Search results for "Stimulation"
showing 10 items of 2192 documents
The role of the claustrum in the bilateral control of frontal oculomotor neurons in the cat.
1991
The effect of claustrum (CL) stimulation on the spontaneous unitary activity of ipsi and contralateral frontal oculomotor neurons, was studied in chloralose-anaesthetized cats. A total of 205 units was bilaterally recorded in the medial oculomotor area, homologous of the primate "frontal eye fields"; 127 neurons were identified as projecting to the superior colliculus; for 33 of these last units stimulation of the ipsilateral CL provoked an excitatory effect lasting 10-25 ms and appearing with a latency of 5-15 ms; on 8 units the excitatory effect was followed by an inhibition lasting 100-250 ms. Ninety-eight of the 127 neurons were also tested through activation of the contralateral CL: 13…
The course of corticofacial projections in the human brainstem.
2001
Transcranial magnetic stimulation was used to investigate the corticofacial projections in 53 patients with (n = 28) and without (n = 25) central facial paresis due to unifocal ischaemic lesions at different brainstem levels. Lesion topography documented by MRI studies was correlated with the electrophysiological findings. In the majority of patients the corticofacial fibres travel within the ventromedial base of the pons and cross the midline at the level of the facial nucleus. In some individuals, however, we found evidence that corticolingual fibres form an 'aberrant bundle' in a paralemniscal position at the dorsal edge of the pontine base. In other patients the corticofacial fibres loo…
Making Waves: Initiation and Propagation of Corticothalamic Ca2+ Waves In Vivo
2013
Corticothalamic slow oscillations of neuronal activity determine internal brain states. At least in the cortex, the electrical activity is associated with large neuronal Ca(2+) transients. Here we implemented an optogenetic approach to explore causal features of the generation of slow oscillation-associated Ca(2+) waves in the in vivo mouse brain. We demonstrate that brief optogenetic stimulation (3-20 ms) of a local group of layer 5 cortical neurons is sufficient for the induction of global brain Ca(2+) waves. These Ca(2+) waves are evoked in an all-or-none manner, exhibit refractoriness during repetitive stimulation, and propagate over long distances. By local optogenetic stimulation, we …
Rethinking physical and rehabilitation medicine: new technologies induce new learning strategies
2010
International audience; Reeducation consists in training people injured by either illness or the vagaries of life to achieve the best fundionality now possible for them. Strangely, the subject is not taught in the normal educational curricula of the relevant professions. Reeducation thus tends to be developed anew with each patient, without recourse to knowledge of what such training, or assistance in such training, might be. However, new paradigms of reeducation are in fact possible today, thanks to advances in cognitive science and the development of new technologies such as virtual reality and robotics. In turn, they lead to the rethinking of the procedures of physical medicine, as well …
Transcranial Magnetic Stimulation Combined With Nicotine Replacement Therapy for Smoking Cessation: A Randomized Controlled Trial.
2015
Abstract Background Further evidence suggests that repetitive Transcranial Magnetic Stimulation (rTMS) is an effective method to reduce tobacco craving among smokers. Hypothesis As relapse is common within a few days after smoking cessation, we hypothesized that combining the anti-craving effects of rTMS with Nicotine replacement therapy (NRT) to attenuate withdrawal symptoms could increase abstinence rates in smokers with severe nicotine dependence who quit smoking. Methods Thirty-seven smokers who failed to quit with the usual treatments were randomly assigned to two treatment groups to receive either active ( n = 18) or sham ( n = 19) 1-Hz rTMS of the right dorsolateral prefrontal cort…
Neural inflammation alters synaptic plasticity probed by 10 Hz repetitive magnetic stimulation
2020
ABSTRACTSystemic inflammation is associated with alterations in complex brain functions such as learning and memory. However, diagnostic approaches to functionally assess and quantify inflammation-associated alterations in synaptic plasticity are not well-established. In previous work, we demonstrated that bacterial lipopolysaccharide (LPS)-induced systemic inflammation alters the ability of hippocampal neurons to express synaptic plasticity, i.e., the long-term potentiation (LTP) of excitatory neurotransmission. Here, we tested whether synaptic plasticity induced by repetitive magnetic stimulation (rMS), a non-invasive brain stimulation technique used in clinical practice, is affected by L…
A current source density analysis of field potentials evoked in slices of visual cortex
1987
The method of one-dimensional current source density (CSD) analysis was applied to field potentials recorded from 350 microns thick slices of the primary visual cortex of rats and cats. Field potentials were elicited by stimulation of the white matter and recorded along trajectories perpendicular to the cortical layers at spatial intervals of 25 to 50 microns. The resulting CSD distributions resembled closely those recorded from the cat visual cortex "in vivo". The responses with the shortest latency were distinct sinks in layers IV and VI probably reflecting monosynaptic EPSP's from specific thalamic afferents. From layer IV activity was relayed along three major routes: 1. to the supragra…
Vesicular Storage and Release of Cholinergic False Transmitters
1979
Publisher Summary Several analogues of choline are known, which are taken up by cholinergic nerve terminals and released in the acetylated form on stimulation. Such compounds are thus precursors of cholinergic false transmitters. This chapter discusses two compounds, N-methyl-N-2-hydroxyethylpyrrolidiniu (mPCh) and homocholine (HCh), using guinea-pig cortex and the electric organ of Torpedo marmorata. In the experiments with cortex, the false transmitter precursors were injected into the tissue and released transmitters collected in Locke solution applied to the surface of the cortex in plastic sleeves. Free vesicles and those attached to external membranes were isolated from tissue subjace…
The Uptake of Acetylpyrrolidinecholine — A False Cholinergic Transmitter — Into Mammalian Cerebral Cortical Synaptic Vesicles
1978
It is now well established that cholinergic vesicles are metabolically heterogeneous organelles. It is, however, still under discussion whether this is due to an intravesicular or an intervesicular heterogeneity. March-banks and Israel (10), supporting the hypothesis of intravesicular heterogeneity, suggested that newly formed ACh is only loosely bound to the vesicles. On the other hand, a distinct vesicle fraction obtained from the electromotor system of Torpedo marmorata after its incubation with radioisotopes shows a high specific radioactivity (12), results which favor the view that intervesicular differences do exist. Biochemical and morphological findings suggest that these vesicles h…