Human reasoning: Deduction rules or mental models, or both?

A good deal of energy is currently being expended into discovering the fundamental machinery underlying deductive reasoning. Is it based upon mental models (arrays) or deduction rules (propositions)? The appeal of finding a “grand unified theory” of reasoning is obvious, but the likelihood of achieving this must also be considered.

This paper discusses the use of experimental psychology in attempts to discover the processes associated with the fundamental reasoning mechanism. One particular problem is that individuals can use different strategies to solve reasoning problems. The consequences of this are assessed in relation to: (1) the assumptions underlying the experiments, (2) the choice of tasks and task presentations intended to enable the fundamental reasoning processes to be viewed directly, and (3) the power status of the theories and the nature of the evidence required to show that either theory is superior. Under close scrutiny the debate appears to be unresolvable by using empirical techniques. However, although the main conclusions are negative, it is suggested that approaches that directly investigate individual differences are likely to be useful alternatives.     

Inspection times, the change task, and the rapid-response selection task

Three experiments are reported, which are based upon the Wason four-card selection task inspection time paradigm, in which subjects solve computer-presented trials while using a mouse to indicate the card currently under consideration. Evans (1996) had shown that selected cards were inspected for longer than non-selected cards, and this was taken as support for the existence of pre-conscious heuristic processes that direct attention towards relevant aspects of a problem. However, Roberts (1998b) suggested that this inspection time effect is artefactual, due to task format induced biases. Experiment 1 utilized a "change" task: Cards were presented either as selected or not selected, and subjects changed these where necessary. This demonstrated an association between card selection and inspection time independently of one between the act of response and inspection time. Experiment 2 utilized a standard selection task, but subjects either responded within 2 s of each card presentation, or made selections with no time pressure. The curtailment of thinking time increased matching behaviour—more cards matching the terms in the rules were selected—and was replicated in Experiment 3 using a within-subjects design. Overall, the data support Evans' heuristic-analytic framework albeit with some caveats.     

Differences in nonfatal suicide behaviors among Mexican and European American middle school children.

This report describes ethnic and gender differences in suicide ideation among two large samples of middle school students in New Mexico (n = 2,140) and Texas (n = 1,302). Students completed a self-administered questionnaire on suicide ideation and psychosocial risk factors. Mexican Americans in both samples reported significantly higher prevalence of suicide ideation than did their European American counterparts. Mexican Americans were 1.8 times more likely to have high suicide ideation than European Americans. The suicide ideation risk for Mexican Americans remained unchanged in both samples after adjusting for gender, age, family structure, depression, low social support, and self-esteem. This study indicates that ethnicity plays an important role in suicidal ideation, but the mechanism remains unclear.     

Mothers’ Trait Verbal Aggressiveness as a Predictor of Maternal and Child Behavior During Playtime Interactions

This article explores associations between mothers’ trait verbal aggressiveness (VA) and maternal and child behavior during playtime interactions. Forty mothers completed a 10‐minute play period with one of their children (range = 3–8 years) and then responded to D. A. Infante and C. J. Wigley’s (1986) trait VA scale. Mothers’ trait VA was associated positively (r = .48) with their rate of directing and inversely (r =?.44) with their child’s rated cooperation. Qualitative analyses of a subset (n = 8) of interactions suggest that mothers high in trait VA used directives to control the choice, rate, and duration of activities, and used physical negative touch along with directives, more than low‐VA mothers. Behaviors associated with trait VA occur even during brief mother–child interactions in which triggers for aggressive behavior largely are absent.     

UK students and sex work: current knowledge and research issues

Available evidence, largely arecdotal suggests that students are turning to quick ways of making money such as work in the sex industry in order to balance their finances, a trend seen in other countries with similar student support and tuition fee policies. Further research is urgently needed to understand the scale of student involvement in sex work and to clarify our understanding of the factors that influence the decision to engage in it. Unfortunately a number of methodological, practical and political problems stand in the way of such research. These are discussed together with preliminary findings from an exploratory study. Copyright © 2007 John Wiley & Sons, Ltd.