Using extinction to promote response variability in toy play

We report the effects of extinction and positive reinforcement on the number of untrained topographies emitted by children with toys. Baseline showed no appropriate toy play. Participants were then trained individually on one topography for each toy. Previously reinforced topographies of toy play were placed on extinction, resulting in the induction of untrained topographies.     

Assessing local influence for specific restricted likelihood: Application to factor analysis

In restricted statistical models, since the first derivatives of the likelihood displacement are often nonzero, the commonly adopted formulation for local influence analysis is not appropriate. However, there are two kinds of model restrictions in which the first derivatives of the likelihood displacement are still zero. General formulas for assessing local influence under these restrictions are derived and applied to factor analysis as the usually used restriction in factor analysis satisfies the conditions. Various influence schemes are introduced and a comparison to the influence function approach is discussed. It is also shown that local influence for factor analysis is invariant to the scale of the data and is independent of the rotation of the factor loadings. The authors are most grateful to the referees, the Associate Editor, and the Editor for helpful suggestions for improving the clarity of the paper.     

Reinforcer frequency and restricted stimulus control.

Stimulus control was evaluated in 3 individuals with moderate to severe mental retardation by delayed identity matching-to-sample procedures that presented either one or two discrete forms as sample stimuli on each trial. On pretests, accuracy scores on one-sample trials were uniformly high. On two-sample trials, the correct stimulus (i.e., the one that subsequently appeared in the comparison array) varied unpredictably, and accuracy scores were substantially lower, suggesting that both sample stimuli did not exert stimulus control on every trial. Subjects were then given training sessions with the one-sample task and with a new set of four stimuli. For two of the stimuli, correct matching responses were followed by reinforcers on a variable-ratio schedule that led to a high reinforcer rate. For the other two stimuli, correct responses were followed by reinforcers on a variable-ratio schedule that led to a substantially lower reinforcer rate. Results on two-sample tests that followed showed that (a) on trials in which comparison arrays consisted of one high reinforcer-rate and one low reinforcer-rate stimulus, subjects most often selected the high-rate stimulus; and (b) on trials in which the comparison arrays were either two high reinforcer-rate stimuli or two low reinforcer-rate stimuli and the samples were one high reinforcer- and one low reinforcer-rate stimulus, accuracy was higher on trials with the high-rate comparisons. These results indicate that the frequency of stimulus control by high reinforcer-rate samples was greater than that by low reinforcer-rate samples. Following more training with the one-sample task and reversed reinforcement schedules for all stimuli, the differences in stimulus control frequencies on two-sample tests also reversed. These results demonstrate experimental control by reinforcement contingencies of which of two sample stimuli controlled selections in the two-sample task. The procedures and results may prove to be relevant for understanding restricted stimulus control and stimulus overselectivity.     

Contrast and autoshaping in multiple schedules varying reinforcer rate and duration

Thirteen master pigeons were exposed to multiple schedules in which reinforcement frequency (Experiment I) or duration (Experiment II) was varied. In Phases 1 and 3 of Experiment I, the values of the first and second components' random-interval schedules were 33 and 99 seconds, respectively. In Phase 2, these values were 99 seconds for both components. In Experiment II, a random-interval 33-second schedule was associated with each component. During Phases 1 and 3, the first and second components had hopper durations of 7.5 and 2.5 seconds respectively. During Phase 2, both components' hopper durations were 2.5 seconds. In each experiment, positive contrast obtained for about half the master subjects. The rest showed a rate increase in both components (positive induction). Each master subject's key colors and reinforcers were synchronously presented on a response-independent basis to a yoked control. Richer component key-pecking occurred during each experiment's Phases 1 and 3 among half these subjects. However, none responded during the contrast condition (unchanged component of each experiment's Phase 2). From this it is inferred that autoshaping did not contribute to the contrast and induction findings among master birds. Little evidence of local contrast (highest rate at beginning of richer component) was found in any subject. These data show that (a) contrast can occur independently from autoshaping, (b) contrast assays during equal-valued components may produce induction, (c) local contrast in multiple schedules often does not occur, and (d) differential hopper durations can produce autoshaping and contrast.     

