Development of mental abilities: an investigation of the "Differentiation Hypothesis".
D000293:Adolescent; D000367:Age Factors; D002170:Canada; D002648:Child; D002657:Child Development; D003210:Concept Formation; D005260:Female; D006801:Humans; D007858:Learning; D008297:Male; D008433:Mathematics; D008606:Mental Processes; D010465:Perception; D013037:Spatial Behavior; D014705:Verbal Behavior