Acute and chronic effects of cocaine on extinction-induced aggression.

Pigeons worked individually in a chamber containing a response key and a mirror. Pecking on the key was controlled by a multiple schedule in which a brief period of continuous food reinforcement alternated with a 5-minute period of extinction. Under baseline conditions, aggressive behavior (responding on the mirror) occurred at the onset of each extinction period. In Experiment I (acute drug administration), the aggressive behavior was decreased by doses of cocaine that had little or no effect on key pecking. Such food-reinforced responding was disrupted, however, by higher doses of cocaine. An attempt to mimic the disruptive drugs effects by a prefeeding manipulation was unsuccessful. In Experiment II (chronic drug administration), some tolerance developed to the disruptive effects of cocaine on the food-reinforced responding, except at the highest dose tested. There was no clear-cut indication of tolerance to the initial effect of cocaine on the aggressive behavior at any dose.     

Effects of self‐enhancement on agreement on personality profiles

Effects of self‐enhancement and socially desirable responding (SDR) on rater agreement for personality profiles were studied in 304 students. Dyads of participants described themselves and their peer on the Revised NEO Personality Inventory (NEO‐PI‐R) that measures 30 facets of personality. In addition, participants filled in six scales measuring self‐enhancement or SDR. Data analyses focussed on moderator and suppressor effects of SDR on the similarity between self‐reported and other reported NEO‐PI‐R profiles. Three kinds of profile agreement were distinguished: (a) normative agreement; (b) distinctive agreement and (c) profile normativeness, that is, how strongly a self‐reported personality profile resembled the average profile of all participants. There were no moderator or suppressor effects on distinctive agreement, but SDR predicted profile normativeness quite strongly. Copyright © 2009 John Wiley & Sons, Ltd.     

The impact of arbitrarily applicable relational responding on evaluative learning about hypothetical money and shock outcomes

Evaluative learning comprises changes in preferences after co-occurrences between conditioned stimuli (CSs) and an unconditioned stimulus (US) of affective value. Co-occurrences may involve relational responding. Two experiments examined the impact of arbitrary relational responding on evaluative preferences for hypothetical money and shock outcomes. In Experiment 1, participants were trained to make arbitrary relational responses by placing CSs of the same size but different colours into boxes and were then instructed that these CSs represented different intensities of hypothetical USs (money or shock). Liking ratings of the CSs were altered in accordance with the underlying bigger/smaller than relations. A reversal of preference was also observed: the CS associated with the smallest hypothetical shock was rated more positively than the CS associated with the smallest amount of hypothetical money. In Experiment 2, procedures from Relational Frame Theory (RFT) established a relational network of more than/less than relations consisting of five CSs (A-B-C-D-E). Overall, evaluative preferences were altered, but not reversed, depending on (a) how stimuli had been related to one another during the learning phase and (b) whether those stimuli referred to money or shocks. The contribution of RFT to evaluative learning research is discussed.     

The effect of test schedules on the formation of linked perceptual classes

After training conditional discriminations among selected stimuli from two perceptual classes, the emergence of novel relations involving other members of both classes was assessed using cross-class probes. The cross-class probes were presented using one of four different testing schedules. In the 2/9 test, nine different probes were presented in each of two test blocks. In the 6/3 test, three different probes were presented in each of six test blocks. In the 18/1-RND test, each of the 18 cross-class probes was presented in separate test blocks. In the 2/9 and 6/3 tests, the cross-class probes were presented in a randomized order within test block. In the 18/1-RND test, the cross-class probes were presented in a randomized sequence. In the 18/1-PRGM test, however, the cross-class probes were presented in a programmed order (i.e., the values of the stimuli in each cross-class probe were changed systematically in the succession of probe presentations). About 55% of the linked perceptual classes emerged during the 2/9, 6/3, and 18/1-RND tests. Thus the number of different probes in a test block did not influence the emergence of classes as long as the probes were presented in a random order. Virtually all classes emerged during the 18/1-PRGM test. Thus at least one ordered introduction of different cross probes resulted in the reliable emergence of linked perceptual classes. Mechanisms responsible for linked perceptual class formation are discussed along with the relation of these classes to other complex categories.     

The effects of differential and lag reinforcement schedules on varied verbal responding by individuals with autism

Variability has been shown to be a reinforceable dimension of behavior. One procedure that has been demonstrated to increase variability in basic research is the lag reinforcement schedule. On this type of schedule, a response is reinforced if it differs from a specified number of previous responses. Lag schedules are rarely used, however, for increasing response variability in applied settings. The purpose of the present study was to investigate the effects of a lag schedule of differential reinforcement on varied and appropriate verbal responding to social questions by 3 males with autism. A reversal design with a multiple baseline across subjects was used to evaluate the effects of the lag schedule. During baseline, differential reinforcement of appropriate responding (DRA) resulted in little or no varied responding. During the intervention, a Lag 1 requirement was added to the DRA (Lag 1/DRA) resulting in an increase in the percentage of trials with varied and appropriate verbal responding for 2 of the 3 participants. In addition, an increase in the cumulative number of novel verbal responses was also observed for the same 2 participants. These results are discussed in terms of reinforcement schedules that support variability, generalization, and potential stimulus control over varied responding.     

