Persistence of stereotypic behavior: examining the effects of external reinforcers

Basic research has shown that behavioral persistence is often positively related to rate of reinforcement. This relation, expressed in the metaphor of behavioral momentum, has potentially important implications for clinical application. The current study examined one prediction of the momentum metaphor for automatically reinforced behavior. Participants were 3 children who had been diagnosed with an autism spectrum disorder and who engaged in stereotypic behavior maintained by automatic reinforcement. Results suggested that stereotypic behavior was more resistant to disruption following periods of access to preferred stimuli delivered on a variable-time schedule than following periods without access to preferred stimuli. The implications of these findings for the treatment of automatically reinforced behavior are discussed.     

Forgetting congruent and incongruent stereotypical information

In 2 studies, the authors investigated the directed-forgetting effects of stereotypically congruent, incongruent, and irrelevant information, after the in-group (Swedish) and out-group (immigrant) social categories had been subliminally primed. Because of recent theories of the role of attention and level of processing in the cognitive development of stereotypes, we hypothesized that directed-forgetting effects would be found for stereotype-congruent and irrelevant information but not for stereotype-incongruent information. The results supported our hypothesis, suggesting that the level of processing demanded by the type of information (regardless of whether congruent, incongruent, or irrelevant) may moderate directed-forgetting effects. The authors discussed the social implications of the results.     

Effects of increased complexity of visuo-motor transformations on children's arm movements

The effects of increasing complexity of visuo-motor transformations on movement were examined in 4-, 6-, and 8-year-old children and adults. Participants performed a 'center-out' drawing task under three increasingly complex conditions: (1) Normal transformation: The target, line path and hand position were fully visible, in the horizontal plane, throughout the movement. (2) Aligned transformation: The target and line path were displayed horizontally above the workspace, with vision of the arm/hand occluded. (3) Vertical transformation: The target and line paths were presented on a vertical computer monitor with vision of the arm/hand occluded. Results showed that with increasing age, movements became faster, straighter, and smoother. The 4- and 6-year-old children were more variable in their specification of movement direction than the 8-year-old children and the adults, and were also more affected by the complexity of the transformation. This suggested that besides the complexity of the visual transformation, the familiarity/experienced environment might also play a role in 'sharpening' the transformation maps represented in movement planning.     

The association between implicit and explicit prejudice: the moderating role of motivation to control prejudiced reactions

The main aim of the present research was to assess the relationship between implicit and explicit ethnic attitude measures and to examine the impact of motivation to control prejudiced reactions on this relation. Implicit ethnic prejudice was assessed by a response latency measure, and a self-report modern prejudice scale was used to assess explicit prejudice. The results showed that an association between implicit and explicit attitudes was observed only when the explicit attitude measure was corrected for motivational bias. The findings are discussed in relation to previous research reporting either association or dissociation between implicit and explicit attitude measures.     

Justification of Induction: Russell and Jin Yuelin. A Comparative Study

Jin Yuelin (1895–1984), a Chinese logician and philosopher, is greatly influenced by Hume's and Russell's philosophies. How should we respond to Hume's problem of induction? This is an important clue to understand Jin's whole philosophical career. The first section of this paper gives a brief historical review of Russell and Jin. The second section outlines Hume's skeptical arguments against causality and induction. The third section expounds Russell's justification of induction by discussing his views on Hume's skepticism, causality, principle of induction, and empirical postulates. The fourth section clarifies Jin's justification of induction by discussing his critique of Hume's epistemology and his arguments for the reliability of causality and the eternal truth and apriority of the principle of induction. The final section compares Jin's justification of induction with Russell's and concludes that there are similarities and differences between their projects and that both their attempts fail. This paper takes the similar responses to the problem of induction by Jin and Russell to demonstrate the communication that there has been between Chinese philosophers and the Western ones.     

Proper Names,Contingency A Priori and Necessity A Posteriori

After a brief review of the notions of necessity and a priority, this paper scrutinizes Kripke's arguments for supposedly contingent a priori propositions and necessary a posteriori propositions involving proper names, and reaches a negative conclusion, i.e. there are no such propositions, or at least the propositions Kripke gives as examples are not such propositions. All of us, including Kripke himself, still have to face the old question raised by Hume, i.e. how can we justify the necessity and universality of general statements on the basis of sensory or empirical evidence?     

Differences between elite,junior and non-rowers in kinematic and kinetic parameters during ergometer rowing

This paper presents an analysis of the rowing parameters of differently skilled rowers. The study focuses on technique dependency on stroke rate. Five elite, five junior and five non-rowers participated, and the biomechanics of rowing on an ergometer was analyzed at stroke rates of 20, 26 and 34 str/min. The results show that elite rowers use a similar, consistent rowing technique at all stroke rates, the technique of junior rowers follows similar principles, while the technique of non-rowers varies. Elite rowers’ stroke length, handle motion and body posture do not change with stroke rate while the ratio of stroke phases, maximum forces, stroke work and joint loadings are constant at the same stroke rate but dependent on stroke rate. Junior rowers with stroke rate change also the stroke length. In non-rowers the differences can be observed in the handle motion and body posture during the stroke, their stroke length changes with stroke rate while the ratio of stroke phases stays constant. Although different movement execution is evident and variable with stroke rate, non-rowers demonstrate a consistent pattern at the same stroke rate. On the basis of the results, the crucial parameters that differentiate elite, junior, and non-rowers are identified.     

Measuring and testing awareness of emotional face expressions

Comparison of behavioural measures of consciousness has attracted much attention recently. In a recent article, Szczepanowski et al. conclude that confidence ratings (CR) predict accuracy better than both the perceptual awareness scale (PAS) and post-decision wagering (PDW) when using stimuli with emotional content (fearful vs. neutral faces). Although we find the study interesting, we disagree with the conclusion that CR is superior to PAS because of two methodological issues. First, the conclusion is not based on a formal test. We performed this test and found no evidence that CR predicted accuracy better than PAS (p = .4). Second, Szczepanowski et al. used the present version of PAS in a manner somewhat different from how it was originally intended, and the participants may not have been adequately instructed. We end our commentary with a set of recommendations for future studies using PAS.