Multisensory exploration and object individuation in infancy.

Abstract

Recent research indicates that by 4.5 months, infants use shape and size information as the basis for individuating objects but that it is not until 11.5 months that they use color information for this purpose. The present experiments investigated the extent to which infants' sensitivity to color information could be increased through select experiences. Five experiments were conducted with 10.5-and 9.5-month-olds. The results revealed that multimodal (visual and tactile), but not unimodal (visual only), exploration of the objects prior to the individuation task increased 10.5-month-olds' sensitivity to color differences. These results suggest that multisensory experience with objects facilitates infants' use of color information when individuating objects. In contrast, 9.5-month-olds did not benefit from the multisensory procedure; possible explanations for this finding are explored. Together, these results reveal how an everyday experience-combined visual and tactile exploration of objects-can promote infants' use of color information as the basis for individuating objects. More broadly, these results shed light on the nature of infants' object representations and the cognitive mechanisms that support infants' changing sensitivity to color differences.

Cortical activation to object shape and speed of motion during the first year

“…Motion artifacts were not removed when they occurred post-event, as these do not affect data processing and would result in significant data loss (e.g., infants are more active during the baseline event). This is the same approach used in previous studies (Wilcox et al, 2005; Wilcox et al, 2007; Wilcox et al, 2010; Wilcox et al, 2012) and these studies have demonstrated that 10 s is sufficient for the hemodynamic response to return to baseline in this experimental context. In short, the apparent increase in the optical signal (or failure to decrease) during baseline is not due to a delay in recovery but to unfiltered motion.…”

“…In the developmental sciences, there is a substantial body of research demonstrating an intimate link between perception, action, and cognition in the developing infant (e.g., Campos et al, 2000; Corbetta, 2009; Sommerville & Woodward, 2010). One theme that runs through much of this work is the importance of coordinated visual and manual exploration of objects on infants’ learning about the physical properties of those objects (Möhring & Frick, 2013; Needham, 2002; Soska, Adolph, & Johnson, 2010; Wilcox, Woods, Chapa, & McCurry, 2007). Some infant researchers (Kaufman, Mareschal & Johnson, 2003; Mareschal & Johnson, 2003) have hypothesized that when infants are visually presented with objects that could potentially be acted upon (such as 3D objects moving across a near-by stage in real space and time), the processing of object properties that could influence action on those objects, such as shape, will activate dorsal areas in the cortex.…”

“…First, infants 3 to 5 months of age, who use shape but not color information to individuate objects (Wilcox, 1999), showed activation in the anterior temporal cortex when viewing the shape difference but not the color difference test event (see also Wilcox et al, 2010). It is not until 11 to 12 months, when infants first individuate-by-color (Wilcox, 1999; Wilcox et al, 2007), that infants showed activation in the anterior temporal cortex when viewing the different-color event. Neither age group showed activation in anterior temporal cortex when viewing the control (green ball-green ball) test event, an event that infants interpret as involving a single object that moves back and forth behind the screen (Wilcox, 1999).…”

Memory load affects object individuation in 18-month-old infants

“…For these older infants, some additional evidence suggests that infants used the featural differences between objects to set up contrasting kind representations and that these kind representations are critical to individuation (Bonatti, Frot, Zangl, & Mehler, 2002;Xu, Carey, & Quint, 2004;Xu, Cote, & Baker, 2005). However, when the task is made simpler (e.g., Wilcox & Baillargeon, 1998b;Wilcox & Chapa, 2002;Wilcox & Schweinle, 2002) or when given additional experience with objects' features (Wilcox, Woods, & Chapa, 2008;Wilcox, Woods, Chapa, & McCurry, 2007), infants much younger than 12 months also appear to use featural cues to individuate and can do so with objects that do not clearly contrast in kind membership (e.g., ball vs. box). Taken together, these studies of infants' object individuation abilities have revealed which object features infants can use for individuation as well as which experimental paradigms make individuation more or less difficult (e.g., Bonatti et al, 2002;Krojgaard, 2007;Surian & Caldi, 2010;Wilcox & Baillargeon, 1998a, 1998bXu et al, 2005).…”

Object Function Facilitates Infants' Object Individuation in a Manual Search Task

“…These studies were conducted in the cognitively lessdemanding event-monitoring design developed by Wilcox andBaillargeon (1998a, 1998b). In one study Wilcox, Woods, Chapa, and McCurry (2007) found that letting 10.5-month-olds have access to multisensory (tactile and visual) exploration of red and green balls prior to an individuation test enabled the infants to individuate the balls visually based on color differences in the test (whereas preexposure to visual exploration only did not have this effect). In another object individuation study by Wilcox and Chapa (2004), infants first saw small events in which object color predicted the functional use of a spoon-like object (either pounding or pouring).…”