Detecting Transparent Barriers: Clear Evidence Against the Means‐End Deficit Account of Search Failures

Abstract

The standard explanation of infants' search failures with hidden objects, despite an apparent sensitivity to them, is a deficit in the means-end skill for retrieving objects from occluders. Studies equating means-end demands for retrieving toys from transparent and opaque barriers challenge this account by showing that infants succeed more with visible objects. However, they suffer from a critical limitation: Infants may retrieve visible objects without noticing the transparent barriers in front of them. We addressed this concern by requiring infants to notice a barrier to retrieve a toy and specifically to pull down a rotating screen to retrieve a toy from behind it. Seven-month-olds used this means-end skill more often with a transparent barrier than an opaque one. Thus, neither a means-end deficit nor an ability to ignore transparent barriers fully accounts for search failures. Relations to other findings challenging the means-end deficit account and implications for approaches to studying cognitive development are discussed.

Décalage in infants' knowledge about occlusion and containment events: Converging evidence from action tasks

“…The processing-load account can explain a wide array of findings in search, support, and other action tasks: for example, why infants are more likely to retrieve an object hidden behind a barrier when they can do so by reaching as opposed to crawling around the barrier (Lockman, 1984); why infants are more likely to search for an object hidden by turning off the room lights than for an object hidden under a cloth (Goubet & Clifton, 1998;Hood & Willatts, 1986); why infants are more likely to find an object hidden in one of two locations when searching visually than manually (Hofstadter & Reznick, 1996); why infants are more likely to remove a transparent than an opaque curtain or screen to retrieve an object behind it (Shinskey, Bogartz, & Poirier, 2000;Shinskey & Munakata, 2001); and why infants are more likely to retrieve an object on the far end of a support when they believe the object is attached to, rather than separate from, the support (Aguiar & Baillargeon, 2000). In each case, success is more likely when overall task demands are reduced, either because the actions are easier to plan and execute, or because the objects are easier to represent.…”

Can infants be “taught” to attend to a new physical variable in an event category? The case of height in covering events

“…Second, more generally, such findings support the view that the same physical knowledge underlies infants' responses in violation-of-expectation and action tasks (e.g., Baillargeon et al, in press;Hespos & Baillargeon, 2006, 2007Wang & Kohne, in press). Of course, infants sometimes fail to reveal in action tasks knowledge that they readily reveal in violation-of-expectation tasks (e.g., Ahmed & Ruffman, 1998;Diamond & Lee, 2000;Piaget, 1954;Shinskey & Munakata, 2001;Vishton, Ware, & Badger, 2005). When such discrepancies arise, one of at least three explanations may apply: (1) infants may have difficulty planning the necessary actions (e.g., Baillargeon, Graber, DeVos, & Black, 1990;Willatts, 1997); (2) poor motor control may make it difficult for infants to execute the necessary actions (e.g., Diamond & Gilbert, 1989;Diamond & Lee, 2000); and (3) infants may be able to plan and execute the necessary actions, but may fail to do so because the total demands of the task (which depend on the difficulty of both the physical reasoning and the actions involved) overwhelm their limited information-processing resources (e.g., Boudreau & Bushnell, 2000;Keen & Berthier, 2004).…”

Perceiving expressions of emotion: What evidence could bear on questions about perceptual experience of mental states?

“…And, third, the conjecture suggests an elegant way of making sense of some otherwise puzzling discrepancies between tests of infants' abilities to represent unperceived objects using different measures (e.g. Shinskey & Munakata 2001;Moore & Meltzoff 2010;Hood et al 2000Hood et al , 2003.…”