Telling Apart Motor Noise and Exploratory Behavior, in Early Development

Abstract

Infants’ minutes long babbling bouts or repetitive reaching for or mouthing of whatever they can get their hands on gives very much the impression of active exploration, a building block for early learning. But how can we tell apart active exploration from the activity of an immature motor system, attempting but failing to achieve goal directed behavior? I will focus here on evidence that infants increase motor activity and variability when faced with opportunities to gather new information (about their own bodies or the world) and propose this as a guiding principle for separating variability generated for exploration from noise. I will discuss mechanisms generating movement variability, and suggests that, in the various forms it takes, from deliberate hypothesis testing to increasing environmental variability, it could be exploited for learning. However, understanding how variability in motor acts contributes to early learning will require more in-depth investigations of both the nature of and the contextual modulation of this variability.

Exploring in Silence: Hearing and Deaf Infants Explore Objects Differently Before Cochlear Implantation

“…An earlier study of hearing infants (Gibson & Walker, ) temporarily limited access to visual input and found reduced variation in exploration; however, exploration duration was not reported. Therefore, in this study, reduced variation was predicted before cochlear implantation, in comparison with hearing infants, with increased variation in exploration following access to auditory feedback after cochlear implantation (e.g., Eppler, ; Gibson & Walker, ; Gliga, ). Evidence from comparing hearing and deaf infants is expected to support a role for auditory feedback in repetitive shaking and banging behaviors (see also Fagan, ), and to identify the behaviors less likely to vary with access to auditory feedback (e.g., inspection).…”

“…Interest in generating auditory feedback in repetition and vocalization has also been documented soon after cochlear implantation (Fagan, , ). Gliga () and Eppler () have argued, respectively, that increased motor activity and variability represent active learning, and that increased attention to auditory and visual object properties guides new actions. The increased variability (exploration types) and selective motor activity (shaking and banging) observed in this study, therefore, suggest periods of active learning and auditory attention with cochlear implants.…”

“…Although Palmer () did not report duration, she also noted 9‐month‐old hearing infants’ interest in shaking and banging objects (i.e., 2–16 times per object); infants shook sounding objects more frequently than silent objects, consistent with the behavior of hearing infants at Time 1 in this study. Post‐CI infants’ behavior with the noisy–silent object pairs suggests they too were beginning to differentiate, selectively act on, and perhaps test hypotheses about auditory affordances (Eppler, ; Gliga, ; Mash et al., ).…”

“…Efforts to explain exactly how infant behavior shapes learning and cognitive development are growing (Gliga, ; Marshall, ; Rakison & Woodward, ; Smith & Gasser, ; Tamis‐LeMonda, Kuchirko, & Tafuro, ; Woodward & Needham, ). In experimental tasks with hearing infants, for instance, active object manipulation experience influenced word learning and neurocognitive representations, understanding of intention (Gerson & Woodward, ; Kannass & Oakes, ; Thelen & Smith, ; Yee, Chrysikou, Hoffman, & Thompson‐Schill, ; Yu & Smith, ), and memory reactivation and generalization (Bahrick & Lickliter, ; Bauer, ; Hayne et al., ; Rovee‐Collier, Hartshorn, & DiRubbo, ).…”

The development of visually guided stepping

“…Variable error tells us how consistent steps are from one attempt to the next. Whilst variability tends to reduce with experience, it is an important feature of the learning process (Gliga 2018; Lee et al 2017), allowing exploration of possibilities for action. Like absolute error, when vision is occluded, variability increases for adult steps (Reynolds and Day 2005a).…”