Sensorimotor Neuroscience Lab

Furthermore, the consequence group showed increased recall and savings of the learned visuomotor mapping one week later despite exposure to a competing mapping during initial learning—evidence of greater motor memory consolidation

Crucially, we found that learning generalized to a greater extent in the group who experienced the adverse physical consequence. Specifically, this group demonstrated (a) increased interlimb-transfer on a precision walking task and (b) generalization to an obstacle-avoidance task

Because of our innate drive for safety, and the fact that balance is fundamental to movement, we hypothesized that the physical consequence would enhance motor memory. We found that both groups experienced similar magnitude foot-placement errors and adapted at similar rates

2 groups adapted to (a) a new prism-induced visuomotor mapping during (b) a precision walking task. Notably, 1 group experienced an unexpected slip perturbation during foot-placement errors. We tested how this physical consequence affected (c) generalization and (d) consolidation

For reaching, we found evidence of initial recall, though neither group demonstrated savings (Fig.1). In contrast, both walking groups showed recall and savings. Additionally, we found that challenging balance enhanced savings during walking (Fig.2).

We found that challenging balance did not disrupt visuomotor adaptation during reaching (Fig.1) or walking (Fig.2). We then probed initial recall and savings (i.e., faster relearning) by having participants repeat the adaptation protocol one week later.

We had four groups of participants (n = 12 each) adapt to a novel visuomotor mapping induced by prism lenses while performing a standing-based reaching or walking task, with and without a manipulation that challenged balance.

Gaze behaviour predicted step choice. We suggest acquiring environmental information, being certain of one’s action, & the effort to move are factors that interact to dictate how to direct gaze and decide where to step; how one assigns value to these factors differs across people

Some participants spent more time looking at both targets and tended to step onto the more effortful but visually-certain location. Others usually ignored looking at the more effortful target and chose to step to the other, more visually-uncertain target, thus minimizing energy.

Participants decided which of 2 targets to step on as they walked. One target varied in its blurriness, creating uncertainty in the location of its centre. The other target required a wider, more effortful step, but it was easier to locate its centre to ensure stepping accuracy.

What drives decisions of where we look and step when walking in complex environments? In our latest paper in @CurrentBiology @CellPressNews, we suggest these decisions depend on the value we assign to information gain, being certain of our actions, and conserving energy. Thread

Looking for Grad students (PhD/MSc) to join our lab in beautiful Vancouver from Sept 2021! Projects related to how we use visual information to navigate our world. Details: sfu.ca/smnl/prospective-trai…. Please RT. Come for the research, stay for the adventure 🏔

We found no effects of age on adaptation or savings. However, older adults showed reduced initial recall of the mapping (greater first adaptation trial error one-week later)(Fig.2). We also found that increased age significantly associated with reduced initial recall (Fig.3).

Three groups (n = 12 each) of participants (young: 20–39 yrs; middle-aged: 40–59 yrs; older: 60–80 yrs) learned a new visuomotor mapping induced by prism lenses (1A) during a precision walking task (1B). We assessed savings (defined as faster relearning) one-week later (1C).

(5/5) We propose that challenging balance increases the value assigned to the internal model formed during learning, whether this be from a greater need to control motion at different body segments or greater perceived threat, thus making it more generalizable.

(4/5) We found that both (A) reaching groups and both (B) walking groups showed generalization to their equivalent, non-adapted task. However, the balance-challenged groups showed significantly greater generalization than the balance-unchallenged groups.