Patterns of interlimb coordination and lateral preference of spontaneous leg kicks were described for 8 normal human infants observed biweekly from 2 to 26 weeks of age. Newborn infants showed a high percentage of alternating movements, which were often supplanted by unilateral movements between 1 and 4 months. Simultaneous (in-phase) kicks matured later than alternating kicks. No consistent lateral preferences were detected. The developmental course was marked by variability and discontinuities within each infant. We propose that asynchronous and asymmetrical maturation of subcortical tracts and/or muscle strength could account for these behavioral shifts.
The present study investigated children's responses to a peer's childhood depression. Younger children in third and fourth grade and older children in fifth and sixth grade were exposed to one of four films. The four films portrayed a female peer who was either depressed or not depressed and who had experienced numerous recent life stresses or no recent life stress. Overall, children rated the depressed peers as less likeable and attractive, as engaging in fewer positive current and future behaviors, and as needing therapy more than a nondepressed peer. There was a tendency to rate the depressed peer with high life stress more positively than the depressed peer with low life stress; this tendency decreased with age. Girls rated all of the peers and especially the stressed peers more positively than did the boys. The results are discussed in terms of the implications of children's social interaction for the initiation or maintenance of childhood depression.
Newborn stepping is widely believed to be a "primitive reflex" whose disappearance signals cortical maturation. Observations of normal newborns showed that the number of steps was directly related to generalized behavioral arousal. In less highly distressed infants, those who were relatively heavier for their length stepped less. These results challenge the view that stepping is reflexively released by the upright posture and support the hypothesis that the movements disappear because infants' muscle strength may not be sufficient to lift their increasingly heavy legs.
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