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1.
Abstract

The purpose of this study was to determine the coding characteristics of kinesthetic location information acquired during learning trials. Forty-eight blindfolded subjects learned to make a linear response with the right hand to a criterion location during 13 trials. Upon completion of the learning trials, subjects performed 10 trials without knowledge of results (KR) under one of four treatment conditions which were defined by the limb used and the dominant source of feedback available. Specifically, the conditions were right-hand control with kinesthetic feedback, left-hand kinesthetic, right-hand visual, and left-hand visual. The results of the ANOVAs for absolute error (AE) and constant error (CE) from the no-KR trials revealed that the visual feedback groups made significantly greater response errors than did the kinesthetic feedback groups. The blocks main effect for CE was also significant. Analysis of variable error (VE) indicated that the visual feedback groups were significantly more consistent in their responses than were the kinesthetic feedback groups. Within a motor learning paradigm, the concept of a spatial-location coordinate system was supported by the similar performances of the right-handed and left-handed groups. A discrepancy in this system was identified when visual feedback was provided for controlling the response to a location previously learned with kinesthetic cues.  相似文献   

2.
Abstract

When subjects make simultaneous aiming movements of the upper limbs over different distances, assimilation effects are shown; the shorter distance limb overshoots when paired with a longer distance limb. However, it is not known whether assimilation effects are due to variations in distance per se or to variations in target location. To separate the possible influences of distance and location, 60 subjects made rapid bimanual aiming movements in one of four conditions. The two different-distance groups made a 20° movement in the left hand and a 60° movement in the right hand to either the same or different target locations. The comparison groups moved 20° in each limb. Somewhat surprisingly, spatial assimilations were greater when moving different distances to the same, rather than different, target locations, which suggests interlimb differences in distance mediate assimilation effects rather than target location. Temporal assimilations were greater when distance and location were varied, but the assimilations were not related to interlimb differences in velocity, as predicted by Marteniuk and MacKenzie (1980).  相似文献   

3.
Abstract

This study aimed at supporting the specificity of learning hypothesis, when aiming was based on internal cues, as directing the hand toward a “self-defined” target location. Participants practiced modest (20 trials) or intensive (720 trials) training with visual and proprioceptive information or proprioceptive information only. Pretests and posttests were performed in sensory conditions that did or did not match the training condition. Results showed that dynamic visual cues played a dominant role at the beginning of the task, and an intensive practice resulted in increased accuracy of kinesthetic information and efferent mechanisms of motor responses. These results have implications with regard to motor learning conceptions and training as a function of the task constraints.  相似文献   

4.
Abstract

Two groups of 10 novice subjects each were trained to perform attacking forehand drives in table tennis and land the balls as fast and as accurately as possible onto a target on the opposite side of the net under two different training conditions. Under the static training condition, the balls were to be struck from a constant position, and under the dynamic training condition, balls approached the subjects in a normal way. Both groups were tested under dynamic conditions prior to and after four days of training, during which they received 1,600 practice trials. Both groups of subjects were shown to increase the number of balls that landed on the target, and learning was also evident from an increased consistency of the direction of travel of the bat at the moment of ball/bat contact. However, no increase in consistency was found for the location of the bat at the moment of ball/bat contact and for the movement times. Thus, learning can occur in the absence of externally generated time-to-contact information, but this is not due to the establishment of a consistent movement form. Learning appears to progress from control at the moment of ball/bat contact backward, toward the moment of initiation.  相似文献   

5.
Abstract

The physical stimulus-psychological response relationship has been described as being either a prothetic or a metathetic continuum. That is, as the stimulus intensity increases, the response magnitude increases (prothetic) or stays the same (metathetic). The first experiment of this study considered this relationship for a movement having the final limb position, or location, as its goal. The second experiment focused on an extent movement. Subjects were tested on a linear positioning apparatus in both experiments using the method of constant stimuli for determining thresholds. On the basis of the Weber ratios and the JND's for the three increasing movement locations and extents, a metathetic continuum was determined as best describing location movements, while a prothetic continuum was considered more appropriate for extent movements. JND's indicated sensitive discrimination for location movements (1.08 to 1.39 cm for 25 to 75 cm locations) and less precise discrimination capability for extent movements (2.49 to 5.76 cm for 25 to 75 cm extents). Results are discussed in terms of their possible implications for addressing issues related to mechanisms subserving active kinesthesis, and in terms of their implications for experimental procedures for learning and memory investigations using discrete positioning responses.  相似文献   

