keyword
MENU ▼
Read by QxMD icon Read
search

Feedforward Inhibition

keyword
https://www.readbyqxmd.com/read/28625487/distinct-feedforward-and-feedback-effects-of-microstimulation-in-visual-cortex-reveal-neural-mechanisms-of-texture-segregation
#1
P Christiaan Klink, Bruno Dagnino, Marie-Alice Gariel-Mathis, Pieter R Roelfsema
The visual cortex is hierarchically organized, with low-level areas coding for simple features and higher areas for complex ones. Feedforward and feedback connections propagate information between areas in opposite directions, but their functional roles are only partially understood. We used electrical microstimulation to perturb the propagation of neuronal activity between areas V1 and V4 in monkeys performing a texture-segregation task. In both areas, microstimulation locally caused a brief phase of excitation, followed by inhibition...
June 9, 2017: Neuron
https://www.readbyqxmd.com/read/28617659/inhibitory-interneurons-in-the-retina-types-circuitry-and-function
#2
Jeffrey S Diamond
Visual signals in the vertebrate retina are shaped by feedback and feedforward inhibition in two synaptic layers. In one, horizontal cells establish fundamental center-surround receptive-field properties via morphologically and physiologically complex synapses with photoreceptors and bipolar cells. In the other, a panoply of amacrine cells imbue ganglion cell responses with spatiotemporally complex information about the visual world. Here, I review current ideas about horizontal cell signaling, considering the evidence for and against the leading, competing theories...
June 15, 2017: Annual Review of Vision Science
https://www.readbyqxmd.com/read/28599115/recurrent-information-optimization-with-local-metaplastic-synaptic-dynamics
#3
Sensen Liu, ShiNung Ching
We consider the problem of optimizing information-theoretic quantities in recurrent networks via synaptic learning. In contrast to feedforward networks, the recurrence presents a key challenge insofar as an optimal learning rule must aggregate the joint distribution of the whole network. This challenge, in particular, makes a local policy (i.e., one that depends on only pairwise interactions) difficult. Here, we report a local metaplastic learning rule that performs approximate optimization by estimating whole-network statistics through the use of several slow, nested dynamical variables...
June 9, 2017: Neural Computation
https://www.readbyqxmd.com/read/28598717/inhibitory-plasticity-balance-control-and-codependence
#4
Guillaume Hennequin, Everton J Agnes, Tim P Vogels
Inhibitory neurons, although relatively few in number, exert powerful control over brain circuits. They stabilize network activity in the face of strong feedback excitation and actively engage in computations. Recent studies reveal the importance of a precise balance of excitation and inhibition in neural circuits, which often requires exquisite fine-tuning of inhibitory connections. Wereview inhibitory synaptic plasticity and its roles in shaping both feedforward and feedback control. We discuss the necessity of complex, codependent plasticity mechanisms to build nontrivial, functioning networks, and we end by summarizing experimental evidence of such interactions...
June 9, 2017: Annual Review of Neuroscience
https://www.readbyqxmd.com/read/28591219/mechanisms-underlying-a-thalamocortical-transformation-during-active-tactile-sensation
#5
Diego Adrian Gutnisky, Jianing Yu, Samuel Andrew Hires, Minh-Son To, Michael Bale, Karel Svoboda, David Golomb
During active somatosensation, neural signals expected from movement of the sensors are suppressed in the cortex, whereas information related to touch is enhanced. This tactile suppression underlies low-noise encoding of relevant tactile features and the brain's ability to make fine tactile discriminations. Layer (L) 4 excitatory neurons in the barrel cortex, the major target of the somatosensory thalamus (VPM), respond to touch, but have low spike rates and low sensitivity to the movement of whiskers. Most neurons in VPM respond to touch and also show an increase in spike rate with whisker movement...
June 7, 2017: PLoS Computational Biology
https://www.readbyqxmd.com/read/28498919/chemicogenetic-restoration-of-the-prefrontal-cortex-to-amygdala-pathway-ameliorates-stress-induced-deficits
#6
Jing Wei, Ping Zhong, Luye Qin, Tao Tan, Zhen Yan
Corticosteroid stress hormones exert a profound impact on cognitive and emotional processes. Understanding the neuronal circuits that are altered by chronic stress is important for counteracting the detrimental effects of stress in a brain region- and cell type-specific manner. Using the chemogenetic tool, Designer Receptors Exclusively Activated by Designer Drugs (DREADDs), which enables the remote, noninvasive and long-lasting modulation of cellular activity and signal transduction in discrete neuronal populations in vivo, we sought to identify the specific pathways that play an essential role in stress responses...
