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Previous research has shown that 2-year-old children are not able to use information from television (the location of a toy in a room) to solve a problem (finding the toy). One explanation for this result is that 2-year-olds are sophisticated enough to understand that what they see on television does not affect their immediate surroundings (the reality hypothesis). Another explanation is that difficulties with symbolic media led to their failure (the symbolic hypothesis). A third explanation is that the visual perceptual quality of television is too weak for the children to use to update their representations of the location of the toy in the room (the perceptual hypothesis). The first purpose of this study was to replicate the finding that 2-year-olds are unable to find a toy in a room if they see the toy hidden on television, but are able to find it if they watch through a window as a toy is hidden. This finding was replicated, although the result was not significant. It was also found that 2-year-olds performed significantly above chance on the first trial when they watched the hiding event on television. The second purpose of this study was to determine whether the reality hypothesis was supported when visual symbolic and visual perceptual issues were accounted for. Two-year-old children listened to an experimenter, either live or on television, tell them where to find a toy in a room. This eliminated any potential visual symbolic or perceptual problems. Two-year-olds did significantly better when the live experimenter told them where to find the toy than they did when they heard the experimenter on television, supporting the reality hypothesis. However, first trial effects indicate that the reality hypothesis cannot completely account for children's failure to use televised information to find a toy in a room. A new explanation for these results is put forth that is based on the idea that 2-year-olds can and will use information presented on television to solve a problem as long as that information does not conflict with information that they received in “reality”.

The appearance-reality distinction refers to the understanding that objects can have misleading appearances that contradict reality. Traditionally, studies investigating children's ability to make this distinction have used a verbal-based task that requires children to answer two questions regarding the appearance and reality of a target object whose appearance has been altered. In general, these studies have found that children are not successful in this task until 4–5 years of age. The purpose of the current study was to investigate three different hypotheses regarding why 3-year-olds fail the traditional verbal-based task in order to determine whether their poor performance truly represents an inability to distinguish appearance from reality. In Experiment 1, the hypothesis that 3-year-olds fail the traditional task simply because they are unfamiliar with the property-distorting devices typically used to alter the appearances of target objects, rather than an inability to distinguish appearance from reality, was examined. Experiments 1 and 2 also examined the hypothesis that 3-year-olds' failure in this task may be due to an inability to assign conflicting, dual representations to a single object. Finally, the role of the language used in making the appearance-reality distinction also was examined in both experiments. In this case, the hypothesis that 3-year-olds may be able to distinguish appearances from reality in an action-based, but not verbal-based task, was evaluated. In Experiment 1, all of this was done using a property-distorting device typically used in traditional appearance-reality studies, whereas a completely new method for altering the appearances of objects was used in Experiment 2. No supporting evidence for the familiarity or dual representation hypotheses was found in either experiment, however, children in both experiments performed better on an action-based task than on two verbal-based tasks. Children went from answering the traditional appearance-reality questions on the basis of misleading perceptual information to overriding this misleading information in an action-based task. Together, these results provide evidence that 3-year-olds have some competence in distinguishing appearances from reality that is masked by the language demands of the traditional verbal-based task.

Studies in adults have shown that the role of the postural system during most motor behaviors is more complex than just merely minimizing positional deviations away from a stable equilibrium point. Rather, the postural system appears to be highly coordinated and integrated with other suprapostural behaviors. How the integration and coordination between the postural system and other suprapostural behaviors develops has not been extensively examined. In this project the developmental integration and coordination between posture and manual control was studied in children (7- and 10-years of age) and compared with healthy college aged adults. All subjects were required to fit a block through an opening as precision, postural and visual constraints were manipulated. Trunk and arm kinematics and center of pressure data were obtained. Compared to adults children adopt different postural strategies during the fitting task (Chapter 4), appear less able to modulate postural stability as precision demands increase (Chapter 5), and exhibit less ability to use functionally exploit postural fluctuations (Chapter 6). Taken together, results suggest that even by 10-years of age, the postural system is not integrated with the manual control system at adult like levels.