title: Cross-sectional research, longitudinal theory, and a discriminative transfer ontogeny.
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D004193:Discrimination Learning; D006803:Human Development; D006801:Humans; D008137:Longitudinal Studies; D012193:Reversal Learning; D014796:Visual Perception