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961.
This paper re-examines two hypotheses on the ontogeny of hemispheric specialization that long ago fell into disfavor in neuropsychology. It is argued that these hypotheses, equipotentiality and progressive lateralization, may have suffered from misinterpretation that fostered premature acceptance of the developmental invariance view of hemispheric specialization. An alternative view is presented that incorporates both hypotheses within a neurodevelopmental context using anatomical (postmortem) and childhood aphasia data. 相似文献
962.
Benzodiazepine receptor ligand influences on acquisition: suggestion of an endogenous modulatory mechanism mediated by benzodiazepine receptors 总被引:2,自引:0,他引:2
In rats, pretraining ip administration of the central benzodiazepine receptor antagonist, flumazenil (5.0 mg/kg), or of the inverse agonist, n-butyl-beta-carboline-3-carboxylate (BCCB) (0.2 or 0.5 mg/kg), facilitated retention of a step-down inhibitory avoidance task; the central agonists, clonazepam and diazepam (0.4 or 1.0 mg/kg), had an opposite effect, and the peripheral agonist, 4'-chlordiazepam (1.25 or 6.25 mg/kg), was without effect. Pre- but not post-training flumazenil (2.0 mg/kg) blocked the effect of BCCB (0.5 mg/kg), clonazepam (1.0 mg/kg), or diazepam (1.0 mg/kg) given also pretraining. The post-training administration of all of these drugs had no effect on retention of the avoidance task. Flumazenil (5.0 mg/kg) and BCCB (0.5 mg/kg), given before training, enhanced retention test performance of habituation to a buzzer but not of habituation to an open field. In the three tasks studied, none of the drugs used had any appreciable effect on training session parameters. These results suggest that there is an endogenous mechanism mediated by benzodiazepine agonists, sensitive to inverse agonists, that normally down-regulates acquisition of certain behaviors; this mechanism becomes activated only when the tasks involve or occur with a certain degree of stress or anxiety (i.e., inhibitory avoidance or habituation to the buzzer) and not in less stressful or anxiogenic tasks (i.e., habituation to an open field). 相似文献
963.
This report reviews the literature on the values of alcoholics and addicts in treatment and presents data that suggest a shift in values is involved in recovery from alcoholism through participation in Alcoholics Anonymous and that values clarification and value therapy may be useful in chemical dependency treatment. 相似文献
964.
965.
James M. Dabbs Jr Charles H. Hopper Gregory J. Jurkovic 《Personality and individual differences》1990,11(12)
Relationships of serum and saliva to personality were examined among 401 college students in four laboratory studies and 5,236 military veterans in one archival study. Among the students, there were few relationships between testosterone and traditional personality measures. Among the veterans, MMPI scores and DSM-III diagnoses showed testosterone related to drug and alcohol abuse, antisocial and generally intemperate behavior, and effective disorders. Consistent with social control theory, correlations were higher among veterans who were lower in socioeconomic status. It appears likely that testosterone has innate effects that are socially undesirable but can be attenuated by bonds between the individual and society. Effect sizes were small, suggesting that testosterone will have noticeable effects only in large populations or individuals who differ markedly from the population mean. Further research should focus upon antisocial correlates of testosterone and conditions that produce marked changes in testosterone levels. 相似文献
966.
Conclusion The world contains not only causes and effects, but also causal relations holding between causes and effects. Because causal relations enter into the structure of the world, their presence has various modal and probabilistic consequences. Causation and necessary and sufficient conditions do often go hand in hand. Causation, however, is a robust ingredient within the world itself, whereas modalities and probabilities supervene on the nature of the world as a whole, and on the resulting relations between one possible world and others. Some modalities, therefore, are essentially causal; but causation is not essentially modal.19 相似文献
967.
James Robert Brown 《国际科学哲学研究》1990,4(2):117-130
Proofs and Refutations is Lakatos's masterpiece. This article investigates some of its central themes, in particular: the nature of proofs ('Proofs do not prove, they improve'); the nature of definitions (real, not nominal); and the consequences of all this for ontology (platonism vs Popper's World Three). 相似文献
968.
D. H. Mellor 《国际科学哲学研究》1990,4(2):159-170
The paper develops a unified account of both deterministic and indeterministic laws of nature which inherits the merits but not the defects of the best existing accounts. As in Armstrong's account, laws are embodied in facts about universals; but not in higher‐order relations between them, and the necessity of laws is not primitive but results from their containing chances of 0 or 1. As in the Ramsey‐Lewis account, law statements would be the general axioms and theorems of the simplest deductive theory of everything; but because laws are not so defined, simplicity of statement is not a criterion of law‐hood. 相似文献
969.
Efficacy of behavioral management and patient education on vascular access cleansing compliance in hemodialysis patients 总被引:1,自引:0,他引:1
Compared four treatment conditions to test their ability to enhance compliance with vascular access cleansing (VAC) procedures in a group of 56 hemodialysis patients. The conditions were patient education, behavioral management with monetary incentive, patient education/behavioral management, and attention control. Behavioral observers rated VAC behavior at pretreatment, posttreatment 1-month follow-up, and 1-year follow-up. Knowledge of VAC procedures was also assessed via a questionnaire at pretreatment and posttreatment. Data were analyzed using repeated-measures multivariate analyses of variance. Results indicated that the patients in the education/behavioral, behavioral, and education groups gave significantly more correct answers on our VAC knowledge questionnaires at posttreatment than did patients in the attention control group. Further, patients in the education/behavioral and behavioral groups completed significantly more VAC steps at posttreatment and 1-month follow-up than did patients in the education group and in the attention control group. Differences were not maintained at 1-year follow-up, although more than 50% of the patients were lost to follow-up. Implications of the present findings for behavioral and educational interventions are discussed. 相似文献
970.
Peter N. Kugler Robert E. Shaw Kim J. Vincente Jeffrey Kinsella-Shaw 《Psychological research》1990,52(2-3):98-121
Summary The role of intention in guiding the behavior of goal-directed systems is a problem that continues to challenge behavioral science. While it is generally agreed that intentional systems must be consistent with the laws of physics, there are many obvious differences between inanimate, physical systems and sentient, intentional systems. This suggests that there must be constraints over and above those of physics that govern goal-directed behavior. In this paper it is suggested that generic properties of self-organizing mechanisms may play a central role in the origin and evolution of intentional constraints. The properties of self-organizing systems are first introduced in the context of simple physical systems and then extended to a complex (biological) system. Whereas behavior of an inanimate physical system is lawfully determined by force fields, behavior of an animate biological system is lawfully specified by information fields. Biological systems are distinguished from simple physical systems in terms of their ubiquitous use of information fields as special (biological and psychological, social, etc.) boundary conditions on classical laws. Unlike classical constraints (boundary conditions), informational constraints can vary with time and state of the system. Because of the nonstationarity of the boundary conditions, the dynamic of the system can follow a complex trajectory that is organized by a set of spatially and temporally distributed equilibrium points or regions. It is suggested that this equilibrium set and the laws that govern its transformation define a minimal requirement for an intentional system. One of the benefits of such an approach is that it suggests a realist account for the origin of semantic predicates, thereby providing a basis for the development of a theory of symbolic dynamics. Therefore, the principles of self-organization provide a comprehensive basis for investigating intentional systems by suggesting how it is that intentions arise, and by providing a lawful basis for intentional behavior that reveals how organisms become and remain lawfully informed in the pursuit of their goals. 相似文献