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The role of the response-reinforcer relation in maintaining operant behavior under conditions of delayed reinforcement was investigated by using a two-operandum (i.e., two-key) procedure with pigeons. Responding on one key was reinforced under a tandem variable-interval differential-reinforcement-of-other-behavior (tandem VI DRO) schedule. The schedule defined a resetting unsignaled delay-of-reinforcement procedure in that a response was required when the interfood interval of the VI schedule lapsed, but further responding during the DRO component on either key reset the time interval. This ensured a fixed delay duration between any response and reinforcement. Responding on another key, physically identical to the first one except for spatial location, otherwise was without consequence. The location of the key correlated with the delay-of-reinforcement procedure varied between sessions according to a semirandom sequence. Differences in response rates between the two keys were greater, with proportionally higher rates on the key correlated with the delay-of-reinforcement procedure, the longer the delay-of-reinforcement procedure remained correlated with the same key. Differences in responding on the two keys also increased within individual sessions. These results suggest that the response-reinforcer relation is the primary determinant of responding when responding is acquired and maintained with delayed reinforcement. 相似文献
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Young Deceivers: Executive Functioning and Antisocial Lie‐telling in Preschool Aged Children 下载免费PDF全文
Shanna Williams Karissa Leduc Angela Crossman Victoria Talwar 《Infant and child development》2017,26(1)
The present study examined the emergence of antisocial lie‐telling in very young children. Lie‐telling was studied in relation to executive functioning skills and children's abilities to identify both truths and lies. A total of 65 children (Mage in months = 31.75, SD = 1.87) participated in a modified temptation resistance paradigm (TRP; designed to elicit spontaneous lies). Executive functioning was measured through an inhibitory control task and a forward search planning task. The Truth/Lie Identification task was administered (Lyon, Carrick, & Quas, 2010 ) to measure children's abilities to accurately distinguish truths and lies. During the TRP, a total of 89.23% children peeked at the toy when a research assistant left the room, and of those children, 29.31% lied to the research assistant. Significant differences on executive functioning measures were found between lie‐tellers and confessors, as well as for the Truth/Lie Identification task. Lie‐tellers had higher scores on measures of inhibitory control and forward search planning. Lie‐tellers also had higher accuracy on the Truth/Lie Identification task than confessors. This study provides a unique contribution to the literature by examining 2.5‐year‐old children's emerging lie‐telling abilities, a relatively understudied age during which fledgling lie‐telling emerges. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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Baron-Cohen S Ring H Chitnis X Wheelwright S Gregory L Williams S Brammer M Bullmore E 《Brain and cognition》2006,61(1):122-130
BACKGROUND: People with autism or Asperger Syndrome (AS) show altered patterns of brain activity during visual search and emotion recognition tasks. Autism and AS are genetic conditions and parents may show the 'broader autism phenotype.' AIMS: (1) To test if parents of children with AS show atypical brain activity during a visual search and an empathy task; (2) to test for sex differences during these tasks at the neural level; (3) to test if parents of children with autism are hyper-masculinized, as might be predicted by the 'extreme male brain' theory. METHOD: We used fMRI during a visual search task (the Embedded Figures Test (EFT)) and an emotion recognition test (the 'Reading the Mind in the Eyes' (or Eyes) test). SAMPLE: Twelve parents of children with AS, vs. 12 sex-matched controls. DESIGN: Factorial analysis was used to map main effects of sex, group (parents vs. controls), and sexxgroup interaction on brain function. An ordinal ANOVA also tested for regions of brain activity where females>males>fathers=mothers, to test for parental hyper-masculinization. RESULTS ON EFT TASK: Female controls showed more activity in extrastriate cortex than male controls, and both mothers and fathers showed even less activity in this area than sex-matched controls. There were no differences in group activation between mothers and fathers of children with AS. The ordinal ANOVA identified two specific regions in visual cortex (right and left, respectively) that showed the pattern Females>Males>Fathers=Mothers, both in BA 19. RESULTS ON EYES TASK: Male controls showed more activity in the left inferior frontal gyrus than female controls, and both mothers and fathers showed even more activity in this area compared to sex-matched controls. Female controls showed greater bilateral inferior frontal activation than males. This was not seen when comparing mothers to males, or mothers to fathers. The ordinal ANOVA identified two specific regions that showed the pattern Females>Males>Mothers=Fathers: left medial temporal gyrus (BA 21) and left dorsolateral prefrontal cortex (BA 44). CONCLUSIONS: Parents of children with AS show atypical brain function during both visual search and emotion recognition, in the direction of hyper-masculinization of the brain. Because of the small sample size, and lack of age-matching between parents and controls, such results constitute a pilot study that needs replicating with larger samples. 相似文献
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This intervention compared the effects of two procedures on the generalization of a tacting repertoire (labeling) in 6 children with autism spectrum disorder. In one procedure the verbal antecedent stimulus “What is she doing?” appeared together with a person performing an action; in the other procedure, the antecedent stimulus was just the presence of the action. In initial tests, children emitted tacts only when the action was presented with the verbal antecedent. Thereafter, they learned to tact an action without the verbal antecedent and received tests to evaluate generalization to another action. Results indicated that in order to obtain generalization of tacting actions, it was necessary to learn to tact other actions without the verbal antecedent as well as learning to tact the action with the verbal antecedent. These findings have relevance for generalization of tacting actions from control by verbal antecedents to natural conditions and the production of spontaneous language. 相似文献