A major feat of social beings is to encode what their conspecifics see, know or believe. While various nonhuman animals show precursors of these abilities, humans perform uniquely sophisticated inferences about other people’s mental states. However, it is still unclear how these possibly human-specific capacities develop and whether preverbal infants, similarly to adults form representations of other agents’ mental states, specifically metarepresentations. We explored the neuro-cognitive bases of 8-month-olds’ ability to encode the world from another person’s perspective, using gamma-band EEG activity over the temporal lobes, an established neural signature for sustained object representation after occlusion. We observed such gamma-band activity when an object was occluded from the infants’ perspective, as well as when it was occluded only from the other person (Experiment 1), and also when subsequently the object disappeared but the person falsely believed the object to be present (Experiment 2). These findings suggest that the cognitive systems involved in representing the world from infants’ own perspective are also recruited for encoding others’ beliefs. Such results point to an early developing, powerful apparatus suitable to deal with multiple concurrent representations; and suggest that infants can have a metarepresentational understanding of other minds even before the onset of language.

EEG data 8mo infants kampis_parise_csibra_kovacsEEG Data of manuscript Kampis, Parise, Csibra & Kovács. Values depict averaged activation between 25-35 Hz on the indicated channels and conditions.