Researchers from the University of Cambridge and the University of Plymouth have shown that follow-through – such as when swinging a golf club or tennis racket – can help us to learn two different skills at once, or to learn a single skill faster. The research, published in the Current Biology, provides new insight into the way tasks are learned, and could have implications for rehabilitation, such as re-learning motor skills after a stroke.
The researchers found the particular motor memory, which is active and modifiable in the brain at any given time depends on both lead-in and follow-through movement, and that skills which may otherwise interfere can be learned at the same time if their follow-through motions, are unique.
The researchers examined either the presence or absence of interference by having participants learn a “reaching” task in the presence of two opposite force-fields to determine whether they learned a separate motor memory for each task, or a single motor memory for both. They found the specific motor memory, which is active at any given moment, depends on the movement that will be made in the near future. When a follow-through movement was made that anticipated the force-field direction, there was a substantial reduction in interference. This suggests that different follow-throughs may activate distinct motor memories, allowing people to learn two different skills without them interfering, even when the rest of the movement is identical. However, while practicing a variable follow-through can activate multiple motor memories, practicing a consistent follow-through allowed for tasks to be learned much faster.
“There is always noise in our movements, which arrives in the sensory information we receive, the planning we undertake, and the output of our motor system,” David Franklin, PhD, Wellcome Trust RCD Fellow at Cambridge’s Department of Engineering and a senior author on the research, stated in a press release. “Because of this, every movement we make is slightly different from the last one even if we try really hard to make it exactly the same – there will always be variability within our movements and therefore within our follow-through as well.”
He added, “This research suggests that this variability has another very important point – that it reduces the speed of learning of the skill that is being practiced.”
The research may also have implications for rehabilitation, such as re-learning skills after a stroke. When trying to re-learn skills after a stroke, many patients exhibit a great deal of variability in their movements.
“Since we have shown that learning occurs faster with consistent movements, it may therefore be important to consider methods to reduce this variability in order to improve the speed of rehabilitation,” Ian Howard, PhD, associate professor at the University of Plymouth’s Centre for Robotics and Neural Systems and the paper’s lead author, stated in the release.
Franklin D. The value of follow-through devices from motor learning depending on future actions. Curr Biol. 2015; in press.
Disclosure: The work was supported by the Wellcome Trust, Human Frontier Science Program, Plymouth University and the Royal Society.