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221.
Two experiments were performed to test the hypothesis that omission of a previously received reward is followed by greater motivation to obtain that specific reward, as compared with the case where the reward had been present. In Experiment 1, experimental rats regularly received food rewards (Ra) at one goal, followed by a choice between food and milk (Rb). Control animals received the same choice without food preceding it. Reward magnitudes were manipulated so as to produce a preference for Rb, and additional forced trials were given each day to equalise experience of the two rewards. In the test phase both groups received trials with Ra present (R) or absent (N) at the first goal. The experimental Ss shifted their choice towards Ra on N trials; the controls did not behave differently after R and N. Experiment 2 was similar, except that Ra was milk and Rb food. The same effect of N on experimental animals was obtained. It is argued that the results are relevant to the double-runway ‘frustration effect’, and cannot be explained by existing theories of frustration.  相似文献   
222.
A study was designed to assess the contributions of the factors of sex and familial history to cerebral dominance, where cerebral dominance was inferred from laterality on a dichotic listening task. The 144 subjects were selected from a larger sample on the basis of handedness, sex, and familial history of sinistrality, and tested on a task involving the dichotic presentation of CV syllables. Analysis of the data indicated that in female subjects, the presence of familial sinistrality increased the likelihood that they present atypical left-ear superiorities, while in males the converse was the case. Moreover, there was a significant sex difference overall, such that males were more clearly lateralized than females. A review of other dichotic listening studies provided support for the reliability of this sex difference for dichotic tasks using verbal material. A review of the clinical literature indicated that the hypothesis of a sex difference is at least tenable and merits further investigation. However, the possibility that there is a sex difference in the cognitive strategy used in dichotic listening cannot be ruled out.  相似文献   
223.
Two kinds of measures of multivariate association, based on Wilks' and the Bartlett-Nanda-Pillai trace criterionV, respectively, are compared in terms of properties of the univariateR 2 which they generalize. A unified set of derivations of the properties is provided which are self-contained and not restricted to decompositions in canonical variates. One conclusion is that asymmetric index based on allows generalization of the multiplicative decomposition ofR 2 in terms of squared partial correlations, but not the additive decomposition in terms of squared semipartial correlations, while the reverse is true for anasymmetric index based onV.We are indebted to Jos M. F. ten Berge for some fruitful discussions.  相似文献   
224.
This series of experiments examined zero-delay matching-to-sample performance in pigeons with element and compound sample stimuli. In Experiment 1, compound sample stimuli were consistently followed by compound comparison stimuli and matching accuracy during testing was equivalent to element sample-element comparison trials on the color dimension. In Experiment 2, element comparisons suddenly introduced following compound samples produced a decrement on the line dimension only. Subsequent testing at various sample durations revealed higher matching accuracy following element samples than following compound samples on both the color and line-tilt dimensions. Experiment 3 replicated the results of Experiments 1 and 2 and also demonstrated that the superiority of element over compound matching performance remains constant over the sample durations tested. In Experiment 4 testing at sample durations up to 30 sec produced an overall decrement in matching performance, but again the element vs compound matching difference remained constant. The stimulus-generalization decrement hypothesis provided a better explanation of these results than either the information-overload hypothesis or the rule hypothesis.  相似文献   
225.
This paper reports two experiments concerning the effects of word age-of-acquisition and other word attributes on speed of lexical decision. Analyses of group average data indicated that word length, frequency and familiarity were the major determinants of decision speed. Previous reports of age-of-acquisition effects on lexical decision are attributed to failures to control for word familiarity.  相似文献   
226.