不同历史时期谬误研究的特点

本文主要讨论了不同时期逻辑学家对逻辑谬误研究的特点。古希腊时期对谬误作出全面系统研究的是亚里士多德。亚里士多德对谬误的解决方法一般地说是经验的,没有形成一套行之有效的规则。文艺复兴时期,培根等人批判经院哲学,探讨了人类产生谬误的根源。这时期的谬误研究特点是：一是重视在归纳法的应用中产生的谬误;二是突出逻辑问题。现代逻辑学家如柯比等人则在前人的基础上,对谬误作出了更全面、更精确的分类,并且对各种谬误的解释和举例也更确切,从而使谬误理论更好地为实践服务。     

Forming all pairs in a minimal number of steps

How can N individuals in a closed space meet and greet each other most efficiently? This paper presents a general solution to this problem—an algorithm or “dance” that will achieve universal pairing in the least possible number of moves or steps. A proof of the suggested algorithm is included, showing that it guarantees that every two participants will greet each other once and only once, and that no procedure with this property can be accomplished with fewer steps. Slightly different procedures are required for the odd and even cases. The algorithm has been applied in classroom settings, and could be applied in any social setting where the objective is to initiate efficiently a sense of group cohesion and common purpose.     

When Is Genetic Reasoning Not Fallacious?

Attempts to evaluate a belief or argument on the basis of its cause or origin are usually condemned as committing the genetic fallacy. However, I sketch a number of cases in which causal or historical factors are logically relevant to evaluating a belief, including an interesting abductive form that reasons from the best explanation for the existence of a belief to its likely truth. Such arguments are also susceptible to refutation by genetic reasoning that may come very close to the standard examples given of supposedly fallacious genetic reasoning.     

认知神经科学视角的催眠研究述评

催眠被广泛的应用在临床心理治疗中, 但是, 关于催眠方面的研究却相当匮乏, 而且相当模糊。近年来, 随着fMRI, ERP和PET等技术的引入, 我们对催眠引导和催眠暗示有了更加深入的理解。对于疼痛和幻觉的研究表明, 至少对于高暗示性被试而言, 催眠暗示可以引起与真实刺激同样的大脑皮层的激活; 而催眠后暗示对于注意策略的调控, 可以使原有的认知过程发生改变, 其中之一是使用催眠后暗示来抑制“Stroop效应”语义加工过程; 催眠后遗忘更是实现了内隐记忆和外显记忆遗忘的分离。未来研究者将继续从探讨催眠本身的神经属性和催眠暗示所引起的认知过程的改变两个角度去认识催眠, 揭开催眠的实质。     

Epistemic instrumentalism,exceeding our grasp

In the concluding chapter of Exceeding our Grasp Kyle Stanford outlines a positive response to the central issue raised brilliantly by his book, the problem of unconceived alternatives. This response, called "epistemic instrumentalism", relies on a distinction between instrumental and literal belief. We examine this distinction and with it the viability of Stanford's instrumentalism, which may well be another case of exceeding our grasp.     

Human content in affect-inducing stimuli: A secondary analysis of the international affective picture system

We report a secondary analysis of the international affective picture system (IAPS), the broadest available standardized sample of emotional stimuli, which confirmed our prediction that the distribution of slides across the valence and arousal dimensions would be related to human versus inanimate slide content. Pictures depicting humans are over-represented in the high arousal/positive and high arousal/negative areas of affective space as compared to inanimate pictures, which are especially frequent in the low arousal/neutral valence area. Results pertaining to dominance ratings and gender differences in valence and arousal ratings further suggest that there are qualitative differences between emotional reactions to animal or human slide content and responses to nonsocial still photos. Researchers need to be mindful of this distinction when selecting affect-inducing stimuli.