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211.
In this paper, we applied the behavioral-economic concept of unit price to the study of reinforcer magnitude in an attempt to provide a consistent account of the effects of reinforcer magnitude on behavior. Recent research in the experimental analysis of behavior and in behavioral pharmacology suggests that reinforcer magnitude interacts with the schedule of reinforcement to determine response rate and total consumption. The utility of the unit-price concept thus stems from its ability to quantify this interaction as a cost-benefit ratio (i.e., unit price = characteristics of the schedule of reinforcement divided by magnitude of reinforcement). Research employing the unit-price concept has shown that as unit price increases, a positively decelerating function exists for consumption (i.e., a function with an increasingly negative slope, when plotted on log coordinates) and a bitonic function exists for response rate. Based on these findings, the present analysis applied the unit-price concept to those studies of reinforcer magnitude and drug self-administration that examined the effects of reinforcer magnitude on response rate using simple schedules of reinforcement (e.g., fixed-ratio schedule). This resulted in three findings: (a) Reinforcer-magnitude manipulations and schedule manipulations interact in a manner that can be quantified in terms of unit price as benefit and cost factors, respectively; (b) different reinforcer-magnitude manipulations are functionally interchangeable as benefit factors in the unit-price ratio; and (c) these conclusions appear warranted despite the differences in reinforcers (food or drug), species (dogs, monkeys, or rats), and schedules (interval or ratio), and despite the fact that these studies were not designed for a unit-price analysis. In methodological terms, these results provide further evidence that employing the unit-price concept is a parsimonious method for examining the effects of reinforcer magnitude. In theoretical terms, these results suggest that a single process may underlie the effect of combined reinforcer-magnitude and schedule manipulations.  相似文献   
212.
This study investigated the effectiveness of using visual cues to highlight the seams of baseballs to improve the hitting of curveballs. Five undergraduate varsity baseball team candidates served as subjects. Behavior change was assessed through an alternating treatments design involving unmarked balls and two treatment conditions that included baseballs with 1/4-in. and 1/8-in. orange stripes marking the seams of the baseballs. Results indicated that subjects hit a greater percentage of marked than unmarked balls. These results suggest that the addition of visual cues may be a significant and beneficial technique to enhance hitting performance. Further research is suggested regarding the training procedures, effect of feedback, rate of fading cues, generalization to live pitching, and generalization to other types of pitches.  相似文献   
213.
Pigeons performed on discrete-trial, temporally defined schedules in which the food delay (D) was adjusted according to the latency of the key peck (X) and two schedule parameters (t and A). The schedule function was D = A(tX), where D is the experienced delay between a response and a reinforcer. The schedule parameter t is the maximum value below which the present contingencies occur. A is the additional delay to reinforcement for each second the response latency is shorter than the t value. When A = 0 s, the schedule is a continuous reinforcement schedule with immediate reinforcement. When A = 1 s, the schedule is a conjunctive fixed-ratio 1 fixed-time t-s schedule. When A approaches infinity, the schedule becomes a differential reinforcement of long latency schedule. The latencies for subjects with t = 10 s and t = 30 s were observed with the present schedules having seven values for A between 0 s and 11 s. In addition, the latencies for subjects for which t = 30 s were observed at an A value of 31 s to 41 s. As the A value increased, the latencies approached the t value for subjects for which t = 10 s. The latencies for 30-s-t subjects did not approach t, even when the A value was 41 s. The latencies for 10-s-t subjects at 11-s A value were longer than those under yoked conditions having exactly the same delays/interreinforcement intervals. These results demonstrated a continuum of latency related to the schedule continuum (value of A) at a small t value.  相似文献   
214.
Timeout from concurrent schedules.   总被引:1,自引:1,他引:0       下载免费PDF全文
Response-contingent timeouts of equal duration and frequency were added to both alternatives of unequal concurrent schedules of reinforcement. For each of 4 pigeons in Experiment 1, relative response rates generally became less extreme as the frequency of timeout increased. In Experiment 2, relative response rates consistently approached indifference as the duration of timeout was increased. Variation in time allocation was less consistent in both experiments. Absolute response rates did not vary with the timeout contingency in either experiment. In a third experiment, neither measure of choice varied systematically when the duration of a postreinforcement blackout was varied. In contrast to the present results, preference has been shown to vary directly with the parameters of shock delivery in related procedures. The pattern of results in the first two experiments follows that obtained with other manipulations of the overall rate of reinforcement in concurrent schedules. The results of the third experiment suggest that an intertrial interval following reinforcement is not a critical feature of the overall rate of reinforcement.  相似文献   
215.
