The man who lost his body: Suboptimal multisensory integration yields body awareness problems after a right temporoparietal brain tumour

Reports on patients who lack ownership over their entire body are extremely rare. Here, we present patient SA who suffered from complete body disownership after a tumour resection in the right temporoparietal cortex. Neuropsychological assessment disclosed selective bilateral ownership problems, despite intact primary visual and somatosensory senses. SA's disownership seems to stem from a suboptimal multimodal integration, as shown by the rubber hand illusion and the beneficial effect during and after simple exercises aiming at multisensory recalibration.     

Biomechanical Motor Patterns in Normal Walking

Motor patterns in normal human gait are evident in several biomechanical and EMG analyses over the stride period. Some of these patterns are invariant over the stride period with changes of cadence, while others are closely correlated with speed changes. The findings for slow, natural, and fast walking are summarized: 1. Joint angle patterns over the stride period are quite invariant, and do not change with cadence;

2. Moment of force patterns at the ankle are least variable and quite consistent at all speeds;

3. A recently defined support moment is quite consistent at all speeds.

4. Moments at the knee and hip are highly variable at all cadences but decrease their variability as cadence increases;

5. Mechanical power patterns at all joints show consistent timing over the stride period;

6. EMG profiles of 5 muscles show consistent timing over the stride, but the amplitude increases as walking speed increases.

Arguments are presented to support the concept that walking speed is largely controlled by gain and that the timing of the motor patterns, which is extremely tightly synchronized with the anatomical position, is under major afferent control.     

Relationships Among Selected Tests of Spatial Orientation Ability

The purpose of this study was to investigate the relationships between selected tests of spatial orientation ability. 2 tests which have been used as predictors of spatial ability (Guilford-Zimmerman Aptitude Survey, Parts V and VI) plus 2 newly developed tests designed to measure that ability were given to 202 Junior high school boys aged 11-15 yr. 3 of these tests were of the paper and pencil type while one was a physical performance (tumbling) test. The paper-and-pencil tests correlated significantly with each other (.62, .61, .44) but the physical performance test did not correlate significantly with any of the other tests.     

Effects of Local Muscular Fatigue Due to Isotonic and Isometric Exercise Upon Fractionated Reaction Time Components

Fractionated RT for a right knee-extension task was assessed on eight male and eight female Ss over eight treatment days. Following four consecutive days of 75 RT trials /day to insure stabilized strength and RT components, Ss were administered two days of bench stepping and two days of isometric exercise designed to induce muscular fatigue of the knee extensors. Significant strength decrements of up to 24% were induced by both the isotonic (bench stepping) and isometric exercise treatment conditions but no changes were observed in fractionated RT components. The results would seem to indicate that performance differences in fine-versus gross-motor skill tasks due to fatigue need to be more carefully examined.     

Dynamics of Pushing

A standing individual can use several strategies for modulating pushing force magnitude. Using a static model, researchers have shown that the efficacy of those strategies varies considerably. In the present article, the authors propose a human motor control dynamic model for analyzing transients that occur when an individual is asked to modulate force magnitude. According to the model, the impedances of both the upper and the lower limbs influence the time course of force variations and foot placement has a profound effect on pushing force dynamics. With a feet-together posture, the center of pressure has a limited range of motion and changes in force may be preceded by initial changes in the opposite direction; that is, to decrease force, an individual must first increase force. When the feet are placed apart, individuals can move the center of pressure over a much larger range, thereby modulating pushing force magnitude, without reversing behavior, over a larger range of force magnitudes. Therefore, the best way to control pushing force at the hand may be by using the foot.     

Postural Stability and Hand Preference as Constraints on One-Handed Catching Performance in Children

Effects of postural state and hand preference as constraints on 1-handed catching performance were investigated in different ability groups of children aged 9-10 years. On the basis of pretest data, the authors classified 48 participants into groups of good, intermediate, and poor catchers (n = 16 in each) and asked them to perform 1-handed catches with their preferred and nonpreferred hands while standing and sitting. The good catchers' performance was not affected by the imposed postural constraints but did improve when they used the preferred hand. A similar effect of hand preference was evident in the intermediate and poor catchers, but there was also an effect of postural constraint. Independent of hand preference, intermediate catchers' performance while seated improved significantly compared with that during standing. For poor catchers, there was an interaction between hand preference and posture; significant improvement was evident only when they used the preferred hand in the sitting condition. The finding that manipulation of posture and hand preference affected performance outcomes indicates that perceptual skill is not the only influence on catching performance in children. Manipulation of those key constraints may facilitate the acquisition of catching skill, but more research is needed to determine the permanence of those effects.     

Do clutch players win the game? Testing the validity of the clutch player's reputation in basketball

ObjectivesThe sport psychology literature recognizes the existence of clutch behavior among elite athletes. The present study questions the validity of the clutch reputation in basketball. The performance of clutch players was compared to that of their teammates, using a broad approach that included different performance measures.DesignEight basketball experts ranked NBA players according to their perceived reputation of being clutch shooters. The selection procedure resulted in a sample of 16 clutch players who had successfully made a game-deciding shot, or had made a successful shot in the final few minutes to tie the game, during the 2003–2006 seasons.MethodData were collected from play-by-play reports of 222 tied NBA games during the 2005–2006 season and playoffs. Data were reduced to the final five minutes of the second and fourth quarters in each close/tied game. A MANOVA and several ANOVAs were conducted in order to compare the performance measures of the clutch players and the average of their teammates, in game phases of low and high pressure.ResultsThe reported main effects of clutch versus non-clutch players suggest a superior performance of the clutch players. The results also show that the clutch players improved their performance in the final, most decisive phase of the game, which could be interpreted as evidence for clutch ability. However, the clutch players did not improve their general shooting skills, as might have been expected.ConclusionsTop NBA players, like most other people, do not perform better under pressure situations, at least not while considering their chances of making a shot, but clutch players do influence the end-result of the game in other aspects.     

Adherence with universal precautions after immediate, personalized performance feedback

We evaluated the effects of immediate, personalized performance feedback on adherence with hand hygiene by health‐care staff in the context of a multiple baseline design across participants. Target behaviors reached mastery levels and were maintained near 100% throughout 2 months of maintenance probes.     

Instructed Hand Movements Affect Students’ Learning of an Abstract Concept From Video

Producing content-related gestures has been found to impact students’ learning, whether such gestures are spontaneously generated by the learner in the course of problem-solving, or participants are instructed to pose based on experimenter instructions during problem-solving and word learning. Few studies, however, have investigated the effect of (a) performing instructed gestures while learning concepts or (b) producing gestures without there being an implied connection between the gestures and the concepts being learned. The two studies reported here investigate the impact of instructed hand movements on students’ subsequent understanding of a concept. Students were asked to watch an instructional video—focused on the concept of statistical model—three times. Two experimental groups were given a secondary task to perform while watching the video, which involved moving their hands to mimic the placement and orientation of red rectangular bars overlaid on the video. Students were told that the focus of the study was multitasking, and that the instructed hand movements were unrelated to the material being learned. In the content-match group the placement of the hands reinforced the concept being explained, and in the content-mismatch group it did not. A control group was not asked to perform a secondary task. In both studies, findings indicate that students in the content-match group performed better on the posttest, and showed less variation in performance, than did students in the content-mismatch group, with control students falling in between. Instructed hand movement—even when presented as an unrelated, secondary task—can affect students’ learning of a complex concept.