Are theory of mind and metaphor comprehension causally related? A training study in middle childhood

ABSTRACT

The main aim of this study was to investigate the existence and the direction of a causal relationship between theory of mind (ToM) and metaphor comprehension during middle childhood. To this purpose, we used a compelling training design, involving 53 typically developing children (25 M, pre-training Mage = 9 years; 3 months, SD = 0;4, age-range = 8;9-9;10) who were randomly assigned either to a ToM or a metaphor comprehension training (MetaCom) condition. Training programs were matched in structure and length and already proved effective in previous studies. Before and after the intervention, children were assessed for both advanced ToM (Strange Stories task) and metaphor comprehension (Physical and Mental Metaphors task). Groups were equivalent at baseline for the focus (ToM and metaphor comprehension) and the control variables (grammar, receptive vocabulary, reading comprehension, and working memory). Results showed that the two training programs significantly differ in their effect on ToM and metaphor comprehension. While both groups significantly improved in the respective focus variables (children in the ToM training improved in ToM skills and children in the MetaCom training improved in metaphor comprehension), the MetaCom training had a significant cross-domain effect on ToM. Conversely, the ToM training did not enhance children’s metaphor comprehension. Overall, this study suggests a driving role of metaphor comprehension in the development of advanced ToM, rather than vice versa.

Acknowledgments

The authors thank the school staff, all the children who took part in the study, and their parents.

3.5.1. Data availability statement

The dataset analyzed in this study is available in the OSF repository at the link https://osf.io/zpe9r/?view_only=11d59f63b88d4688b6d1fc705cc3fdc3.

Declaration of interest statement

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article.

Notes

¹ Of the 13 participants excluded, 4 (1 in the MetaCom and 3 in the ToM group) had a diagnosis of specific learning disability or developmental delay, 4 (1 in the MetaCom and 3 in the ToM group) did not speak Italian from birth, 3 (3 in the ToM group) missed the pre- or post-test assessment, and 2 (1 in the MetaCom 1 in the ToM group) scored at ceiling at pre-training.

² This study was part of a larger training project and the MetaCom sample was included in another study (with different exclusion criteria; Tonini et al. 2022).

³ Results remained significant when we added age (in months) as a covariate: Outcomes X Time X Group interaction, F(1,46) = 4.97, p = .031, η_p² = .10.

Additional information

Funding

In the final stages, this work received support from the Italian Ministry of Research under the PRIN 2022 program, “The Fragility of Metaphors (FraMe): learning, losing, and how to train them” [project number: 2022289RNA], and from the European Research Council under the EU’s Horizon Europe program, ERC Consolidator Grant “PROcessing MEtaphors: Neurochronometry, Acquisition and Decay, PROMENADE” [101045733]. The content of this article is the sole responsibility of the authors. The European Commission or its services cannot be held responsible for any use that may be made of the information it contains.

Notes on contributors

Paola Del Sette

P. Del Sette was responsible for the conceptualization, methodology, investigation, data curation, formal analysis, writing of the original draft, and visualization. V. Bambini was responsible for the conceptualization, methodology, and writing of the original draft. E. Tonini was responsible for methodology and investigation. S. Lecce was responsible for conceptualization, methodology, writing of the original draft, and resources.