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Tolerance to and residual effects of cocaine in squirrel monkeys depend on reinforcement-schedule parameter. 总被引:7,自引:6,他引:1 下载免费PDF全文
Lever pressing by 4 squirrel monkeys was maintained under a three-component multiple fixed-ratio schedule of food presentation; components differed with respect to ratio size. For each monkey, acute administration of cocaine (0.03 to 1.3 mg/kg, i.m.) produced dose-dependent decreases in overall response rate in each component. During repeated daily administration of 1.0 mg/kg of cocaine, tolerance developed to the rate-decreasing effects under each of the ratio contingencies, but developed to a greater extent and was evident in earlier parts of sessions for performance under the smaller ratios. Response rates of 2 monkeys increased above nondrug control levels despite the putative reinforcer not being consumed during the session. When saline or a smaller dose of cocaine was substituted for 1.0 mg/kg, response rates often were suppressed below nondrug control-level responding. This suppressive effect was observed in each monkey and was more likely to be observed and/or to be of greater magnitude in large-ratio components for 3 of the 4 monkeys. When saline was administered chronically at the end of the chronic-drug phase, response rates remained suppressed in the large-ratio component for 2 of the monkeys. There was, therefore, a schedule-dependent dissociation between behavioral tolerance and the residual effects: Tolerance was greater when small ratios were arranged, whereas the residual effects were more pronounced when larger ratios were arranged. 相似文献
74.
Behavioral economics of drug self-administration. II. A unit-price analysis of cigarette smoking. 总被引:4,自引:4,他引:0 下载免费PDF全文
W K Bickel R J DeGrandpre J R Hughes S T Higgins 《Journal of the experimental analysis of behavior》1991,55(2):145-154
In behavioral economics, the ratio of response requirement to reinforcer magnitude is referred to as unit price. Previous research with nonhuman subjects has demonstrated that (a) comparable amounts of food are consumed at the same unit price even though different response requirements and reinforcer magnitudes comprise that unit price and (b) increases in unit price decrease food consumption in a positively decelerating fashion. The present study assessed the generality of these findings to the cigarette smoking of 5 human volunteers. During approximately 18 3-hr sessions, various combinations of response requirement (fixed-ratio 200, 400, and 1,600) and reinforcer magnitude (1, 2, and 4 puffs per bout) were arranged. Consumption (i.e., the number of puffs) generally was comparable at the same unit price independent of the response requirement and reinforcer magnitude comprising that unit price. In addition, increasing unit price generally decreased consumption in a positively decelerating fashion. These results extend the generality of the unit-price analysis to human cigarette smoking. Moreover, these results further support the position that reinforcer magnitude and response requirement are functionally equivalent and interact to determine consumption. The concept of unit price, by integrating and summarizing the effects of those two operations, provides a more parsimonious explanation of the results than do separate evaluations of the effects of response requirement and reinforcer magnitude. 相似文献
75.
The present investigation focused upon the impact of gender and various powerful and less powerful linguistic features on the communication of unfamiliar male and female college students. Same-sex and mixed-sex dyads were recorded as they engaged in discussions regarding suggestions for a bogus freshman orientation booklet. Although few gender differences were found, the result of a factor analysis yielded three factors: questions, suggestions, and process variables. These factors are consistent with a power perspective in the use of various linguistic features. However, the present findings suggest that gender and power alone cannot explain differences in communication styles. Rather, the results suggest the need to consider other aspects of the speaker to explain differences that occur in the use of language. 相似文献
76.
Robert Fendrich Howard C. Hughes Patricia A. Reuter-Lorenz 《Attention, perception & psychophysics》1991,50(4):383-387
If an observer’s fixation point is extinguished just prior to the onset of a peripheral target, the latency to saccade to that target is reduced. We show that this "gap effect" is not specific to visual targets. Observers made saccades to a light flash or to a white-noise burst. A warning tone was presented on every trial to control for the possible warning effect of the fixation-point offset. For both target modalities, saccade latencies were significantly reduced when the fixation point was extinguished 200 msec prior to the target onset. Implications of this outcome for interpretations of the gap effect are considered. It is argued that the presence of a gap effect for tones, in conjunction with previous findings, is consistent with the hypothesis that the gap effect is produced by a facilitation of premotor processes in the superior colliculus. 相似文献
77.
It is postulated that adult vocational maturity needs to be assessed because of the changing developmental tasks encountered during the course of a career. Vocational maturity having been found to be multidimensional, existing undimensional inventories of adult vocational maturity are considered of limited although demonstrated validity. Relevant theories of adult vocational development and adjustment are reviewed. Super's proposed adult vocational maturity model is examined for the promise that it offers and for the problems that arise in developing a multidimensional measure of vocational maturity. A way of surmounting these problems is proposed as a basis for work now being undertaken. 相似文献
78.
Matthew M. Burg Dennis H. Reid Jennifer Lattimore 《Journal of applied behavior analysis》1979,12(3):363-375
The use of a self-recording and supervision program to increase interactions between direct care staff and profoundly retarded persons in a state residential facility was investigated. Following baseline, staff were provided with instructions regarding what to self-record, criteria for how many interactions to record, and a prepared card on which to make the recordings. Throughout the study, the staff supervisor monitored intermittently staff-client interactions. Observations indicated that when the staff recorded their interactions with clients in a loosely structured dayroom setting, the rate of interactions increased noticeably for each staff person. Behavioral ecology measures indicated that other staff responsibilities, such as maintaining the cleanliness of residents and the physical area, were not affected detrimentally when social interactions increased and actually showed small improvements. Additionally, small decreases in resident self-stimulatory and disruptive/aggressive behaviors occurred when the rate of social interactions from staff persons increased. Follow-up measures indicated that the rate of staff self-recording was variable, but when staff did self-record, the increased rate of staff-client interactions maintained. 相似文献
79.
The effects of EMG biofeedback training on cursive handwriting were investigated for 4 girls and 5 boys in Grade 4. A significant reduction in EMG between the first baseline session and the last training session was obtained. Four of 5 characteristics of handwriting improved significantly. The need for carefully designed research comparing EMG biofeedback training and relaxation training was indicated. A self-control factor in handwriting was hypothesized. 相似文献
80.