Search results for "PERFORMANCE."
showing 10 items of 4178 documents
Differential contributions of the two human cerebral hemispheres to action timing
2019
Rhythmic actions benefit from synchronization with external events. Auditory-paced finger tapping studies indicate the two cerebral hemispheres preferentially control different rhythms. It is unclear whether left-lateralized processing of faster rhythms and right-lateralized processing of slower rhythms bases upon hemispheric timing differences that arise in the motor or sensory system or whether asymmetry results from lateralized sensorimotor interactions. We measured fMRI and MEG during symmetric finger tapping, in which fast tapping was defined as auditory-motor synchronization at 2.5 Hz. Slow tapping corresponded to tapping to every fourth auditory beat (0.625 Hz). We demonstrate that t…
Right inferior frontal gyrus implements motor inhibitory control via beta-band oscillations in humans
2021
Motor inhibitory control implemented as response inhibition is an essential cognitive function required to dynamically adapt to rapidly changing environments. Despite over a decade of research on the neural mechanisms of response inhibition, it remains unclear, how exactly response inhibition is initiated and implemented. Using a multimodal MEG/fMRI approach in 59 subjects, our results reliably reveal that response inhibition is initiated by the right inferior frontal gyrus (rIFG) as a form of attention-independent top-down control that involves the modulation of beta-band activity. Furthermore, stopping performance was predicted by beta-band power, and beta-band connectivity was directed f…
Effects of a 20-week high-intensity strength and sprint training program on tibial bone structure and strength in middle-aged and older male sprint a…
2017
This randomized, controlled, high-intensity strength and sprint training trial in middle-aged and older male sprint athletes showed significant improvements in mid-tibial structure and strength. The study reveals the adaptability of aging bone, suggesting that through a novel, intensive training stimulus it is possible to strengthen bones during aging. High-load, high-speed and impact-type exercise may be an efficient way of improving bone strength even in old age. We evaluated the effects of combined strength and sprint training on indices of bone health in competitive masters athletes, who serve as a group of older people who are likely to be able to participate in vigorous exercise of th…
Nutritional strategies in an elite wheelchair marathoner at 3900 m altitude: a case report.
2019
Abstract Background Altitude training is a common practice among middle-distance and marathon runners. During acclimatization, sympathetic drive may increase resting metabolic rate (RMR), therefore implementation of targeted nutritional interventions based on training demands and environmental conditions becomes paramount. This single case study represents the first nutritional intervention performed under hypobaric hypoxic conditions (3900 m) in Paralympic sport. These results may elucidate the unique nutritional requirements of upper body endurance athletes training at altitude. Case presentation This case study examined the effects of a nutritional intervention on the body mass of a 36-y…
The Gut Metagenome Changes in Parallel to Waist Circumference, Brain Iron Deposition, and Cognitive Function.
2017
Context Microbiota perturbations seem to exert modulatory effects on emotional behavior, stress-, and pain-modulation systems in adult animals; however, limited information is available in humans. Objective To study potential relationships among the gut metagenome, brain microstructure, and cognitive performance in middle-aged, apparently healthy, obese and nonobese subjects after weight changes. Design This is a longitudinal study over a 2-year period. Setting A tertiary public hospital. Patients or other participants Thirty-five (18 obese) apparently healthy subjects. Intervention(s) Diet counseling was provided to all subjects. Obese subjects were followed every 6 months. Main outcome me…
High-definition transcranial direct current stimulation to both primary motor cortices improves unimanual and bimanual dexterity.
2017
While most research on brain stimulation with transcranial direct current stimulation (tDCS) targets unimanual motor tasks, little is known about its effects on bimanual motor performance. This study aims to investigate the effects of tDCS on unimanual as well as bimanual motor dexterity. We examined the effects of bihemispheric anodal high-definition tDCS (HD-atDCS) on both primary motor cortices (M1) applied concurrent with unimanual and bimanual motor training. We then measured the effects with the Purdue Pegboard Test (PPT) and compared them to a sham stimulation. Between a pretest and posttest, 31 healthy, right-handed participants practiced the PPT on three consecutive days and receiv…
Heart rate acceleration at relative workloads during treadmill and overground running for tracking exercise performance during functional overreaching
2020
AbstractMaximal rate of heart rate (HR) increase (rHRI) as a measure of HR acceleration during the transition from rest to exercise, or during an increase in workload, tracks exercise performance. rHRI assessed at relative rather than absolute workloads may track performance better, and a field test would increase applicability. This study therefore aimed to evaluate the sensitivity of rHRI assessed at individualised relative workloads during treadmill and overground running for tracking exercise performance. Treadmill running performance (5 km time trial; 5TTT) and rHRI were assessed in 11 male runners following 1 week of light training (LT), 2 weeks of heavy training (HT) and a 10-day tap…
Associations between neuropsychological performance and appetite-regulating hormones in anorexia nervosa and healthy controls: Ghrelin's putative rol…
2019
Anorexia nervosa (AN) is a severe eating disorder accompanied by alterations in endocrinological circuits and deficits in neuropsychological performance. In this study, a series of appetite-regulating hormones (ghrelin, leptin, cholecystokinin, PYY, adiponectin, and visfatin) were measured under fasting conditions in female patients with AN and female healthy controls. All of the participants also underwent a battery of neuropsychological assessment [namely the Iowa Gambling Task (IGT), the Wisconsin Card Sorting Test (WCST), and the Stroop Color and Word Test (SCWT)]. As the main finding, we found that higher ghrelin levels predict better performance in the IGT. Ghrelin may be a putative m…
Heterogeneous Indicators of Cognitive Performance and Performance Variability Across the Lifespan
2020
Reaction time (RT) and RT variability are core components of cognitive performance that can be captured through brief and easy-to-administer tasks of simple RT and choice RT. The current study aims to describe age-related differences in cognitive performance, toward better characterizing normative performance across the lifespan. We examined mean and variability of response times on a simple RT and choice RT tasks in a large and diverse web-based sample (10,060 visitors to TestMyBrain.org). We also examined lifespan-related differences in response time variability using multiple different approaches (raw variability, mean scaled variability, and mean residualized variability). These analyse…
Transferability of PCR-based diagnostic protocols: An international collaborative case study assessing protocols targeting the quarantine pine pathog…
2019
Producción Científica