Search results for "Stimulation"
showing 10 items of 2192 documents
A Kinetic Model of Short- and Long-Term Potentiation
1993
We present a kinetic model that can account for several experimental findings on short- and long-term potentiation (STP and LTP) and their pharmacological modulation. The model, which is consistent with Hebb's postulate, uses the hypothesis that part of the origin of LTP may be a consequence of an increased release of neurotransmitter due to a retrograde signal. The operation of the model is expressed by a set of irreversible reactions, each of which should be thought of as equivalent to a set of more complex reactions. We show that a retrograde signal alone is not sufficient to maintain LTP unless long-term change of the rate constant of some of the reactions is caused by high-frequency s…
Severe Perinatal Hypoxic-Ischemic Brain Injury Induces Long-Term Sensorimotor Deficits, Anxiety-Like Behaviors and Cognitive Impairment in a Sex-, Ag…
2019
Perinatal brain injury (PBI) leads to neurological disabilities throughout life, from motor deficits, cognitive limitations to severe cerebral palsy. Yet, perinatal brain damage has limited therapeutic outcomes. Besides, the immature brain of premature children is at increased risk of hypoxic/ischemic (HI) injury, with males being more susceptible to it and less responsive to protective/therapeutical interventions. Here, we model in male and female C57BL/6 mice, the impact of neonatal HI and the protective effects of neonatal handling (NH), an early life tactile and proprioceptive sensory stimulation. From postnatal day 1 (PND1, modeling pre-term) to PND21 randomized litters received either…
Von Willebrand-Syndrom - Blutungsrisiko bei HNO-Eingriffen im Kindesalter
1994
Von Willebrand's disease (vWD) is the most common inherited bleeding disorder. Typical clinical features such as bleeding after surgery or trauma might suggest the disease. We present a series of 24 patients with vWD treated between 1989 and 1992. Diagnosis was confirmed by a reduction in plasma factor VIII antigen concentration, reduction of ristocetin cofactor activity and reduced factor VIII activity. Seventeen of the patients underwent surgery (7 adenoidectomies, 8 tonsillectomies, 2 paranasal sinus operations) and received preoperative stimulation of von Willebrand factor (vWF) using DDAVP. This resulted in a rapid increase in plasma vWF concentration from an average of 56% before stim…
Effects of electrical stimulation pattern on quadriceps isometric force and fatigue in individuals with spinal cord injury
2015
Introduction Variable frequency trains (VFT) or train combinations have been suggested as useful strategies to offset the rapid fatigue induced by constant frequency trains (CFT) during electrical stimulation. However, most studies have been of short duration with limited functional application in those with spinal cord injury (SCI). We therefore tested force and fatigue in response to VFT, CFT, and combined patterns in strength training-like conditions (6-s contractions). Methods Ten SCI individuals underwent either CFT or VFT patterns until target torque was no longer produced and then switched immediately to the other pattern. Results Target torque was reached more times when VFT was use…
The Effect of the Cranial Electrotherapy on the Muscle Motor Function in Different Operating Modes
2015
The aim of the present study was to analyze the effect of cranial electrotherapy stimulation on muscle function analysis indicators. Instrumental assessment of muscle function (on a REV9000, Technogym, Italy) was performed before and after cranial electrotherapy stimulation, assessments of the muscle function was performed during knee extension maximum voluntary, isometric contraction (MVIC), angle velocity with load 45Nm isotonic contraction and maximum pick torque in isokinetic contraction on 30°/s, 200°/s and 300°/s and neuromuscular efficiency measurements. To analyze data was used Excel program Statistics 3.1. Subjects of our study were twenty healthy athletes of sport fitness. 1 minu…
Effects of Transcranial Direct Current Stimulation on Brain Networks Related to Creative Thinking
2020
AbstractHuman creative thinking is unique and capable of generating novel and valuable ideas. Recent research has clarified the contribution of different brain networks (default mode network, DN; executive control network; salience network) to creative thinking. However, the effects of brain stimulation on brain networks during creative thinking and on creative performance have not been clarified. The present study was designed to examine the changes in functional connectivity (FC) and effective connectivity (EC) of the large-scale brain network, and the ensuing changes in creative performance, induced by transcranial direct current stimulation (tDCS). Fourteen healthy male students underwe…
TRANSCRANICAL MAGNETIC STIMULATION IN COCAINE ADDICTION:PRELIMINARY FINDINGS
2014
Drug addiction is a brain disease which leads to profound disturbances in an individual’s behaviour. In spite of the progress made in the understanding of the neurobiological mechanisms underlying addiction, expectations from a therapeutic point of view have not been satisfying. Given the modest efficacy of therapeutic tools available, Transcranial Magnetic Stimulation (TMS) seems to be a promising “non-pharmacologic” aid in various neuropathologies including addiction which is characterized by a decrease of dopaminergic activity (DA). Thus, ‘restoring’ pre-pathology DA activity may yield clinical benefits in addicts. In particular, it has been reported that TMS reduces the craving for coca…
Hippocampal electrical stimulation disrupts associative learning when targeted at dentate spikes
2017
Hippocampal electrophysiological oscillations, namely theta and ripples, have been implicated in encoding and consolidation of new memories, respectively. According to existing literature, hippocampal dentate spikes are prominent, short‐duration (<30 ms), large‐amplitude (∼2–4 mV) fluctuations in hilar local‐field potentials that take place during awake immobility and sleep. Interestingly, previous studies indicate that during dentate spikes dentate gyrus granule cells increase their firing while firing of CA1 pyramidal cells are suppressed, thus resulting in momentary uncoupling of the two hippocampal subregions. To date, the behavioural significance of dentate spikes is unknown. Here, to …
Examinations of Bilateral Epileptiform Activities in Hippocampal Slices Obtained From Young Mice
2021
Bilateral interconnections through the hippocampal commissure play important roles in synchronizing or spreading hippocampal seizure activities. Intact hippocampi or bilateral hippocampal slices have been isolated from neonatal or immature rats (6–7 or 12–21 days old, respectively) and the mechanisms underlying the bilateral synchrony of hippocampal epileptiform activities have been investigated. However, the feasibility of examining bilateral epileptiform activities of more developed hippocampal circuitryin vitroremains to be explored. For this, we prepared bilateral hippocampal slices from C57 black mice, a strain commonly used in neuroscience and for genetic/molecular modifications. Youn…
Dysfunction of the mesolimbic circuit to food odors in women with anorexia and bulimia nervosa: A fMRI study
2019
Brain reward dysfunction in eating disorders has been widely reported. However, whether the neural correlates of hedonic and motivational experiences related to food cues are differentially affected in anorexia nervosa of restrictive type (ANr), bulimia nervosa (BN), and healthy control (HC) participants remains unknown. Here, 39 women (14 ANr, 13 BN, and 12 HC) underwent fMRI while smelling food or non-food odors in hunger and satiety states during liking and wanting tasks. ANr and BN patients reported less desire to eat odor-cued food and odor-cued high energy-density food (EDF), respectively. ANr patients exhibited lower ventral tegmental area (VTA) activation than BN patients to food od…