May 11, 2017: Cerebral Cortex
https://www.readbyqxmd.com/read/28472661/chronic-loss-of-ca2-transmission-leads-to-hippocampal-hyperexcitability
#7
Roman Boehringer, Denis Polygalov, Arthur J Y Huang, Steven J Middleton, Vincent Robert, Marie E Wintzer, Rebecca A Piskorowski, Vivien Chevaleyre, Thomas J McHugh
Hippocampal CA2 pyramidal cells project into both the neighboring CA1 and CA3 subfields, leaving them well positioned to influence network physiology and information processing for memory and space. While recent work has suggested unique roles for CA2, including encoding position during immobility and generating ripple oscillations, an interventional examination of the integrative functions of these connections has yet to be reported. Here we demonstrate that CA2 recruits feedforward inhibition in CA3 and that chronic genetically engineered shutdown of CA2-pyramidal-cell synaptic transmission consequently results in increased excitability of the recurrent CA3 network...
May 3, 2017: Neuron
https://www.readbyqxmd.com/read/28471714/circuits-and-mechanisms-for-surround-modulation-in-visual-cortex
#8
Alessandra Angelucci, Maryam Bijanzadeh, Lauri Nurminen, Frederick Federer, Sam Merlin, Paul C Bressloff
Surround modulation (SM) is a fundamental property of sensory neurons in many species and sensory modalities. SM is the ability of stimuli in the surround of a neuron's receptive field (RF) to modulate (typically suppress) the neuron's response to stimuli simultaneously presented inside the RF, a property thought to underlie optimal coding of sensory information and important perceptual functions. Understanding the circuit and mechanisms for SM can reveal fundamental principles of computations in sensory cortices, from mouse to human...
May 3, 2017: Annual Review of Neuroscience
https://www.readbyqxmd.com/read/28461661/measuring-feedforward-inhibition-and-its-impact-on-local-circuit-function
#9
Court Hull
This protocol describes a series of approaches to measure feedforward inhibition in acute brain slices from the cerebellar cortex. Using whole-cell voltage and current clamp recordings from Purkinje cells in conjunction with electrical stimulation of the parallel fibers, these methods demonstrate how to measure the relationship between excitation and inhibition in a feedforward circuit. This protocol also describes how to measure the impact of feedforward inhibition on Purkinje cell excitability, with an emphasis on spike timing...
May 1, 2017: Cold Spring Harbor Protocols
https://www.readbyqxmd.com/read/28438969/intracellular-in-vivo-dynamics-of-thalamocortical-synapses-in-visual-cortex
#10
Madineh Sedigh-Sarvestani, Leif Vigeland, Ivan Fernandez-Lamo, M Morgan Taylor, Larry A Palmer, Diego Contreras
Seminal studies of the thalamocortical circuit in the visual system of the cat have been central to our understanding of sensory encoding. However, thalamocortical synaptic properties remain poorly understood. We used paired recordings, in the lateral geniculate nucleus (LGN) and primary visual cortex (V1), to provide the first in vivo characterization of sensory-driven thalamocortical potentials in V1. The amplitudes of EPSPs we characterized were smaller than those previously reported in vitro Consistent with prior findings, connected LGN-V1 pairs were only found when their receptive fields (RFs) overlapped, and the probability of connection increased steeply with degree of RF overlap and response similarity...
May 24, 2017: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
https://www.readbyqxmd.com/read/28432122/dual-regulation-of-stat1-and-stat3-by-the-tumor-suppressor-protein-pml-contributes-to-interferon-%C3%AE-mediated-inhibition-of-angiogenesis
#11
Kuo-Sheng Hsu, Xuan Zhao, Xiwen Cheng, Dongyin Guan, Ganapati H Mahabeleshwar, Yu Liu, Ernest Borden, Mukesh K Jain, Hung-Ying Kao
IFNs are effective in inhibiting angiogenesis in preclinical models and in treating several angioproliferative disorders. However, the detailed mechanisms of IFNα-mediated anti-angiogenesis are not completely understood. Stat1/2/3 and PML are IFNα downstream effectors and are pivotal regulators of angiogenesis. Here, we investigated PML's role in the regulation of Stat1/2/3 activity. In Pml knock-out (KO) mice, ablation of Pml largely reduces IFNα angiostatic ability in Matrigel plug assays. This suggested an essential role for PML in IFNα's anti-angiogenic function...
