Preserved higher-order mentalising during strategic interactions after medial prefrontal cortex damage

Mentalising, the ability to infer the beliefs and intentions of others, is essential for successful social interaction. Previous studies have implicated the medial prefrontal cortex in mentalising, but whether this region is necessary for higher-order mentalising remains unclear. Here we show that people with focal damage to the medial prefrontal cortex retain the ability to engage in higher-order mentalising during a strategic social game. We compare their performance with patients with brain damage in other regions and lesion-free participants. Individuals with medial prefrontal cortex damage achieve similar rewards and use comparable mentalising strategies, but they are slower when making strategic decisions. Computational modelling indicates that this slowing reflects a greater tendency to require evidence before committing to a choice. Voxel-based lesion-symptom mapping identifies medial prefrontal regions linked to altered decision processes rather than mentalising. These findings suggest that the medial prefrontal cortex supports strategic decisions while higher-order mentalising remains intact.