Using Eye-Tracking to Study how Belief-Reasoning Processes Change Across the Lifespan.

This study explored how efficiently younger (18-30 years) and older (65-80 years) adults compute belief-states of the ‘Self’ and ‘Other’. Using a computerised false-belief task, participants were shown a container with expected (e.g., sugar in a sugar jar) or unexpected (e.g., marbles in a sugar jar) contents inside. Following contents revelation, participants heard an audio question asking them to consider what either they themselves (‘Self’) or another person (‘Other’) had believed to be within the container, before seeing inside. Three images then appeared on screen: the correct answer (‘sugar’), a distracter (‘marbles’), and a novel filler item. Eye-tracking analysis revealed that, compared to younger adults, older adults took longer to disengage from the ‘distracter’ object (i.e., the object they know to actually be held in the container), in order to focus on the correct belief-state object, suggesting egocentric processing of the scenario. Behavioural results reflected this: older adults were slower and less accurate than younger adults when attributing beliefs to other people. Results suggest that different strategies are utilized across the lifespan when considering the perspectives of the ‘Self’ versus ‘Other’, and indicate that reductions in the ability to inhibit the knowledgeable egocentric viewpoint may influence social communication skills.