Observed the reactions of 3.5-month-old infants looking at a carrot that should have but did not appear in a window after passing behind a screen. The results of this and several similar experiments indicated that 3.5-month-old infants are able to represent and reason about hidden objects. (BC)

The purpose of this study was to cross-sectionally and longitudinally examine the developmental process of search behavior in infancy. Subjects were 23 Japanese normal infants (11 males and 12 females) who were individually tested once a month from the age of six to 13 months in laboratory settings. Small toys and three white opaque cubic boxes…