Neuropsychological correlates of school achievement in young children: longitudinal findings with a construct valid perceptual processing instrument.

A form discrimination and a form copying test developed using constructs from basic research in form perception were administered to first-, second-, and third-grade children. Relationships between performance on these tests and achievement scores were investigated both concurrently and over a 2-year follow-up period. These analyses demonstrated the relevance of visual-perceptual factors to academic achievement at all grade levels. Additionally, the pattern of relationships obtained substantiated the existence of age trends in the relationship between perceptual processing factors and academic achievement as has been hypothesized in the child neuropsychology literature.

The effect of familial sinistrality on perceptual learning.

Perceptual learning as measured by adaptation to prismatically displaced vision was contrasted in groups of familial sinistral (FS) and familial dextral (FD), strongly right-handed adult females. The FS group exhibited significantly larger target pointing and eye positioning adjustments than the FD group. Further, only the FS group showed transfer of training from the hand used during prism viewing to the unobserved one.

Individual differences in the visual component of prism adaptation.

The centrality of individual differences in the visual component of perceptual adaptation was examined in a massed-practice-terminal-exposure, prism-viewing paradigm. With positive (adaptive) adjustments in the judgment of the visual straight-ahead, target-pointing aftereffects were found to be equivalent to the sum of the visual and proprioceptive (head-arm) aftereffects. For subjects showing negative visual adjustments to prism exposure, the target-pointing aftereffect was not significantly different from the change in proprioception alone. Implications of these findings for hypotheses concerning the process of perceptual adaptation are discussed.