What is theory of mind? A psychometric study of theory of mind and intelligence

Theory of mind (ToM) is an essential ability for social competence and communication, and it is necessary for understanding behaviors that differ from our own (Premack & Woodruff, 1978). Recent research suggests that tasks designed to measure ToM do not adequately capture a single ToM ability (Warnell and Redcay, 2019, Quesque and Rossetti, 2020) and, instead, might be related to tasks of general cognitive ability (Coyle, Elpers, Gonzalez, Freeman, & Baggio, 2018). This hinders the interpretation of experimental findings and puts into question the validity of the ToM construct. The current study is the first psychometric assessment of the structure of ToM to date. Comparing ToM to crystallized intelligence (Gc) and fluid intelligence (Gf), the study aims to (a) understand whether ToM should be considered a monolithic ability and (b) explore whether tasks of ToM adequately assess ToM, above and beyond general cognitive ability. For this, confirmatory factor analyses (CFAs), exploratory factor analysis (EFA), and exploratory network analysis (NMA) were conducted. The results of the models largely point to the same conclusion: while ToM tasks are not merely assessing cognitive ability, they are not purely assessing a single ToM construct either. Importantly, these findings align with recent theoretical accounts proposing that ToM should not be considered a monolithic construct (Quesque and Rossetti, 2020, Schaafsma et al., 2015, Devaine et al., 2014), and should instead be explored and measured as multiple domains.