June 16, 2017: Journal of Biological Chemistry
https://www.readbyqxmd.com/read/28374012/activation-of-ras-erk-signaling-and-gsk-3-by-amyloid-precursor-protein-and-amyloid-beta-facilitates-neurodegeneration-in-alzheimer-s-disease
#12
Lisa Kirouac, Alexander J Rajic, David H Cribbs, Jaya Padmanabhan
It is widely accepted that amyloid β (Aβ) generated from amyloid precursor protein (APP) oligomerizes and fibrillizes to form neuritic plaques in Alzheimer's disease (AD), yet little is known about the contribution of APP to intracellular signaling events preceding AD pathogenesis. The data presented here demonstrate that APP expression and neuronal exposure to oligomeric Aβ42 enhance Ras/ERK signaling cascade and glycogen synthase kinase 3 (GSK-3) activation. We find that RNA interference (RNAi)-directed knockdown of APP in B103 rat neuroblastoma cells expressing APP inhibits Ras-ERK signaling and GSK-3 activation, indicating that APP acts upstream of these signal transduction events...
March 2017: ENeuro
https://www.readbyqxmd.com/read/28334225/pom-thalamocortical-input-drives-layer-specific-microcircuits-in-somatosensory-cortex
#13
Nicholas J Audette, Joanna Urban-Ciecko, Megumi Matsushita, Alison L Barth
Higher-order thalamic nuclei, such as the posterior medial nucleus (POm) in the somatosensory system or the pulvinar in the visual system, densely innervate the cortex and can influence perception and plasticity. To systematically evaluate how higher-order thalamic nuclei can drive cortical circuits, we investigated cell-type selective responses to POm stimulation in mouse primary somatosensory (barrel) cortex, using genetically targeted whole-cell recordings in acute brain slices. We find that ChR2-evoked thalamic input selectively targets specific cell types in the neocortex, revealing layer-specific modules for the summation and processing of POm input...
March 10, 2017: Cerebral Cortex
https://www.readbyqxmd.com/read/28329692/organization-of-functional-long-range-circuits-controlling-the-activity-of-serotonergic-neurons-in-the-dorsal-raphe-nucleus
#14
Li Zhou, Ming-Zhe Liu, Qing Li, Juan Deng, Di Mu, Yan-Gang Sun
Serotonergic neurons play key roles in various biological processes. However, circuit mechanisms underlying tight control of serotonergic neurons remain largely unknown. Here, we systematically investigated the organization of long-range synaptic inputs to serotonergic neurons and GABAergic neurons in the dorsal raphe nucleus (DRN) of mice with a combination of viral tracing, slice electrophysiological, and optogenetic techniques. We found that DRN serotonergic neurons and GABAergic neurons receive largely comparable synaptic inputs from six major upstream brain areas...
March 21, 2017: Cell Reports
https://www.readbyqxmd.com/read/28283576/glucocorticoid-and-cytokine-crosstalk-feedback-feedforward-and-co-regulatory-interactions-determine-repression-or-resistance
#15
REVIEW
Robert Newton, Suharsh Shah, Mohammed O Altonsy, Antony N Gerber
Inflammatory signals induce feedback and feedforward systems that provide temporal control. Although glucocorticoids can repress inflammatory gene expression, glucocorticoid receptor recruitment increases expression of negative feedback and feedforward regulators, including the phosphatase, DUSP1, the ubiquitin-modifying enzyme, TNFAIP3, or the mRNA-destabilizing protein, ZFP36. Moreover, glucocorticoid receptor cooperativity with factors, including nuclear factor-κB (NF-κB), may enhance regulator expression to promote repression...
