Do 5-month-old infants see humans as material objects? - Research discussion and experiments

Aug 29, 2026

Uploaded by Levi

5-month-old infants’ expectations about objects emphasize solidity, cohesion, and continuity of motion along connected paths. This study tests whether infants also treat humans as material objects subject to these same constraints. Results show that infants apply the continuity principle to inanimate blocks but not to people, indicating two distinct modes of construal: one for inanimate objects and another for humans. The paper reports two experiments using habituation and violation-like looking-time measures.

LanguageEnglish

CategoryResearch & Report

FormatPDF

Pages9

Reading Time23 min

AccessFree to download

Discussion

Research question

Methods and experiments

Experiment 1: Inanimate objects

Experiment 2: Human actresses

Cognition 94 (2004) 95–103 [www.elsevier.com/locate/COGNIT](www.elsevier.com/locate/COGNIT) Discussion Do 5-month-old infants see humans as material objects? Valerie A. Kuhlmeier*, Paul Bloom, Karen Wynn Yale University, 2 Hillhouse Avenue, New Haven, CT 06520, USA Received 10 November 2003; accepted 20 February 2004 Abstract Infants expect objects to be solid and cohesive, and to move on continuous paths through space. In this study, we examine whether infants understand that human beings are material objects, subject to these same principles. We report that 5-month-old infants apply the constraint of continuous motion to inanimate blocks, but not to people. This suggests that young infants have two separate modes of construal: one for inanimate objects and another for humans. q 2004 Elsevier B.V. All rights reserved. Keywords: Inanimate objects; Animates; Constraints Infants have appropriate expectations regarding the nature of objects (Aguiar & Baillargeon, 1999; Baillargeon, Spelke, & Wasserman, 1985; Leslie, 1982) . As early as 4 months of age, infants are sensitive to violations ofthe constraints of object physics such as cohesion (objects move as bounded wholes) (Spelke & Van de Walle, 1993), solidity (two objects do not occupy the same space at the same time) (Baillargeon, Needham, & DeVos, 1992; Spelke, Breinlinger, Macomber, & Jacobson, 1992), and continuity (objects move on connected paths) (Spelke, Kestenbaum, Simons, & Wein, 1995) . It is also the case that infants distinguish between inanimate objects and animates, namely humans, in important ways. For example, they recognize that humans are self-propelled while inanimate objects move only after contact with another object (Poulin-Dubois, Lapage, & Ferland, 1996; Rakison & Poulin-Dubois, 2001; Spelke, Phillips, & Woodward, 1995) . However, do infants recognize that, in some cases, the principles they readily apply to inanimate objects also apply to humans? In other words, do they understand that people are * Corresponding author. Tel.: þ1-203-436-1414 . E-mail address: [valerie.kuhlmeier@yale.edu](valerie.kuhlmeier@yale.edu) (V.A. Kuhlmeier). 0022-2860/$ -see front matter q 2004 Elsevier B.V. All rights reserved. doi:10.1016/j.cognition.2004.02.007 96 V.A. Kuhlmeier et al. / Cognition 94 (2004) 95–103 objects that are subject to physical laws such as cohesion, solidity, and continuity? If they do, it would imply an understanding of the duality of humans: animate objects engaging in self-initiated action, yet fundamentally material objects. Here, we examine this question by using the test case of the continuity principle. We tested 5-month-olds’ application of this principle to inanimate objects and humans, using a procedure modeled after Spelke, Kestenbaum, et al. (1995) . In that study, infants were familiarized to an object moving across a stage that contained two occluding screens. Infants who saw the object slide behind the ﬁrst screen, then “reappear” from behind the second screen without having traversed the intermediary space, looked longer at a subsequent test display of one object than at a display of two identical objects, implying that the former was more novel or surprising than the latter. That is, the infants recognized the discontinuity of motion in the original presentation and, since a single object cannot move in such a manner, inferred the presence of two objects. Consistent with this interpretation is the fact that infants in the same study who were familiarized to an object moving in a continuous manner (behind one screen, through the intermediary space, then behind the second screen and out again) showed preferential looking to the test display of two objects (Spelke, Kestenbaum, et al.) . In the present two experiments, we test infants ina similar manner using analogous, videotaped scenes depicting either inanimate objects (Experiment 1) or human actresses (Experiment 2) . 1. Experiment 1 1.1. Method

FAQs

What main question does the study address?

Whether 5-month-old infants understand that humans are material objects and should follow the same physical constraints as inanimate objects, especially continuity of motion.

What do the results suggest about infants’ understanding of humans?

Infants apply continuous-motion expectations to inanimate blocks but not to people, suggesting separate construal modes for inanimate objects versus humans.

How were the experiments designed to test this idea?

The study uses a habituation and looking-time procedure with videotaped scenes: one resembling continuous motion for inanimate objects (Experiment 1) and another using human actresses (Experiment 2).

Aug 29, 2026

Uploaded by Levi