Membrane potential correlates of network decorrelation and improved SNR by cholinergic activation in the somatosensory cortex

Mapping Intimacies ◽

10.1101/240853 ◽

2017 ◽

Author(s):

Inbal Meir ◽

Yonatan Katz ◽

Ilan Lampl

Keyword(s):

Membrane Potential ◽

Differential Effect ◽

Barrel Cortex ◽

Signal To Noise Ratio ◽

Nucleus Basalis ◽

Sensory Response ◽

Layer 4 ◽

Underlying Mechanisms ◽

Sensory Evoked ◽

Cholinergic Activation

AbstractThe nucleus basalis (NB) projects cholinergic axons to the cortex where they play a major role in arousal, attention and learning. Cholinergic inputs shift cortical dynamics from synchronous to asynchronous and improves the signal to noise ratio (SNR) of sensory response. Yet, the underlying mechanisms of these changes remain unclear. Using simultaneous extracellular and whole cell patch recordings in layer 4 barrel cortex we show that activation of the cholinergic system has a differential effect on ongoing and sensory evoked activities. Cholinergic activation eliminated the large and correlated spontaneous synaptic fluctuations in membrane potential while sparing the synaptic response to whisker stimulation. This differential effect of cholinergic activation provides a unified explanation for the increased SNR of sensory response and for the reduction in both trial to trial variability and noise correlations as well as explaining the shift into desynchronized cortical state which are the hallmarks of arousal and attention.

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Local and thalamic origins of ongoing and sensory evoked cortical correlations

10.1101/058727 ◽

2016 ◽

Cited By ~ 1

Author(s):

Katayun Cohen-Kashi Malina ◽

Boaz Mohar ◽

Akiva N. Rappaport ◽

Miao Liu

Keyword(s):

Barrel Cortex ◽

Field Potential ◽

Sensory Response ◽

Cortical Cells ◽

Synaptic Inputs ◽

Correlated Activity ◽

Layer 4 ◽

Lower Variability ◽

Intact Cortex ◽

Sensory Evoked

Thalamic inputs of layer 4 (L4) cells in sensory cortices are outnumbered by local connections. Thus, it was suggested that robust sensory response in L4 emerges due to synchronized thalamic activity. In order to investigate the role of both inputs in generation of cortical synchronization, we isolated the thalamic excitatory inputs of cortical cells by optogenetically silencing cortical firing. In anesthetized mice, we measured the correlation between isolated thalamic synaptic inputs of simultaneously patched nearby L4 cells of the barrel cortex. In contrast to correlated activity of excitatory synaptic inputs in the intact cortex, isolated thalamic inputs exhibit lower variability and asynchronous spontaneous and sensory evoked inputs. These results were further supported in awake mice when we recorded the excitatory inputs of individual cortical cells simultaneously with the local field potential (LFP) in a nearby site. Our results therefore indicate that cortical synchronization emerges by intracortical coupling.

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Analysis of LFP Phase Predicts Sensory Response of Barrel Cortex

Journal of Neurophysiology ◽

10.1152/jn.01288.2005 ◽

2006 ◽

Vol 96 (3) ◽

pp. 1658-1663 ◽

Cited By ~ 28

Author(s):

R. Haslinger ◽

I. Ulbert ◽

C. I. Moore ◽

E. N. Brown ◽

A. Devor

Keyword(s):

