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

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.