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71.
Data relating novelty preference to age for normal children are inconsistent, although a current theory predicts a developmental shift from novelty to familiarity preference in selective learning (D. Zeaman, 1976, in T. J. Tighe & R. N. Leaton (Eds.), Habituation: Perspectives from child development, animal behavior, and neurophysiology (pp. 297–320), Hillsdale, NJ: Erlbaum). Support for this theory, however, has been derived primarily from studies of retardate learning. Normal children's novelty preference was examined within a modified Moss-Harlow (E. Moss & H. F. Harlow, 1947, Journal of Comparative and Physiological Psychology, 40, 333–342) design to compare Zeaman's model with that of S. L. Witryol and W. Wanich (1983, The Journal of Genetic Psychology, 143, 3–8). Each of 16 problems, consisting of three single-stimulus demonstration trials and one two-choice test, was administered to 180 children (mean CA 4, 5.5, and 7 years) in three reward conditions. Novelty was manipulated by varying stimulus familiarization in the demonstration trials. Experiment 1 showed strong preferences for novel over familiar (demonstrated) stimuli at each age. Experiment 2 revealed novelty preference across age levels, two levels of reward contrast, and two levels of task difficulty. It was reasoned that Moss-Harlow tasks designed for normal children typically present a much higher level of difficulty than that intended by researchers. Furthermore, developmental decreases in novelty preference by retardates may derive from (a) transfer of training from prior experiments and (b) specific, repetitive instructions which may have directed attention away from stimulus novelty.  相似文献   
72.
Four experiments examined the control of observing responses by information feedback during visual discrimination learning. Second-grade children participated in Experiment 1; kindergarten, second-, and fifth-grade children were subjects in Experiments 2 and 3, and grade 5 and adult subjects were tested in Experiment 4. In order to view the stimuli, subjects in Experiments 1, 2, and 3 activated lights in viewing boxes; in Experiment 4, stimulus fixations were measured using a corneal reflection technique. Fifth graders and adults observed the discriminative stimuli for longer times on trials following negative feedback than on trials following positive feedback; in contrast, kindergartener's observing was not affected by type of feedback. Second graders showed smaller and less reliable reactions to type of feedback than did older subjects. These results support the view that visual observing is controlled by cognitive processes associated with hypothesis testing.  相似文献   
73.
Relative outcomes in social commerce with peers are potent determinants of cognitions and behavior in young children. Although there has been considerable attention given to the behavioral consequences of social comparisons following the receipt of rewards, there has been less concern with cognitive or affective consequences. Additionally, little is known about the accrued effects of multiple social comparison experiences that may be consistent or inconsistent with one another. In the present study, young children received a constant level of reward but the amount they saw a peer receive was varied. There were two sequences of reward distribution, and in a given sequence children received either the same number of rewards as the peer (=), more (+), or fewer (?). In a 3 × 3 factorial design all possible combinations occurred. A negative inequality in reward distribution, no matter where it fell in a sequence, made children sad and inclined children to distribute fewer rewards to peers. When a sequence contained an initial experience of positive inequality, children decreased subsequent levels of self-reward. Experiencing a comparison that revealed a negative inequality in reward distribution also disrupted children's accuracy in appraising the overall distribution of rewards: even when an initial negative inequality was completely offset by an equivalent experience of positive inequality, children inaccurately concluded that they had received fewer rewards than their peers.  相似文献   
74.
The ability of first- and third-grade children and college adults to make excuse inferences about a speaker's use of an utterance and to modify those inferences appropriately upon receiving later information was examined in four experiments. Short stories containing an utterance by a speaker were read aloud. Utterances in the story were preceded by contextual information that suggested either that the speaker was truthful or making an excuse. Utterances were followed by information that confirmed or disconfirmed the excuse interpretation. The results of Experiment 1 indicated that even first and third graders can make excuse inferences, but these children rarely modify these interpretations upon receiving disconfirming information. In Experiments 2–4 possible reasons for the children's interpretive inflexibility were examined by varying the difficulty of relating the excuse interpretation and succeeding information. Results suggested processing difficulty, as well as an interpretive “set,” contributed to the children's inflexibility.  相似文献   
75.
Pigeons chose between two alternatives that differed in the probability of reinforcement and the delay to reinforcement. A peck on the red key always produced a delay of 5 s and then a possible reinforcer. The probability of reinforcement for responding on this key varied from .05 to 1.0 in different conditions. A response on the green key produced a delay of adjustable duration and then a possible reinforcer, with the probability of reinforcement ranging from .25 to 1.0 in different conditions. The green-key delay was increased or decreased many times per session, depending on a subject's previous choices. The purpose of these adjustments was to estimate an indifference point, or a delay that resulted in a subject's choosing each alternative about equally often. In conditions where the probability of reinforcement was five times higher on the green key, the green-key delay averaged about 12 s at the indifference point. In conditions where the probability of reinforcement was twice as high on the green key, the green-key delay at the indifference point was about 8 s with high probabilities and about 6 s with low probabilities. An analysis based on these results and those from studies on delay of reinforcement suggests that pigeons' choices are relatively insensitive to variations in the probability of reinforcement between .2 and 1.0, but quite sensitive to variations in probability between .2 and 0.  相似文献   
76.