Two experiments were conducted to test the effects of making an attribution on later memory for the event that gave rise to the attribution. Subjects in Experiment 1 observed a scenario in which an actor's behavior was associated with high or low variance (distinctiveness) across situations, and high or low congruence (consensus) to the actions of others. Subjects either made attributions for the actor's behavior immediately following the scenario or not. One week later, subjects were asked to recall consensus and distinctiveness for the actor's original behavior. Subjects who made attributions were significantly better at estimating the high-high and low-low combinations of consensus and distinctiveness than were their no-attribution counterparts. It was suggested that making an attribution may allow for a reconstructed memory for the original event, but not enhance direct access to the original event information. A second experiment tested this concept further by having subjects view an edited version of the scenario in which either the distinctiveness or the consensus information was deleted and having subjects make attributions or not. One week later, subjects were asked to indicate their certainty that consensus and distinctiveness information was a part of the original scenario and to estimate the levels of consensus and distinctiveness. Subjects who made attributions were more confident and accurate in estimating the level of consensus or distinctiveness that was given in the original scenario than were no-attribution subjects. However, attribution subjects were also more confident that consensus information or distinctiveness information was contained in the scenario (when it was not) than were the noattributio subjects. Results of the two experiments suggest that eliciting attributions can distort subsequent memory for the event on which the attributions were based.  相似文献   
227.
Loekie Elbers 《Cognition》1982,12(1):45-63
A case study of the period of repetitive babbling in one child (Dutch) is reported. A cognitive continuity theory is presented, which views repetitive babbling as a systematic, continuous and largely self-directed process of exploration, during which the child uses certain operating principles in the construction of his own ‘springboard’ to speech.Two operating principles identified are: a combination principle, consisting of the combining of articulatory acts which previously have been exercised separately, and a variation principle, consisting of the trying out of the same type of articulatory act in different articulatory contexts.Four stages are distinguished in the development of repetitive babbling. In the first stage no combinations occur, in the second stage combination mainly takes the form of repetition and in the third stage it takes the form of concatenating different babbling types as well. In the fourth stage the concatenations grow more varied and less repetitive in character. The subsequent stages of jargon babbling and first words are discussed shortly and their continuity with repetitive babbling is pointed out.  相似文献   
228.
Two experiments explored variation in the alerting process across age and warning interval as well as the effects of alertness on subsequent processing. Experiment 1 obtained alertness functions for a group of 5-year-olds, 8-year-olds, and adults. Results revealed strong age differences in speed of alerting and in maintenance of alertness over a 1-sec interval. Five-year-olds alerted more slowly than older groups and sustained optimal alertness less well. Both groups of children showed more variability in alerting functions compared with adults. Experiment 2 examined the degree to which age differences in processing speed were attributable to differential speed and maintenance of alerting. Masking functions obtained across variations in the alerting interval revealed that when level of alertness was optimal in both 5-year-olds and adults, minimal age differences in processing speed were observed. During short, nonoptimal alerting intervals, speed of processing in adults was faster than in 5-year-old children. The pattern of results across studies suggested that alertness can fluctuate over time in young children, that level of alertness affects subsequent perceptual processing speed, and that developmental variation in speed and maintenance of alertness can partly explain observed age differences in processing speed. The potential role of alertness in more complex cognitive tasks is discussed.  相似文献   
229.
This study investigated a wide range of communicative hand/arm gestures of 4-year-old males when interacting with their mothers. The types of gesture categories observed were in keeping with the predicted encoding ability of this aged child. Pantomimic and deictic gestures were observed in significantly greater numbers than semantic modifying and relational gestures. Although it was found that the mothers' gestural usage reflected the type of gesture categories seen in the children's group, no correlation was found between gesture usage of individual mother-child pairs.  相似文献   
230.
A 41-year-old male patient is presented with a lesion in the anterior cingulate cortex, medial orbital cortex, and rostral striatum bilaterally and supplementary motor area on the left side. The patient first exhibited a state of akinetic mutism which lasted about 6 weeks. During this state, no volitional vocal utterances were made; there were, however, occasional groans of pain. During recovery, the mute phase was replaced by a state in which the patient could whisper but not phonate verbal utterances. About 10 weeks after the accident, phonation was restored. The speech was characterized, however, by monotonous intonation and a very low frequency of spontaneous utterances. While the frequency of spontaneous speech improved noticeably during the following months, emotional intonation remained permanently defective. A comparison of the present case with other cases from the literature as well as experimental monkey data suggest that the anterior cingulate cortex is involved in the volitional control of emotional vocal utterances.  相似文献   
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