Search results for " Control"
showing 10 items of 7691 documents
Effects of ageing on motor unit activation patterns and reflex sensitivity in dynamic movements.
2009
Both contraction type and ageing may cause changes in H-reflex excitability. H reflex is partly affected by presynaptic inhibition that may also be an important factor in the control of MU activation. The purpose of the study was to examine age related changes in H-reflex excitability and motor unit activation patterns in dynamic and in isometric contractions. Ten younger (YOUNG) and 13 elderly (OLD) males performed isometric (ISO), concentric (CON) and eccentric (ECC) plantarflexions with submaximal activation levels (20% and 40% of maximal soleus surface EMG). Intramuscular EMG data was analyzed utilizing an intramuscular spike amplitude frequency histogram method. Average H/M ratio was a…
Stroop task performance across the lifespan: High cognitive reserve in older age is associated with enhanced proactive and reactive interference cont…
2020
Abstract Susceptibility to interference increases with age but there is large inter-individual variability in interference control in older adults due to a number of biological and environmental factors. The present study aims at analyzing behavior and ERPs in a Stroop interference task with increasing difficulty in a sample of 246 young, middle-aged and healthy old participants. The old age group was divided into three subgroups based on performance scores. The results show a gradual performance reduction with increasing age and task difficulty. However, old high performers reached a performance level comparable to middle-aged subjects. The contingent negative variation (CNV) reflecting pr…
Lower limb muscle weakness predicts use of a multiple- versus single-step strategy to recover from forward loss of balance in older adults.
2012
BACKGROUND: Older adults compared with young adults have reduced strength and balance recovery ability. The purpose of the present study was to investigate whether age, sex, and/or lower limb strength predicted the stepping strategy used to recover from a forward loss of balance. METHODS: Ninety-five, community-dwelling, older adults, aged 65-90 years, participated in the study. Loss of balance was induced by releasing participants from a static forward lean. Participants performed four trials at three initial lean magnitudes and were subsequently classified as using a single- or multiple-step strategy. Isometric strength of the ankle, knee, and hip joint flexors and extensors was assessed …
Effect of caffeine on simulator flight performance in sleep-deprived military pilot students.
2007
Caffeine has been suggested to act as a countermeasure against fatigue in military operations. In this randomized, double-blind, placebo-controlled study, the effect of caffeine on simulator flight performance was examined in 13 military pilots during 37 hours of sleep deprivation. Each subject performed a flight mission in simulator four times. The subjects received either a placebo (six subjects) or 200 mg of caffeine (seven subjects) 1 hour before the simulated flights. A moderate 200 mg intake of caffeine was associated with higher axillary temperatures, but it did not affect subjectively assessed sleepiness. Flight performance was similar in both groups during the four rounds flown und…
Alcohol Consumption in HealthyOPRM1G Allele Carriers and Its Association with Impulsive Behavior
2015
AIMS: A link between alcohol use disorders (AUD) and impulsivity is well established. As there is evidence for the heritability of AUD, the investigation of the underlying genetic disposition for both conditions is an important issue. An association between AUD and a coding single nucleotide polymorphism (SNP) (rs1799971 encoding an Asn40Asp amino acid substitution, A118G) within the µ-opioid receptor 1 gene (OPRM1) has been reported. Therefore we tested the association between the OPRM1 A118G polymorphism and drinking as well as impulsive behavior in social drinkers. METHODS: A total of 214 healthy male social drinkers were recruited. Each participant was genotyped for the OPRM1 A118G vari…
Influence of information concerning a computerized anesthesia system on dental anxiety: a randomized controlled clinical trial
2020
Background A single-blinded randomized controlled trial among patients requiring an upper third molar extraction was performed to evaluate the anxiety degree after receiving information or not about the functioning of The Wand system. Secondarily, perceived pain and the need of re-anesthesia were assessed. Material and Methods Patients were randomly assigned to the experimental group (detailed explanation about The Wand) or control group (no specific information). Local anesthesia with The Wand consisted in a supraperiosteal infiltrative technique injection 1.6 mL at the buccal and 0.2 mL at the palatal side. Distinct questionnaires for assessing dental anxiety and 100-mm visual analog scal…
Adjuvant vs. neoadjuvant radiochemotherapy for locally advanced rectal cancer: the German trial CAO/ARO/AIO-94.
2003
Aim The standard treatment for patients with clinically resectable rectal cancer is surgery. Postoperative radiochemotherapy (RCT) is recommended for advanced disease (pT3/4 or pN+). In recent years, encouraging results of pre-operative radiotherapy have been reported. This prospective randomized phase-III-trial (CAO/ARO/AIO-94) compares the efficacy of neoadjuvant RCT to standard postoperative RCT. We report on the design of the study and first results with regard to toxicity of RCT and postoperative morbidity. Patients and methods Patients with locally advanced operable rectal cancer (uT3/4 or uN+, Mason CS III/IV) were randomly assigned to pre or postoperative RCT: A total dose of 50.4…
Reduction of low-density lipoprotein cholesterol in patients with coronary heart disease and metabolic syndrome: analysis of the Treating to New Targ…
2006
BACKGROUND: Despite the prognostic value of metabolic syndrome for predicting cardiovascular events, few trials have investigated the effects of statin therapy on cardiovascular morbidity and mortality in patients with the metabolic syndrome. Our post hoc analysis of the Treating to New Targets (TNT) study assessed whether intensive lowering of low-density lipoprotein cholesterol with high-dose atorvastatin therapy results in cardiovascular benefits for patients with both coronary heart disease and the metabolic syndrome. METHODS: The TNT study was a prospective, double blind, parallel-group trial done at 256 sites in 14 countries between April, 1998, and August, 2004, with a median follow-…
Are media warnings about the adverse health effects of modern life self-fulfilling? An experimental study on idiopathic environmental intolerance att…
2013
article i nfo Objective: Medically unsubstantiated 'intolerances' to foods, chemicals and environmental toxins are com- mon and are frequently discussed in the media. Idiopathic environmental intolerance attributed to electro- magnetic fields (IEI-EMF) is one such condition and is characterized by symptoms that are attributed to exposure to electromagnetic fields (EMF). In this experiment, we tested whether media reports promote the development of this condition. Methods: Participants (N=147) were randomly assigned to watch a television report about the adverse health effects of WiFi (n=76) or a control film (n=71). After watching their film, participants received a sham exposure to a WiFi …
Static posturography with dynamic tests. Usefulness of biomechanical parameters in assessing vestibular patients.
2012
Abstract Introduction and objective Posturography allows us in evaluating postural control. This study showed the posturographic parameters that were useful for assessing the functional ability to maintain balance in our sample of vestibular patients. Material and methods Of a total of 89 patients, 59 were healthy subjects and 30 had a peripheral vestibular disorder. The subjects were studied using the posturographic NedSVE/IBV system, combining static (Romberg) and dynamic (stability limits and rhythmic weight shifts) tests. We then compared the measurements found in the groups. Results Normal subjects showed significantly lower oscillations than our patients in all of the posturographic p…