in synapse properties. To examine this scenario, recorded EEGs human subjects being administered propofol, general anesthetic GABA receptor agonist. Drug administration caused changes quantitatively matched propofol’s effects on receptors. We used our correct for confounding changes, which revealed delta power, uniquely, increased within seconds individuals losing consciousness. Altogether, work details how shaped neurophysiological factors other than rhythms elucidates undermine traditional interpretation.

Language: Английский

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Multiphoton fluorescence microscopy for in vivo imaging

Cell, Journal Year: 2024, Volume and Issue: 187(17), P. 4458 - 4487

Published: Aug. 1, 2024

Language: Английский

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Interpreting in vivo calcium signals from neuronal cell bodies, axons, and dendrites: a review

Neurophotonics, Journal Year: 2019, Volume and Issue: 7(01), P. 1 - 1

Published: July 30, 2019

Calcium imaging is emerging as a popular technique in neuroscience. A major reason that intracellular calcium transients are reflections of electrical events neurons. For example, influx the soma and axonal boutons accompanies spiking activity, whereas elevations dendrites dendritic spines associated with synaptic inputs local regenerative events. However, have complex spatiotemporal dynamics, since most optical methods visualize only one somatic, axonal, compartments, straightforward inference underlying event typically challenging. We highlight experiments directly calibrated in vivo signals recorded using fluorescent indicators against electrophysiological address commonly asked questions such as: Can be used to characterize neurons high firing rates? signal report decrease activity? What evidence subcellular compartments correspond distinct presynaptic postsynaptic events? By reviewing empirical limitations, we suggest that, despite some caveats, versatile method variety neuronal vivo.

Language: Английский

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Cortical response selectivity derives from strength in numbers of synapses

Nature, Journal Year: 2020, Volume and Issue: 590(7844), P. 111 - 114

Published: Dec. 16, 2020

Language: Английский

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A Dendrite-Focused Framework for Understanding the Actions of Ketamine and Psychedelics

Trends in Neurosciences, Journal Year: 2020, Volume and Issue: 44(4), P. 260 - 275

Published: Dec. 21, 2020

Language: Английский

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