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831.
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   
832.
Lists of eight nonsense syllables were monaurally presented to right-handed men and women for free recall, half to each ear on each trial. Results showed a right-ear advantage (REA) in the recall of recency items, but not primacy items and for males only. Among males only that subgroup without familial sinistrality demonstrated the REA. Results offer support for the following: (A) the language mechanisms involved in short-term “echoic” memory are particularly well-lateralized; (B) mechanisms underlying monaural REAs may be similar to those responsible for the asymmetries found in other paradigms; (C) processing demands and strategies inherent to the monaural technique may account in part for its limited reliability in yielding REA and for the present absence of REA among females.  相似文献   
833.
Two colours were either simultaneously or successively presented. In both cases the time taken to determine whether the colours differed increased as the visual similarity of the colours increased. In another experiment, colours or names of colours were presented successively in different blocks of trials. Here colour similarity affected the discrimination reaction times whenever the second stimulus was a colour. This was taken to suggest that visual mnemonic representations can be generated from the first stimulus.  相似文献   
834.
Two implications of best-example theory for category acquisition were considered. The first is that categories which people acquire based on initial exposure to good exemplars should be learned more easily and (at first) more accurately than categories based on initial exposure to poor exemplars. The second is that people should generally learn that the best exemplars are category members, before learning that the poor exemplars are category members. These implications are based on the premise that people generalize based on similarity, and that the best example has maximal within-category similarity and minimal extra-category similarity, while the poor examples have minimal within-category similarity and relatively high extra-category similarity. Both implications were strongly supported by the present research. It was also found that when pressure to communicate was removed, comprehension and production of category names were virtually identical. The predictions of best-example theory concerning the conceptual structures underlying the words used by children who are just beginning to talk were discussed briefly. This research also allowed the replication of several important categorization results which had previously been found with real-world categories, with a set of artificial concrete object categories.  相似文献   
835.
Relative deprivation theory centers around the proposition that the negative affect associated with judgments of one's own status is not simply a function of one's objective status. Instead, resentment, anger, dissatisfaction and other deprivation-related emotions vary with the subjective assessment of one's status. In the present experiment, subjects read vignettes in which the hypothesized preconditions of felt deprivation were manipulated. They then indicated the degree of perceived resentment and related cognitive-emotional factors attributed to the story characters. Perceptions of deprivation become more prevalent when an individual who lacks a desired outcome (X) (a) compares with another who does possess X, (b) feels entitled to X, (c) feels it was once feasible to attain X, and (d) feels it is not feasible to attain X in the future. The results also suggest that certain preconditions, such as the presence of a comparison other and entitlement, act conjunctively in affecting judgments of felt deprivation. Finally, personal control over desired outcomes appears to be important for relative deprivation theory.  相似文献   
836.
Between 24 and 26 children in each of grades 3, 5, 7, 9, and 11 (with mean ages of 8.5, 10.2, 13.0, 15.0, and 16.6 years, respectively) were tested in their ability to solve linear syllogisms, problems such as “John is taller than Mary. Mary is taller than Pete. Who is tallest? John, Mary, Pete.” Response latencies and error rates decreased across grade levels and sessions. Component latencies also generally decreased with increasing age. Four alternative information-processing models were fit to the group latency data at each grade level. These models were (a) a spatial model, according to which people represent the terms of a linear syllogism in the form of a linear spatial array; (b) a linguistic model, according to which linear syllogisms are solved via inferences on functional relations represented by linguistic deep structures; (c) an algorithmic model, according to which people solve linear syllogisms by applying a series of simple, essentially mechanical steps, and (d) a mixed model, which combines selected features of the spatial and linguistic models, and adds new features of its own. The latency data supported the mixed model at each grade level, although in grade 9 the model was not the preferred one until the second session of testing.  相似文献   
837.
The finite “secretory problem” in dynamic programming generates a set of mathematically optimal criteria for search strategies in sequential decisions. One of the limitations on its applicability has been its failure to allow for the uncertainty of whether or not a choice alternative which has been inspected sometime previous to the present, will be “available.” In this paper, extensions of the model are presented which incorporate not only a parameter for the uncertain availability of previous alternatives, but for the uncertain availability of an alternative currently being observed. The paper emphasizes socalled heuristic strategies which may be used to approximate optimal solutions, and which entail very reasonable demands on the processing capacity of the decision-maker. Laboratory realizations and potential applications are discussed.  相似文献   
838.
Three experiments used a flavor-aversion preparation to demonstrate the occurrence of within-compound associations in various conditioning procedures. In Experiment 1 rats first received two separate two-flavor compounds, each followed by a mild US. They then received one element from one compound paired with a strong US and one element from the other compound nonreinforced. A subsequent choice test of the other two flavors from the compounds revealed that the consumption of each test flavor reflected the conditioning history of the element with which it had been paired. Rats drank less of the flavor whose associate had been paired with the strong US than of the flavor whose associate had been nonreinforced. In Experiment 2 within-compound associations were observed using a similar design in a blocking procedure in which one element from each of the two compounds was conditioned previously. Experiment 3 identified within-compound associations in a procedure where reinforced single element presentations were intermixed with nonreinforced compound presentations, as in a conditioned inhibition paradigm. These results suggest that within-compound associations occur in several important conditioning procedures which use multiple CS presentations.  相似文献   
839.
Internals and externals observed a staged videotape presentation that portrayed a “teacher” and a “learner” engaging in a 20-item anagrams task. For externals, any variability (10, 50, and 90% schedule) in the reinforcing behavior of the “teacher” (agent of reinforcement) resulted in significantly greater perceived freedom than when no variability (0 and 100% schedule) occurred in behavior. For internals, perceived freedom was a negative linear function of the amount of reinforcement administered. Internals indicated that they could influence the behavior of the “teacher” in all reinforcement conditions, whereas externals indicated that they could influence only the “teachers” in the variable reinforcement conditions. It was concluded that greater freedom is attributed to a person whose behavior is perceived as congruent with the person's inner disposition.  相似文献   
840.
Subjects made three ratings for each of 30 words, then had an unannounced immediate free recall test and a second test after 1 week. There was no evidence to indicate significantly better retention on either test when the dimensions rated were unrelated as opposed to related. Subjects low on test anxiety performed better overall than subjects who scored high on either the emotionality or worry components of test anxiety. On the delayed test, the test anxiety effect was apparent only when study ratings involved unrelated dimensions (i.e., broad encoding). This interaction is consistent with two conclusions. First, rating related dimensions led to narrow encodings, thus hindering low-anxiety subjects who normally encode broadly. Second, even explicit ratings of unrelated dimensions did not induce high-anxiety subjects to encode more broadly. That the high-anxiety deficit was not overcome even with explicit orienting tasks may indicate inflexibility in deploying memory strategies.  相似文献   
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