The interactive effects of self-other similarity, perspective-taking, disclosure, and experience, on mentalising accuracy

Mindspace theory predicts that one’s ability to understand another’s mental states is constrained by familiarity with target minds; people struggle to accurately understand others whose experiences have created different underlying patterns of relationships between personality, situations, mental states and behaviour. Prior research supports this prediction; that people with typical developmental backgrounds struggle to understand those with trauma histories (Stagaki et al., 2025), likely due to these experiential differences. From this perspective, two distinct informational requirements must be met for accurate cross-experience mentalising. First, mentalisers must know where a target is located in Mind-space. In the current study, we posit that disclosure of a trauma history provides this information, by signalling where the target should be located in Mindspace. Second, mentalisers must know what that Mind-space location implies. That is, how does the experience of childhood trauma shape the underlying pattern of relationships between certain situations, behaviours, and mental states? This knowledge may be available to the mentaliser either because a) they occupy a similar/proximal Mind-space location themselves (i.e., have a similar trauma experience and so pattern of covariances) or b) because they have learnt the differential pattern of relationships through either formal training (i.e. learning how trauma affects mental states), though direct interactions with other trauma-affected minds (thus allowing those individual minds to be represented in Mindspace and the associated model of covariances that arises from such representations), or both. This study tests the interactive effects of self-other similarity (i.e. shares a trauma history), perspective-taking (propensity to use the self as a model vs consider the target’s perspective), disclosure of trauma (or not), and experience of others with trauma, be it personal experience or professional experience, on mentalising accuracy. We hypothesise a 4-way interaction because reliance on the self as model (low perspective taking; PT) should allow for accurate inferences when the self is a good proxy for the target, i.e. there is high self-other similarity, regardless of the disclosure condition and the presence/absence of any personal/professional experience of others’ trauma . When the self is a poor model, accuracy should improve if mentalisers instead rely more on their representations of others (greater PT), but this is only likely when people both recognise that such a switch is required (i.e. they have been given a trauma disclosure and can decide whether the self is good proxy model or not) and, further, possess accurate representations of covariances between situations, behaviours, and mental states for people with trauma, to support the inference. Thus, considering the target’s perspective, as potentially distinct from one’s own, will aid accurate mental state inference more in the instance that the self is a poor model for the other and is recognised as such.