When discriminated interresponse-time (IRT) procedures have been used to assess preference relations among temporally extended operants, deviations from matching have been obtained. Using a yoked-control procedure, the present study found that key pecking in a discriminated IRT procedure has two sources of strength--that arising from the response-reinforcer contingency that is explicitly arranged, and that arising from a stimulus-reinforcer contingency that is a by-product of the explicitly arranged contingency. The key pecking of all lead birds, and that of 3 of the 4 birds exposed to a yoked autoshaping procedure, was controlled by the keylight that signaled the lead birds' criterion IRTs. Because stimulus control of key pecking by the keylight, whether autoshaped or discriminative, fosters deviations from matching, the discriminated IRT procedure does not provide an appropriate basis for conclusions about preference relations among IRTs.  相似文献   
77.
Research is reviewed suggesting that early school age children and older adults demonstrate a similar pattern of performance deficits (relative to the performance of young adults) on memory tasks, raising the possibility that age-related changes in some common factor might account for both memory development and memory decline. It is argued here that whereas “metamemory” theory of memory development does not provide a viable theory of memory decline, Craik's (F. I. M. Craik & M. Byrd, 1982, in F. I. M. Craik & S. E. Trehub (Eds.), Aging and cognitive processes, New York: Plenum; F. I. M. Craik & E. Simon, 1980, in L. W. Poon, J. L. Fozard, L. S. Cermak, D. Arenberg, & L. W. Thompson (Eds.), New directions in memory and aging, Hillsdale, NJ: Erlbaum) attentional deficit theory of memory decline provides a viable theory of memory development as well. Evidence supporting this position is reviewed, and directions for future research are discussed.  相似文献   
78.
The pathological left-handedness syndrome   总被引:3,自引:0,他引:3  
A clinical syndrome of pathological left-handedness (PLH) is proposed to identify the pattern of correlative changes in lateral development associated with early brain injury in some manifest left-handers. This syndrome is believed to be caused by a hemispheric lesion that is predominantly left-sided (or bilateral asymmetric), which onsets before Age 6, and which encroaches upon the critical speech zones of the frontotemporal/frontoparietal cortex. The pattern of changes may include any or all of the following features: shifts in manual dominance, trophic changes in the extremities, transfer of hemispheric speech, and/or intrahemispheric reorganization of visuospatial cognitive functions. Although some of these correlates of PLH have long been known, they have not been recognized as an interrelated pattern of traits that constitute a clinical syndrome. Identification of these individuals, all manifest left-handers, will be shown to have implications for diagnosis/remediation and for models of recovery of function.  相似文献   
79.
Classmate likeability, compromising skill, and temperament (n = 135) and after-school patterns of social interaction (n = 101) were examined for third through seventh grade children who were identified by a binomial probability model as popular, rejected, neglected, or average in the classroom setting. Significant effects were obtained for each type of score. Compared to the other social status groups, popular children were the best liked and rejected children were the least liked; neglected and average children fell between these two extremes. Popular children had higher compromising scores than either rejected or average children, and neglected children had higher scores than rejected children. Compared to average children, rejected children had higher attention and rhythmicity temperament scores. Finally, popular and average children had more neighborhood friends than either rejected or average children, and meglected children had more younger neighborhood friends than did average children. Results are discussed in terms of models of peer social status.  相似文献   
80.
This study examined whether patients with Korsakoff's disease suffer from increased PI during encoding. The ability of the name of one category, e.g., BIRD, to prime the processing of members of another category, e.g., BODY PARTS, in a lexical decision task was used to assess the amount of PI during encoding. This task required a subject to inhibit the normal associations to BIRD. Young normals (25 years), older normals (48 years), alcoholics (45 years), and alcoholic Korsakoff patients (59 years) performed two lexical decision tasks. In the first experiment, the appearance of the neutral prime XXX 750 msec before the probe signaled that if the probe was a word, there was a 75% chance that it was from a particular category (e.g., BODY PARTS). The prime facilitated reaction time for words from the expected category for all four groups. The prime slowed reaction time for words that were not from the expected category for the young normals but did not influence reaction time for unexpected words for the three older groups. The second experiment was identical to the first except that a category word was used as the prime. The category word used as the prime was unrelated to the category of the words that were likely to follow it. For example, BIRD might be used to signal the likelihood that the word would be from the category, BODY PARTS. Again, young normals were slower to respond to unexpected probe words, but the three older groups were not. Again, the prime facilitated reaction time for expected words for the young normals, older normals, and alcoholics. However, the word prime did not facilitate reaction time for expected words for the alcoholic Korsakoff patients. That the word prime did not facilitate reaction time for the Korsakoff patients was viewed as evidence that they were unable to inhibit its normal associations and were more sensitive to PI from these associations than the other subjects.  相似文献   
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