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941.
Hoarding behavior, patterns of use of possessions, and emotional attachment to possessions were examined among a sample of female undergraduates and a sample of community volunteers. Hoarding behavior was associated with a decreased frequency of use of possessions and excessive concern about maintaining control over possessions. Furthermore, high scores on the hoarding scale were associated with higher levels of perceived responsibility for: (1) being prepared; and (2) the well-being of the possession. Hoarding was also associated with greater emotional attachment to possessions and to the reliance on possessions for emotional comfort. The implications of these findings for the definition of hoarding are discussed.  相似文献   
942.
943.
Recent legislative and regulatory developments have focused attention on older adults' capacity for involvement in health care decision-making. The Omnibus Budget Reconciliation Act of 1987 (OBRA 87) focused attention on the rights of nursing home residents to be involved in health care decision-making to the fullest extent possible. This article uses data from the 1987 National Medical Expenditure Survey (NMES) to examine rates of incapacity for health care decision-making among nursing home residents. Elements of the Oklahoma statute were used to operationalize decision-making incapacity: disability or disorder, difficulty in decision-making or communicating decisions, and functional disability. Fifty-three percent of nursing home residents had a combination of either physical or mental impairment and an impairment in either self-care or money management. The discussion focuses on the policy and practice implications of significant rates of incapacity among nursing home residents.  相似文献   
944.
The efficacy of Cognitive Behaviour Therapy (CBT) in the treatment of depression is now established. However, explanations for the efficacy of CBT are mixed. The evidence needed to support the explanation advanced by cognitive theory is lacking. This paper critically reviews the available empirical evidence. Forty-four outcome or process studies of therapy with depression are reviewed and 21 of these are subjected to a meta-analysis to investigate the relationship between change in cognitions and change in level of depression during different kinds of therapy. Our analysis shows that: (1) change in cognitive style occurs in all four categories of treatment: CBT, Drug Therapy, Other-Psychological Therapy, and Waiting List; (2) there was a significant difference between Waiting List and all the active treatments in change in cognitions, but not between active treatments; (3) the degree of change in cognitive style is significantly related to change in depression as measured by the Beck Depression Inventory (BDI), but not the Hamilton Rating Scale for Depression (HRS-D); and (4) the relationship between cognitive change and depression is not unique to CBT. Our findings show that CBT does provide some support for the cognitive models of depression but the relationship between cognitive change and recovery from depression is not unique to CBT.  相似文献   
945.
Four pigeons responded on multiple schedules arranged on a “main” key in a two-key experimental chamber. A constant schedule component was alternated with another component that was varied over conditions. On an extra response key, conjoint schedules of reinforcement that operated in both components were arranged concurrently with the multiple schedule on the main key. On the main key, changes in reinforcement rate in the varied component were inversely related to changes in response rates in the constant component (behavioral contrast). On the extra key, some reinforcers were reallocated between components, depending on the schedules in effect on the main key in the varied component. In the varied component, the obtained rates of reinforcement on the extra key were inversely related to main-key reinforcement rate. In the constant component, extra-key reinforcer rates were positively related to main-key reinforcer rates obtained in the varied component, and were not a function of response rates on the extra key. In two comparisons, the rate at which components alternated and the value of the main-key schedule in the constant component were varied. Consistent with earlier work, long components reduced the extent of contrast. Reductions in contrast as a function of component duration were accompanied by similar reductions in the extent of reinforcer reallocation on the extra key. In the second comparison, lowering the rate of reinforcement in the constant component increased the rate at which extra-key reinforcers were obtained, reduced the extent of reinforcer reallocation, and reduced contrast. Overall, the results are consistent with the suggestion that some contrast effects are due to the changes in extraneous reinforcement during the constant component, and that manipulations of component duration, and manipulations of the rate of reinforcement in the constant component, affect contrast because they influence the extent of extraneous reinforcer real-location.  相似文献   
946.
