Mentalizing: What’s language got to do with it?

ABSTRACT

Understanding that people’s ideas may be false is a challenging step in Theory of Mind (ToM) development, which is accomplished around the age of 4–5 years old by typically developing (TD) children. False-belief attribution remains difficult beyond this age for certain clinical populations, such as Autism Spectrum Disorder (ASD), where delays in this realm are significant, and Developmental Language Disorder (DLD), where delays tend to be subtler. Research has identified links between ToM success and language skills, in particular complement clauses such as John thought/said that aliens landed in his garden, in TD, as well as in ASD and DLD. It has been hypothesized that these structures serve as tools for representing subjective truths. This article reports results from our experimental work further examining the link between complementation and ToM. Study 1 investigates if complements have a more privileged influence on ToM in ASD and TD children than abilities such as Executive Functions, which arguably also play a role. Study 2 determines if complementation skills in ASD support ToM reasoning or are merely implied in ToM task performance. Study 3 extends the evaluation of complementation in ToM reasoning to DLD and explores whether clinical groups of different etiologies—ASD and DLD—perform comparably for ToM once they have similar complementation skills, as expected by a linguistic determinism approach. Study 4 addresses speculation that complementation training may not be efficient to trigger improved ToM in instances of ToM impairments by empirically testing whether training on complements via a newly created iPad application can be useful for ToM remediation in both ASD and DLD. Taken together, this body of work both enhances our theoretical understanding of the language-cognition interface as well as widens our repertoire of clinical tools addressing difficulties in this domain.

Disclosure statement

No potential conflict of interest was reported by the author.

Notes

1 Note that these tasks require explicit responses. Implicit FB measures such as looking times (Onishi & Baillargeon 2005) and anticipatory looking (Senju et al. 2010; Southgate, Senju & Csibra 2007) have been interpreted to suggest that FB may arise earlier than that found with the FB tasks considered here, which instead require a decision on the part of the child. We leave aside implicit measures in the current work and simply note that various authors have argued that these may be resolved by rudimentary strategies and thus not necessarily rely on belief-reasoning (e.g., Perner & Ruffman 2005; Povinelli & Vonk 2004; Sirois & Jackson 2007).

2 The current work is thus primarily concerned with finite complements, such as “Heidi thinks/says that coconut trees grow in the Alps.” In contrast to these complements, nonfinite complements, such as “Heidi wants coconut trees to grow in the Alps,” do not have a truth index. As such, the latter cannot represent the truth in another mind (de Villiers 2005).

3 See Schick et al. (2007), however, who incorporate a low-verbal ToM task in their study of deaf children precisely to mitigate these confounds.

Additional information

Funding

This work was supported by the Swiss National Science Foundation grants PA00P1_136355 and 100014_159606.