Object name learning and object perception: a deficit in late talkers.

Abstract

Two experiments examined the relation between early object name learning and the ability to represent objects by their abstract shapes. In Experiment 1, two-year-old children with productive vocabularies in the bottom 20th percentile--'late talkers'--were compared with (1) same-age children with larger vocabularies, and (2) younger children matched for productive vocabulary, on their ability to recognize named common objects. Object categories were represented two ways: by lifelike, perceptually rich toys, and by grey caricatures of those objects' abstract shapes. All 3 groups recognized lifelike objects equally well. Both typically-developing control groups were better than late talkers at recognizing shape caricatures of objects whose names they knew. In Experiment 2, late talkers and age-matched controls identified named objects represented by lifelike toys and by duplicates of those toys covered in grey textured paint. Age-matched controls knew more of the object names overall, but both they and the late talkers performed equally well on both kinds of test objects. Thus, late talkers had some difficulty in Experiment 1 recognizing objects from abstract shape cues, but no difficulty in Experiment 2 when the shape cues were realistic. The findings imply a relation between the growth of productive vocabulary and the emergence of the ability to represent object categories by abstract shape.