The Experts below are selected from a list of 21384 Experts worldwide ranked by ideXlab platform
George V. Rebec - One of the best experts on this subject based on the ideXlab platform.
-
role of 5 ht2a and 5 ht2c b receptors in the acute effects of 3 4 methylenedioxymethamphetamine mdma on striatal Single Unit Activity and locomotion in freely moving rats
Psychopharmacology, 2005Co-Authors: Kevin T. Ball, George V. RebecAbstract:Rationale Like amphetamine, a locomotor-activating dose of 3,4-methylenedioxymethamphetamine (MDMA) predominantly excites striatal Single-Unit Activity in freely moving rats. Although both D1- and D2-like dopamine (DA) receptors play important roles in this effect, MDMA, unlike amphetamine, strongly increases both DA and serotonin (5-HT) transmission.
-
Role of 5-HT2A and 5-HT2C/B receptors in the acute effects of 3,4-methylenedioxymethamphetamine (MDMA) on striatal Single-Unit Activity and locomotion in freely moving rats.
Psychopharmacology, 2005Co-Authors: Kevin T. Ball, George V. RebecAbstract:Rationale Like amphetamine, a locomotor-activating dose of 3,4-methylenedioxymethamphetamine (MDMA) predominantly excites striatal Single-Unit Activity in freely moving rats. Although both D1- and D2-like dopamine (DA) receptors play important roles in this effect, MDMA, unlike amphetamine, strongly increases both DA and serotonin (5-HT) transmission.
-
Nucleus accumbens Single-Unit Activity in freely behaving male rats during approach to novel and non-novel estrus.
Neuroscience Letters, 2004Co-Authors: David A. Wood, Ann E.k. Kosobud, George V. RebecAbstract:To assess the role of nucleus accumbens (NAcc) during approach to novel sexually arousing stimuli, we evaluated NAcc Single-Unit Activity in male rats during the presentation of vaginal estrus extracted from novel and familiar female rats. After control stimulus presentations, animals were exposed to two estrous presentations from a female in the same or separate colony. A significantly larger proportion of Units increased firing rate in the novel (11/32; 34%) than the familiar condition (2/28; 7%) during approach to the first but not the second presentation. Response magnitudes to novel but not familiar estrus were also greater than those during control trials. Collectively, these results provide further evidence of a role for the NAcc in the processing of novel sexually arousing information.
-
Dissociation of core and shell Single-Unit Activity in the nucleus accumbens in free-choice novelty.
Behavioural Brain Research, 2003Co-Authors: David A. Wood, George V. RebecAbstract:Core and shell regions of the nucleus accumbens (NAcc) have been implicated in different aspects of goal-directed behavior. To assess these differences at the neuronal level, we evaluated core and shell Single-Unit Activity in eight rats during one-trial, free-choice entry into a novel compartment. Changes in firing rate during approach of (orientation toward) and entry into (nose cross) novelty were assessed relative to a pre-novelty baseline when the animals were behaviorally active. Increases and decreases in neuronal Activity were recorded in both regions during both phases of the novelty response. The regional distribution of these responses, however, was significantly different during the approach phase with roughly equal proportions of neuronal excitations (8/29) and inhibitions (6/29) in core but a shift away from excitation (2/40) toward inhibition (12/40) in shell. No regional differences emerged during subsequent approach of the familiar compartment from the novel chamber or during entry to either the novel or familiar compartment. Taken together, our results during approach to free-choice novelty indicate a regional dissociation in NAcc firing rate may play a role in appetitive behavior.