6.
Distance and location assimilation effects in rapid bimanual movement   总被引：2，自引：0，他引：2  
When subjects make simultaneous aiming movements of the upper limbs over different distances, assimilation effects are shown; the shorter distance limb overshoots when paired with a longer distance limb. However, it is not known whether assimilation effects are due to variations in distance per se or to variations in target location. To separate the possible influences of distance and location, 60 subjects made rapid bimanual aiming movements in one of four conditions. The two different-distance groups made a 20 degrees movement in the left hand and a 60 degrees movement in the right hand to either the same or different target locations. The comparison groups moved 20 degrees in each limb. Somewhat surprisingly, spatial assimilations were greater when moving different distances to the same, rather than different, target locations, which suggests interlimb differences in distance mediate assimilation effects rather than target location. Temporal assimilations were greater when distance and location were varied, but the assimilations were not related to interlimb differences in velocity, as predicted by Marteniuk and MacKenzie (1980).  相似文献   

7.
Abstract

The experiment was designed to (a) examine age-related differences in the control of aiming movements, and (b) determine the locus of slowing in movement execution of older adults. Fitts's (1954) index of difficulty (ID) was used to manipulate movement execution demands, and kinematics were used to examine the response characteristics. Twelve young and 12 older adults performed simple aiming movements 10 cm or 20 cm in amplitude to targets of 0.5 cm, 1.0 cm, or 2.0 cm in width, resulting in IDs ranging from 3.32 to 6.32. The results for both young and older subjects support the prediction that movement time (MT) increases as a function of ID and that older adults are significantly slower and more affected by increases in ID than the young adults. Velocity and acceleration profiles of the older adults' movements displayed very different response characteristics than those of the young adults. The results suggest that older adults emphasize accuracy of response and are concerned with the latter phase of the movement in order to contact a target accurately.  相似文献   

8.
Abstract

When learning verbal information, an important aspect of practice is the method of rehearsal, which has been demonstrated to vary developmentally. A young child practices on an instance-by-instance basis (passive rehearsal), whereas older children and adults practice several items together (active rehearsal). This study investigated the effects of passive and active rehearsal on developmental processing differences for movement reproduction. Three methods of rehearsal were used at ages 5, 7, 11, and 19 years. A child-like strategy forced the subjects to practice location cues for each of eight movements, which were presented one at a time. The mature-strategy group practiced each new position presented with two previously presented positions. A subject-determined strategy group which allowed subjects to choose their own methods of rehearsal was included as a control. Significant ANOVAs supported the hypothesis that quality of rehearsal (active over passive) is important. For the 5- and 7-year-old children, a mature strategy facilitated performance over the child-like strategy, while the use of a child-like strategy hindered the performance when compared to a self-determined or mature strategy. The results of this study indicated the importance of active rehearsal for the younger child.  相似文献   

9.
研究目的:探讨优秀与一般水平摔跤运动员之间的颈部动觉感受性是否有差别,分析优秀摔跤运动员颈部动觉感受性特征,以提高其运动技能水平。研究方法:首先确定动觉心理特征包括肌紧张感与运动幅度感,分别以复制力与角度的误差绝对值大小作为反映它们高低的指标,以德国进口DIVAD系统中的DIVAD140为实验仪器,以37名男子自由跤运动员为被试,考察运动员颈部动觉感受性情况。实验设计采用3×2组间设计。结果显示:优秀自由跤运动员颈部前、左、右三个方向的肌紧张感都显著高于一般运动员;在颈部运动幅度感中,优秀运动员仅左屈运动幅度感明显高于一般运动员,但两组运动员在其他方向的运动幅度感没有差异。  相似文献   

10.
This study aimed at supporting the specificity of learning hypothesis, when aiming was based on internal cues, as directing the hand toward a "self-defined" target location. Participants practiced modest (20 trials) or intensive (720 trials) training with visual and proprioceptive information or proprioceptive information only. Pretests and posttests were performed in sensory conditions that did or did not match the training condition. Results showed that dynamic visual cues played a dominant role at the beginning of the task, and an intensive practice resulted in increased accuracy of kinesthetic information and efferent mechanisms of motor responses. These results have implications with regard to motor learning conceptions and training as a function of the task constraints.  相似文献   

11.
Two groups of 10 novice subjects each were trained to perform attacking forehand drives in table tennis and land the balls as fast and as accurately as possible onto a target on the opposite side of the net under two different training conditions. Under the static training condition, the balls were to be struck from a constant position, and under the dynamic training condition, balls approached the subjects in a normal way. Both groups were tested under dynamic conditions prior to and after four days of training, during which they received 1,600 practice trials. Both groups of subjects were shown to increase the number of balls that landed on the target, and learning was also evident from an increased consistency of the direction of travel of the bat at the moment of ball/bat contact. However, no increase in consistency was found for the location of the bat at the moment of ball/bat contact and for the movement times. Thus, learning can occur in the absence of externally generated time-to-contact information, but this is not due to the establishment of a consistent movement form. Learning appears to progress from control at the moment of ball/bat contact backward, toward the moment of initiation.  相似文献   

