The Experts below are selected from a list of 243 Experts worldwide ranked by ideXlab platform
George V. Rebec - One of the best experts on this subject based on the ideXlab platform.
-
Real-time assessments of dopamine function during behavior: Single-Unit Recording, iontophoresis, and fast-scan cyclic voltammetry in awake, unrestrained rats.
Alcoholism clinical and experimental research, 1998Co-Authors: George V. RebecAbstract:Although ample evidence implicates the dopamine (DA) projection to the neostriatum and nucleus accumbens in motor and motivational processes, relatively little information is available on how DA alters neostriatal or accumbal functions under naturally occurring behavioral conditions. Further insight into neuron-behavior relationships can be achieved with the application of Single-Unit Recording techniques, including iontophoresis and fast-scan cyclic voltammetry (FSCV), to awake, unrestrained animals. Single-Unit Recording has revealed that amphetamine, a widely abused psychomotor stimulant, activates motor-, but inhibits nonmotor-related neurons in neostriatum and nucleus accumbens. Although either response can be blocked by DA receptor antagonists, the amphetamine-induced activation also depends on an intact corticostriatal system, suggesting a role for glutamate (GLU). Both neostriatal and accumbal neurons are sensitive to iontophoretic application of either DA or GLU, but when applied during low-dose application of DA, the GLU signal is enhanced relative to background activity. In effect, DA appears to modulate GLU by strengthening the GLU signal-to-noise ratio. To assess DA release under behaviorally relevant conditions, FSCV has been used to obtain real-time measurements of DA efflux in a free-choice novelty test. DA efflux increased only during the brief period of entry into novelty, and the increase was confined to accumbal shell and the shell-core transition zone, the so-called shore. Neither accumbal core nor the overlying neostriatum showed a novelty-related DA change. Thus, DA release during behavior is not uniform and in the case of novelty appears targeted to the limbic-related area of accumbal shell. Further application of these and other in vivo technologies to ambulant animals is required to identify the complex mechanisms underlying both the release of DA and its effect on neostriatal and accumbal neurons during behavior.
-
Heterogeneity of ventral tegmental area neurons: Single-Unit Recording and iontophoresis in awake, unrestrained rats.
Neuroscience, 1998Co-Authors: Eugene A. Kiyatkin, George V. RebecAbstract:Single-Unit Recording combined with iontophoresis of dopamine, GABA, and glutamate was used in awake, unrestrained rats to characterize the electrophysiological and receptor properties of neurons in the ventral tegmental area under naturally occurring behavioural conditions. All isolated ventral tegmental area units (n=90) were analysed and compared with cells (n=58) recorded from dorsally adjacent areas of the pre-rubral area and red nucleus. Two distinct neuronal groups were identified in the ventral tegmental area: units with triphasic, long-duration spikes (78/90) and units with biphasic, short-duration spikes (12/90). Although all long-spike units discharged in an irregular, bursting pattern with varying degrees of within-burst decrements in spike amplitude, they could be further subdivided into at least three distinct subgroups. Type I long-spike units (36/78) discharged at a relatively slow and stable rate (mean: 6.03 imp/s; range: 0.42–15.78) with no evident fluctuations during movement. These cells were inhibited by dopamine and GABA and responded to glutamate with a low-magnitude excitation accompanied by a pronounced decrement in spike amplitude and a powerful rebound inhibition. Type II long-spike units (23/78) had relatively high and unstable discharge rates (mean: 22.82 imp/s; range: 4.42–59.67) and showed movement-related phasic activations frequently followed by partial or complete cessation of firing. Some Type II cells (4/9) were inhibited by dopamine, but all were excited by glutamate at very low currents (0–10 nA). With an increase in current, the glutamate-induced excitation often (18/22) progressed into a cessation of firing. All these cells were inhibited by GABA followed by a strong rebound excitation (8/9), which also frequently (6/8) resulted in cessation of firing. Type III long-spike units (19/78) had properties that differed from either Type I or Type II cells, including a lack of spontaneous firing (5/19). Short-spike ventral tegmental area units were either silent (4/12) and unresponsive to dopamine and GABA or spontaneously active (range: 0.89–34.13 imp/s) and inhibited by GABA and, in some cases (2/8), by dopamine; all were phasically activated during movement and glutamate iontophoresis. It appears that ventral tegmental area neurons, including those with long-duration spikes, do not comprise a uniform population in awake, unrestrained rats. Type I, long-spike units match the characteristics of histochemically-identified dopamine neurons, and they appear to express dopamine autoreceptors, which may explain the relatively slow, stable rate of activity and the limited responsiveness to excitatory inputs. Although the nature of the other long-spike units in our sample is unclear, they may include dopamine neurons without autoreceptors as well as non-dopamine cells. The heterogeneity of ventral tegmental area neurons is an important consideration for further attempts to assess the role of the mesocorticolimbic dopamine system in motivated behaviour.
