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871.
872.
The relationship between reinforcer amount and daytime smoking reduction in smokers offered money for reduced afternoon breath carbon monoxide (CO) levels was examined. Twenty-three hired regular smokers with average baseline CO levels of about 30 ppm were exposed in random order to five sliding scale payment schedules that changed daily or weekly. Money was available for afternoon CO readings between 0 and 21 ppm with pay amount inversely related to the absolute CO reading obtained. Maximum pay amount for readings below 7 ppm varied among $0, $1.50, $3, $6, and $12 per day. Contingent reinforcement promoted CO and daytime cigarette reduction within individuals with the amount of behavior change related to the amount of payment available. Average CO levels decreased from 30 to 15 ppm as a function of pay amount whereas self-reported daytime cigarettes decreased from 12 to 5 per day. Average minutes of cigarette abstinence prior to the afternoon study contact increased from 62 to 319 minutes as a function of pay amount, whereas the percentage of available money earned increased from 22% to 48%. Nontargeted evening cigarette use also decreased during periods of daytime smoking reduction. The orderly effects of this contingent reinforcement intervention on daytime smoking of regular smoker volunteers suggest that this is a sensitive model for continued evaluation of factors that influence smoking reduction and cessation. 相似文献
873.
James M. Malott Russell E. Glasgow H. Katherine O'Neill Robert C. Klesges 《Journal of applied behavior analysis》1984,17(4):485-495
We evaluated the effects of adding a social support component to a worksite controlled smoking treatment program. Twenty-four participants were randomly assigned to either a controlled smoking or a controlled smoking plus partner support condition. Within a multiple baseline across behaviors design, smokers in both conditions made efforts to achieve sequential 50% reductions in: (a) nicotine content of brand smoked, (b) number of cigarettes smoked per day, and (c) percentage of each cigarette smoked. Self-monitoring records, laboratory analyses of spent cigarette butts, and carbon monoxide determinations indicated that both conditions were effective in producing significant reductions in each of the three target behaviors and in carbon monoxide levels. All participants who quit smoking during the program maintained their abstinence at a 6-month follow-up, and those who did not quit were smoking less at follow-up than they had at pretest on all dependent variables. However, few differences were observed between controlled smoking and controlled smoking plus partner support conditions either during treatment or at the 6-month follow-up. Results are discussed with regard to previous worksite studies, future directions for research on social support, and variables that may have mediated treatment outcome. 相似文献
874.
Y. Haruki T. Shigehisa K. Nedate M. Wajima R. Ogawa 《International journal of psychology》1984,19(1-4):527-545
Effects of new types of reinforcement, alien type and alien combined with external type (double reinforcement), were examined in comparison with a conventional external one. One hundred and twenty children, 6th grade boys and girls, worked on learning discrimination tasks. Under alien reinforcement, upon correct responses of the child the experimenter received reinforcers from him-(or her-) self thus reinforcing the child responses. Under each condition, alien, external or double, children learned the tasks and their learning efficacy increased. Personality characteristics of children, in terms of extraversion and emotionality, differentiated effects of three reinforcement conditions on learning behavior and efficacy. The effect of alien reinforcement was influenced by the personality factors most, and that of double reinforcement least. In addition, personality factors influenced differently between alien and external conditions. Learning occurred differently under three different conditions of reinforcement, depending on the personality type of learners. Underlying mechanisms of alien reinforcement were different from, and its functions were independent of, those of external reinforcement. None of the effects of alien reinforcement on learning and motivation were contaminated by the intellectual faculties of learners. 相似文献
875.
We investigated the programming of generalization and maintenance of correspondence between verbal and nonverbal behavior in a preschool setting. Four children participated in a series of multiple-baseline designs. In Experiment 1, delayed reinforcement of verbal behavior effectively controlled maintenance of correspondence with previously trained responses and also resulted in generalization of correspondence to one untrained response. As the latter effect was limited, Experiment 2 was a further assessment of the effects of delayed reinforcement of generalization of correspondence to untrained responses, and consistent generalization was shown. Experiment 2 also showed that generalization, if lost, could be recovered through use of "booster training," in which the original contingencies were reinstated for a brief period. Experiment 3 provided replications, with two additional children, of the effects of delayed reinforcement on maintenance of correspondence. Results are discussed in terms of using delayed reinforcement as an indiscriminable contingency. 相似文献
876.
