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11.
The effects on aggressive behavior, open-field activity, and pain threshold of bilateral microinjections of serotonin (20 micrograms) and quipazine (20 micrograms), the direct serotonergic receptor agonist, into the cortico-medial amygdala were investigated in Wistar rats. Both drugs significantly prolonged the attack latency in isolated killer rats (predatory aggression model), and suppressed the incidence of aggressive postures/attacks in shock-induced fighting test (affective aggression). The only difference in the open-field behavior was the lower number of central square entries in drug-treated compared to saline-injected rats. None of the substances produced any significant change in jump threshold. It is concluded that stimulation of serotonin receptors within the amygdala produces inhibition of affective and muricidal behavior in isolated rats. The effect does not seem to be dependent on changes in general activity and pain sensitivity.  相似文献   
12.
The study of any problem involving waiting situations invariably assumes that people dislike having to wait. The analysis of queueing problems usually prescribes that some costs should be associated with the time people spend waiting to be served. These are usually considered to be of an economic nature, though the existence of other costs of a psychological nature is accepted. It is generally accepted that after having to wait for a certain amount of time, anxiety and stress start to build up in an individual, due both to the sense of waste and the uncertainty involved in a waiting situation. This work provides a theoretical basis for analysing this building up process as it occurs during the waiting period. It is proved that, under very general conditions, the resulting psychological stress accumulated during the process is a marginal increasing function of the waiting time, and some strategies to minimise it are developed. The results obtained give theoretical support to the usual assumptions underlying the development of systems to provide “real time” information to people in waiting situations. This is especially important in the operation of public transportation systems. The results also provide theoretical support to the “convex” treatment usually given to the waiting cost function in queueing problems.  相似文献   
13.
The emphasis of much of the existing research on social support-health relationships has been on the availability and impact of support on the recipient, but social psychologists have paid little attention to the costs to the caregiver of providing that support. In an earlier study (Schulz & Decker, 1985), we found that the long-term coping of individuals experiencing chronic disability as a result of spinal-cord injury was facilitated by the availability of a primary support person, or caregiver. In this study we examined the determinants of well-being of the primary caregiver of the middle-aged and elderly spinal-cord-injured persons. Psychological well-being, life satisfaction, and depression were the dependent measures. The availability of social support, social contact, and feelings of control over one's life were important determinants of caregiver well-being, even after controlling for health and income. In addition, the amount of time spent each day assisting the disabled person was a strong independent correlate of depression, and the extent to which the caregiver felt burdened by the victim was significantly and negatively related to life satisfaction. These results are discussed in the context of a comprehensive stress-coping model. Since data were available from both disabled individuals and their primary support persons, we had the unique opportunity to compare the perspectives of both those giving and receiving daily care. We found no relationship in levels of psychological well-being and depression reported by the disabled person and caregiver; however, caregivers attributed to the victims affective levels similar to their own.  相似文献   
14.
Dan Lloyd 《Synthese》1987,70(1):23-78
Commonsense psychology and cognitive science both regularly assume the existence of representational states. I propose a naturalistic theory of representation sufficient to meet the pretheoretical constraints of a folk theory of representation, constraints including the capacities for accuracy and inaccuracy, selectivity of proper objects of representation, perspective, articulation, and efficacy or content-determined functionality. The proposed model states that a representing device is a device which changes state when information is received over multiple information channels originating at a single source. The changed state of a representing device is a representation. The unitary information source which would give rise to the information impinging on the representing device, and hence, give rise to the representation, is the content of the representation. The model meets the pretheoretic constraints, and also conforms to available neurobiological data for two invertebrate species.  相似文献   
15.