Peng Han - One of the best experts on this subject based on the ideXlab platform.
-
The head fixation based on skull cap: An improved protocol used in single unit Recording in the vestibular system.
MethodsX, 2020Co-Authors: Pengyu Ren, Shiyao Dong, Boqiang Lyu, Shouping Gong, Qing Zhang, Peng HanAbstract:Abstract Single unit Recording has an important application in neuroscience, especially in the vestibular system such as visual stabilization, posture maintenance, spatial orientation and cognition. However, single unit Recording conducted in living animals is a demanding technique and non-ideal mechanical stability between the Recording location of nerve tissues and the tip of microelectrode always results in failure to obtain successful Recordings in the vestibular system. In order to improve the mechanical stability during single unit Recording, we constructed a novel head fixation method based on skull cap. This article describes in detail how to construct this novel head fixation. Following the step-by-step procedure mentioned in this article will provide a high-quality mechanical stability for single unit Recording in the vestibular system, allowing us to successfully record the nonlinear neural dynamic response over a big magnitude motion stimulation. This improvement of head fixation contributes to the in-depth understanding of the vestibular system.
-
improvement of mechanical stability for single unit Recording based on skull cap in living chinchilla
Current medical science, 2019Co-Authors: Pengyu Ren, Shiyao Dong, Peng HanAbstract:Three-point head fixation was constructed to provide mechanical stability for single unit Recording (SUR) on vestibular sensory system in living chinchilla previously. However, it is no more qualified to this work when the stimulation intensity becomes large because of frequent unit losing and neuron damage, which strongly implies that the mechanical stability has been broken during the stimulation. Here, we constructed a novel head fixation (skull cap assistant head fixation) provided by skull cap on the basis of three-point head fixation in order to improve the mechanical stability for SUR under the stimulation with large magnitude. The large area bone connection is the feature and advantage of this improved method, which directly fixes the tested local nervous tissue and microelectrode in an intact stable system through skull cap except two ear bars and a tube face mask. Our data exhibited that skull cap assistant head fixation could significantly improve the success rate of neural response activity Recording in the population of semicircular canal neurons under the stimulation with large intensity (amplitude ≥100 deg/s). Based on the analysis of neural response activity and noise base-line during stimulation, our data further indicated that this method could significantly improve the mechanical stability for SUR during high-speed motion stimulation on vestibular system in living chinchilla. Skull cap assistant head fixation extends the application of SUR on vestibular neuron in linear response range and provides a solid foundation for electrophysiological research on vestibular sensory system in further studies.
Kazuya Sakai - One of the best experts on this subject based on the ideXlab platform.
-
What Single-Unit Recording studies tell us about the basic mechanisms of sleep and wakefulness
The European journal of neuroscience, 2019Co-Authors: Kazuya SakaiAbstract:This paper reviews the presence, localization and characteristics of state-specific neurons in the mouse forebrain, midbrain and hindbrain that are involved in the control of ultradian sleep-wake cycles and shows that all these regions contain basic neural elements capable of generating the sleep-wake cycle. The chronic Single-Unit Recording method in unanaesthetized animals is useful for unravelling the dynamics of sleep-wake switching, in particular because it can analyse events at the level of single neurons, thereby decoding information used by the brain in determining its functional state. A prerequisite is to record a large number of all types of neurons, identify critical wake- and sleep-promoting neurons and determine their activity profiles during the sleep-wake cycle and their trends in spike activity during the state transitions from wakefulness to sleep and from sleep to wakefulness in the same species. Here, I argue that Single-Unit Recordings in unanaesthetized mice help us to (a) determine key neural elements controlling sleep-wake dynamics, (b) elucidate the roles of forebrain and brainstem neurons in ultradian sleep-wake cyclicity and (c) gain a new insight into the functional significance of wakefulness, slow-wave sleep and paradoxical (or rapid eye movement) sleep. I also discuss the merits and limitations of Single-Unit Recording compared with more recent genetic approaches, and I suggest that findings from studies using the classic electrophysiological technique will provide the foundation for future studies using new genetic techniques to dissect the neural networks responsible for the initiation, maintenance and cessation of each wake and sleep state.
