Técnicas de procedimiento para el análisis de datos

Various theories have been suggested trying to explain the strong empirical evidence indicating a connection between IC and belief-reasoning.

One prominent theory is referred to as “emergence theory” (Carlson et al., 2002; Perner & Lang, 1999; Sabbagh et al., 2006). According to this theory, IC is a necessary prerequisite for the development of belief attribution. The theory suggests that it is necessary for a child to inhibit his or her impulses and to be able to attend to new situations in order to pay attention to other people’s mental states. It also assumes that IC is not necessary anymore for attributing beliefs once a child has acquired a fully efficient ToM. Emergence theory states that from this point on, ToM reasoning modules may work independently of EF abilities such as IC.

Richer versions of emergence theory suggest that IC may be necessary in order to become exposed to social situations during which the children can then learn about discrepancies between mental states and reality. This view is backed by a study that found advanced IC abilities in Chinese preschoolers when compared to U.S. preschoolers (Sabbagh et al., 2006). Although IC abilities predicted belief-reasoning performance in both samples, Chinese preschoolers showed no superior belief-reasoning abilities. The authors argue that this finding may be due to the fact that U.S. preschoolers grow up with more siblings and are thus exposed to more everyday social experiences in which they can learn about others’ mental states. Further evidence comes from a longitudinal study showing that early IC performance predicts later belief-reasoning performance in children between 3 and 4 years of age (Flynn, 2007). Early belief-reasoning abilities on the other hand did not emerge as a predictor for IC performance. Emergence theory can thus account for some of the behavioral results that show a relationship between IC and belief- reasoning in 3 to 5 year old children. However, it cannot account for findings that IC performance and belief-reasoning abilities are also correlated in adulthood and old age (German & Hehman, 2006; McKinnon & Moscovitch, 2007)

Another theory, dubbed “expression” or “performance” theory attempts to explain the connection between IC and belief-reasoning from childhood to old age (Kloo & Perner, 2003; Perner & Lang, 1999; Siegal & Varley, 2002). Expression theory proposes that belief-reasoning tasks require the suppression of the true state of affairs in favor of one’s

own or others’ mental states by means of IC (Hughes & Russell, 1993; Russell et al., 1991). As such it is argued that young children may possess a concept of belief long before they actually are able to use it. Only their poor IC abilities may hamper the expression of their ability to attribute mental states.

Expression theory therefore implies that decreasing inhibitory demands in belief- reasoning tasks could actually improve children’s belief-reasoning performance. However, this prediction of expression theory is not true. Explanation versions of false-belief tasks with little to no inhibitory demands are as hard for children as the original task versions (Hughes, 1998; Perner et al., 2002a; Perner & Lang, 1999). It could be that only children at an intermediate belief-reasoning level with intermediate IC abilities are aided by decreasing inhibitory task demands (Wellman et al., 2001). This hypothesis has not been tested empirically, though. Further, according to the expression theory, a lack of inhibitory control and thus belief-reasoning would imply that young children will typically answer a false-belief question with the actual state of reality. This, however, has not been observed either. As a matter of fact, children who do not pass false-beliefs tasks yet answer questions about false-beliefs at chance level, suggesting that they do not possess any concept of mental states at all (Wellman et al., 2001). Due to several arguments against expression theory, this theory has little explanatory power regarding the relation between IC and the attribution of beliefs.

Another theory suggests that belief-reasoning may be a prerequisite for IC (Perner, 1998; Perner & Lang, 1999). According to this theory, children first have to understand that mental states have causal power, meaning that these states are the driving force behind people’s actions. IC on the other hand requires the subject to realize that a tendency exists towards executing a wrong action and that this action needs to be inhibited. Hence, this tendency within exhibits causal power as well. The understanding that mental states possess causal power may therefore also foster IC, which requires an understanding of causal power as well. Evidence for this theory comes from the finding that hyperactive children suffering from an impairment in IC show relatively unimpaired belief-reasoning abilities (Sodian et al., 2003).

More advanced theories concerning the IC / belief-reasoning relation propose a bi- directional relationship between the two latter concepts. The acquisition of a ToM in this theory may lead to improved IC which then facilitates mental state attribution, especially in situations with high inhibitory demands (Sodian & Hülsken, 2005).

Yet another class of more elaborate theories has focused on various components underlying the attribution of mental states. According to these theories, mental state attribution is supposed to require a core ToM system (“ToM Mechanism; ToMM;) as well as a co-opted system, also referred to as a “selection processor” (Leslie et al., 2004;

Leslie et al., 2005). This selection processor is related to IC. According to this theory, the maturation of belief-reasoning abilities may rely on an improvement in IC skills with the core belief-reasoning system remaining relatively stable. However, accounts that belief- reasoning performance in early childhood is not facilitated by lowering executive task demands oppose this view (Leslie et al., 2004; Wellman et al., 2001). The power of this approach lies nevertheless in its ability to explain instances of compromised belief- reasoning capacities while showing intact IC as well as of relatively intact belief-reasoning with compromised IC, as found in children with ADHD (Sodian et al., 2003).

In sum, a series of hypotheses has attempted to explain results suggesting a strong relation between belief-reasoning and IC. So far no hypothesis has been able to sufficiently account for all existing behavioral results. More elaborate hypothesis may be needed to explain and predict phenomena related to the connection between IC and belief-reasoning. This matter will be discussed in more detail with respect to the present study’s results in the discussion section of this paper.

As briefly mentioned in the previous section, individuals with disorders such as autism or ADHD show deficits to varying extents in either belief-reasoning or IC, corroborating findings of an IC / belief-reasoning connection. Systematic investigations of impaired IC and belief-reasoning functioning in autism and ADHD can provide insights about the relation between the two latter concepts. Findings from patients with compromised IC / belief-reasoning abilities will be discussed next.