Infants’ Motor Proficiency and Statistical Learning for Actions

Abstract

Prior research has shown that infants learn statistical regularities in action sequences better than they learn non-action event sequences. This is consistent with current theories claiming that the same mechanism guides action observation and action execution. The current eye-tracking study tested the prediction, based on these theories, that infants’ ability to learn statistical regularities in action sequences is modulated by their own motor abilities. Eight- to eleven-month-old infants observed an action sequence containing two deterministic action pairs (i.e., action A always followed by action B) embedded within an otherwise random sequence. One pair was performed with a whole-hand grasp. The second pair was performed with a pincer grasp, a fine motor skill that emerges around 9 months of age. Infants were then categorized into groups according to which grasp was dominant in their motor repertoire. Predictive looks to correct upcoming actions during the deterministic pairs were analyzed to measure whether infants learned and anticipated the sequence regularities. Findings indicate that infants learned the statistical regularities: across motor groups, they made more correct than incorrect predictive fixations to upcoming actions. Overall, learning was not significantly modulated by their dominant grasping abilities. However, infants with a dominant pincer grasp showed an earlier increase in correct predictions for the pincer grasp pair and not the whole-hand grasp. Likewise, infants with a dominant whole-hand grasp showed an early increase in correct predictions for the pair performed with a whole-hand grasp, and not the pincer grasp. Together, these findings suggest that infants’ ability to learn action sequences is facilitated when the observed action matches their own action repertoire. However, findings cannot be explained entirely by motor accounts, as infants also learned the actions less congruent with their own abilities. Findings are discussed in terms of the interplay between the motor system and additional non-motor resources during the acquisition of new motor skills in infancy.

Action prediction during real‐time parent‐infant interactions

“…for instance, one screen-based experiment using action stimuli found anticipation rates of 20%-30% in toddlers (out of all gaze fixations), while a similar study using more complex visual stimuli with infants found anticipation rates of only 5% (Monroy et al, 2017b). In our study, infants were engaged in their own manual actions while monitoring those of their parents, and they were significantly less likely to anticipate when holding objects of their own.…”

“…Infants become more precise at anticipating an observed action once they have acquired the requisite motor skill (Monroy et al, 2017b;Senna et al, 2016;Stapel et al, 2016), a finding that is not explained by general development. For instance, Monroy et al (2017b) took advantage of the natural variation in the emerging motor skills of young infants to show that those infants who had acquired a specific motor skill (e.g., a pincer grasp) were more precise at anticipating that action than infants of the same age who had not yet mastered that motor skill. Infants also demonstrate activation over their motor cortex when anticipating an action outcome (Monroy et al, 2019;Southgate et al, 2010).…”

Finding events in a continuous world: A developmental account

“…Additionally, researchers have identified links between action production and perception that are informative about the developing event segmentation system. Infants' prediction of others' action goals is linked to their developing ability to perform that same goal-directed action (Ambrosini et al, 2013;Filippi & Woodward, 2016;Kanakogi & Itakura, 2011;Monroy, Gerson, & Hunnius, 2017b;Sommerville, Woodward, & Needham, 2005;van Elk, van Schie, Hunnius, Vesper, & Bekkering, 2008; but see Gampe, Keitel, & Daum, 2015). Further, as indexed by suppression or attenuation of EEG alpha rhythms over sensorimotor cortical regions of the brain, infants' motor systems are activated when making predictions about others' goal-directed actions; this motor response does not apply broadly to tracking movements and is instead specific to actions for which a likely goal can be anticipated (Southgate, Johnson, Karoui, & Csibra, 2010).…”

Statistical learning research: A critical review and possible new directions.

“…); face discrimination (e.g.,Altvater-Mackensen, Jessen, & Grossmann, 2016;Dotsch, Hassin, & Todorov, 2016); action prediction (e.g.,Monroy, Gerson, & Hunnius, 2017; Schuwerk, Sodian, & Paulus, 2017); orthographic regularities Hex & Tong (2016); and natural images (e.g.,Denison, Sheynin, & Silver, 2017).Our label of "Other" SL methods spans a range of experimental approaches. Here, again, we offer a few characteristic examples.…”