-
A potent non-monoaminergic paradoxical sleep inhibitory system: a reverse microdialysis and Single-Unit Recording study.
The European journal of neuroscience, 2006Co-Authors: Sylvain Crochet, Hirotaka Onoe, Kazuya SakaiAbstract:Using reverse microdialysis and polygraphic Recordings in freely moving cats, we investigated the effects on sleep-waking states of application of excitatory and inhibitory amino acid agonists, cholinergic agonist and monoamines to the periaqueductal grey and adjacent mesopontine tegmentum. Single-Unit Recordings during behavioural states were further used to determine the neuronal characteristics of these structures. We found that muscimol, a GABAA receptor agonist, induced a significant increase in paradoxical sleep (PS) only when applied to a dorsocaudal central tegmental field (dcFTC) located just beneath the ventrolateral periaqueductal grey. In this structure, both kainic and N-methyl-aspartic acids caused a dose-dependent increase in wakefulness (W) and decrease in both slow-wave sleep (SWS) and PS. Norepinephrine and epinephrine, and to a lesser extent histamine, also increased W and decreased SWS and PS, whereas serotonin, dopamine and carbachol, a cholinergic agonist, had no effect. Two types of neurones were recorded in this structure, those exhibiting a higher rate of tonic discharge during both W and PS compared with during SWS, and those showing a phasic increase in firing rate during both active W and PS. Both types of neurones showed a gradual increase in unit activity during PS. Our study demonstrated for the first time that the ventrolateral periaqueductal grey and dcFTC play different roles in behavioural state control, that the dcFTC neurones are critically involved in the inhibitory mechanisms of PS generation, playing a central part in its maintenance, and that these neurones are under the control of GABAergic, glutamatergic, adrenergic and histaminergic systems.
Pengyu Ren - One of the best experts on this subject based on the ideXlab platform.
-
The head fixation based on skull cap: An improved protocol used in single unit Recording in the vestibular system.
MethodsX, 2020Co-Authors: Pengyu Ren, Shiyao Dong, Boqiang Lyu, Shouping Gong, Qing Zhang, Peng HanAbstract:Abstract Single unit Recording has an important application in neuroscience, especially in the vestibular system such as visual stabilization, posture maintenance, spatial orientation and cognition. However, single unit Recording conducted in living animals is a demanding technique and non-ideal mechanical stability between the Recording location of nerve tissues and the tip of microelectrode always results in failure to obtain successful Recordings in the vestibular system. In order to improve the mechanical stability during single unit Recording, we constructed a novel head fixation method based on skull cap. This article describes in detail how to construct this novel head fixation. Following the step-by-step procedure mentioned in this article will provide a high-quality mechanical stability for single unit Recording in the vestibular system, allowing us to successfully record the nonlinear neural dynamic response over a big magnitude motion stimulation. This improvement of head fixation contributes to the in-depth understanding of the vestibular system.
-
improvement of mechanical stability for single unit Recording based on skull cap in living chinchilla
Current medical science, 2019Co-Authors: Pengyu Ren, Shiyao Dong, Peng HanAbstract:Three-point head fixation was constructed to provide mechanical stability for single unit Recording (SUR) on vestibular sensory system in living chinchilla previously. However, it is no more qualified to this work when the stimulation intensity becomes large because of frequent unit losing and neuron damage, which strongly implies that the mechanical stability has been broken during the stimulation. Here, we constructed a novel head fixation (skull cap assistant head fixation) provided by skull cap on the basis of three-point head fixation in order to improve the mechanical stability for SUR under the stimulation with large magnitude. The large area bone connection is the feature and advantage of this improved method, which directly fixes the tested local nervous tissue and microelectrode in an intact stable system through skull cap except two ear bars and a tube face mask. Our data exhibited that skull cap assistant head fixation could significantly improve the success rate of neural response activity Recording in the population of semicircular canal neurons under the stimulation with large intensity (amplitude ≥100 deg/s). Based on the analysis of neural response activity and noise base-line during stimulation, our data further indicated that this method could significantly improve the mechanical stability for SUR during high-speed motion stimulation on vestibular system in living chinchilla. Skull cap assistant head fixation extends the application of SUR on vestibular neuron in linear response range and provides a solid foundation for electrophysiological research on vestibular sensory system in further studies.