Barrel Cortex ◽

Temporal Dynamics ◽

Field Potential ◽

Electrode Array ◽

Sensory Response ◽

Strong Function ◽

Large Populations ◽

Up And Down States ◽

Sensory Evoked ◽

Local Field Potential Lfp

Several previous studies have shown the existence of Up and Down states and have linked their magnitude (e.g., depolarization level) to the size of sensory-evoked responses. Here, we studied how the temporal dynamics of such states influence the sensory-evoked response to vibrissa deflection. Under α-chloralose anesthesia, barrel cortex exhibits strong quasi-periodic ∼1-Hz local field potential (LFP) oscillations generated by the synchronized fluctuation of large populations of neurons between depolarized (Up) and hyperpolarized (Down) states. Using a linear depth electrode array, we recorded the LFP and multiunit activity (MUA) simultaneously across multiple layers of the barrel column and used the LFP to approximate the subthreshold Up–Down fluctuations. Our central finding is that the MUA response is a strong function of the LFP oscillation’s phase. When only ongoing LFP magnitude was considered, the response was largest in the Down state, in agreement with previous studies. However, consideration of the LFP phase revealed that the MUA response varied smoothly as a function of LFP phase in a manner that was not monotonically dependent on LFP magnitude. The LFP phase is therefore a better predictor of the MUA response than the LFP magnitude is. Our results suggest that, in the presence of ongoing oscillations, there can be a continuum of response properties and that each phase may, at times, need to be considered a distinct cortical state.

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Modulation of Sensory Response at Different Time Lags after Locus Coeruleus Micro-stimulation

10.1101/2020.07.09.188615 ◽

2020 ◽

Author(s):

Zeinab Fazlali ◽

Yadollah Ranjbar-Slamloo ◽

Ehsan Arabzadeh

Keyword(s):

Locus Coeruleus ◽

Sensory Input ◽

Barrel Cortex ◽

Temporal Integration ◽

Time Lag ◽

Evoked Response ◽

Sensory Response ◽

Time Lags ◽

Biphasic Effect ◽

Sensory Evoked

AbstractLocus Coeruleus (LC) noradrenergic system has widespread projections throughout the brain and affects sensory processing in various modalities. Inhibition of both spontaneous and sensory-evoked cortical activity is well-documented in early experiments by either LC electrical micro-stimulation or local application of norepinephrine (NE). However, the temporal profile of LC modulation of sensory response is not well-established. Here, we recorded neuronal activity from the rat barrel cortex under urethane anesthesia and coupled LC micro-stimulation with brief mechanical deflection of whiskers at 10 different time lags (50-500 ms). LC micro-stimulation exhibited a biphasic effect on BC spontaneous activity: a period of suppression (∼100 ms) followed by a period of excitation (∼200 ms). This profile was highly consistent across BC units: 82% of BC units showed early suppression and 91% of BC units showed late excitation. We observed a similar effect on the sensory-evoked response: at 50-ms lag, the evoked response (1-75 ms after deflection onset) decreased in 77% of units and at 150-ms lag, the early evoked response was facilitated in 85% of units. At 150 to 350-ms time lags, LC micro-stimulation caused a combined facilitation followed by suppression on the evoked response. For lags of 400-ms and higher, the effect was pure facilitation. Additionally, response latency was significantly decreased at 250 ms time lag. In summary, we found that LC modulation affects the cortical processing of sensory inputs in a complex manner which critically depends on the time lag between LC activation and sensory input. These results have clear implications for temporal integration of sensory input and its noradrenergic modulation in a behavioral setting.

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Contribution of interneuron subtype-specific GABAergic signalling to emergent sensory processing in somatosensory whisker barrel cortex in mouse

10.1101/2021.02.18.431791 ◽

2021 ◽

Author(s):

Liad J. Baruchin ◽

Michael M. Kohl ◽

Simon J.B Butt

Keyword(s):

Sensory Processing ◽

Barrel Cortex ◽

Sensory Information ◽

Gaba Release ◽

Gabaergic Interneuron ◽

Dependent Manner ◽

Sensory Adaptation ◽

Layer 4 ◽

Evoked Activity ◽

Sensory Evoked

AbstractMammalian neocortex is important for conscious processing of sensory information. Fundamental to this function is balanced glutamatergic and GABAergic signalling. Yet little is known about how this interaction arises in the developing forebrain despite increasing insight into early GABAergic interneuron (IN) circuits. To further study this, we assessed the contribution of specific INs to the development of sensory processing in the mouse whisker barrel cortex. Specifically we explored the role of INs in speed coding and sensory adaptation. In wild-type animals, both speed processing and adaptation were present as early as the layer 4 critical period of plasticity, and showed refinement over the period leading to active whisking onset. We then conditionally silenced action-potential-dependent GABA release in either somatostatin (SST) or vasoactive intestinal peptide (VIP) INs. These genetic manipulations influenced both spontaneous and sensory-evoked activity in an age and layer-dependent manner. Silencing SST+ INs reduced early spontaneous activity and abolished facilitation in sensory adaptation observed in control pups. In contrast, VIP+ IN silencing had an effect towards the onset of active whisking. Silencing either IN subtype had no effect on speed coding. Our results reveal how these IN subtypes differentially contribute to early sensory processing over the first few postnatal weeks.