Four pigeons performed on three types of schedules at short (i.e., 10, 30, or 60 s) interreinforcement intervals: (a) a delay-dependent schedule where interreinforcement interval was held constant (i.e., increases in waiting time decreased food delay), (b) an interreinforcement-interval-dependent schedule where food delay was held constant (i.e., increases in waiting time increased interreinforcement interval), and (c) a both-dependent schedule where increases in waiting time produced increases in interreinforcement interval but decreases in food delay. Waiting times were typically longer under the delay-dependent schedules than under the interreinforcement-interval-dependent schedules. Those under both-dependent schedules for 1 subject were intermediate between those under the other two schedule types, whereas for the other subjects waiting times under the both-dependent procedure were similar either to those under the delay-dependent schedule or to those under the interreinforcement-interval-dependent schedule, depending both on the subject and the interreinforcement interval. These results indicate that neither the interreinforcement interval nor food delay is the primary variable controlling waiting time, but rather that the two interact in a complex manner to determine waiting times.  相似文献   
216.
This paper suggests that medical education be revised to assist in diffusing potential ethical dilemmas that arise during health care provision. A revised medical education would emphasize the role of the humanities in the training of physicians, especially in light of recent critiques of the canonical scientific model in general, and more specifically in the use of that model for medical training and practice.I wish to thank Dr. Mary Ann Cutter and Melissa M. Amaro for their critical suggestions.  相似文献   
217.
It is argued that the manner in which we teach science in the high schools represents an outdated positivistic conception of science. The standard presentation of a year of each of chemistry, biology and physics should be replaced by an integrated science plus history, philosophy, and sociology of science which would take a total of three years to complete. A proper appreciation for the true nature of science is essential to the continued health of the scientific enterprise.  相似文献   
218.
The Nazi Holocaust has had continuing and widely reverberating consequences not only for the Jewish survivors but for the world at large. These consequences are detailed, first through a personal account of an Auschwitz survivor, and then through a discussion of the adaptive measures of concentration camp inmates and the long-term psychiatric and psychological effects on survivors and their families. The Survivor or Concentration Camp Syndrome and its relationship to the Post-Traumatic Stress Disorder is described. Indirect effects of the Holocaust have been manifested in various ways, particularly through various levels of psychologic denial displayed by Holocaust criminals and (at least during the early postwar period) by the German public. The Holocaust has had profound effects on the ways the Jewish people regard themselves and are seen by others. Finally, the Holocaust can be seen as offering a kind of paradigmatic signature to the worldview of the end of the 20th century, emphasizing the persistence of evil and the limitations of the idea of progress.  相似文献   
219.
Psychology has been integral to the field of family medicine since its inception as a medical specialty in the 1960s. Psychologists and other behavioral scientists contribute to family medicine in teaching clinical skills, in defining research questions, in developing research methodology, and in creating integrated physical/mental health care delivery systems. Future developments in the field of psychology in family medicine are likely to emphasize development and evaluation of screening measures which identify mental health problems in primary care, development of early intervention for those mental health problems, and more precise measurement of process and quality of care and health outcomes. Psychologists have an important role to fulfill in educating physicians on alternatives to pharmacologic and medical interventions for common presenting problems in primary care. However, current economic forces shaping the practice of medicine may work against further enhancing the efficacy of the physician in dealing with psychosocial issues. The future role of psychology in family medicine is not yet delineated, and while the move toward parity of reimbursement for mental and physical health care delivery may enhance this collaboration, there is a need to continue to evaluate how the psychological well-being of patients is influenced in the evolution of new models of care delivery.  相似文献   
220.
The future of pediatric psychology is reviewed and placed in brief historical context in relation to children's psychological health care. Contemporary trends affecting the delivery of psychological services, research, and clinical training are highlighted, with suggestions for future development. Pediatric psychology is a child-based, developmentally-focused multidisciplinary practice directed toward psychosocial and neuropsychological issues of health and illness in children and youth. Pediatric psychologists need to develop strong professional identities as health care psychologists combined with a collegial and collaborative arrangement with physicians to ensure the future growth and development of pediatric psychology in the next century as a major vehicle to promote children's health care.  相似文献   
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