Search results for "physiologic"
showing 10 items of 2593 documents
Changes in neuromuscular function after tasks involving control of EMG versus torque feedback of the same duration.
2006
This study was designed to compare alterations in neuromuscular function after two tasks of similar duration involving the control of (1) torque level fixed at 40% maximal voluntary contraction (MVC) torque (torque task) and (2) EMG level when exerting 40% MVC torque on the knee extensor muscles. Ten healthy subjects volunteered to participate in two testing sessions separated by approximately 2 h. Contraction duration for the EMG task was fixed for each subject to the time to task failure of the torque task (104+/-20s). MVC, maximal voluntary activation level, muscle compound action potential (M-wave), peak twitch and potentiated peak doublet were assessed before and immediately after each…
Switching on the deep brain stimulation: effects on cardiovascular regulation and respiration.
2011
Abstract Background Objective of this study was to evaluate the acute cardiovascular and respiratory effects of switching on the deep brain stimulation in the follow up of nine Parkinson's disease patients with subthalamic nucleus stimulation and six cluster headache patients with posterior hypothalamic area stimulation. Methods Systolic and diastolic blood pressure, heart rate, and respiratory rate were monitored continuously during supine rest in both groups. Each patient was assessed in two conditions: resting supine with stimulator off and with stimulator on. Results In supine resting condition switching on the DBS induced no significant changes ( p > 0.05) in systolic and diastolic bl…
Physical Activity Monitoring and Acceptance of a Commercial Activity Tracker in Adult Patients with Haemophilia.
2019
Physical activity (PA) is highly beneficial for people with haemophilia (PWH), however, studies that objectively monitor the PA in this population are scarce. This study aimed to monitor the daily PA and analyse its evolution over time in a cohort of PWH using a commercial activity tracker. In addition, this work analyses the relationship between PA levels, demographics, and joint health status, as well as the acceptance and adherence to the activity tracker. Twenty-six PWH were asked to wear a Fitbit Charge HR for 13 weeks. According to the steps/day in the first week, data were divided into two groups: Active Group (AG
Psychometric properties of non-specific electrodermal response frequency for a sample of male students.
1990
In the present study data on the frequency of non-specific electrodermal responses (NSRs) are presented for a large and, with regard to sex, age and educational level, homogeneous sample of male students (n = 590). These data were obtained in 9 independent experiments in which NSRs were recorded under equivalent conditions. NSRs were scored as skin conductance changes greater than 0.02 muSiemens. A recording period of 5 min prior to experimental manipulations was chosen. A systematic comparison between the 9 studies, the distribution of NSRs for the total sample, as well as descriptive data for stabile and labile subgroups are presented. For 213 subjects NSR-frequency was recorded twice, wi…
Experimental and methodological factors affecting test-retest reliability of amygdala BOLD responses.
2018
Previous studies reported poor to fair test-retest reliability of amygdala BOLD responses to emotional stimuli. However, these findings are very heterogeneous across and within studies. The present study sought to systematically examine experimental and methodological factors that contribute to this heterogeneity. Forty-six young subjects were scanned twice with a mean test-retest interval of 7 weeks. We compared amygdala reliability across three tasks: A face-matching task, passive viewing of emotional faces, and passive viewing of emotional scenes. We also explored whether extraction of physiological noise can affect the stability of amygdala responses. We assessed test-retest reliability…
Circadian gastric acidity in Helicobacter pylori positive ulcer patients with and without gastric metaplasia in the duodenum.
1996
BACKGROUND: The presence of gastric metaplasia allows helicobacter pylori to colonise the duodenum and this condition is thought to be acquired as a response to acid hypersecretion. This functional disorder, however, is present only in a subgroup of duodenal ulcer patients and, in addition, surface gastric metaplasia has been frequently found in the proximal duodenum of normal subjects and patients with non-ulcer dyspepsia, who cannot be certainly considered as acid hypersecretors. AIMS: To clarify the role of acid in inducing gastric type epithelium in the duodenum. This study aimed at assessing whether the pattern of circadian gastric acidity differs between H pylori positive duodenal ulc…
Re-examination of training effects by electrostimulation in the human elbow musculoskeletal system.
2000
This study examines the effects of a 7 weeks sub-maximal training period of electrostimulation on the maximal isometric, concentric, eccentric voluntary torque and muscle contractile properties of the elbow flexor muscles of nine subjects. The daily program consisted of five series of six 6-s isometric actions (60 to 70% of maximal isometric voluntary action) at an elbow angle of 90 . After training the maximal voluntary isometric flexion torque increased significantly whereas the maximal voluntary isometric extension torque decreased significantly. Increases in isometric flexion torque were linked to an increase of the myoelectrical activity of the biceps brachii muscle. Under dynamic cond…
An electrophysiological study of dyslexic and control adults in a sentence reading task.
2002
Event-related potentials and cued-recall performance were used to compare dyslexic and control adult subjects. Sentences that ended either congruously or incongruously were presented visually, one word at a time, at fast (stimulus-onset-asynchrony (SOA)=100 ms) or slow (SOA=700 ms) rates of presentation. Results revealed (1) a large effect of presentation rate that started with the N1-P2 components and lasted for the entire recording period, (2) larger N400 components for dyslexic than control subjects, at slow presentation rates, to both congruous and incongruous endings and (3) a large ERPs difference related to memory (Dm effect) that did not differentiate controls from dyslexics but was…
Prism adaptation and neck muscle vibration in healthy individuals: Are two methods better than one?
2013
Studies involving therapeutic combinations reveal an important benefit in the rehabilitation of neglect patients when compared to single therapies. In light of these observations our present work examines, in healthy individuals, sensorimotor and cognitive after-effects of prism adaptation and neck muscle vibration applied individually or simultaneously. We explored sensorimotor after-effects on visuo-manual open-loop pointing, visual and proprioceptive straight-ahead estimations. We assessed cognitive after-effects on the line bisection task. Fifty-four healthy participants were divided into six groups designated according to the exposure procedure used with each: 'Prism' (P) group; 'Vibra…
Causal relationships in the variability of cardiovascular system evoked by orthostatic stress by transfer entropy.
2015
The coupling between cardiac and vascular systems in healthy volunteers, elicited by the head-up tilt test is estimated by means of transfer entropy with non-uniform embedding. The method applied to beat-to-beat recordings with heart periods and systolic blood pressure, supports the commonly accepted model, that baroreflex is the key factor in maintaining homeostatic blood distribution after tilting. However the method applied to changes of heart periods and changes of blood pressure, display switches in the driving system, from vascular in the early tilt, to cardiac just after the early tilt and back to vascular in the late tilt.