Two experiments replicated Flavell et al.'s (1978) finding that 2.5-year-olds can hide an object behind a screen but cannot achieve the same result placing the screen in front. Move-screen performance related to judgment of what a person in a picture was looking at. Move-object task remained easier than the move-screen task even with an…

Kim (1985) found that both English-speaking and Korean-speaking children find true negative sentences more difficult to verify than false negative sentences. A closer examination of the findings reveals that the difficulty is greater among Korean-speaking children. (Author/RH)

Replies to Akiyama's critique, pointing out areas of agreement between the Kim and Akiyama studies and areas of disagreement. Concludes that, contrary to Akiyama's argument, the Kim (1985) data would not directly challenge the cognition primacy hypothesis in any serious manner. (RH)

Three experiments explored determinants of two-year olds' perseverative errors in a search task. Found that active search, even in the absence of observation, produced perseveration on post-switch trails, but mere observation did not. Results indicated that active search is required to elicit perseveration, which points to failures of response…

Three experiments assessed the claim that preschoolers override form class cues in the interest of honoring word- meaning assumptions when acquiring new labels. Results demonstrated that children respected the form class cues when these cues and word-meaning assumptions suggested conflicting interpretations. It was suggested that past findings…

Examined the relationship between 6- to 8-year olds' conceptual understanding of additive composition, commutativity, and associativity principles and addition problem-solving procedures. Results revealed that conceptual understanding was related to using order-indifferent, decomposition, and retrieval strategies and speed and accuracy in solving…

Provided 2- and 2.5-year-olds with partial visual information about a ball's path as it moved toward a hiding place. Found that both age groups were equally proficient at tracking the ball as it rolled behind a transparent screen with 4 opaque doors, but 2.5-year-olds were more likely to reach to the correct door when asked to find the ball.…

Investigated whether Brazilian 4-year-olds held essentialist beliefs about animal categories. Found that middle class and poor children were equally likely to interpret labels as referring to mutually exclusive animal categories, and more likely to accept a common label for animals sharing internal properties than superficial properties,…

Three experiments tested 21- and 27-month olds' ability to construct a path to a mentally re-presented goal. After seeing the goal-state configuration of problems, both age groups evinced planning. Demonstration of initial solution step was less effective than goal-state exposure. Even with specification of a greater proportion of the goal path,…

Three experiments examined the early development of three- to five-year-old children's analysis of spatial patterns. Found that the youngest children segmented out simple, well-formed, spatially independent parts and used simple relational structures to bind these parts together, whereas older children constructed forms that included increasingly…

Two studies examined whether object names and functions act as cues to categories for infants. Findings indicated that both 14- and 18-month-olds were more likely to select the category match after being shown a novel category exemplar with its function than when given no additional cues. Only at 18 months did naming the objects enhance…

Investigated 3-year-olds' understanding of the appearance-reality distinction using verbal response and nonverbal response paradigms in 4 experiments. Found that about 30 percent of children were correct in verbal paradigm; over 90 percent of same children were correct in nonverbal paradigm. Participating in the verbal paradigm impeded children's…

Two studies examined preschoolers' appreciation of how mental states arise. Findings suggest that 3- and 5-year-olds better understood perception-generated beliefs and attitude-generated desires than physiology-generated desires. Four- and 5-year-olds better understood the effects of quantity of experience than of time of experience on…

Twelve- and 18-month-olds played with 2 adults and 2 new toys. For a third toy, one adult left the room while the child and other adult played with it. This adult returned, looked at the 3 toys, expressed excitement, and asked "Can you give it to me?" Infants at both ages were able to do so, suggesting that 1-year-olds understand other persons as…

Three experiments tested 3- and 4-year-olds' use of abstract principles to classify and label objects by shape or function. Findings indicated that 4-year-olds readily adopted either rule when instructed to match objects by shape or function, but 3-year-olds followed only the shape rule. Without a rule, 4-year-olds tended to match by shape unless…