Individual differences in deductive reasoning: Formal and Thematic Wason's THOG problems

This paper was presented at XIII Conference of the European Society for Cognitive Psychology. A posterior version was published in Psicothema (2007), 19 (2), 206 - 211This study forms part of a wider research project aimed at investigating relationships between cognitive skills and performance on experimental reasoning tasks (Stanovich, 1999; Stanovich & West, 1998). The study aims to replicate and expand our previous studies of individual differences, both in conditional reasoning (Seoane, Valiña, Ferraces & Martín, 1997; Valiña, Seoane, Ferraces & Martín, 1993; 1995; 2000) and disjunctive reasoning (Martín, Seoane, Valiña & Ferraces, 1998; Martín & Valiña, 2002; 2003). Specifically, this study centred on individual differences in a reasoning task: The THOG problem (Wason, 1977; Wason & Brooks, 1979). This is one of the tasks conceived by Peter Wason to “explore the nature of thought” (Evans & Johnson-Laird, 2003, p. 178). Concretely, the aims of this study were: (1) To investigate the relationships between the subjects´ performance on various computerized tests of cognitive abilities and the subjects´ reasoning with the THOG problem, and (2) to analyze the influence of rule content (formal and different thematic versions of the task) and instructions (standard / oneother) on the subjects´ performance with the THOG proble