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881.
An incentive program to motivate seat belt use was implemented at a large munitions plant. Seat belt usage was assessed daily at an entrance/exit gate of the industrial complex when employees arrived for work in the morning and departed in the afternoon. During treatment incentive fliers, which prompted seat belt usage and gave belt wearers opportunities to win prizes, were distributed only in the afternoon. Seat belt wearing increased from baseline means of 20.4% and 17.3% during the morning and afternoon, respectively, to averages of 55.5% during afternoon departures and 31.1% during morning arrivals. During follow-up, mean belt use dropped almost to baseline levels. Categorizing vehicles according to driver sex and license plate number enabled a study of belt wearing practices of individuals, and revealed that the incentive program influenced some drivers to wear their seat belts during morning arrival when incentives were not distributed (i.e., treatment generalization) and during a follow-up period after the incentives were withdrawn (i.e., response maintenance).  相似文献   
882.
Three adult female elephants (Elephas maximus) were tested on a light-dark discrimination problem with an 8-yr intertrial interval. The first subject took only 6 min to reach criterion and made only two errors, suggesting remarkable retention. The other two subjects were found to have visual anomalies that would have gone undetected without this research.  相似文献   
883.
This study demonstrated the effect of training nine lower socio-economic adults participating as policy board members in a federally funded rural community project to make behaviorally defined statements to increase problem-solving behaviors in board meetings. A multiple-baseline design across subjects and skills was used to analyze the behavioral categories of: (1) stating the problem; (2) finding solutions to the problem, and (3) implementing the action to the solution. Problem-solving responses during board meetings increased for subjects following training and remained higher than baseline during follow-up.  相似文献   
884.
Covariation within behavior repertoires of problem children were examined. Two boys, referred for psychological help, were observed both at school and at home for about 3 yr. A coded observation system permitted scoring of 19 child-behavior categories and six social-environment categories. After a two-month baseline, behavior categories were intercorrelated, demonstrating that each child showed a group of behaviors that covaried. These groupings were specific to the home and school settings. Contingency management procedures were then applied to each child's problem behaviors in one setting. Next, a reversal phase was instituted, followed by resumption of the initial contingency management phase. These three phases lasted seven months, until the end of the children's public school terms. Results showed that the baseline group of covarying behaviors continued to covary over the three experimental phases. The children then entered a remedial education setting for three summer months, and then returned to schools and were observed in follow-up for 2 yr. The baseline group of behaviors continued to covary during both phases. The behavior covariations could not be accounted for on the basis of temporal relationships between the behaviors and social environment categories. Although no behavior covariations extended across either child's home and school settings, contingency management procedures produced across-setting effects.  相似文献   
885.
In two experiments, pigeons' responding was equally reinforced in the presence of four line-orientation stimuli. Responding was then reinforced when only two of the four orientation stimuli were present; the remaining two orientations appeared during extinction. Response rates were often highest in the stimulus adjacent to the orientations presented during extinction and often lowest in that orientation adjacent to the orientations presented with reinforcement. These effects were stronger and more persistent when the stimuli were separated by a smaller angle, rendering the discrimination more difficult. These and other data suggest that discrimination training may not be accurately explained in terms of the simple effects of reinforcement and nonreinforcement associated with isolated stimuli, nor by accounts that depend upon stimulus generalization. Recent accounts of contrast that depend upon “emotionality” produced by nonreinforced responding or upon reinforcement-elicited responses are also difficult to apply to these data.  相似文献   
886.
Pigeons were studied on a three-component multiple schedule where all reinforcement was independent of responding. Two components were cued by different keylights and were associated with different rates of reinforcement. The third was always a no-key period associated with extinction. After a few sessions, pecking was elicited by the keylights signalling the reinforcement and continued to be maintained indefinitely. The duration and sequence of the three components were varied to determine if the primary controlling variable was differences in the overall probability of reinforcement, or if it was the immediate change in reinforcement signalled by the onset and/or offset of the stimulus. Both variables were found to control behavior. When 30-sec components were used, the primary controlling variable was the overall probability of reinforcement, but when 3-min components were used, overall probability had little effect. Control by local changes in reinforcement also occurred, although the type of local control varied both across subjects and experimental conditions. Some behaviors were controlled more by the change in reinforcement signalled by the onset of the stimulus, while others were controlled more by the change signalled by the offset of the stimulus.  相似文献   
887.