Peter N. Steinmetz - One of the best experts on this subject based on the ideXlab platform.
-
In situ Single-Unit Recording of hypothalamic hamartomas under endoscopic direct visualization.
Neurosurgery, 2009Co-Authors: Gregory P. Lekovic, John F. Kerrigan, Scott D. Wait, Harold L. Rekate, Peter N. SteinmetzAbstract:OBJECTIVE: Hypothalamic hamartomas (HHs) are associated with refractory epilepsy and are amenable to surgical treatment. The gelastic seizures associated with HHs originate within the HH lesion, but the responsible cellular mechanisms are unknown. Microelectrode patch-clamp Recordings from HH neurons in resected slice preparations show that small HH neurons spontaneously fire with intrinsic pacemaker-like activity. We questioned whether spontaneous firing of HH neurons was present in situ, and we hypothesized that Single-Unit field Recordings from HH tissue could be obtained with instrumentation passed through the endoscope before surgical resection. TECHNIQUE: After informed consent was obtained, patients undergoing transventricular, endoscopic resection of an HH for intractable epilepsy were eligible for study. After placement of the endoscope, a bundled microwire (total of 9 contacts) was placed into the HH under direct visualization. Spontaneous activity was recorded for two or three 5-minute epochs, under steady-state general anesthesia. The wire was advanced 0.5 to 1 mm within the lesion between Recording epochs. RESULTS: A total of thirteen 5-minute Recordings were obtained from 5 patients. Noise levels were comparable to extraoperative microwire Recordings for temporal lobe epilepsy. Single-neuron spike activity was isolated from a total of 5 channels obtained during Recording of 3 sessions in 3 patients. CONCLUSION: We have shown that Single-Unit Recordings from HH lesions can be successfully obtained in situ under direct endoscopic visualization. We believe that this is the first report using the working channel of a neuroendoscope to make physiological Recordings of deep structures in humans.
-
In situ Single-Unit Recording of hypothalamic hamartomas under endoscopic direct visualization.
Neurosurgery, 2009Co-Authors: Gregory P. Lekovic, John F. Kerrigan, Harold L. Rekate, Scott Wait, Peter N. SteinmetzAbstract:Hypothalamic hamartomas (HHs) are associated with refractory epilepsy and are amenable to surgical treatment. The gelastic seizures associated with HHs originate within the HH lesion, but the responsible cellular mechanisms are unknown. Microelectrode patch-clamp Recordings from HH neurons in resected slice preparations show that small HH neurons spontaneously fire with intrinsic pacemaker-like activity. We questioned whether spontaneous firing of HH neurons was present in situ, and we hypothesized that Single-Unit field Recordings from HH tissue could be obtained with instrumentation passed through the endoscope before surgical resection. After informed consent was obtained, patients undergoing transventricular, endoscopic resection of an HH for intractable epilepsy were eligible for study. After placement of the endoscope, a bundled microwire (total of 9 contacts) was placed into the HH under direct visualization. Spontaneous activity was recorded for two or three 5-minute epochs, under steady-state general anesthesia. The wire was advanced 0.5 to 1 mm within the lesion between Recording epochs. A total of thirteen 5-minute Recordings were obtained from 5 patients. Noise levels were comparable to extraoperative microwire Recordings for temporal lobe epilepsy. Single-neuron spike activity was isolated from a total of 5 channels obtained during Recording of 3 sessions in 3 patients. We have shown that Single-Unit Recordings from HH lesions can be successfully obtained in situ under direct endoscopic visualization. We believe that this is the first report using the working channel of a neuroendoscope to make physiological Recordings of deep structures in humans.
