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1.
ObjectivesCricket batting is performed under demanding constraints, which requires rapid and accurate decision making for successful achievement of the skill goal. To understand how batsmen negotiate these constraints, the capability of highly skilled and low skilled cricket batsmen to utilise visual information prior to and during sections of ball flight to strike balls delivered by fast bowlers was examined.MethodSix highly skilled and six low skilled batsmen faced different types of balls delivered by three fast bowlers. Batsmen wore vision occlusion spectacles and were required to strike delivered balls, while their vision of the bowler's delivery action and ball flight was selectively occluded. Three vision conditions were randomly designed that included temporal occlusion at: (i) a point prior to ball release (providing only advance information), (ii) a point prior to ball bounce (providing advance and ball flight information) and (iii) no occlusion (where all advance, ball flight and bounce information were visible). Foot movements made forward or backward were assessed as a measure of ball length judgement, while the quality of bat–ball contact was assessed as a measure of interception.ResultsResults demonstrated the superior capability of highly skilled batsmen to utilise information prior to ball release to judge short ball length. Expert batsmen were better able to utilise ball flight information prior to and post-bounce to attain a superior number of bat–ball contacts.ConclusionsFindings demonstrate that the mechanism of experts to deal with task constraints when attempting to intercept a delivered ball is their capability to pick-up visual information to judge ball landing position.  相似文献   

2.
The differences in P300 latency, P300 amplitude, response selection, and reaction time between skilled and less-skilled cricket batsmen have been investigated. Eight skilled and ten less-skilled right-handed batsmen each viewed 100 in-swing, 100 out-swing, and 40 slower deliveries displayed in random sequence from projected video footage whilst their responses and electroencephalograms were recorded. Logistic regression was used to derive a discriminative function for the P300 data. This was done to determine whether the skilled batsmen differed from the less-skilled batsmen on the basis of pooled P300 amplitude and latency data. All the batsmen were correctly characterised as being skilled or less-skilled. Logistic regression equations with reaction time and correctness of response data indicated that behavioural data do not correctly classify skilled performance. It is suggested that skilled cricket batsmen have a superior perceptual decision-making ability compared with less-skilled cricket batsmen, as measured by P300 latency and amplitude. This appears to be the first study showing a link between skill and cerebral cortical activity during a perceptual cricket batting task and it could pave the way for future studies on mental processing in cricket batsmen.  相似文献   

3.
This article outlines a study that sought to discriminate visual anticipation skill between highly skilled (n = 13), elite club (n = 17), and elite youth (n = 9) cricket batsmen. Participants watched a video-based temporal occlusion test of a bowler and anticipated with a motor response. Results indicated that overall highly skilled and club batsmen were significantly superior to youth batsmen. Highly skilled batsmen anticipated above chance at ball release occlusion, whereas club and youth batsmen were above chance at no occlusion. Findings indicate that video-based temporal occlusion with a motor response is sensitive to discriminate anticipation in skilled players.  相似文献   

4.
The relationship between perception-action coupling and anticipatory skill in an interceptive task was examined using an in-situ temporal occlusion paradigm. Skilled and novice cricket batsmen were required to predict the direction of balls bowled towards them under four counterbalanced response conditions of increasing perception-action coupling: (i) verbal, (ii) lower-body movement only, (iii) full-body movement (no bat), and (iv) full-body movement with bat (i.e., the usual batting response). Skilled but not novice anticipation was found to improve as a function of coupling when responses were based on either no ball-flight, or early ball-flight information, with a response requiring even the lowest degree of body movement found to enhance anticipation when compared to a verbal prediction. Most importantly, a full-body movement using a bat elicited greater anticipation than an equivalent movement with no bat. This result highlights the important role that the requirement and/or opportunity to make bat-ball interception may play in eliciting skill differences for anticipation. Results verify the importance of using experimental conditions and task demands that closely reflect the natural performance environment in order to reveal the full nature of the expert advantage.  相似文献   

5.
8—12岁超常与常态儿童的检测时比较   总被引:2,自引:0,他引:2  
研究者采用两种视觉检测时任务,比较了8至12岁超常和常态儿童的检测时发展变化特点。结果发现:随着年龄的增长,超常组和常态组儿童的检测时都呈现出逐步减小的趋势,并且对于不同任务的检测时,两组儿童的发展速度不同,但均未表现出性别差异;在不同的年龄段和检测时任务中,超常组儿童的检测时均显著地快于常态组儿童。通过对两组儿童的检测时发展速率的比较还发现,儿童的检测时发展基本上不受学校知识或经验的影响。另外,两组儿童的检测时和智力测验分数之间都有中等程度的负相关。  相似文献   

