Exploring the determinants of dual goal facilitation in a rule discovery task

Wason's standard 2-4-6 task requires discovery of a single rule and leads to around 20% solutions, whereas the dual goal (DG) version requires discovery of two rules and elevates solutions to over 60%. We report an experiment that aimed to discriminate between competing accounts of DG facilitation by manipulating the degree of complementarity between the to-be-discovered rules. Results indicated that perfect rule complementarity is not essential for task success, thereby undermining a key tenet of the goal complementarity account of DG facilitation. The triple heterogeneity account received a good degree of support since more varied triple exploration was associated with facilitatory DG conditions, in line with this account's prediction that task success is associated with the creative search of the problem space. The contrast class account (an extension of Oaksford & Chater's, 1994, iterative counterfactual model) was also corroborated in that the generation of descending triples was demonstrated to be the dominant predictor of DG success. We focus our discussion on conceptual ideas relating to the way in which iterative counterfactual testing and contrast class identification may work together to provide a powerful basis for effective hypothesis testing.     

Dual-goal facilitation in Wason's 2–4–6 task: What mediates successful rule discovery?

The standard 2–4–6 task requires discovery of a single rule and produces success rates of about 20%, whereas the dual-goal (DG) version requests discovery of two complementary rules and elevates success to over 60%. The experiment examined two explanations of DG superiority: Evans' (1989) positivity-bias account, and Wharton, Cheng, and Wickens' (1993) goal-complementarity theory. Two DG conditions were employed that varied the linguistic labelling of rules (either positively labelled Dax vs. Med, or mixed-valence “fits” vs. “does not fit”). Solution-success results supported the goal-complementarity theory since facilitation arose in both DG conditions relative to single-goal tasks, irrespective of the linguistic labelling of hypotheses. DG instructions also altered quantitative and qualitative aspects of hypothesis-testing behaviour, and analyses revealed the novel result that the production of at least a single descending triple mediates between DG instructions and task success. We propose that the identification of an appropriate contrast class that delimits the scope of complementary rules may be facilitated through the generation of a descending instance. Overall, our findings can best be accommodated by Oaksford and Chater's (1994) iterative counterfactual model of hypotheses testing, which can readily subsume key elements of the goal-complementarity theory.     

Associations between myside bias on an informal reasoning task and amount of post‐secondary education

One hundred and twelve undergraduate university students completed an informal reasoning task in which they were asked to generate arguments both for and against the position they endorsed on three separate issues. Performance on this task was evaluated by comparing the number of arguments they generated which endorsed (myside arguments) and which refuted (otherside arguments) their own position on that issue. Participants generated more myside arguments than otherside arguments on all three issues, thus consistently showing a myside bias effect on each issue. Differences in cognitive ability were not associated with individual differences in myside bias. However, year in university was a significant predictor of myside bias. The degree of myside bias decreased systematically with year in university. Year in university remained a significant predictor of myside bias even when both cognitive ability and age were statistically partialled out. Copyright © 2003 John Wiley & Sons, Ltd.     

The development of metasuggestibility in children

One component of metasuggestibility is the understanding that a person's statements can influence another person's reports. The purpose of the present study was to examine the development of this understanding in school‐aged children. We produced a short video in which a boy makes a false allegation about being hit following an adult's suggestive interview. Children aged 6–13 years (N = 196) watched the video and answered open‐ended and forced‐choice questions about why the boy made a false allegation. The 6‐ and 7‐year‐olds performed poorly on all question types, whereas the 12‐ and 13‐year‐olds were at ceiling. There were developmental increases in metasuggestibility between 8 and 11 years. Our findings indicate that metasuggestibility undergoes prolonged development well into the school years. Implications for child witness training programs are discussed. Copyright © 2010 John Wiley & Sons, Ltd.     

Adapting Mindfulness-Based Cognitive Therapy for Treatment-Resistant Depression: A Clinical Case Study

Major depressive disorder (MDD) is currently ranked the third leading cause of disability in the world. Treatment-Resistant Depression (TRD) causes the majority of MDD's disability. Strikingly, 50% of individuals with MDD will fail to remit with two adequate trials of antidepressant medications, thus qualifying as treatment resistant. Current pharmacological and psychotherapeutic treatment strategies for TRD are limited in effectiveness so new interventions are needed. Mindfulness-Based Cognitive Therapy (MBCT) is a new psychotherapeutic treatment with established efficacy in preventing relapse of depression for individuals in complete remission. MBCT is a group-based, 8-week intervention that uses mindfulness meditation as its core therapeutic technique. It teaches people to have a different relationship to depressive thoughts and feelings. Strategies are focused on decreasing rumination, enhancing self-compassion, increasing acceptance and decreasing avoidance. This modified version of MCBT, which includes the use of metaphor and adaptations of the original intervention will be discussed through the clinical case of a woman with long-standing TRD. A brief review of the current MBCT literature and future directions for the treatment of TRD are discussed.     

Rolling perception without rolling motion

The texture of a rolling circle depicts the translational and rotational components of its motion. In the case of a homogeneous circle, however, visual cues to the rotational component of motion are absent. To examine how the visual system resolves undetermined motion cues, optically neutral circles were displaced so that changes in their orientation were invisible. Contextual cues systematically triggered the perception of illusory rotation, suggesting that the visual system uses contextual cues along with intrinsic surface cues to compute percepts of rolling objects. This might also explain why people rarely experience the perception of ambiguous motion.