Individual Differences, Imagery and the Visual Impedance Effect

Individual Differences, Imagery and the Visual Impedance Effect Lupita Estefania Gazzo Castaneda (Estefania.Gazzo@psychol.uni-giessen.de) Justus-Liebig University, Experimental Psychology and Cognitive Science, Otto-Behaghel-Str. 10F, 35394 Giessen, Germany Markus Knauff (Markus.Knauff@psychol.uni-giessen.de) Justus-Liebig University, Experimental Psychology and Cognitive Science, Otto-Behaghel-Str. 10F, 35394 Giessen, Germany Abstract The visual impedance effect describes the fact that unnecessary visual information can impede reasoning (Knauff & Johnson-Laird, 2002). We explored how this effect is modulated by individual differences in reasoning styles. The main hypothesis of the present work is that the magnitude of the impedance effect depends on the degree to which people use visual mental images during thinking. We conducted two experiments with participants with highly imagistic and highly verbal reasoning strategies. The relational inferences differed in how easily they could be visualized. Our results indicate that (1) verbalizers do not show the visual impedance effect, and (2) that people with a high preference for mental imagery try to imagine even non-visual information visually, always showing the strongest impedance by visualization. Keywords: Reasoning, individual differences, cognitive styles, visual impedance effect Introduction Many theories have been developed to explain human reasoning (Clark, 1969; Johnson-Laird & Byrne, 1991; Oaksford & Chater, 2009; Rips, 1994). A problem common to these theories is that they often exclude the possibility of individual differences in reasoning (Bacon, Handley, & Newstead, 2003; Ford, 1995). If people are asked how they solve reasoning problems, they usually report different ways of reasoning. While some people report the use of visual imagery (e.g. Egan & Grimes-Farrow, 1982; Richardson, 1977), others report more language based approaches like rehearsal (Polk & Newell, 1995), and yet others to think in a more abstract manner (Egan & Grimes-Farrow, 1982). Based on such observations, Richardson (1977) proposed the differentiation between verbalizers and visualizers. Both were conceptualized as the extremes of a continuum. Visualizers were described as people with high visual imagery, but with poor verbal abilities, and verbalizers were described with the reverse tendencies. Over the years this dichotomy was expanded in accordance with newer neurological findings, and visualizers were divided into object- and spatial- visualizers (e.g. Kozhevnikov, Kosslyn, & Shepard, 2005). While object visualizers are described as being able to construct vivid, high resolution images, spatial visualizers are described as being especially good in the processing of spatial information (Blazhenkova & Kozhevnikov, 2009). Such differences in cognitive styles are important because unlike strategies, cognitive styles should be understood as relatively stable and durable (Blazhenkova & Kozhevnikov, 2009; Riding & Cheema, The influence of cognitive styles on tasks like anagrams and mental rotation (e.g. Just & Carpenter, 1985) has already been investigated. Also, individual differences in spatial abilities and mechanical reasoning have been examined (Hegarty & Sims, 1994). Nevertheless, only few studies analyzed the influence of individual differences on deductive reasoning (e.g. Bacon et al., 2003; Ford, 1995; Sternberg & Weil, 1980). With the help of verbal protocols, Ford (1995) and Bacon et al. (2003) argued that people resolve syllogisms in two different ways. Some of the participants used a “verbal” strategy and resolved the syllogism via substitution of the terms. Other participants used a “spatial” strategy and resolved the syllogism with the help of schematic drawings which closely resembled Euler circles. However, almost no differences in performance were found (Bacon et al., 2003). Sternberg and Weil (1980) trained their participants to use either visual or rule based strategies in resolving relational inferences. One group of participants received no training. They found an interaction between skill and strategy: the effectiveness of the strategy depended on the verbal or spatial skills of the participant. More importantly, in the same study Sternberg and Weil found that a rule-based strategy lead to the fastest response times. Beyond these initial results, the question of the influence of individual differences based on imagery on other reasoning tasks like relational reasoning problems still remains open. This is surprising, insofar as the role of visual imagery on relational reasoning has been a topic of much controversy (Knauff, 2013). The Visual Impedance Effect For a long time, the role of visual imagery during reasoning was not clear. While some researchers reported imagery as a helpful tool for reasoning (Clement & Falmagne, 1986; Shaver, Pierson, & Lang, 1975), others reported opposite results (Johnson-Laird, Byrne, & Tabossi, 1989; Richardson, 1987; for a detailed review see Knauff 2013; Knauff & Johnson-Laird, 2002). In search of clarification, Knauff and Johnson-Laird (2002) postulated that these discrepancies are based on a confounding in the items. Many items which are called “visual” are visual as well as spatial. Thus, in order to investigate the role of imagery during reasoning, it is important to disentangle the visual