Do rats in a two-action test encode movement egocentrically or allocentrically?

Two-action tests of imitation compare groups that observe topographically different responses to a common manipulandum. The general aim of the two experiments reported here was to find a demonstrator-consistent responding effect in a procedure that could be elaborated to investigate aspects of what was learned about the demonstrated lever response. Experiment 1 was a pilot study with rats of a variant of the two-action method of investigating social learning about observed responses. Groups of observer rats (Rattus norvegicus) saw a demonstrator push a lever up or down for a food reward. When these observers were subsequently given access to the lever and rewarded for responses in both directions, their directional preferences were compared with two 'screen control' groups that were unable to see their demonstrators' behaviour. Demonstrator-consistent responding was found to be restricted to observers that were able to see demonstrator performance, suggesting that scent cues alone were insufficient to cue a preference for the demonstrators' response direction and thereby that the rats learned by observation about body movements (imitation) or lever movement (emulation). Experiment 2 assessed responding on two levers, one that had been manipulated by the demonstrator, and a second, transposed lever positioned some distance away. Demonstrator-consistent responding was abolished when actions were observed and performed in different parts of the apparatus, suggesting that observed movement was encoded allocentrically with respect to the apparatus rather than egocentrically with respect to the actor's body. With particular reference to the influence of scent cues, the results are discussed in relation to the strengths and weaknesses of this and other varieties of the two-action procedure as tests of imitation in animals and human infants. Electronic Publication     

Changing behavior within session: cyclicity and perseverance produced by varying the minimum ratio of a variable-ratio schedule

Four pigeons repeatedly chose between a fixed-ratio (FR) 20 and a variable-ratio (VR) 40 schedule of reinforcement, in which the minimum ratio of the VR cycled within each session. The minimum ratio ascended and descended (ASCDESC), descended and ascended (DESCASC), or remained constant (unchanging). In Phase 1, 2 birds (Group 1) were exposed to ASCDESC series and 2 birds (Group 2) were exposed to the DESCASC series. Choice proportions changed with the cycling minimum ratio for Group 2 but not for Group 1. In Phase 2, Group 1 subjects were exposed to the DESCASC series and Group 2 subjects were exposed to the unchanging condition. Although Group 1's choice proportions appeared to be undifferentiated in Phase 2, Group 2's choice proportions continued to cycle for more than 100 sessions. Group 2 subjects were then moved to the ASCDESC series in the third phase, and choice proportions cycled with the minimum ratio as in the first phase. The descending portion of the series was the more powerful determinant of cyclicity. Response rates also changed with the minimum component ratio, a finding that goes against the claim of universality of a rise-and-fall within-session pattern of responding. That preference varied despite the constancy of the average ratio requirement suggests nonlinear averaging in quantitatively representing a variable schedule's value. The strong perseverance observed also lends support to a growing body of literature on history effects.     

情绪反应时间动力性的研究现状与展望

情绪反应的时间动力性系指情绪反应在时间方面的动力性质,是情感风格、情绪调节、情绪恢复等内容的重要特征,其研究对促进身心健康、完善情绪理论具有重要的理论和实践意义。文章阐述了情绪反应时间动力性的内涵与外延、相关理论,以及情绪反应时间动力性的各个参数及其影响因素的研究现状,并就未来研究增加自主生理反应指标、文化背景等因素予以展望     

文化与社会赞许反应:社会个人互动的观点

在处理社会赞许反应的文化差异时,常用的两种方法为实验控制和统计控制。我们在本文中提出另一个观点。通过回顾近期的相关文献,我们指出:社会赞许反应的文化差异,反映在不同社会环境中,人们在相应的文化要求下,以不同的自我呈现方式来加强他们追求个人目标的动力。这种社会、文化与个人的对话历程乃研究文化—心理关系的核心课题。用实验或统计方法将因这个历程产生的变量从跨文化数据中剔除后,所得的结果便只有微薄的文化意义了。因此,我们反对将社会赞许反应的文化差异视为跨文化研究的噪音。相反地,我们认为跨文化研究者应认真地分析社会赞许反应的社会文化意义,以社会赞许反应作为一个窗口,管窥社会、文化与行为相生相成的关系。     

An investigation of extreme responding as a mediator of cognitive therapy for depression

Although the efficacy of Cognitive Therapy (CT) for depression is well documented, questions remain about the conditions under which CT is maximally effective, and the mechanisms by which CT is efficacious. This study examined the role of extreme responding (ER) as a mediator and predictor of relapse, as well as a predictor of acute treatment outcome. To test mediation, ER of participants in CT was compared to ER of participants receiving Behavioral Activation (BA). Results indicated that ER was not a mediator of relapse in either condition. Both CT and BA showed reductions in depression severity, however neither group showed significant changes in ER over the course of treatment. Finally, ER did not predict or moderate acute treatment outcome. The implications of these results, strengths and limitations of the current study, and future research directions are discussed.