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881.
A multiplicative effect of magnitude and proportion of positive reinforcements on attraction and self-rated feelings was examined. Subjects (N = 270) rated their attraction toward persons associated with one of three reinforcement magnitudes (personality similarity, attitude similarity, and personal evaluations) and one of six proportions of positive reinforcements (.00, .20, .40, .60, .80, and 1.00). Results indicated that the slope of the linear attraction function increased and the Y-intercept decreased with increasing magnitude of reinforcement (p < .05). A similar interaction effect was found on the feelings of the subjects (N = 90) in another experiment. The results were interpreted as added support for Byrne's reinforcement-affect model of interpersonal attraction.  相似文献   
882.
In an arbitrary matching-to-sample procedure, two mentally retarded subjects learned conditional discriminations with two sets of stimuli. Each set included a spoken name (N1 or N2), an object (O1 or O2), and a printed symbol (S1 or S2). One subject selected conditionally (a) O1 upon N1, and O2 upon N2, and (b) S1 upon O1, and S2 upon O2. The other subject selected conditionally (a) S1 upon N1, and S2 upon N2, and (b) O1 upon S1, and O2 upon S2. For both subjects, selections of O1 and S1 produced one type of food, F1; selections of O2 and S2 produced a different type of food, F2. Both subjects also learned identity-matching performances, selecting O1, O2, S1, S2, F1, and F2 conditionally upon those stimuli as samples; F1 followed selections of O1, S1, and F1; F2 followed selections of O2, S2, and F2. Matching performances consistent with stimulus class formation involving the names, objects, symbols, and foods were demonstrated on probe trials, even though these performances had not been taught explicitly. Next, new objects, X1 and X2, were presented on identity-matching trials, producing F1 and F2, respectively. Without further training, X1 was selected conditionally upon N1, S1, and O1, and X2 was selected upon N2, S2, and O2. When the contingencies were changed so that selections of X1 and X2 were now followed by F2 and F1, respectively, X2 was selected conditionally upon N1, S1, and O1, and X1 was selected upon N2, S2, and O2. Class membership of X1 and X2 had apparently changed. This study provides evidence that reinforcers may become members of stimulus classes, and that new stimuli may become class members through relations with reinforcers.  相似文献   
883.
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   
884.
We compared maternal attitudes and feelings in two groups of mother–infant dyads: 25 mothers with preterm newborns (M=30.9 weeks of gestational age) and 25 mothers with fullterm newborns (M=39.7 weeks of gestational age). Both groups were matched for infant sex, age (corrected in preterms) and birth order as well as for maternal age and education. Semi-structured interviews were used to collect data on maternal attitudes and feelings about pregnancy and the first contacts with the newborn. Mothers completed rating scales to indicate the specific behavioural problems they perceived in their infants at 6 weeks and 3 months of (corrected) age. Observations of infant responses to visual and/or auditory stimuli were made at 6 weeks and 3 months in a laboratory setting. At 3 months, each infant was administered the Bayley Scale of Mental Development. There were no differences in maternal attitudes and feelings between the two groups of mothers prior to the birth. However, significant differences appeared after birth and indicated increased anxiety in mothers of preterm infants. Significantly more 6-week-old preterm infants were perceived by their mothers as irritable and to cry more than fullterm infants. At the age of 3 months, both groups of infants differed only in terms of irritability. Differences between the two groups of mother–infant dyads, age-related changes in these differences and relationships between maternal evaluations and the laboratory-based assessments are discussed in the context of contrasts in the stability of behavioural regulation in preterm and fullterm infants.  相似文献   
885.
Citizen advocacy, where a volunteer works in partnership with a vulnerable person, compliments self- and legal advocacy. In the context of mental health services, citizen advocacy is a tool for enabling and empowering people who use these services, and is founded on the recognition that mental health service users are frequently socially oppressed and disadvantaged. This article describes the development of a Citizen Advocacy service for people with mental health difficulties, and also the problems they brought to this service. The problems encountered in sustaining the service are noted and lessons are drawn for the future.  相似文献   
886.
In a time of budgetary shortfalls in the medical industry, an aging population, and an increased emphasis on health care choices, psychologists are being called upon to administer advance medical directive programs to patients. This study reports preliminary findings from a program to assess and facilitate patients' knowledge of advance directives (ADs) by the Psychology Service at the Ann Arbor VA Medical Center. The participant pool included 243 male veteran patients admitted to medical and surgical wards at the hospital. The intervention included the use of a computer-generated prompt for consultation, which was sent to the psychology staff in response to a patient inquiry regarding ADs. It also involved an increased emphasis on the delivery of written material on ADs by the admissions clerks. The intervention appeared to result in a modest increase in patients' knowledge of advance directives. Suggestions are offered for areas that should be emphasized in future attempts to increase patients' knowledge and utilization of advance directives.  相似文献   
887.
Patients with chronic stress and ambiguous symptoms are likely to be more frequent in primary care. Somatizers represent 75.8% of the patients in this study and executives 56% of the sample. Job stressors were present in 78.3% of executive men. This scenario suggests that the primary care physician has to be academically better prepared to fully understand and deal with stress problems in daily clinical practice. The physician must have skills to deal with stress at a curative and preventive level, extending those skills to the workplace.  相似文献   
888.
Pigeons responded on two keys in each component of a multiple concurrent schedule. In one series of conditions the distribution of reinforcers between keys within one component was varied so as to produce changes in ratios of reinforcer totals for key locations when summed across components. In a second series, reinforcer allocation between components was varied so as to produce changes in ratios of reinforcer totals for components, summed across key locations. In each condition, resistance to change was assessed by presenting response-independent reinforcers during intercomponent blackouts and (for the first series) by extinction of responding on both keys in both components. Resistance to change for response totals within a component was always greater for the component with the larger total reinforcer rate. However, resistance to change for response totals at a key location was not a positive function of total reinforcement for pecking that key; indeed, relative resistance to extinction for the two locations showed a weak negative relation to ratios of reinforcer totals for key location. These results confirm the determination of resistance to change by stimulus—reinforcer contingencies.  相似文献   
889.
The instigative aggression paradigm, in which male and female subjects instructed a female confederate which shock to set for an opponent in a competitive reaction time task, was employed. It was observed that males instigated more aggression than females and that both passive and assertive noncooperation effectively reduced instigative aggression, the assertive form of noncooperation being only slightly less effective. Questionnaire data suggested that females found the passive noncooperator most desirable while males found her least so. Results were discussed in terms of violation of task role and sex role expectations.  相似文献   
890.
Pigeons' keypecks were reinforced with grain on the average of once per minute by schedules that maintained low response rates and by schedules that maintained high response rates. During these schedules, a fixed-duration conditioned stimulus (CS) ranging from 7.5 to 120 sec in duration across conditions terminated with response-independent food. Response rates during the CS were inversely related to CS duration. The rates and the temporal patterns of responding during the shortest CS were similar whether the ongoing schedule maintained high response rates or low response rates. As CS duration increased, the rate and pattern of responding during the CS converged on the rate and pattern of responding maintained by the baseline schedule. These data indicate that changes in responding during stimuli that signal response-independent reinforcement are not homogeneous throughout the CS; that response measures, such as “suppression ratios”, which presume homogeneity may mislead us; and that conditioned suppression and conditioned enhancement may be better talked about in terms of species-specific approach and avoidance than in terms of emotional states.  相似文献   
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