6.
The importance of optimal visual function in demanding interceptive tasks is far from established. The aim of the study was to determine whether induced myopic blur and hence sub-optimal visual function would give rise to a detrimental effect on performance in the execution of an interceptive task. The batting performance of grade level cricket players was assessed facing a bowling machine whilst wearing contact lenses of four different refractive conditions (plano (nil), +1.00, +2.00 and +3.00D over-refraction), inducing increasing amounts of myopic blur. Performance for each condition was assessed based both on the shot quality against each delivery judged by a qualified cricket coach blind to each condition, along with an evaluation of the quality of ball-bat contact for each delivery. No significant change was found in batting performance with the introduction of +1.00 and +2.00D of induced myopic blur. A +3.00D over-correction was required before any significant decrease in batting performance was detected, demonstrating that batters needed to be essentially legally blind (as simulated through the use of the +3.00D over-refraction) before there was any significant measurable decrement in batting performance. We concluded that optimal visual correction is not necessarily required for optimal performance in a demanding interceptive task, and that the human perceptual-motor system is capable of compensating for marked alterations in input.  相似文献   

7.
The authors investigated the use of visual feedback as a form of knowledge of results (KR) for the control of rapid (200-250 ms) reaching movements in 40 participants. They compared endpoint accuracy and intraindividual variability of a full-vision group (FV) with those of no-vision groups provided with KR regarding (a) the endpoint in numerical form, (b) the endpoint in visual form, or (c) the endpoint and the trajectory in visual form (DEL). The FV group was more accurate and less variable than were the no-vision groups, and the analysis of limb trajectory variability indicated that their superior performance resulted primarily from better movement planning rather than from online visual processes. The FV group outperformed the DEL group even though both groups were obtaining the same amount of spatial visual information from every movement. That finding suggests that the effectiveness with which visual feedback is processed offline is not a simple function of the amount of visual information available, but depends on how that information is presented.  相似文献   

8.
The authors investigated the use of visual feedback as a form of knowledge of results (KR) for the control of rapid (200-250 ms) reaching movements in 40 participants. They compared endpoint accuracy and intraindividual variability of a full-vision group (FV) with those of no-vision groups provided with KR regarding (a) the endpoint in numerical form, (b) the endpoint in visual form, or (c) the endpoint and the trajectory in visual form (DEL). The FV group was more accurate and less variable than were the no-vision groups, and the analysis of limb trajectory variability indicated that their superior performance resulted primarily from better movement planning rather than from online visual processes. The FV group outperformed the DEL group even though both groups were obtaining the same amount of spatial visual information from every movement. That finding suggests that the effectiveness with which visual feedback is processed offline is not a simple function of the amount of visual information available, but depends on how that information is presented.  相似文献   

9.
This article describes a new automated method for the controlled occlusion of vision during natural tasks. The method permits the time course of the presence or absence of visual information to be linked to identifiable events within the task of interest. An example application is presented in which the method is used to examine the ability of cricket batsmen to pick up useful information from the prerelease movement patterns of the opposing bowler. Two key events, separated by a consistent within-action time lag, were identified in the cricket bowling action sequence—namely, the penultimate foot strike prior to ball release (Event 1), and the subsequent moment of ball release (Event 2). Force-plate registration of Event 1 was then used as a trigger to facilitate automated occlusion of vision using liquid crystal occlusion goggles at time points relative to Event 2. Validation demonstrated that, compared with existing approaches that are based on manual triggering, this method of occlusion permitted considerable gains in temporal precision and a reduction in the number of unusable trials. A more efficient and accurate protocol to examine anticipation is produced, while preserving the important natural coupling between perception and action.  相似文献   

10.
In three experiments, we investigated whether the ease with which distracting sounds can be ignored depends on their distance from fixation and from attended visual events. In the first experiment, participants shadowed an auditory stream of words presented behind their heads, while simultaneously fixating visual lip-read information consistent with the relevant auditory stream, or meaningless "chewing" lip movements. An irrelevant auditory stream of words, which participants had to ignore, was presented either from the same side as the fixated visual stream or from the opposite side. Selective shadowing was less accurate in the former condition, implying that distracting sounds are harder to ignore when fixated. Furthermore, the impairment when fixating toward distractor sounds was greater when speaking lips were fixated than when chewing lips were fixated, suggesting that people find it particularly difficult to ignore sounds at locations that are actively attended for visual lipreading rather than merely passively fixated. Experiments 2 and 3 tested whether these results are specific to cross-modal links in speech perception by replacing the visual lip movements with a rapidly changing stream of meaningless visual shapes. The auditory task was again shadowing, but the active visual task was now monitoring for a specific visual shape at one location. A decrement in shadowing was again observed when participants passively fixated toward the irrelevant auditory stream. This decrement was larger when participants performed a difficult active visual task there versus fixating, but not for a less demanding visual task versus fixation. The implications for cross-modal links in spatial attention are discussed.  相似文献   

