Linking brain and behaviour in motor sequence learning tasks

Sequence learning is a fundamental brain function that allows for the acquisition of a wide range of skills. Unlearned movements become faster and more accurate with repetition, due to a process called prediction. Predictive behaviour observed in the eye and hand compensates for the inherent temporal delays in the sensorimotor system and allows for the generation of motor actions prior to visual guidance. We investigated predictive behaviour and the brain areas associated with this processing in (i) the oculomotor system (Eye Only (EO): saccade vs. pursuit) and (ii) during eye and hand coordination (EH). Participants were asked to track a continuous moving target in predictable or random sequence conditions. EO and EH experiments were divided into 1) EO behavioural and 2) EO fMRI findings, and 3) EH behavioural and 4) EH fMRI findings. Results provide new insights into how individuals predict when learning a sequence of target movements, which is not limited to short--‐term memory capacities and that forms a link between shorter and longer--‐term motor skill learning. Furthermore, brain imaging results revealed distinct levels of activation within and between brain areas for repeated and randomized sequences that reflect the distinct timing threshold and adaptation levels needed for the two oculomotor systems. EH results revealed similar predictive behaviour in the eye and the hand, but also demonstrated enhanced coupling between the two motor systems during sequence learning. EH brain imaging findings
have provided novel insights into the brain areas involved in coordination, and those areas more associated with sequence learning. Results show evidence of common predictive networks used for the eye and hand during learning.