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Contribution of Interneuron Subtype-Specific GABAergic Signaling to Emergent Sensory Processing in Mouse Somatosensory Whisker Barrel Cortex

Cerebral Cortex ◽

10.1093/cercor/bhab363 ◽

2021 ◽

Author(s):

Liad J Baruchin ◽

Filippo Ghezzi ◽

Michael M Kohl ◽

Simon J B Butt

Keyword(s):

Sensory Processing ◽

Barrel Cortex ◽

Sensory Information ◽

Gaba Release ◽

Gabaergic Interneuron ◽

Dependent Manner ◽

Sensory Adaptation ◽

Genetic Manipulations ◽

Layer 4 ◽

Sensory Evoked

Abstract Mammalian neocortex is important for conscious processing of sensory information with balanced glutamatergic and GABAergic signaling fundamental to this function. Yet little is known about how this interaction arises despite increasing insight into early GABAergic interneuron (IN) circuits. To study this, we assessed the contribution of specific INs to the development of sensory processing in the mouse whisker barrel cortex, specifically the role of INs in early speed coding and sensory adaptation. In wild-type animals, both speed processing and adaptation were present as early as the layer 4 critical period of plasticity and showed refinement over the period leading to active whisking onset. To test the contribution of IN subtypes, we conditionally silenced action-potential-dependent GABA release in either somatostatin (SST) or vasoactive intestinal peptide (VIP) INs. These genetic manipulations influenced both spontaneous and sensory-evoked cortical activity in an age- and layer-dependent manner. Silencing SST + INs reduced early spontaneous activity and abolished facilitation in sensory adaptation observed in control pups. In contrast, VIP + IN silencing had an effect towards the onset of active whisking. Silencing either IN subtype had no effect on speed coding. Our results show that these IN subtypes contribute to early sensory processing over the first few postnatal weeks.

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Loss of Calretinin in L5a impairs the formation of the barrel cortex leading to abnormal whisker-mediated behaviors

Molecular Brain ◽

10.1186/s13041-021-00775-w ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Mingzhao Su ◽

Junhua Liu ◽

Baocong Yu ◽

Kaixing Zhou ◽

Congli Sun ◽

...

Keyword(s):

Information Integration ◽

Pyramidal Neurons ◽

Barrel Cortex ◽

Sensory Information ◽

Membrane Excitability ◽

Novelty Preference ◽

Layer 4 ◽

Dendritic Complexity ◽

Cortex System

AbstractThe rodent whisker-barrel cortex system has been established as an ideal model for studying sensory information integration. The barrel cortex consists of barrel and septa columns that receive information input from the lemniscal and paralemniscal pathways, respectively. Layer 5a is involved in both barrel and septa circuits and play a key role in information integration. However, the role of layer 5a in the development of the barrel cortex remains unclear. Previously, we found that calretinin is dynamically expressed in layer 5a. In this study, we analyzed calretinin KO mice and found that the dendritic complexity and length of layer 5a pyramidal neurons were significantly decreased after calretinin ablation. The membrane excitability and excitatory synaptic transmission of layer 5a neurons were increased. Consequently, the organization of the barrels was impaired. Moreover, layer 4 spiny stellate cells were not able to properly gather, leading to abnormal formation of barrel walls as the ratio of barrel/septum size obviously decreased. Calretinin KO mice exhibited deficits in exploratory and whisker-associated tactile behaviors as well as social novelty preference. Our study expands our knowledge of layer 5a pyramidal neurons in the formation of barrel walls and deepens the understanding of the development of the whisker-barrel cortex system.

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