-
BMY‐14802, a sigma ligand and potential antipsychotic drug, reverses amphetamine‐induced changes in neostriatal Single‐Unit Activity in freely moving rats
Synapse, 1992Co-Authors: Zhongrui Wang, John L. Haracz, George V. RebecAbstract:The effects of BMY-14802 (5,10, or 20 mg/kg), a sigma-receptor ligand showing preclinical evidence of antipsychotic efficacy, were tested on Single-Unit Activity in the neostriatum of freely moving rats with or without pretreatment with 1.0 mg/kg D-amphetamine. Relative to resting baseline, amphetamine activated the large majority of neurons that changed firing rate in close temporal association with movement. All doses of BMY-14802 reversed this neuronal response, but the effect was most pronounced at 20 mg/kg. This dose, however, was equally likely to reverse or to induce a haloperidol-like potentiation of those neurons inhibited by amphetamine. In contrast, 10 mg/kg BMY-14802 consistently reversed amphetamine-induced neuronal inhibitions. All doses of BMY-14802 attenuated the locomotor effects of amphetamine, but only the higher doses also blocked other aspects of the amphetamine behavioral response. By itself, BMY-14802 dose dependently inhibited motor-related neurons, but elicited less behavioral activation than amphetamine. BMY-14802 (20 mg/kg) also induced hindlimb ataxia and occasional backwards locomotion. Haloperidol (1.0 mg/kg) reliably suppressed both behavior and neuronal Activity when injected 30 min after BMY-14802, whether or not amphetamine pretreatment was given. Thus, BMY-14802 shares with other neuroleptics the capacity to reverse amphetamine-induced excitations of neostriatal motor-related neurons, whereas other effects of BMY-14802 reveal some haloperidol-like actions at 20 mg/kg that do not occur at lower doses. © 1992 Wiley-Liss, Inc.
Kevin T. Ball - One of the best experts on this subject based on the ideXlab platform.
-
Role of 5-HT2A and 5-HT2C/B receptors in the acute effects of 3,4-methylenedioxymethamphetamine (MDMA) on striatal Single-Unit Activity and locomotion in freely moving rats.
Psychopharmacology, 2005Co-Authors: Kevin T. Ball, George V. RebecAbstract:Rationale Like amphetamine, a locomotor-activating dose of 3,4-methylenedioxymethamphetamine (MDMA) predominantly excites striatal Single-Unit Activity in freely moving rats. Although both D1- and D2-like dopamine (DA) receptors play important roles in this effect, MDMA, unlike amphetamine, strongly increases both DA and serotonin (5-HT) transmission.
-
role of 5 ht2a and 5 ht2c b receptors in the acute effects of 3 4 methylenedioxymethamphetamine mdma on striatal Single Unit Activity and locomotion in freely moving rats
Psychopharmacology, 2005Co-Authors: Kevin T. Ball, George V. RebecAbstract:Rationale Like amphetamine, a locomotor-activating dose of 3,4-methylenedioxymethamphetamine (MDMA) predominantly excites striatal Single-Unit Activity in freely moving rats. Although both D1- and D2-like dopamine (DA) receptors play important roles in this effect, MDMA, unlike amphetamine, strongly increases both DA and serotonin (5-HT) transmission.
Tony A Pham - One of the best experts on this subject based on the ideXlab platform.
-
monocular deprivation in adult mice alters visual acuity and Single Unit Activity
Learning & Memory, 2007Co-Authors: Quentin S Fischer, Aundrea Graves, Scott Evans, Marvin E Lickey, Tony A PhamAbstract:It has been discovered recently that monocular deprivation in young adult mice induces ocular dominance plasticity (ODP). This contradicts the traditional belief that ODP is restricted to a juvenile critical period. However, questions remain. ODP of young adults has been observed only using methods that are indirectly related to vision, and the plasticity of young adults appears diminished in comparison with juveniles. Therefore, we asked whether the newly discovered adult ODP broadly reflects plasticity of visual cortical function and whether it persists into full maturity. Single-Unit Activity is the standard physiological marker of visual cortical function. Using a more optimized protocol for recording Single-Units, we find evidence of adult ODP of Single-Units and show that it is most pronounced in deep cortical layers. Furthermore, using visual evoked potentials (VEP), we find that ODP is equally robust in young adults and mature adults and is observable after just one day of monocular deprivation. Finally, we find that monocular deprivation in adults changes spatial frequency thresholds of the VEP, decreasing the acuity of the deprived pathway and improving the acuity of the non-deprived pathway. Thus, in mice, the primary visual cortex is capable of remarkable adaptation throughout life.
Kazuo Okanoya - One of the best experts on this subject based on the ideXlab platform.
