Acquisition and adaptation of de novo sensorimotor mappings скачать в хорошем качестве

Acquisition and adaptation of de novo sensorimotor mappings

Neural Control of Movement 2020 Award Winners Symposium The first goal of our study was to use behavioral manipulations and computational modeling to distinguish between model-free and model-based reinforcement learning processes. Two groups of participants trained to move a cursor between a paired start-end position. One group was provided with instructions – the shortest sequence of key. Following acquisition, both groups were tasked with moving the cursor between novel start-end position pairings. While the group trained with instructions was less able to generalize their learning to the novel start-end position pairings. This suggests that instruction blunted learning of the underlying sensorimotor mapping. In a follow-up experiment, we probed the acquisition time course of the sensorimotor mapping without any instruction. We found that with training, participants were able to generalize and perform progressively further future-state planning (i.e. the number of keypresses required to move from the start to the end position). We modeled these behavioral results using six increasingly complex reinforcement learning models: from simple state-action reinforcement to using the learned action-mapping for planning. We found that a combination of both model-free learning and model-based planning was necessary to account for learning and generalization of the new sensorimotor mapping. The second goal of our study was to show that the newly learned sensorimotor mapping can be adapted to a perturbed environment. To demonstrate this adaptation effect, we shifted the mapping of each finger to the finger immediately adjacent (e.g. the middle finger now does what was initially learned by the ring finger). Participants were able to adapt to this configuration more readily than they could a completely new, random mapping. These findings show that sensorimotor mappings learned de novo are adaptable shortly after acquisition and that adaptation processes are not limited to well-practiced, continuous movements.