Memory Span as a Predictor of False Belief Understanding

Article excerpt

Recent work on the child's developing theory of mind has identified the development of working memory span as a factor which contributes to children's developing understanding of false belief (Keenan, Olson & Marini, 1998). Keenan et al. argued that working memory might be a mechanism which is partially responsible for the developmental change in false belief understanding observed around age 4. In the present study, 60 children aged 4 to 5 were given a set of false belief tasks, a test of language development, and a measure of working memory span. The goal of the study was to replicate the findings of Keenan et al., testing the hypothesis that a measure of working memory would predict children's performance on a set of false belief tasks while controlling for age and language ability. The findings supported the hypothesis and are discussed in terms of the role of working memory as a possible mechanism which drives the development of false belief understanding observed around age 4.

Given more than a decade of research on the child's development of a "theory of mind," there is a general agreement that around age 4, children begin to acquire an understanding of their own and others' minds. During the preschool years, children come to understand that people act on the basis of their beliefs, and furthermore, that these beliefs can faithfully represent or misrepresent reality (Olson, 1989). This has been demonstrated largely using variants of Wimmer and Perner's (1983) classic "unexpected transfer" task (e.g., Perner, Leekam & Wimmer, 1987) but similar findings have been demonstrated using tests of "informational access," assessing the child's understanding of how beliefs are determined by the quality and nature of the information available (e.g., Keenan, Ruffman, & Olson, 1994; Ruffman, Olson, & Astington, 1991).

In a typical variant of the false belief task (Baron-Cohen, Leslie & Frith, 1985), one puppet, "Sally" hides an object in a green box and then Sally leaves to go outside and play. While Sally is absent, another puppet, "Ann," takes the object and moves it to a red box. When Sally returns, the child participant who has watched this drama unfold is asked to predict where Sally would search for her chocolate or where Sally will think the chocolate is located. At 3 years of age, a majority of children fail this task, stating that Sally would look in the red box, where the chocolate is really located (Wimmer & Perner, 1983), demonstrating a failure to take into account Sally's false belief. On the other hand, most 4-year-olds will correctly state that Sally will look in the green box, where she falsely thinks the chocolate is located. The 4-year-olds recognize both that Sally would hold a false belief due to her restricted access to the events that have transpired and that she would act on the basis of her false belief, not on the basis of the current reality of the situation.

The consensus in theory of mind research is that the false belief task acts as a marker for the development of a representational theory of mind (e.g., Astington, 1993; Gopnik & Wellman, 1994; Keenan et al., 1994; Perner, 1991, Ruffman, Olson, Ash, & Keenan, 1993; Wellman, 1990; see however Carpendale & Chandler, 1996 for an opposite view). When children recognize that people act on the basis of their beliefs, even when these beliefs do not match the current reality of a situation, we can properly say the child understands the mind as a representational medium, that is, that the mind represents information and furthermore, that these representations can correspond or fail to correspond with reality (Perner, 1991). The development of a representational theory of mind enables individuals to understand the importance of subjectivity and individual perspectives in mental life (Carpendale & Chandler, 1996).

According to a number of recent reviews in the field, the question of what mechanisms drive children's developing theory of mind has been largely left without a reasonable explanation (Flavell & Miller, 1998; Taylor, 1996). …