Simulating Other Minds in Autism

forthcoming

The mere presence of another person automatically triggers powerful processes of belief computation in our brains. This spontaneous and well-established Theory of Mind (ToM) ability is considered vital for efficient social interactions. Yet, we still know little about the mechanisms allowing the brain to automatically, and without apparent mental effort, keep track of who is believing what. I argue that the role of modeling others’ attention is an overlooked and a key factor in this process. I propose the novel hypothesis that the brain makes use of an implicit model of others’ attention, recently characterized by me, featuring the simplified construct of implied motion ‘beams’ linking agents to attended objects, to support automatic belief computations. In Aim 1, supported by preliminary behavioral results, I will determine whether people perceive others’ beliefs as an implied motion between agents and belief targets, and whether this mechanism plays a functional role in spontaneous ToM. Aim 2 will apply multimodal neuroimaging and neurostimulation to define the underlying neural representations. Previous work suggests that spontaneous ToM and visual motion processing is impaired in autism. Aim 3 will examine the hypothesis that failure to engage visual motion systems when perceiving others’ beliefs explains the reduced spontaneous ToM in autism. Critically, the serotonin releasing agent MDMA is suggested to enhance both visual-motion and ToM processing. In Aim 4, I will therefore employ a double-blind, active-placebo-controlled trial to test the hypothesis that MDMA can improve spontaneous ToM in autism by upregulating this motion-based mechanism. Using an innovative behavioral intervention, I will utilize MDMA’s known effects to promote motion-encoding of others’ beliefs. My results will reveal fundamental principles of social cognition and may provide a long sought-after mechanism-focused intervention to facilitate social cognition in autism.