Behavioral momentum theory relates resistance to change of responding in a multiple-schedule component to the total reinforcement obtained in that component, regardless of how the reinforcers are produced. Four pigeons responded in a series of multiple-schedule conditions in which a variable-interval 40-s schedule arranged reinforcers for pecking in one component and a variable-interval 360-s schedule arranged them in the other. In addition, responses on a second key were reinforced according to variable-interval schedules that were equal in the two components. In different parts of the experiment, responding was disrupted by changing the rate of reinforcement on the second key or by delivering response-independent food during a blackout separating the two components. Consistent with momentum theory, responding on the first key in Part 1 changed more in the component with the lower reinforcement total when it was disrupted by changes in the rate of reinforcement on the second key. However, responding on the second key changed more in the component with the higher reinforcement total. In Parts 2 and 3, responding was disrupted with free food presented during intercomponent blackouts, with extinction (Part 2) or variable-interval 80-s reinforcement (Part 3) arranged on the second key. Here, resistance to change was greater for the component with greater overall reinforcement. Failures of momentum theory to predict short-term differences in resistance to change occurred with disruptors that caused greater change between steady states for the richer component. Consistency of effects across disruptors may yet be found if short-term effects of disruptors are assessed relative to the extent of change observed after prolonged exposure.  相似文献   
947.
Rats were trained on concurrent schedules under which responses on one lever postponed shock (avoidance) and responses on the other lever produced brief (2-min) periods of signaled timeout from avoidance. For 6 rats, timeout from avoidance was programmed on a variable-interval 45-s schedule that generally resulted in rates that were lower than those on the avoidance lever. For another 6 rats, timeout was arranged on a variable-ratio 15 schedule that produced higher baseline rates. Cocaine (3 to 40 mg/kg) produced large, dose-dependent increases in behavior maintained by timeout in both groups of rats. Avoidance responding was also generally increased by cocaine, but the increases were of lesser magnitude. Increases in response rates were seen across a broad range of doses on behavior maintained by either interval or ratio schedules, an outcome that was unexpected on the basis of most studies of cocaine on food-maintained behavior. These results were similar to those of previous studies of the effects of amphetamine on behavior maintained by timeout from avoidance and suggest that stimulant drugs affect behavior maintained under a shock-postponement schedule differently than they affect behavior maintained by timeout from avoidance.  相似文献   
948.
For years articles have decried the lack of empathy in physicians' relationships with patients. In addition to being empathetic, physicians are called upon to assume the posture of value neutrality, i.e., not imposing one's values when dealing with patients. Empathy is clearly an expression of deeply held values; even the language used to define it is value-laden. Physicians are consistently called upon to exhibit traits which are expressions of their underlying values. However, if proponents of value-neutrality are to be taken literally one must not impose any of one's values on one's patients. But then one wonders how empathy could ever be expressed; further, it is hard to imagine what a truly value neutral physician would be like. It is time we recognize that any relationship between two persons requires the expression of values from both parties. These values help shape that relationship and define its further history. Physicians are not excluded from this process just because they consider themselves professionals. Divulging personal values to patients is both more honest and more in keeping with the concepts of justice, beneficence, non maleficence, and autonomy than to feign value-neutrality. A presentation of some type statement of values is timely and would give patients an idea of where a physician stands on a myriad of issues. Rather than being value-neutral, value non-neutrality seems a more right and reasonable posture for physicians to assume.  相似文献   
949.
What Do We Know When We Know a Person?   总被引:12,自引:1,他引:11  
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950.
The control of the ground reaction force vector relative to the center of gravity (CoG) was examined while subjects performed a back-lifting task. Six male subjects (aged 24.0 +/- 2.5 years) repeatedly lifted a barbell. A biomechanical analysis that used a linked segment model revealed that the summed rotations of body segments during lifting yielded a specific rate of change of the angular momentum of the entire body. This equaled the external moment provided by Fsubg; relative to CoG. This implies that multisegment movements involve control of the angular momentum of the entire body through an appropriately directed Fsubg;. Thus, in dynamic tasks Fsubg; is pointed away from rather than lined up with the CoG, as is the case in static tasks.  相似文献   
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