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121.
The present study is concerned with the perceptual information about the body and space underlying the act of catching a ball. In a series of four experiments, subjects were asked to catch a luminous ball under various visual conditions. In general, catching in a normally illuminated room was contrasted with catching the luminous ball in an otherwise completely dark room. In the third and fourth experiments, intermediate conditions of visual information were included. The results suggest that it is possible to catch a ball with one hand when only the ball is visible, but performance is better when the subject has the benefit of a rich visual environment and two hands. The second experiment indicated that subject performance does improve with practice in the dark, but time spent in the darkened room itself doesn't result in a significant decrement in performance. Results of the third study suggest that vision of one's hand does not aid in the performance of this task whereas the presence of a minimal visual frame appears to aid performance. The final study examined the relation between catching performance and body sway under similar visual conditions. Results of this experiment imply that persons who exhibit relatively little postural sway in full-room lighting performed better at this catching task.  相似文献   
122.
123.
The kinematic parameters of to and fro forearm movements in the horizontal plane were investigated in 5- to 7-year-old boys. In one condition, the period of the movements was induced by an acoustic stimulus, while the amplitude was left free. In a second condition, the amplitude of the swing was suggested by a visual frame, but the movement was self-paced. In both conditions, the unconstrained variable (amplitude and period, respectively) was found to covary spontaneously with the constrained variable. The results suggest that, within the age range considered here, motor control processes do not conceive of amplitude and velocity as two independent variables.  相似文献   
124.
The influence of positive and negative moods on children's recall and recognition memory and impression-formation judgments was investigated in a two-list experimental design. A total of 161 schoolchildren, 8 to 10 years old, were presented with audiovisual information containing positive and negative details about 2 target children. Each presentation was preceded by happy or sad mood manipulations. One day later, the children were again placed in a happy or sad mood, and their recall and recognition memory and impression-formation judgments were assessed. Results showed that memory was better when (a) the children felt happy during encoding, retrieval, or both; (b) the material was incongruent with learning mood; (c) the 2 target characters were encountered in contrasting rather than in matching mood states; and (d) recall mood matched encoding mood. A happy mood increased the extremity of both positive and negative impression-formation judgments. Results are contrasted with experimental data obtained with normal or depressed adults, and implications are considered for contemporary theories of mood effects on cognition and for social-developmental research.  相似文献   
125.
Speech nonfluency in response to questions about the marital relationship was used to assess anxiety. Subjects were 31 husbands and 31 wives, all white, college educated, from middle- to lower-middle-class families, and ranging from 20 to 30 years of age. Three types of nonfluencies were coded: filled pauses, unfilled pauses, and repetitions. Speech-disturbance ratios were computed by dividing the sum of speech nonfluencies by the total words spoken. The results support the notion that some issues within marriage are more sensitive and/or problematic than others, and that, in an interview situation, gender interacts with question content in the production of nonfluencies.  相似文献   
126.
This study was conducted to examine the effectiveness of using voice tones (prosody) typical of "motherese" (O. K. Garnica, 1977, in C. E. Snow & C. A. Ferguson (Eds.), Talking to Children: Language Input and Acquisition, pp. 63-88, Cambridge: Cambridge Univ. Press) on responsiveness and eye gaze in children with severe handicaps. Specifically, two conditions, "motherese" and "conversational" voice tones, were compared. The current study presents data from naturalistic observations of six children, and controlled experimental manipulations with four children. The results of the naturalistic observations in Study 1 suggested a positive relationship between the use of voice tones typical of "motherese" and responsiveness and eye gaze. Further analysis using an alternating treatments design in Study 2 revealed similar results. Specifically, the use of prosody associated with "motherese" showed increased levels of eye gaze when compared to the use of "conversational tones." The results suggest the importance of considering normal development in analyzing social and teaching interactions between teachers and severely handicapped children.  相似文献   
127.
Children's perception of scale and contour in melodies was investigated in five studies. Experimental tasks included judging transposed renditions of melodies (Studies 1 and 3), discriminating between transposed renditions of a melody (Study 2), judging contour-preserving transformations of melodies (Study 4), and judging similarity to a familiar target melody of transformations preserving rhythm or rhythm and contour (Study 5). The first and second studies showed that young children detect key transposition changes even in familiar melodies and they perceive similarity over key transpositions even in unfamiliar melodies. Young children also are sensitive to melodic contour over transformations that preserve it (Study 5), yet they distinguish spontaneously between melodies with the same contour and different intervals (Study 4). The key distance effect reported in the literature did not occur in the tasks of this investigation (Studies 1 and 3), and it may be apparent only for melodies shorter or more impoverished than those used here.  相似文献   
128.
We examined the functional role of verbalizations in the generalization of self-instructional training with preschoolers. Children learned to overtly self-instruct during classroom work periods prior to covert training. Data were collected on children's acquisition of verbal regulation during training and on overt use of self-instructions in the classroom generalization setting. Results of a multiple baseline design across subjects indicated that treatment effects were evident in the training setting but did not generalize to the classroom until children were emitting overt self-instructions in the classroom itself. The production of self-verbalizations in the generalization setting was related to changes in correct responding, on-task behavior, and efficiency in completing academic work.  相似文献   
129.
130.
Using a multi-trial, free-recall paradigm (Rey Auditory-Verbal Learning Test; Lezak, 1983), the acquisition and retention by learning disabled (LD) young adults with a Halstead Impairment Index less than or equal to 0.3 (low LD) or greater than or equal to 0.4 (high LD) was compared with that of nondisabled and head-injured (HI) young adults. Significant group differences, particularly during the last three acquisition trials, confirmed the effectiveness of this method in revealing subtle learning and retention deficits. Analyses of Trial 1 recall showed group differences in the prerecency but not the recency portion of the serial position curve, thus implicating long-term but not short-term memory differences between the groups. Analyses of pair frequency (Sternberg & Tulving, 1977) data showed that the three clinical groups had difficulty organizing the to-be-learned material for effective retrieval. Following an interpolated task, retention was poorer for the clinical groups than for the nondisabled and varied inversely with the degree of neuropsychological impairment. Finally, during retention, the nondisabled and low LD groups retained and used the list organization established during acquisition whereas the high LD and HI groups did not.  相似文献   
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