12.
Abstract

The present experiments examined the effects of stimulus velocity, stimulus duration, and stimulus uncertainty on the spatial-temporal structure and timing accuracy of coincident timing responses. The results of Experiment 1 indicated that the response structure for aimed movements differed from that of ballistic movements but response accuracy was comparable for both movement conditions. However, when information concerning the stimulus velocity was provided, the responses to the faster stimuli (i.e., stimuli of shorter duration) appeared to be “speeded up” copies of those to slower stimuli and response accuracy increased as the stimulus velocity increased (i.e., stimulus duration decreased). When the stimulus velocity was not known, subjects initiated a common response for approximately 260 msec and response accuracy appeared to decrease as the stimulus velocity increased (i.e., stimulus duration decreased). Experiment 2 indicated that the stimulus duration rather than the stimulus velocity was the major determiner of both the spatial-temporal structure and timing accuracy and that a very fast and a very slow stimulus will be responded to similarly when the stimulus duration remains constant.  相似文献   

13.
Abstract

Kindergarten boys (N = 12) played in three pieces of nonmoving equipment: wooden pilings, horizontal bars, and a geodesic dome. Movement was measured by use of the spatial dimensions of range, direction, and level and by bases of support as the body factor to determine which piece produced the greatest variety in each dimension and in bases of support. Photographic slides of the 12 subjects, in groups of four, were taken simultaneously by four Nikon motorized F-36 cameras at 5-sec intervals while they moved on the equipment. A flatbed coordinate digitizer plotted the movements of the body parts from raw images into an accurate two-dimensional Cartesian coordinate system. Computer programs transformed data into a three-dimensional system from which measurements were taken. Data was analyzed by using a three-factor repeated measure ANOVA, binomial proportions tests, Scheffes' tests, Kendall correlation, Wilcoxin T, and chi square. Results were significant at the .05 level and above. The bars elicited the greatest amount of range of movement. The pilings stimulated the most right, left, up, and down directional moves. The dome promoted more movement at a high level. Bases of support utilized were independent of the pieces of equipment used. This study provided evidence that a framework for analyzing movement utilizing Laban's spatial dimensions and the body factor of bases of support is appropriate. It also provided a photographic technique and computer programs to analyze movement in three dimensions.  相似文献   

14.
Abstract

We investigated the attention demands associated with implicit and explicit (motor) learning and performance using a probe reaction time paradigm. Two groups of participants learned a golf putting task over eight blocks of 50 trials performed from different distances. One group (errorless learning) began putting from the shortest distance (25 cm) and moved progressively back to the furthest distance (200 cm). A second group (errorful learning) began putting from the furthest distance (200 cm) and moved progressively closer (25 cm). Retention tests were used to assess learning in the two conditions, followed by transfer tests in which participants used either an unusual putter or a very unusual putter. Transfer to the unusual putters had an equivalent effect on the performance of both errorless and errorful learners, but probe reaction times were unaffected in the errorless learners, suggesting that execution of their movements was associated with reduced attention demands. Reducing errors during initial learning trials may encourage an implicit mode of learning and lower the demand for cognitive resources in subsequent performance.  相似文献   

15.
Abstract

The present experiment investigated the recall of terminal location and distance of both preselected and constrained short movements (12 cm ± 4 cm approximately) following 5 second and 30 second unfilled retention intervals. Systematic alteration of the magnitude and direction of the starting position for recall movements revealed that the distance moved markedly interfered with the recall of the terminal location, but distance was essentially recalled independently of terminal location. Recall of distance was superior to terminal location for both the unfilled retention intervals, and there was a decrease in location recall performances following the longer 30 second delay when compared to recall attempts after the shorter 5 second delay. The Findings are discussed in terms of recent proposals to account for the memory for, and control of, discrete limb movements.  相似文献   

16.
Abstract

Rapid, goal-directed elbow flexion movements were examined under interacting conditions of inertial loading and resistance to movement initiation. The resistance ceased when movement began, resulting in quick release movements. Inertial load slowed the movement and lengthened the agonist and antagonist electromyographic (EMG) burst durations. The quick release resulted in larger accelerations but only minimal changes in peak velocity. Most aspects of the triphasic EMG pattern were little affected by the quick release, but the build up of agonist EMG and the corresponding rate of static force development differed markedly between load and quick release conditions. These and other data suggest that the specific pattern of agonist muscle activation is set according to neuromuscular constraints of the antagonist muscle and the expectation of movement dynamics.  相似文献   

