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981.
982.
The number, amplitude, duration, and bout structure of isolation-induced ultrasonic vocalization (USV) of infant rats (Rattus norvegicus) were measured on postnatal Day 10. Measurements were made before and after a brief, 1-min, active interaction with their mother or before and after a "pick-up" control procedure. Consistent with prior studies, the number of USVs emitted was significantly increased in the period following the maternal reunion but not after the control procedure. The average amplitude of USVs was also greater following maternal reunion. Finally, analyses characterizing the bout structure of USV production indicated that the average bout size (i.e. number of USVs/bout) was increased severalfold following the reunion with the mother, accounting for the greater rate of USV production during the second isolation period.  相似文献   
983.
Effects of rate building on fluent performance: a review and commentary   总被引:1,自引:0,他引:1  
The use of rate-building procedures to encourage the production of high response rates and to develop fluency has been increasingly justified by research on precision teaching and automaticity. Rate-building procedures often ensure both speed and accuracy, and claims have been made that such procedures result in greater retention, persistence, and generalization of trained skills, as well as preference by students. Given the potential importance of these claims for behavior analysts and educators alike, this review assesses the validity, generality, and implications of research on rate building. The review revealed sparse empirical evidence that retention, persistence, and generalization of skills result from the use of rate-building procedures when the effects of practice and reinforcement rate are controlled. Given the results of this review, the implications are discussed in the context of behavior-analytic research (e.g., behavioral momentum), and further research is recommended.  相似文献   
984.
In earlier work we have shown that adults, infants, and cotton-top tamarin monkeys are capable of computing the probability with which syllables occur in particular orders in rapidly presented streams of human speech, and of using these probabilities to group adjacent syllables into word-like units. We have also investigated adults' learning of regularities among elements that are not adjacent, and have found strong selectivities in their ability to learn various kinds of non-adjacent regularities. In the present paper we investigate the learning of these same non-adjacent regularities in tamarin monkeys, using the same materials and familiarization methods. Three types of languages were constructed. In one, words were formed by statistical regularities between non-adjacent syllables. Words contained predictable relations between syllables 1 and 3; syllable 2 varied. In a second type of language, words were formed by statistical regularities between non-adjacent segments. Words contained predictable relations between consonants; the vowels varied. In a third type of language, also formed by regularities between non-adjacent segments, words contained predictable relations between vowels; the consonants varied. Tamarin monkeys were exposed to these languages in the same fashion as adults (21 min of exposure to a continuous speech stream) and were then tested in a playback paradigm measuring spontaneous looking (no reinforcement). Adult subjects learned the second and third types of language easily, but failed to learn the first. However, tamarin monkeys showed a different pattern, learning the first and third type of languages but not the second. These differences held up over multiple replications, using different sounds instantiating each of the patterns. These results suggest differences among learners in the elementary units perceived in speech (syllables, consonants, and vowels) and/or the distance over which such units can be related, and therefore differences among learners in the types of patterned regularities they can acquire. Such studies with tamarins open interesting questions about the perceptual and computational capacities of human learners that may be essential for language acquisition, and how they may differ from those of non-human primates.  相似文献   
985.
Studies of patients with category-specific agnosia (CSA) have given rise to multiple theories of object recognition, most of which assume the existence of a stable, abstract semantic memory system. We applied an episodic view of memory to questions raised by CSA in a series of studies examining normal observers' recall of newly learned attributes of familiar objects. Subjects first learned to associate arbitrarily assigned colors or textures to objects in a training phase, and then attempted to report the newly learned attribute of each object in a recall task. Our subjects' pattern of recall errors was similar both quantitatively and qualitatively to the identification deficits among patients with CSA for biological objects. Furthermore, errors tended to reflect conceptually and structurally based confusions. We suggest that object identification involves recruitment and integration of information across distributed episodic memories and that this process is susceptible to interference from objects that are structurally similar and conceptually related.  相似文献   
986.
The authors examined the construct of psychopathy as applied to 130 adolescent offenders using 3 psychopathy measures and a broad range of DSM-TV Axis I diagnoses and psychosocial problems. Measures used in the study included the following: (a) Psychopathy Checklist-Youth Version, (b) Antisocial Process Screening Device, (c) a modified version of the Self-Report Psychopathy-II scale, and (d) the Adolescent Psychopathology Scale. Results from this study offer incremental support for the construct validity of psychopathy in youth. Psychopathy evidenced better convergent and discriminant validity results than did the disruptive behavior disorders (DBDs) such as oppositional-defiant disorder (ODD) and conduct disorder (CD). Despite this finding, psychopathy scales nonetheless correlated with other forms of psychopathology at a higher rate than was expected, suggesting that comorbidity is high even when psychopathy is used as a classification scheme. Also, hierarchical multiple regression was used to determine whether psychopathy offered an improvement in the prediction of previous violent and nonviolent offenses. The results for the current study were mixed, with only the PCL-YV significantly predicting previous violent and nonviolent offenses beyond the DBDs. The findings indicate that psychopathy may offer incremental improvement over DBDs with regard to level of comorbidity and perhaps even prediction. However, simply extending the adult construct of psychopathy to youth without considering the array of psychopathology that may accompany adolescent psychopathy could be misleading.  相似文献   
987.
In the current study, we examined the utility of a procedure consisting of noncontingent reinforcement with and without response cost in the treatment of inappropriate vocalizations maintained by automatic reinforcement. Results are discussed in terms of examining the variables that contribute to the effectiveness of response cost as treatment for problem behavior maintained by automatic reinforcement.  相似文献   
988.
In contemporary psychology, personality assessment knows few national or cultural boundaries. Psychological tests developed in one country are often translated and adapted into cultures that might appear to be greatly different from the country of origin. In this article, I address the factors that are important to international test adaptation and examine problems that can adversely affect cross-cultural test research programs. I address qualities important for verifying the accuracy and adequacy of cross-cultural assessment. I review the extensive adaptation of the MMPI (Hathaway & McKinley, 1940) and MMPI-2 (Butcher, Dahlstrom, Graham, Tellegen, & Kaemmer, 1989), the most frequently used personality measure. I highlight several contemporary research trends in international personality assessment.  相似文献   
989.
This article presents a theory of how individuals reason from inconsistency to consistency. The theory is based on 3 main principles. First, individuals try to construct a single mental model of a possibility that satisfies a current set of propositions, and if the task is impossible, they infer that the set is inconsistent. Second, when an inconsistency arises from an incontrovertible fact, they retract any singularly dubious proposition or any proposition that is inconsistent with the fact; otherwise, they retract whichever proposition mismatches the fact. A mismatch can arise from a proposition that has only mental models that conflict with the fact or fail to represent it. Third, individuals use their causal knowledge-in the form of models of possibilities-to create explanations of what led to the inconsistency. A computer program implements the theory, and experimental results support each of its principles.  相似文献   
990.
Quality of life of first-degree relatives living in the same household with patients having schizophrenia has not been sufficiently explored. 30 patients with schizophrenia (16 women, 14 men), diagnosed using DSM-IV criteria, 31 of their relatives (15 women, 16 men), and 34 control subjects (21 women, 13 men) were included in the study. The mean age of the patients, their relatives, and the control subects were 39.8 +/- 10.9, 58.1 +/- 12.5 and 37.3 +/- 17.0, respectively. The World Health Oranization Quality of Life-Brief Form was administered to all subjects. Quality of life was worse for the patient group than for their relatives and control subjects, but relatives of the patients and control subjects were not significantly different on Quality of life. Quality of life was negatively correlated with the severity of psychopathology and extrapyramidal side effects induced by antipsychotic drugs in the patients.  相似文献   
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