The human brain in action: Coordination among neural systems for planning and adapting movements

Abstract

Our ability to navigate and interact with the world around us depends on our brain's capacity to coordinate activity among its distributed and interconnected neural systems. This thesis explores key interactions that unfold in the brain as it prepares and adapts its movements. Here, a series of functional MRI studies examined human brain activity during behavioural tasks featuring real and virtual environments. The first and second of these studies investigated how the motor system influences sensory areas when preparing movements. Both studies used the same pair of delayed movement tasks to show that pre-movement activity in both auditory (Study 1) and somatosensory (Study 2) cortices carries motor-related information about the planned object-directed action. Specifically, left-versus-right hand movements, as well as eye-versus-hand movements, could be decoded from auditory and somatosensory regions well-prior to movement onset. Meanwhile, Study 3 examined widespread changes in functional brain architecture that occur when the brain is tasked with adapting to a changing environment. Leveraging recent approaches that characterize whole-brain connectivity patterns, we showed that adaptation depends on changes in how sensorimotor and visual areas functionally integrate with higher-order brain areas implicated in top-down control of behaviour. Further, we found that greater functional integration of sensorimotor areas was associated with improvements in initial learning performance across individuals. Overall, this thesis aims to further our understanding of the richly integrative nature of the human brain in action.