Bennett I. Bertenthal Dennis R. Proffitt James E. Cutting 《Journal of experimental child psychology》1984,37(2):213-230
Two experiments assessed infant sensitivity to figural coherence in point-light displays moving as if attached to the major joints of a walking person. Experiment 1 tested whether 3- and 5-month-old infants could discriminate between upright and inverted versions of the walker in both moving and static displays. Using an infant-control habituation paradigm, it was found that both ages discriminated the moving but not the static displays. Experiment 2 was designed to clarify whether or not structural invariants were extracted from these displays. The results revealed that (1) moving point-light displays with equivalent motions but different topographic relations were discriminated while (2) static versions were not, and (3) arrays that varied in the amount of motion present in different portions of the display were also not discriminated. These results are interpreted as indicating that young infants are sensitive to figural coherence in displays of biomechanical motion. 相似文献
877.
Barbara A. Morrongiello Rick C. Robson Catherine T. Best Rachel K. Clifton 《Journal of experimental child psychology》1984,37(2):231-250
Five-year-old children were tested for perceptual trading relations between a temporal cue (silence duration) and a spectral cue (F1 onset frequency) for the “say-stay” distinction. Identification functions were obtained for two synthetic “say-stay” continua, each containing systematic variations in the amount of silence following the /s/ noise. In one continuum, the vocalic portion had a lower F1 onset than in the other continuum. Children showed a smaller trading relation than has been found with adults. They did not differ from adults, however, in their perception of an “ay-day” continuum formed by varying F1 onset frequency only. The results of a discrimination task in which the two acoustic cues were made to “cooperate” or “conflict” phonetically supported the notion of perceptual equivalence of the temporal and spectral cues along a single phonetic dimension. The results indicate that young children, like adults, perceptually integrate multiple cues to a speech contrast in a phonetically relevant manner, but that they may not give the same perceptual weights to the various cues as do adults. 相似文献
878.
Carl E Granrud Albert Yonas Linda Pettersen 《Journal of experimental child psychology》1984,38(1):19-32
Monocular depth perception was compared with binocular depth perception in 5- and 7-month-old infants. Reaching was used as the dependent measure. Two objects, identical except in size, were presented simultaneously to each infant. The smaller object was within reach for the infants while the larger object was just beyond reach. The two objects subtended equal visual angles from the infants' observation point. With binocular presentation, 96% of the 7-month-olds' reaches and 89% of the 5-month-olds' reaches were for the nearer object. With monocular presentation, 58% of the 7-month-olds' reaches and 65% of the 5-month-olds' reaches were for the nearer object. The reaching preferences observed in the monocular condition indicated sensitivity to monocular depth information (motion parallax, accommodation, and relative size information were available). Binocular viewing, however, resulted in a far more consistent tendency to reach for the nearer object. This result suggests that the infants' perception of the objects' distances was more veridical in the binocular condition than in the monocular condition. 相似文献
879.
This research had two aims. The first was to test three explanations of performance on N-term series tasks by young children: the labeling model of B.DeBoysson-Bardies and K. O'Regan (1973), Nature (London), 246, 531–534, the sequential-contiguity model of L. Breslow (1981, Psychological Bulletin, 89, 325–351), and the ordered array or image model of C. A. Riley and T. Trabasso (1974, Journal of Experimental Child Psychology, 17, 187–202). In the first experiment, 5-year-old children were taught additional premises which would interfere with labeling and sequential-contiguity processes, but not with forming an ordered array. Reasoning performance was essentially comparable to previous results with the paradigm, thus supporting the ordered array model. The second aim was to reexamine children's ability to learn sets of premises which can be assembled into an ordered array, since there was reason to believe that previous studies had created false positives. In the second experiment, 3- to 7-year-old children were taught either overlapping (a > b, b > c, …) or nonoverlapping (a > b, c > d, …) premises. Overlapping premises can be integrated into an ordered array (a, b, c, d, e), but nonoverlapping premises cannot. However, the overlapping condition proved more difficult, and the success rate for preschoolers () was of zero order. This raises doubts about their ability to learn a set of premises of the kind required for transitive inference. These doubts were strengthened by the third experiment which showed that when premises were not presented in serial order, preschool () children could not learn the premises of an N-term series task. 相似文献
880.
In three experiments, the effect of additional "contextual" elements on the discrimination of the orientation of linear and curvilinear segments was investigated with 4-month-old infants. In Experiment 1, paired visual matrices (one which contained some irregularity in orientation of internal elements, vs one which contained no irregularities) were presented. Infants detected irregular matrices significantly better than chance, but such detection was not aided by contextual elements. Discrimination of orientation in Experiment 2 was assessed with a paired-comparison familiarization-novelty paradigm. It was found that the addition of elements here significantly aided discrimination of linear segment orientation, but not curvilinear segment orientation. Experiment 3 investigated why this effect was not found for curvilinear segments; after equating the curvilinear stimuli to linear ones used in Experiment 2 with respect to the closedness of figure, discrimination of curvilinear orientation was observed. 相似文献