April 28, 2017: Journal of Biological Chemistry
https://www.readbyqxmd.com/read/28273455/a-bach2-cebp-gene-regulatory-network-for-the-commitment-of-multipotent-hematopoietic-progenitors
#16
Ari Itoh-Nakadai, Mitsuyo Matsumoto, Hiroki Kato, Junichi Sasaki, Yukihiro Uehara, Yuki Sato, Risa Ebina-Shibuya, Mizuho Morooka, Ryo Funayama, Keiko Nakayama, Kyoko Ochiai, Akihiko Muto, Kazuhiko Igarashi
Hematopoietic stem cell and multipotent progenitor (MPP) commitment can be tuned in response to an infection so that their differentiation is biased toward myeloid cells. Here, we find that Bach2, which inhibits myeloid differentiation in common lymphoid progenitors, represses a cohort of myeloid genes and activates those linked to lymphoid function. Bach2 repressed both Cebpb and its target Csf1r, encoding C/EBPβ and macrophage colony-stimulating factor receptor (M-CSFr), respectively, whereas C/EBPβ repressed Bach2 and activated Csf1r...
March 7, 2017: Cell Reports
https://www.readbyqxmd.com/read/28238186/effects-of-hallucinogens-on-neuronal-activity
#17
L Lladó-Pelfort, P Celada, M S Riga, E Troyano-Rodríguez, N Santana, F Artigas
Hallucinogens evoke sensory, perceptual, affective, and cognitive effects that may be useful to understand the neurobiological basis of mood and psychotic disorders. The present chapter reviews preclinical research carried out in recent years in order to better understand the action of psychotomimetic agents such as the noncompetitive NMDA receptor (NMDA-R) antagonists and serotonergic hallucinogens. Our studies have focused on the mechanisms through which these agents alter cortical activity. Noncompetitive NMDA-R antagonists, such as phencyclidine (PCP) and MK-801 (dizocilpine), as well as the serotonergic hallucinogens DOI and 5-MeO-DMT, produce similar effects on cellular and population activity in prefrontal cortex (PFC); these effects include alterations of pyramidal neuron discharge (with an overall increase in firing), as well as a marked attenuation of the low frequency oscillations (0...
February 26, 2017: Current Topics in Behavioral Neurosciences
https://www.readbyqxmd.com/read/28218241/massively-augmented-hippocampal-dentate-granule-cell-activation-accompanies-epilepsy-development
#18
Christopher G Dengler, Cuiyong Yue, Hajime Takano, Douglas A Coulter
In a mouse model of temporal lobe epilepsy, multicellular calcium imaging revealed that disease emergence was accompanied by massive amplification in the normally sparse, afferent stimulation-induced activation of hippocampal dentate granule cells. Patch recordings demonstrated reductions in local inhibitory function within the dentate gyrus at time points where sparse activation was compromised. Mimicking changes in inhibitory synaptic function and transmembrane chloride regulation was sufficient to elicit the dentate gyrus circuit collapse evident during epilepsy development...
February 20, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28203201/modulation-of-synaptic-plasticity-in-the-cortex-needs-to-understand-all-the-players
#19
REVIEW
Claire N J Meunier, Pascal Chameau, Philippe M Fossier
The prefrontal cortex (PFC) is involved in cognitive tasks such as working memory, decision making, risk assessment and regulation of attention. These functions performed by the PFC are supposed to rely on rhythmic electrical activity generated by neuronal network oscillations determined by a precise balance between excitation and inhibition balance (E/I balance) resulting from the coordinated activities of recurrent excitation and feedback and feedforward inhibition. Functional alterations in PFC functions have been associated with cognitive deficits in several pathologies such as major depression, anxiety and schizophrenia...
2017: Frontiers in Synaptic Neuroscience
https://www.readbyqxmd.com/read/28195311/reduced-local-input-to-fast-spiking-interneurons-in-the-somatosensory-cortex-in-the-gabaa-%C3%AE-2-r43q-mouse-model-of-absence-epilepsy
#20
Stephen P Currie, Liliana L Luz, Sam A Booker, David J A Wyllie, Peter C Kind, Michael I Daw
OBJECTIVE: Absence seizures in childhood absence epilepsy are initiated in the thalamocortical (TC) system. We investigated if these seizures result from altered development of the TC system before the appearance of seizures in mice containing a point mutation in γ-aminobutyric acid A (GABAA ) receptor γ2 subunits linked to childhood absence epilepsy (R43Q). Findings from conditional mutant mice indicate that expression of normal γ2 subunits during preseizure ages protect from later seizures...
April 2017: Epilepsia
keyword
keyword
96761
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"