Spontaneous Recovery in an Untrained Arm as an Assay of Interlimb Transfer of Motor Learning

• Published in: Journal of experimental psychology. Human perception and performance 2023-05, Vol.49 (5), p.725-736
• Main Authors: Kumar, Adarsh, Mutha, Pratik K.
• Format: Article
• Language: English
• Subjects: Adaptation; Adaptation, Physiological; Arm; Extinction; Extinction behavior; Female; Functional Laterality; Human; Humans; Implicit Learning; Learning; Learning transfer; Male; Motivation; Motor ability; Motor Control; Motor Development; Motor skill; Motor skill learning; Motor Skills; Psychomotor Performance; Recovery; Sensorimotor integration; Spontaneous recovery; Spontaneous Recovery (Learning); Training; Transfer (Learning); Transfer, Psychology
• ISSN: 0096-1523; 1939-1277
• DOI: 10.1037/xhp0001124

Motor skills learned with one effector are known to transfer to an untrained effector. However, which of the many mechanisms that drive learning principally predict interlimb transfer, is less clear. Recent studies of motor adaptation suggest that transfer is tied to the state of an implicit mechanism that evolves gradually during learning. Interestingly, this "slow" process also promotes spontaneous recovery, or adaptation rebound, when error feedback is clamped to zero following adaptation-extinction training. If this mechanism also drives transfer, then recovery must occur in an arm performing zero-error-clamp movements after adaptation-extinction training with the opposite arm. Here we show this to be the case in participants who undergo visuomotor learning with their left arm and perform error-clamp movements with the right, but not vice versa. The performance of control participants reveals that the absence of a rebound in this latter group is not due to an inability to recover past learning when using the left arm. Our findings firstly advance the view that interlimb transfer following visuomotor adaptation is asymmetric. Secondly, since spontaneous recovery is a hallmark of the slow process, they lend strong support to the idea that it is this specific mechanism that provides a gateway for post-learning transfer to occur. Public Significance StatementMotor learning with one limb results in performance benefits in an untrained limb, a phenomenon known as interlimb transfer of learning. Here we show that in error-driven learning, interlimb transfer is asymmetric, and is facilitated by an implicit learning mechanism that slowly updates our internal representations and produces a more stable memory trace.