Search results for "Motor performance"
showing 10 items of 378 documents
Motor Activity Improves Temporal Expectancy
2015
International audience; Certain brain areas involved in interval timing are also important in motor activity. This raises the possibility that motor activity might influence interval timing. To test this hypothesis, we assessed interval timing in healthy adults following different types of training. The pre- and post-training tasks consisted of a button press in response to the presentation of a rhythmic visual stimulus. Alterations in temporal expectancy were evaluated by measuring response times. Training consisted of responding to the visual presentation of regularly appearing stimuli by either: (1) pointing with a whole-body movement, (2) pointing only with the arm, (3) imagining pointi…
Self-rated health and mortality: Could clinical and performance-based measures of health and functioning explain the association?
2005
It is well established that self-rated health (SRH) predicts mortality even when other indicators of health status are taken into account. It has been suggested that SRH measures a wide array of mortality-related physiological and pathological characteristics not captured by the covariates included in the analyses. Our aim was to test this hypothesis by examining the predictive value of SRH on mortality controlling for different measurements of body structure, performance-based functioning and diagnosed diseases with a population-based, prospective study over an 18-year follow-up. Subjects consisted of 257 male residents of the city of Jyväskylä, central Finland, aged 51-55 and 71-75 years.…
Effect of focal cerebellar lesions on procedural learning in the serial reaction time task
1998
Prior studies have shown that procedural learning is severely impaired in patients with diffuse cerebellar damage (cortical degeneration) as measured by the serial reaction time task (SRTT). We hypothesize that focal cerebellar lesions can also have lateralized effects on procedural learning. Our objective was to assess the effects of focal cerebellar lesions in procedural learning as measured by the SRTT. We studied 14 patients with single, unilateral vascular lesions in the territory of the posterior-inferior or superior cerebellar artery, who were compared with ten age- and sex-matched controls in a one-handed version of the SRTT. Patients with lesions at any other level of the brain or …
Neck Muscle Vibration and Spatial Orientation During Stepping in Place in Humans
2002
Unilateral long-lasting vibration was applied to the sternomastoid muscle to assess the influence of asymmetric neck proprioceptive input on body orientation during stepping-in-place. Blindfolded subjects performed 3 sequences of 3 trials, each lasting 60 s: control, vibration applied during stepping (VDS), and vibration applied before stepping (VBS). VDS caused clear-cut whole body rotation toward the side opposite to vibration. The body rotated around a vertical axis placed at about arm's length from the body. The rotation did not begin immediately on switching on the vibrator. The delay varied from subject to subject from a few seconds to about 10 s. Once initiated, the angular velocity…
Perceptual-Cognitive Skills and Performance in Orienteering
2008
The goal was analysis of the perceptual-cognitive skills associated with sport performance in orienteering in a sample of 22 elite and 17 nonelite runners. Variables considered were memory, basic orienteering techniques, map reading, symbol knowledge, map-terrain-map identification, and spatial organisation. A computerised questionnaire was developed to measure the variables. The reliability of the test (agreement between experts) was 90%. Findings suggested that competence in performing basic orienteering techniques efficiently was a key variable differentiating between the elite and the nonelite athletes. The results are discussed in comparison with previous studies.
Cross-notational semantic priming between symbolic and nonsymbolic numerosity
2008
Symbolic and nonsymbolic numerosities produce similar behavioural effects and activate the same brain areas. These results have usually been interpreted in terms of a common, notation-independent magnitude representation. However, semantic priming between symbolic and nonsymbolic inputs has been somehow elusive (e.g., Koechlin, Naccache, Block, & Dehaene, 1999). In Experiment 1, we looked at whether cross-notational semantic priming depends on exact numerical meaning. Dice faces and digits were mixed as prime and target. Semantic priming occurred when prime and target were in the same notation as much as when they were in different notation. In Experiment 2, we found cross-notation sem…
Investigating centre of mass stabilisation as the goal of posture and movement coordination during human whole body reaching
2000
In the light of experimental results showing significant forward centre of mass (CoM) displacements within the base of support, this study investigated if whole body reaching movements can be executed whilst keeping the CoM fixed in the horizontal axis. Using kinematic simulation techniques, angular configurations were recreated from experimental data imposing two constraints: a constant horizontal position of the CoM and an identical trajectory of the hand to grasp an object. The comparison between recorded and simulated trials showed that stabilisation of the CoM was associated with greater backward hip displacements, which became more marked with increasing object distance. This was in c…
The N400 as a correlate of interpretively relevant linguistic rules: evidence from Hindi.
2009
Classical views on the electrophysiology of language assume that different event-related potential (ERP) components index distinct linguistic subdomains. Hence, left-anterior negativities are often viewed as correlates of rule-based linguistic knowledge, whereas centro-parietal negativities (N400s) are taken to reflect (non-rule-based) semantic memory or aspects of lexical-semantic predictability. The present ERP study of case marking in Hindi challenges this clear-cut dichotomy. Though determined by a grammatical rule, the choice of subject case in Hindi is also interpretively relevant as it constrains the range of possible interpretations of the subject. For incorrect subject cases, we ob…
Kinematic and dynamic processes for the control of pointing movements in humans revealed by short-term exposure to microgravity.
2004
The generation of accurate motor commands requires implicit knowledge of both limb and environmental dynamics. The action of gravity on moving limb segments must be taken into account within the motor command, and may affect the limb trajectory chosen to accomplish a given motor task. Exactly how the CNS deals with these gravitoinertial forces remains an open question. Does the CNS measure gravitational forces directly, or are they accommodated in the motor plan by way of internal models of physical laws? In this study five male subjects participated. We measured kinematic and dynamic parameters of upward and downward arm movements executed at two different speeds, in both normal Earth grav…
Primary motor area contribution to attentional reorienting after distraction
2008
The anatomical structures involved in distraction-related processing in the auditory domain were investigated using magnetoencephalography. Participants performed a duration-discrimination task on a sequence of 200 and 400 ms long tones. Infrequent (12%) task-irrelevant pitch changes resulted in slower discriminative responses and more errors. Event-related potentials to these changes show an increased N1, a mismatch negativity, a P3a, and a reorienting negativity. The event-related magnetic fields revealed focal activities in superior and medial temporal areas in the N1/mismatch negativity time range. No significant activity was found in the P3a interval. In the reorienting negativity inte…