17.
Abstract

The purpose of the present study was to investigate the role of imagery in the short term retention of complex, visually-presented movement sequences. Twenty-eight high visual imagers (HIGHS) and 29 low visual imagers (LOWS) viewed and subsequently reproduced movement sequences consisting of eight component moves. Subjects reproduced six such sequences in each of two randomly ordered retention conditions: (1) rehearsal and (2) distraction. Half of the HIGHS and LOWS received instructions to employ imaginal processing strategies, while the other half received no such instructions. Analysis of the data indicated that HIGHS exhibited significantly higher free recall scores than LOWS. In addition, free recall of movement for all subjects was significantly disrupted following performance of a visual distraction task. The findings suggest that visual imagery may have played a functional role in the free recall of modeled movements. However, there was no indication that imagery was involved in the retention of serial information. The findings were explained in terms of the differential processing requirements of free and serial recall memory tasks.  相似文献   

18.
Abstract

The purpose of this study was to determine the usefulness of the components of a knowledge of results (KR) statement for organizing response correction. Forty-eight subjects learned to move a handle to a criterion location on a linear positioning apparatus. Error direction and distance components of the KR statement were manipulated across four independent groups. Two 4 × 15 Analyses of Variances were calculated on absolute error (AE) and constant error (CE) scores. The groups main effect, trials main effect, and the interaction groups × trials effect were significant for both analyses. Groups receiving directional information were more accurate in error correction than was the distance only group. Manipulation of distance information also influenced error correction on the initial trials. The results were interpreted as an indication that the learner's initial error corrections are based on directional information and that the distance of the error information which initially lacks meaning interferes with initial response accuracy.  相似文献   

19.
Abstract

The velocities and distances covered by players during competition serve as a basis for planning fitness regimes according to the specific demand of the sport. The techniques used to calculate these movement parameters have ranged from human judgements to technological solutions such as GPS and computer vision. This paper evaluates the accuracy of a computerized motion tracking system (SAGIT/Squash) that uses computer vision methods on video captured via a fixed single camera located centrally above the court. Digital images were processed automatically with operator supervision so that any tracking errors could be rectified and manual tagging of all shots added. Four separate experiments were used to assess the error associated with tracking adult players' velocities and positions with respect to the court floor. Experiment 1 involved players standing still in different areas of the court. The tracking software was found to be more accurate when a player was stood in the centre of the court (1.33 m · min?1 error) than in the corners (2.61 m · min?1 error), predominately due to systematic errors (e.g. calibration). Experiment 2 was conducted in the same manner as Experiment 1 except that the players vigorously swung a racket around their body continuously. This resulted in 15 times the error found in Experiment 1 for the distance covered during 1 min. However, this is an unrealistic estimate of the true error when assessing matches, as during matches the racket is only swung approximately 35% of the time. Experiment 3 involved a player running at different speeds around a rectangular path on the court. The resultant trajectory, as captured by the software, was compared using different Gaussian smoothing equations of kernel widths 0.25 s, 0.5 s, and 1 s. The best solution (0.5 s) resulted in the most accurate trajectory, although the difference in distance calculated between the different equations was negligible. Experiment 4 used the 0.5-s smoothing equation to assess the tracking accuracy for a player running at a relatively steady speed in a more realistic circular trajectory. The trajectory of the pixel image was shown to have a smaller radius than the reference trajectory at increased speeds, due to the tendency of the player to lean over when negotiating a circular path. The error associated with the distance covered over 1 min was shown to range between 1.33 and 21 m depending on the nature and position of the player's movements. Values, typically somewhere in this range, are likely to be evident during typical use of this software.  相似文献   

20.
Experiment 1 examined whether it is more advantageous to direct learners' attention to the external effects of their movements relative to other external cues. Two groups of participants hit tennis balls at a target, with one group focusing on the ball coming toward them (antecedent) and the other group focusing on the ball leaving the racket (effect). The effect group demonstrated more effective learning. Experiment 2 examined whether it is more beneficial if the movement effect is related to the movement technique, relative to other movement effects (e.g., outcome). Two groups of participants hit golf balls at a target. The attention of these groups was directed to the club or the ball trajectory, respectively. The club group showed more effective learning than the target group, suggesting that focusing on technique-related effects is more effective.  相似文献   

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