Individual Submission Summary

Direct link:

An Embodied Account of Executive Function Development in Infancy

Sat, March 23, 8:00 to 9:30am, Hilton Baltimore, Floor: Level 1, Peale A

Integrative Statement

This talk will link prospective motor control to early executive functions in infancy. I will outline two behavioural motion-tracking studies measuring prospective motor control and executive functions. I will discuss these findings within an embodied-cognition framework and address possible links between both early in life. Furthermore, I will provide a sneak peek on ongoing longitudinally research.
Study 1 (n = 37) investigated prospective motor control in action sequences in 14-month-olds. We know that infants adjust their reaching speed based on the type of the next action (Claxton, Keen, & McCarty, 2003). Here, we address the question whether infants also do so based on the difficulty of the same upcoming action, which would indicate a more sophisticated level of prospective motor control. We used a reach-to-place task, with difficulty of the placing action varied by goal size and goal distance, whereas difficulty of the prior reaching action was held constant. Velocity of the infants’ hand movements was measured with a motion-tracking system. Peak velocity of the first movement unit of the reaching action indicated prospective motor control. Results showed that the smaller the goal size and the longer the distance to the goal in the placing action, the slower the infants were already in the beginning prior reaching action. This was indicated by significant main effects of goal size, F (1, 33) = 4.64, p = .039, 𝛈2 = .12, and goal distance, F (1, 33) = 11.18, p = .002, 𝛈2 = .25, on peak velocity. In other words, infants moved slower in the beginning of their reach when the following action was more difficult, and moved quicker when it was easier. These findings suggest that 14-month-olds prospectively control their movements with respect to future task demands.
Study 2 (n = 53) asked whether prospective motor control and early executive functions (as two forms of action control) are linked. We used an age-appropriate version of the prospective motor task and three behavioural executive functions tasks. The executive functions tasks measured simple inhibition with a prohibition task (Friedman, Miyake, Robinson, & Hewitt, 2011), working memory with a hide-and-seek task (Garon, Bryson, & Smith, 2008), and more complex inhibition with an object retrieval task (Garon, Smith, & Bryson, 2014)). Results indicate that prospective motor control is correlated with both, simple inhibition (r = .31, p = .026) and working memory (r = .39, p = .004), but not with more complex inhibition: The quicker the infants reached successfully for toys in the motor task, the better they remembered a hidden toy’s location, and the longer they could restrain themselves from reaching for an attractive toy. These findings suggest that motor control and executive functioning are intertwined at 18 months. It is the first demonstration that low-level movement planning is related to higher-order executive control early in life. Consequently, I suggest that executive functions are grounded in an infant’s developing ability to control and plan motor actions.