Results of a study of 10- and 11- month-old infants support Piaget's hypothesis that practical, action-based knowledge during infancy is involved in achievement of spatial understanding and that the experience of self-initiated locomotion contributes to spatial development. (Author/NH)

The developmental pattern of concurrent synaptogenesis in rhesus monkeys is consistent with a straightforward model of relations between brain and cognitive development. Concurrent synaptogenesis is hypothesized to lay the primary cortical foundation for a series of developmental levels in middle infancy that have been empirically documented in…

Acquisition of the location aspect of American Sign Language signs was examined in nine young hearing infants and toddlers of deaf parents. Sign locations, overall, were produced with 83.5% accuracy. Highly contrasting locations were acquired first. Location played a central role in young children's early sign language acquisition. (Author/DB)

A quantifiable regimen of supplemental rotary vestibular stimulation was administered in a cross-over longitudinal design to 11 nonhandicapped and 10 Down's syndrome infants. Results indicated that supplementary rotary vestibular stimulation produced no measurable gain in motor ability. Greater gains were exhibited in the early phase of the study,…