[Categorization in infancy: differentiation of global object classes]

Two studies tested whether preverbal children distinguish global categories (animal and furniture) on a conceptual basis. A total of 59 eleven-month-olds solved an object examination task. During habituation, infants freely explored different natural-looking toy models from the same category. In Study 1, the same series of four different examplars was presented twice. In Study 2, ten different exemplares were presented. In both cases, a significant habituation effect could be observed. When a perceptually new object of the same category was presented on the first test trial after habituation, a significant increase in examination time from the last habituation trial to the first test trial could be observed in Study 1. When a new object of the contrasting category was presented on the second test trial, examination times increased significantly from the first to the second test trial in both studies. These results support earlier findings suggesting that preverbal infants are able to distinguish global categories on a conceptual basis.