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101.
102.
One of the more important and emerging fields in which psychologists collaborate with other disciplines is psychoimmunology. Centuries of clinical anecdote and decades of psychosomatic hypotheses have gained credibility in the eyes of the medical establishment—and many patients—by the systematic investigation of mechanisms potentially explaining how events intrapsychic and interpersonal could affect physical disease processes. The central nervous system is connected with the immune system by both neuronal and endocrinological pathways. The immune system has been found to mediate the organism’s response to aberrations of its own normal functions, as well as to invading organisms from without. AIDS, arthritis, asthma, lupus, and herpes are some of the illnesses in which research is demonstrating important relationships among psychosocial and immunological factors and disease course. In this article, we first discuss the immunological apparatus in order to provide a base for subsequent discussions of the effects of stress on immune function. Then we discuss malignant diseases and current evidence that disease course is related to both psychosocial stressors and immune function. We next discuss a model of these interactions, and finally we talk about interventions incorporating psychosocial factors aimed at influencing immune status and, thus, disease course.  相似文献   
103.
Seventy-five patients admitted to the psychiatric unit of a general hospital were administered a brief neuropsychological screening battery. Discharge diagnoses obtained from the medical records revealed that 20% had brainbased pathology. A discriminant function analysis resulted in a five-variable model (Symbol-Digit Modalities Test, educational level, Psychiatric-Organic subscale of the MMPI, and Shipley Vocabulary and Abstraction scores) which correctly classified 84% of the subjects, with 87% correct identification of the brain-damaged group. A jackknife cross-validation procedure resulted in comparable hit rates.  相似文献   
104.
105.
Adherents to the traditional model of alcoholism explain alcoholic behavior as a consequence of alcoholism. Alcoholism is identified as an unseen, unmeasured entity inherent in alcoholics. This concept parallels the thinking of Copernicus, Kepler, Galileo, and Newton, who believed in an unseen, unmeasurable creator behind the physical world. These traditional approaches contrast with the emergent model of alcoholism and twentieth-century scientific thought. Emergent scientific model adherents explain alcoholic behavior without resort to unseen factors. Since the traditional and emergent scientific models begin with different assumptions, model adherents experience communication difficulties. Future developments with determine which model will dominate the field of alcohol studies and treatment.  相似文献   
106.
School psychologists serving a national, systematic sample of public elementary and secondary schools were surveyed regarding recent referrals. Most referrals were initiated by school staff members (75% of referrals), and the majority occured initially through formal mechanisms (55% of referrals). Most informal requests for assistance or information eventually became, or were thought likely to become, formal referrals. In 92% of cases, the referral agent's initial communication with the psychologist included some designation of what the pupil was doing or not doing that was viewed as problematic. Poor academic performance was of primary concern in 52% of referrals and social/emotional problems in 31%. More boys were referred than girls, and one-half of referrals from the elementary grades involved pupils in grades K-2. Frequency of referral and reason for referral were not independent of pupil's grade or sex. Reason for referral was independent of time of year (October vs. May) and geographical region.  相似文献   
107.
Six pigeons were trained in a discrete-trials signal-detection procedure to discriminate between a fixed-duration stimulus (5 s or 20 s) and a set of variable durations ranging from 2.5 s to 57.5 s in steps of 5 s. For each fixed-duration stimulus, the ratio of reinforcer frequencies contingent upon reporting the fixed versus the variable stimulus was systematically manipulated. Detection performance was well controlled by both the stimulus value and the reinforcer ratio. Both the discriminability between the fixed duration and the set of variable durations, and the discriminability between the fixed duration and each of the variable durations, were independent of the reinforcer-frequency ratio when discriminability was measured as log d. The sensitivity of response bias to reinforcement-ratio changes was independent of the value of the fixed duration, but was not independent of the discriminability of the variable durations from the fixed durations. Under current models, discriminability measures in complex temporal discrimination may be independent of biasing manipulations, but bias measures are not independent of stimulus values.  相似文献   
108.
Pigeons' choices between alternatives that provided different percentages of reinforcement in mixed schedules were studied using the concurrent-chains procedure. In Experiment 1, the alternatives were terminal-link schedules that were equal in delay and magnitude of reinforcement, but that provided different percentages of reinforcement, with one schedule providing, reinforcement twice as reliably as the other. All pigeons preferred the more reliable schedule, and their level of preference was not systematically affected by variation in the absolute percentage values, or in the magnitude of reinforcement. In Experiment 2, preference for a schedule providing 100% reinforcement over one providing 33% reinforcement increased systematically with increases in the duration of the terminal links. In contrast, preference decreased systematically with increases in the duration of the initial links. Experiment 3 examined choice with equal percentages of reinforcement but unequal delays to reinforcement. Preference for the shorter delay to reinforcement was not systematically affected by variation in the absolute percentage of reinforcement. The overall pattern of results supported predictions based on an extension of the delay-reduction hypothesis to choice procedures involving mixed schedules of percentage reinforcement.  相似文献   
109.
Effects of delayed conditioned reinforcement in chain schedules.   总被引:3,自引:3,他引:0  
The contingency between responding and stimulus change on a chain variable-interval 33-s, variable-interval 33-s, variable-interval 33-s schedule was weakened by interposing 3-s delays between either the first and second or the second and third links. No stimulus change signaled the delay interval and responses could occur during it, so the obtained delays were often shorter than the scheduled delay. When the delay occurred after the initial link, initial-link response rates decreased by an average of 77% with no systematic change in response rates in the second or third links. Response rates in the second link decreased an average of 59% when the delay followed that link, again with little effect on response rates in the first or third links. Because the effect of delaying stimulus change was comparable to the effect of delaying primary reinforcement in a simple variable-interval schedule, and the effect of the unsignaled delay was specific to the link in which the delay occurred, the results provide strong evidence for the concept of conditioned reinforcement.  相似文献   
110.
This paper provides a comprehensive formulation of Erik Erikson's theory of ego identity formation as it pertains to both the identity stage and to the remainder of the life cycle. The structure of the identity stage is discussed in terms of its more universal features and in terms of features more specific to North American society. The role played by “institutionalized moratoria” in influencing the outcome of the identity crisis and subsequent development is discussed in the context of two Eriksonian notions ignored in the literature: the value orientation stages and the struggle between the ego and superego for dominance of the personality. As part of the discussion, several constructive criticisms of Erikson's work are offered with the intent of making the theoretical formulation presented in this paper an appropriate basis for subsequent empirical investigations of his theory. One of the important implications of this paper is that it suggests that questions should be raised regarding the validity of the dominant research strategy currently in use.  相似文献   
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