11.
Inspection time, defined as the minimum duration for which two different stimuli must be presented if they are to be perceived as different, was measured for both auditory and visual stimuli. The minimum durations were determined by means of a two- alternative forced-choice task for 50 children whose average age was 12 years 2 months. The times were correlated with the children's verbal (Mill-Hill vocabulary) and nonverbal (Raven matrices) intelligence. The Kendall correlation coefficients were ?.3188 and ?.0929 for the auditory and visual inspection times with verbal intelligence, and ?.2322 and ?.2676 for those times with nonverbal intelligence. Auditory and visual inspection times were correlated .1721 with each other. These results do not support earlier claims that inspection time is closely related to conventional measures of intelligence.  相似文献   

12.
"Markov at the bat": a model of cognitive processing in baseball batters   总被引:2,自引:0,他引:2  
Anecdotal evidence from players and coaches indicates that cognitive processing (e.g., expectations about the upcoming pitch) plays an important role in successful baseball batting, yet this aspect of hitting has not been investigated in detail. The present study provides experimental evidence that prior expectations significantly influence the timing of a baseball swing. A two–state Markov model was used to predict the effects of pitch sequence and pitch count on batting performance. The model is a hitting strategy of switching between expectancy states using a simple set of transition rules. In a simulated batting experiment, the model provided a good fit to the hitting performance of 6 experienced college baseball players, and the estimated model parameters were highly correlated with playing level.  相似文献   

13.
Visual reaction time and high-speed ball games   总被引:7,自引:0,他引:7  
P McLeod 《Perception》1987,16(1):49-59
Laboratory measures of visual reaction time suggest that some aspects of high-speed ball games such as cricket are 'impossible' because there is insufficient time for the player to respond to unpredictable movements of the ball. Given the success with which some people perform these supposedly impossible acts, it has been assumed by some commentators that laboratory measures of reaction time are not applicable to skilled performers. An analysis of high-speed film of international cricketers batting on a specially prepared pitch which produced unpredictable movement of the ball is reported, and it is shown that, when batting, highly skilled professional cricketers show reaction times of around 200 ms, times similar to those found in traditional laboratory studies. Furthermore, professional cricketers take roughly as long as casual players to pick up ball flight information from film of bowlers. These two sets of results suggest that the dramatic contrast between the ability of skilled and unskilled sportsmen to act on the basis of visual information does not lie in differences in the speed of operation of the perceptual system. It lies in the organisation of the motor system that uses the output of the perceptual system.  相似文献   

14.
The research investigated the relationship between spatial frequency and visual field in a facial recognition task. Faces of neutral affect (Ekman, 1979) were tachistoscopically presented to the right or left visual field. The faces were presented alone, or masked with square wave gratings of 1, 24, or 48 cycles/degree, for a duration of 10 msec. Accuracy in recognizing each target face from a group of five served as the dependent measure. Subjects were 15 males and 15 females. ANOVA results included a frequency x visual field interaction effect (p less than .001). As was hypothesized, LVF errors were highest in the absence of low spatial frequencies, while RVF errors were highest when a higher range of spatial frequencies was removed. These results confirm that the hemispheres show a differential efficiency in processing high and low spatial frequency information in faces. They also offer empirical evidence to support the clinical findings that both hemispheres contribute to facial recognition.  相似文献   

15.
The purpose of this study was to test the potential relationship between REM sleep and information processing with inversion of the visual field. In the first experiment, four male subjects slept in the laboratory for two sessions of 6 consecutive nights: 2 adaptation nights, 2 nights of polysomnography, and 2 nights of dream collection. During the days preceding Nights 3, 4, 5, and 6 of each session, the subjects wore glasses which, during the second session, completely inverted (rotation of 180 degrees) their visual field. In a second experiment with four other male subjects, the order of conditions was reversed, and the experimental condition (visual inversion) was introduced a second time. When the data of the two experiments were combined, there was a significant (p less than .01) increase in the percentage of REM sleep from Nights 3 and 4 of the control condition to Nights 3 and 4 of the visual inversion condition, but there was no significant change in any of the other sleep stages. There was a significant decrease in horizontal (p less than .04) and vertical (p less than .005) REM density and in the density of vertical REM bursts (p less than .02). The increase in REM sleep supports the hypothesis that REM sleep contributes to information processing while the decrease in REM density suggests that this component of REM sleep may be involved in a homeostatic process of sensory input.  相似文献   