Behavioral contrast of time allocation   总被引:3,自引:3,他引:0       下载免费PDF全文
Pigeons' standing on a platform produced food reinforcement according to two-component multiple schedules in which either both components consisted of the same variable-interval schedule or one of these was replaced with a component without reinforcement (extinction). The components of the multiple schedule alternated every 30 sec, and were signalled by changes in the color of diffuse overhead illumination. Changing the schedule of one of the components to extinction increased the percentage of time spent on the platform during the unchanged component (behavioral contrast). This result casts doubt on accounts that attribute behavioral contrast to variations in the rate of noninstrumental elicited responses.  相似文献   
888.
Rats repeatedly acquired the performance of selecting only the four baited arms in an automated eight-arm radial maze, with the arms containing food pellets randomly assigned prior to each session. During each 14-trial (trial: obtain all four pellets) daily session, the number of errors (selecting nonbaited arms or repeating arm selections) showed a within-session decline, and choice accuracy for the first four arm selections showed a positive acceleration across trials for all rats. An index-of-curvature statistic, calculated for total errors, was used to quantify both the within- and between-session improvement of performance. Scopolamine (0.03 to 0.3 mg/kg, ip), but not methylscopolamine (0.3 mg/kg), reduced the accuracy of the first four selections of each trial and increased total within-session errors for all rats. Session times also were increased by scopolamine. An examination of within-session accuracy showed only slight signs of improvement at the higher dosages of scopolamine. The results indicate that behavior in transition states maintained by reinforcement contingencies in the radial maze is similar to that maintained by extended chained schedules, despite the fact that some of the stimuli controlling behavior in the maze are absent at the moment behavior is emitted.  相似文献   
889.
The Holte Sleeping Technique is an alternative to medication to facilitate sleep onset in situations of normal stress. The technique is based on a combination of conditioning within the theory of learning, simulation of natural bodily processes, and manipulation of naturally available sleep-releasing stimuli. The author describes the technique and reports on experimental testing of its efficacy. Fifty-six female subjects were selected according to criteria based on questionnaires and sleep logs. The subjects were randomly assigned to a treatment group, a placebo group, and a no-treatment group. A pre-test-post-test design was used. The author questions the generalizability of findings from modern electronic sleep laboratories to the bedrooms of everyday life. In order to optimize the combination of normal stress, objective criteria and generalizability, sleep onset was measured by behavioural criteria based on the "fog-horn procedure" developed by the author. At post-test 67% of the treatment group fell asleep, while only 17% of the placebo group and 25% of the no-treatment group fell asleep. The differences were significant. It is concluded that the Holte Sleeping Technique is highly effective. In a discussion of placebo trials the author argues that traditional medical trials do not take into consideration the differentiating psychological attribution effects occurring by giving the same experimental instruction under different experimental conditions. As a consequence the active treatment is given better conditions than the placebo in traditional clinical trials.  相似文献   
890.
Pigeons pecked two keys in a probability matching situation in which four two-peck sequences were intermittently reinforced: left-left, left-right, right-left and right-right. In Phase 1, relative reinforcement rate was varied with respect to the first response of a sequence: reinforcers were differentially assigned for left-left and left-right sequences as opposed to right-left and right-right sequences. The second response of reinforced sequences occurred equally on the left and right keys across conditions. In Phase II, relative reinforcement rate was varied for sequences that involve an alternation as opposed to those that did not. The relative outputs of the different sequences matched the relative reinforcement rates for the different sequences in both phases. Relative response rates for key pecks did not always match relative reinforcement rates. The intertrial interval separating responses was varied in both phases; increases in the intertrial interval affected the relative frequency of different sequences. The results demonstrate that response sequences acted as functional units influencing choice and thus support a structural account of choice. At the same time, the matching of relative sequence proportion and relative reinforcement rate supports a matching account.  相似文献   
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