-
affective valence of neurons in the vicinity of the rat amygdala Single Unit Activity in response to a conditioned behavior and vocal sound playback
Behavioural Brain Research, 2017Co-Authors: Hiroko Kagawa, Yoshimasa Seki, Kazuo OkanoyaAbstract:Abstract We recorded Single Unit Activity within and around the rat amygdala while rats were engaged in an operant task (which included both reward and aversive trials) and during playback of ultrasonic vocalizations (USVs) to determine if there existed neurons which responded to two different types of either positive contexts (i.e., water reward and positively associated 50 kHz vocalizations) or negative contexts (i.e., white noise and negatively associated 22 kHz vocalizations). Ultimately, we wanted to determine if these two contexts (operant condition task and vocal sounds) could be represented as either positive or negative in a Single neuron. Neural Activity in 90% of cells was modulated in response to one or more of those events. A small number of those cells showed neural responses to both the aversive operant trials and 22 kHz USVs, but did not show responses to reward operant trials or 50 kHz USVs, suggesting the Activity of these neurons encodes for similar negative emotion in response to these two contexts. Some cells showed responses to either the reward trials or 50 kHz USVs, but no cells showed responses to both, suggesting that these cells do not show a common response to events associated with positive emotion. This might mean that 50 kHz vocal sounds and the operant rewards were segregated into two different categories within the neural representation at the level of the amygdala, even though it appeared that both events were associated with positive emotions in rats.
Gert Cauwenberghs - One of the best experts on this subject based on the ideXlab platform.
-
a computational framework for effective isolation of Single Unit Activity from in vivo electrophysiological recording
Biomedical Circuits and Systems Conference, 2017Co-Authors: Hristos S Courellis, Samuel U Nummela, Cory T Miller, Gert CauwenberghsAbstract:Modern spike sorting techniques are heavily reliant on unsupervised machine learning algorithms for isolation of Single-Unit Activity from noisy channel recordings. One of the most common methods, k-means clustering, is highly sensitive to the number of clusters selected (k) prior to analysis. A robust automated method for determining k is required, in particular for the large datasets currently being analyzed by the Neuroscience commUnity. Information criteria, often applied for this analysis, can yield over-fitted clustering recommendations and employ strong assumptions about cluster gaussianity which do not necessarily hold for real in-vivo neuro-electrophysiological recordings. An algorithmic approach to spike sorting is applied utilizing tandem multi-level wavelet decomposition and principal component analysis to construct a discriminant feature space. K-means clustering is applied to this feature space using a variety of distance metrics to determine which approach yields optimal cluster separation. Clustering outcomes are evaluated using the Entropic Product, an information entropy-based measure that makes no assumptions about the underlying distribution of spikes within a cluster. This measure is demonstrated to be more informative about clustering outcomes than other information criteria when sorting spike data collected using bundled microwire arrays implanted in the Primary Visual Cortex of marmosets conducting a visual-stimulation task.
-
BioCAS - A computational framework for effective isolation of Single-Unit Activity from in-vivo electrophysiological recording
2017 IEEE Biomedical Circuits and Systems Conference (BioCAS), 2017Co-Authors: Hristos S Courellis, Samuel U Nummela, Cory T Miller, Gert CauwenberghsAbstract:Modern spike sorting techniques are heavily reliant on unsupervised machine learning algorithms for isolation of Single-Unit Activity from noisy channel recordings. One of the most common methods, k-means clustering, is highly sensitive to the number of clusters selected (k) prior to analysis. A robust automated method for determining k is required, in particular for the large datasets currently being analyzed by the Neuroscience commUnity. Information criteria, often applied for this analysis, can yield over-fitted clustering recommendations and employ strong assumptions about cluster gaussianity which do not necessarily hold for real in-vivo neuro-electrophysiological recordings. An algorithmic approach to spike sorting is applied utilizing tandem multi-level wavelet decomposition and principal component analysis to construct a discriminant feature space. K-means clustering is applied to this feature space using a variety of distance metrics to determine which approach yields optimal cluster separation. Clustering outcomes are evaluated using the Entropic Product, an information entropy-based measure that makes no assumptions about the underlying distribution of spikes within a cluster. This measure is demonstrated to be more informative about clustering outcomes than other information criteria when sorting spike data collected using bundled microwire arrays implanted in the Primary Visual Cortex of marmosets conducting a visual-stimulation task.