16.
The visual system is exquisitely adapted to the task of extracting conceptual information from visual input with every new eye fixation, three or four times a second. Here we assess the minimum viewing time needed for visual comprehension, using rapid serial visual presentation (RSVP) of a series of six or 12 pictures presented at between 13 and 80 ms per picture, with no interstimulus interval. Participants were to detect a picture specified by a name (e.g., smiling couple) that was given just before or immediately after the sequence. Detection improved with increasing duration and was better when the name was presented before the sequence, but performance was significantly above chance at all durations, whether the target was named before or only after the sequence. The results are consistent with feedforward models, in which an initial wave of neural activity through the ventral stream is sufficient to allow identification of a complex visual stimulus in a single forward pass. Although we discuss other explanations, the results suggest that neither reentrant processing from higher to lower levels nor advance information about the stimulus is necessary for the conscious detection of rapidly presented, complex visual information.  相似文献   

17.
Subjects were provided with outline maps that were incomplete in several details. Brief, simultaneous, visual and auditory instructions were given for completing some of the missing details. Certain items could be completed on the basis of direct information contained in one or other of the sensory modalities. Others, however, could be completed only because of their relation to details capable of location by direct instruction. Information important for the completion of map details was distributed randomly among short passages of unconnected words. All relevant visual and aural clues were presented simultaneously in every case. Opportunities for alternations of attention were curtailed.

Thirty-six subjects were randomly assigned to three experimental conditions, and to two groups that were given different instructions. One group was told that relevant information would always appear simultaneously, while the other group was not allowed this information.

The number of successfully located simultaneous pairs of items presented for direct location was found to be no greater than could be expected by chance. The total number of correctly located items was less than 50 per cent of the possible items. There was no difference in the number of correctly located simultaneous pairs of items between the “instructed” and the “uninstructed” groups. The “uninstructed” group did not learn in the course of the experiment that all relevant material was presented simultaneously. Significantly more correct completions were made with the visual material than with the auditory. It is concluded that successful division of attention did not occur.  相似文献   

18.
In behavior analysis, visual inspection of graphic information is the standard by which data are evaluated. Efforts to supplement visual inspection using inferential statistical procedures to assess intervention effects (e.g., analysis of variance or time-series analysis) have met with opposition. However, when serial dependence is present in the data, the use of visual inspection by itself may prove to be problematic. Previously published reports demonstrate that autocorrelated data influence trained observers' ability to identify level treatment effects and trends that occur in the intervention phase of experiments. In this report, four recent studies are presented in which autoregressive equations were used to produce point-to-point functions to simulate experimental data. In each study, various parameters were manipulated to assess trained observers' responses to changes in point-to-point functions from the baseline condition to intervention. Level shifts over baseline behavior (treatment effect), as well as no change from baseline (no treatment effect or trend), were most readily identified by observers, but trends were rarely recognized. Furthermore, other factors previously thought to augment and improve observers' responses had no impact. Results are discussed in terms of the use of visual inspection and the training of behavior analysts.  相似文献   

19.
Visual information plays an adaptive role in the relation between bimanual force coupling and error corrective processes of isometric force control. In the present study, the evolving distribution of the relative phase properties of bimanual isometric force coupling was examined by scaling within a trial the temporal feedback rate of visual intermittency (short to long presentation intervals and vice versa). The force error (RMSE) was reduced, and time-dependent irregularity (SampEn) of the force output was increased with greater amounts of visual information (shorter intermittency). Multi-stable coordination patterns of bimanual isometric force control were differentially shifted toward and away from the intrinsic dynamics by the changing the intermittency of visual information. The distribution of Hilbert transformed relative phase values showed progressively a predominantly anti-phase mode under less intermittent visual information to predominantly an in-phase mode with limited (almost no) visual information. Correlation between the hands showed a continuous reduction, rather than abrupt “transition,” with increase in visual information, although no mean negative correlation was realized, despite the tendency towards an anti-phase distribution. Lastly, changes in both the performance outcome and bimanual isometric force coordination occurred at visual feedback rates faster than the minimal visual processing times established from single limb movement and isometric force protocols.  相似文献   

20.
Two experiments investigated visual and proprioceptive recognition of cursive letters in young children. In Experiment 1, children aged 3-5 years were asked to recognize a visually presented target letter after a 3s inspection time, from among two distracters: a highly and a moderately similar letter. Visual letter recognition improved rapidly between 3 and 5 years and was a function of the "uniqueness" of letter shape and of letter frequency. In Experiment 2, children aged 4-6 years were asked to recognize a target letter from among 2 distracters, after having traced over the letter in a "blind" condition, with their hand guided by the experimenter. Proprioceptive recognition developed more slowly than visual recognition, and was not a function of letter frequency. The results are discussed in terms of integration versus differentiation of perceptual information, and of the tendency to base recognition on local rather than global similarity.  相似文献   

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