Some features of social living were investigated in three inbred strains of mice: C57Bl/6j, Balb/cj, and NIH. Five social behaviors--Aggression, Submission, Allogrooming, Social Rest and Rest Alone, as well as Wheel Running Activity--were recorded 2 h daily for a week, in 26 groups of seven male mice living in an enriched environment. Dominants and subordinates among strains shared some behavioral characteristics, but strain contributions upon social structure were also detected. Similarities among strains included the appearance of a single dominant mouse per group rated as the most aggressive, besides from being the animal presented with most Submissions. Allogrooming was more frequent among subordinates than among dominants and subordinates. Differences among strains were that agonistic behavior among subordinates was higher in the Balb/cj and NIH groups than in the C57Bl/6j mice. NIH mice were recorded in Rest Alone more often than mice from the other strains. C57Bl/6j dominants showed higher rates of Wheel Running Activity than subordinates.  相似文献   
16.
In this paper, we present a BASIC program for Apple II series computers that allows the user to obtain perspective drawings of two-dimensional functions of known analytical expression. Also, we outline a procedure for obtaining perspective representations of two-dimensional arrays of data using the same program. The program should run on any computer with graphics mode with only slight modifications in the graphics commands.  相似文献   
17.
The influence of the length of time elapsing between the termination of an interval on its estimated duration was tested in three experiments. In the first experiment, 89 subjects performed the W, C, and CW tasks of the Stroop color-word test. The duration of each of these three tasks, which was 10 second in reality, was estimated twice by every subject. Once, immediately upon completion of the task (IE), and a second time 90 seconds later (RE), both under prospective paradigm. The nature of the relationship between task difficulty and its estimated duration was found to be different in IE and RE. A negative relationship was found in IE while in RE no significant difference was found between difficulty levels. In the second experiment it was found that RE's trend was not caused by estimation order. In the third experiment IE and RE were tested under prospective and retrospective paradigms. In the perspective paradigm the results obtained in experiment 2 were replicated. In the retrospective paradigm the relationship between task difficulty and time estimation was, unlike the prospective paradigm, negative in both IE and RE. The significance of the results to time estimation theory was discussed.  相似文献   
18.
COVID-19 pandemic led to introduction of lockdown measures in many countries, while in Serbia the Government also introduced the curfew by which vulnerable groups of citizens were prohibited from leaving their homes at any time. In such a situation many citizens organized to voluntarily offer their help to those in isolation, which offered a unique opportunity to examine prosocial behavior in the natural setting of global crisis. This study examined the differences between non-helpers and helpers, as well as groups of helpers who provided their help to close or unknown others, in personality (prosocial tendencies, selfishness and communal narcissism) and context-related factors (situation specific empathy and fear) of prosocial behaviors. Additionally, the study also analyzed the helping-related affect among helpers, depending on the recipient of help and personality characteristics. Results revealed that groups of helpers with different recipients of help (close persons, unknown persons or both) were not different among each other, but they were different from non-helpers. Non-helpers were more selfish and had self-focused prosocial tendencies, and they showed less empathy towards people in isolation, compared to helper groups. However, the helping-related affect depended on the recipient of help and helper's personality traits. This study confirmed some previous findings and offered novel insights into factors related to helping in crises.  相似文献   
19.
20.
This review involved a systematic analysis of equivalence-based instruction (EBI) that aimed to improve food-size interventions in diverse populations. Systematic searches identified seven studies published since 2010 that met inclusion criteria. These studies were analyzed according to their participants, design, setting, content taught, training structures, training protocol, testing format, treatment integrity, and outcomes. Results showed EBI procedures for teaching food estimation skills have been mostly implemented with adults. The type of content taught in the identified studies included carbohydrate ranges, portion size with food and non-food items, measuring cups and nutritional content of calories. Majority of included studies used one-to-many training structure and simultaneous protocols for teaching stimulus relations. Five studies completed a generalization probe and three studies reported treatment integrity data. Overall, all participants demonstrated skill acquisition of novel relations between food and portion measurement aides. Recommendations for future research and clinical applications of EBI in teaching food portion estimation are presented.  相似文献   
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