NEURODIVERSITY OF THE BODILY SELF: PERCEPTION, ACTION, AND COGNITION IN REAL AND VIRTUAL WORLDS

The present doctoral thesis investigates some fundamental components of the bodily self, looking at the underlying mechanisms related to perception, action, and cognition and their typical and atypical development. The use of virtual reality and multimedia technologies for studying and stimulating the bodily self is discussed. Focusing on perception, the first study explored self-location accuracy in real environments and Immersive Virtual Reality (IVR), whereby children and adults with or without autism had to locate themselves in space with different sensory information available (i.e., vision and proprioception were manipulated). Results indicate that IVR headsets reduce self-location accuracy in neurotypical children and adults, possibly due to the features of visual inputs. On the other hand, preliminary evidence from a pilot study suggests that those children with autism who show increased reliance on proprioception in real environments, benefit from vision to locate themselves in IVR. We can conclude that IVR has unique sensorimotor features that interact with individual differences in sensorimotor functioning, with meaningful impact on the possibility for people to perceive, move, act, and therefore learn in virtual environments. Moving to action, the second study aimed at disentangling the role of Agency and Reward in driving action selection while participants performed a free-choice task. The probability and valence (neutral or positive) of the effect resulting from participants’ selection among 3 alternatives were manipulated. Choices and reaction times were measured to understand whether participants preferred and were faster at selecting options with higher probability of producing a neutral vs. no effect (Agency) or a positive vs. neutral effect (Reward). Children and adults with or without autism were involved. Participants’ choices and RT were not affected by Agency, whereas a more frequent selection of the option with higher probability of a positive vs. neutral effect emerged across groups, thus suggesting motivation from Reward. Participants with ASD selected less frequently the option with chance level of receiving a neutral or no effect. Since that option was the one with the greatest degree of uncertainty about the choice outcome, this choice pattern could be interpreted as a sign of reduced tolerance of uncertainty. Across tasks, conditions and age groups, participants with ASD presented shorter RT, which is a marker of reduced action planning. Future research should deepen how tolerance of uncertainty and action planning impact the way individuals with ASD make choices in everyday life situations, potentially contributing to restricted and repetitive behaviours. By an emphasis on cognition, the third study delved into the use of kinematic measures to capture motor planning and control strategies beneath cognitive performance. Neurotypical adults, children with ADHD or typical development performed an adapted Go/No-Go task while their response movement was monitored by a wearable accelerometer. Results show that neurotypical participants employed increased motor planning to correctly inhibit a prepotent response and execute the instructed alternative. Despite being accurate, children with ADHD showed reduced motor planning, which can be interpreted as a sign of impulsivity and contribute to everyday life difficulties. The general discussion presents the future of virtual reality in leveraging embodiment to shape perception, action, and cognition. While these technologies have unique potential for controlled, yet naturalistic experiences, being vastly employed in research and increasingly in clinical practice, its distinctive effects are still largely unknown.