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981.
The purpose of this investigation was to determine the abilities of children to use the adjoining mechanism in combining two constituent sentences with the temporal adjoiners: after, before, until, when, and while. To elicit responses, a sentence repetition task was devised that included these five temporal adjoiners in four different syntactic environments: transitive sentences with the adjoiner and the subordinate clause following the main clause, transitive sentences with the adjoiner and the subordinate clause preceding the main clause, intransitive sentences with the adjoiner and the subordinate clause following the main clause, and intransitive sentences with the adjoiner and the subordinate clause preceding the main clause. The 30 were between the ages of 4O and 66 years. They were average children who were free from any known emotional disturbance, who were acquiring Standard American English as a native language, who had normal speech and hearing, and whose parents had neither very high nor very low socioeconomic status. To the extent that the children in this study were representative of normal-speaking children of their ages, certain general conclusions were drawn. Children begin to use the temporal adjoining mechanism early, but they do not master it by the age of 66 years. The ability to use the adjoiners, nor is it equal for different syntactic structures nor for all degrees of semantic complexity. After, before, and when appear earlier than while and until. A rapid period of growth in learning to use the temporal adjoining mechanism occurs between the ages of 4 and 5 years. However, a plateau of learning appears to be reached between the ages of 5 and 6 years. In general, children first learn to use the temporal adjoining mechanism in intransitive sentences with the adjoining link in the middle or at the beginning of the utterance. Next, they learn to use it in transitive sentences with the adjoining link at the beginning of the utterance. Finally, they learn to use it in transitive sentences with the adjoining link in the middle of the utterance. In transitive sentences, children appear to learn the rule for placing the subordinate clause at the beginning of the utterance when temporally adjoining two constituent sentences before they learn the base structure rule. In intransitive sentences, they appear to learn the rule for placing the subordinate clause at the beginning of the utterance when temporally adjoining two constituent sentences at the same time that they learn the base structure rule. The underlying semantic relationships that are expressed by specific temporal adjoiners are important determinants of children's abilities to use these adjoiners. In linguistic evaluations, one should consider the syntactic environment in which the temporal adjoiner occurs and assume that after, before, and when are developmentally earlier than while and until.  相似文献   
982.
Rats shocked once through a wire-wrapped stationary prod mounted on the wall of a test chamber incorporated the bedding material covering the chamber floor into a defensive reaction. When tested 1 min later, they approached the prod and buried it. Evidence was provided by three separate studies of this burying response that rats had learned about the association of both the position and brightness of the prod with shock after this single conditioning trial. In Experiment 1, the amount of burying decreased if either the position or brightness of the prod had been changed prior to the test. In Experiments 2 and 3, rats were shocked through one of two prods (white or black) mounted on opposite walls of the test chamber. When the positions of the prods were unchanged for the test, almost every subject buried the prod through which it had been shocked, even when the conditioning-test interval was 24 hr; whereas, each rat directed substantial amounts of bedding material at both prods when the positions of the two prods were reversed. Thus, discriminated “avoidance” learning can be rapid, reliable, and enduring when shock is administered “by” a clearly defined stimulus object, i.e., when cue and consequence are spatially contiguous.  相似文献   
983.
984.
This article explores the legal, ethical, and practical considerations underlying the requirement for acquiring parental consent prior to a psychological assessment of children in school settings. Publ. L. 94-142 now mandates that parents for all children potentially labeled as handicapped give permission for a preplacement evaluation. This article reviews in detail specific aspects of that mandate, argues that this procedure be generalized to all situations where psychologists propose to evaluate children by reviewing both current ethical codes and standards for practice and public policy which favors such an undertaking. Finally, the authors indicate methods for implementing the mandate by discussing such issues as who should obtain consent and what information parents should receive prior to giving consent.  相似文献   
985.
People recall taboo words better than neutral words in many experimental contexts. The present rapid serial visual presentation (RSVP) experiments demonstrated this taboo-superiority effect for immediate recall of mixed lists containing taboo and neutral words matched for familiarity, length, and category coherence. Under binding theory (MacKay et al., 2004), taboo superiority reflects an interference effect: Because the emotional reaction system prioritizes binding mechanisms for linking the source of an emotion to its context, taboo words capture the mechanisms for encoding list context in mixed lists, impairing the encoding of adjacent neutral words when RSVP rates are sufficiently rapid. However, for pure or unmixed lists, binding theory predicted no better recall of taboo-only than of neutral-only lists at fast or slow rates. Present results supported this prediction, suggesting that taboo superiority in immediate recall reflects context-specific binding processes, rather than context-free arousal effects, or emotion-linked differences in rehearsal, processing time, output interference, time-based decay, or guessing biases.  相似文献   
986.
The likelihood of benefit is fundamental to decision making about newborn screening. But benefit is construed in different ways by different stakeholders. This article begins with a review of benefit as considered historically by various expert panels and organizations. We then show how 78 conditions fared when experts recently rated them on benefit using a scoring system recommended by a task force of the American College of Medical Genetics. Finally, we analyze how benefit is reflected in the public comments submitted in response to the ACMG report. Results show that benefit has been and remains a core consideration for screening decisions. Historically the focus has been on improved physical health as a result of medical treatment; however, in only 4 of the 78 conditions rated does newborn screening prevent all negative consequences. In fact the majority of both core conditions (51.7%) and secondary targets (87.5%) recommended in the ACMG report were rated as having treatments that prevented only some negative consequences. All conditions rated had perceived benefits for family and society, but currently no conditions are screened on the basis of family or societal benefits alone. No agreed-upon threshold exists for what would be considered meaningful benefit, and stakeholder groups differ in their perceptions of benefit. We conclude by suggesting several key research studies needed to further inform public policy.  相似文献   
987.
988.
989.
Event-related potentials to critical verbs were measured as patients with schizophrenia and healthy controls read sentences word by word. Relative to their preceding context, critical verbs were (a) congruous, (b) incongruous and semantically unrelated to individual preceding words (pragmatic-semantic violations), (c) incongruous but semantically related to individual preceding words (animacy-semantic violations), or (d) syntactically anomalous. The N400 was modulated normally in patients, suggesting that semantic integration between individual words within sentences was normal in schizophrenia. The amplitude of the P600 to both syntactic and animacy-semantic violations was reduced in patients relative to controls. The authors suggest that, in schizophrenia, an abnormality in combining semantic and syntactic information online to build up propositional meaning leaves sentence processing to be primarily driven by semantic relationships between individual words.  相似文献   
990.
Many of Meehl's interests converged in his work on personality assessment. In empirical research, development of the K scale of the Minnesota Multiphasic Personality Inventory and various scales of other tests are noteworthy, but his most profound contributions were conceptual and philosophical. Essays on the role of base rates in clinical decision and on construct validity in psychological tests provided vital insights on core issues in assessment. The concept of nomological nets allowed systematic investigation of unobservable theoretical entities, with liberating effects on all natural sciences. An active clinician, Meehl understood deeply the complexities of professional service, but his insistence on empirical validation as the ultimate arbiter of the value of any procedure required all attainable rigor in the scientific foundations of clinical practice.  相似文献   
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