Search results for "STIMULATION"
showing 10 items of 2192 documents
The limits of visual mass perception
2009
The theory of direct perception suggests that observers can accurately judge the mass of a box picked up by a lifter shown in a point-light display. However, accurate perceptual performance may be limited to specific circumstances. The purpose of the present study was to systematically examine the factors that determine perception of mass, including display type, lifting speed, response type, and lifter's strength. In contrast to previous research, a wider range of viewing manipulations of point-light display conditions was investigated. In Experiment 1, we first created a circumstance where observers could accurately judge lifts of five box masses performed by a lifter of average strength…
Does Observation of Postural Imbalance Induce a Postural Reaction?
2011
Import JabRef | WosArea Life Sciences and Biomedicine - Other Topics; International audience; Background: Several studies bring evidence that action observation elicits contagious responses during social interactions. However automatic imitative tendencies are generally inhibited and it remains unclear in which conditions mere action observation triggers motor behaviours. In this study, we addressed the question of contagious postural responses when observing human imbalance. Methodology/Principal Findings: We recorded participants' body sway while they observed a fixation cross (control condition), an upright point-light display of a gymnast balancing on a rope, and the same point-light di…
A Two-Phase Model of Resource Allocation in Visual Working Memory
2017
Two broad theories of visual working memory (VWM) storage have emerged from current research, a discrete slot-based theory and a continuous resource theory. However, neither the discrete slot-based theory or continuous resource theory clearly stipulates how the mental commodity for VWM (discrete slot or continuous resource) is allocated. Allocation may be based on the number of items via stimulus-driven factors, or it may be based on task demands via voluntary control. Previous studies have obtained conflicting results regarding the automaticity versus controllability of such allocation. In the current study, we propose a two-phase allocation model, in which the mental commodity could be al…
Unconscious integration of multisensory bodily inputs in the peripersonal space shapes bodily self-consciousness
2017
International audience; Recent studies have highlighted the role of multisensory integration as a key mechanism of self-consciousness. In particular, integration of bodily signals within the peripersonal space (PPS) underlies the experience of the self in a body we own (self-identification) and that is experienced as occupying a specific location in space (self-location), two main components of bodily self-consciousness (BSC). Experiments investigating the effects of multisensory integration on BSC have typically employed supra-threshold sensory stimuli, neglecting the role of unconscious sensory signals in BSC, as tested in other consciousness research. Here, we used psychophysical techniq…
4-Hydroxynonenal, a lipid peroxidation product, induces relaxation of human cerebral arteries.
1994
The relaxant effect of 4-hydroxynonenal (4-HNE), a lipid peroxidation product, on human cerebral arteries was studied. Addition of 4-HNE to artery rings promoted no contraction, and after stimulation with prostaglandin F2α (PFG2α; 10−7-3 × 10−6 M), 100% relaxation was obtained with 3 × 10−5 M 4-HNE. Inhibition of nitric oxide formation with NG-nitro-l-arginine methyl ester hydrochloride (l-NAME; (10−4 M), as well as prostaglandin synthesis with indomethacin (3 × 10−6 M), partially prevented 4-HNE-induced relaxation, but each of these substances separately failed to inhibit complete relaxation. Addition of both inhibitors together reduced 4-HNE-induced relaxation to ≈50%, but relaxation cou…
A repetitive intracortical microstimulation pattern induces long-lasting synaptic depression in brain slices of the rat primary somatosensory cortex.
2000
Repetitive intracortical microstimulation (ICMS) applied to the rat primary somatosensory cortex (SI) in vivo was reported to induce reorganization of receptive fields and cortical maps. The present study was designed to exam- ine the effect of such an ICMS pattern applied to layer IV of brain slices containing SI on the efficacy of synaptic in- put to layer II/III. Effects of ICMS on the synaptic strength was quantified for the first synaptic component ( s1) of cor- tical field potentials (FPs) recorded from layer II/III of SI. FPs were evoked by stimulation in layer IV. The pattern of ICMS was identical to that used in vivo. However, stimula- tion intensity had to be raised to induce an a…
The superoxide anion is involved in the induction of long-term potentiation in the rat somatosensory cortex in vitro.
2004
Abstract The involvement of the superoxide anion (O2−) in the induction of neocortical long-term potentiation (LTP) was examined in rat brain slices containing the primary somatosensory cortex. Field potentials evoked by stimulation in cortical layer IV were recorded from layer II/III. In control experiments, tetanic high-frequency stimulation (HFS) resulted in essentially input-specific, NMDA receptor-dependent LTP (20.2±3.0% increase in field potential amplitude). When the availability of intracellular O2− was reduced by application of the cell membrane-permeable O2− scavengers MnTBAP or CP-H (spin trap), HFS-induced LTP was attenuated to 12.0±1.7% and 8.7±3.1% increase, respectively. In …
The association of noise sensitivity with music listening, training, and aptitude
2015
After intensive, long-term musical training, the auditory system of a musician is specifically tuned to perceive musical sounds. We wished to find out whether a musician's auditory system also develops increased sensitivity to any sound of everyday life, experiencing them as noise. For this purpose, an online survey, including questionnaires on noise sensitivity, musical background, and listening tests for assessing musical aptitude, was administered to 197 participants in Finland and Italy. Subjective noise sensitivity (assessed with the Weinstein's Noise Sensitivity Scale) was analyzed for associations with musicianship, musical aptitude, weekly time spent listening to music, and the impo…
Effectiveness of Pulsed Radiofrequency with Multifunctional Epidural Electrode in Chronic Lumbosacral Radicular Pain with Neuropathic Features
2014
Lumbosacral radicular pain is a common clinical finding with a statistical prevalence ranging from 9.9% to 25% in the general population.To investigate the effectiveness of dorsal root ganglion pulsed radiofrequency (PRF) in patients with chronic lumbosacral radicular pain and neuropathic features.Prospective case series clinical outcome study.We evaluated 34 patients with lumbosacral neuropathic pain who underwent PRF at the corresponding level of radicular symptoms distribution (ranging from L3 to S1). Each patient suffered a single leg-radiating pain with probable neuropathic features (assessed with clinical grading) lasting for6 months and unresponsive to previous treatments. A multifun…
Strength training in old age: adaptation of antagonist muscles at the ankle joint.
2005
The purpose of this study was to determine whether strength training could reduce the deficit in plantarflexion (PF) maximal voluntary contraction (MVC) torque observed in previous studies in older subjects relative to young adults. Accordingly, the effects of a 6-month strength training program on the muscle and neural properties of the major muscle groups around the ankle were examined. PF and dorsiflexion (DF) isometric MVC torques were measured and surface electromyographic activity of the triceps surae and tibialis anterior muscles was recorded. The strength training program was very effective in improving strength in PF (+24.5%), and it thus reduced the DF-to-PF MVC torque ratio; in a…