TRANSITIONS IN CONCEPT-ACQUISITION - USING THE HAND TO READ THE MIND

Thoughts conveyed through gesture often differ from thoughts conveyed through speech. In this article, a model of the sources and consequenc es of such gesture-speech mismatches and their role during transitiona l periods in the acquisition of concepts is proposed. The model makes 2 major claims: (a) The transitional state is the source of gesture-sp eech mismatch. In gesture-speech mismatch, 2 beliefs are simultaneousl y expressed on the same problem-one in gesture and another in speech. This simultaneous activation of multiple beliefs characterizes the tra nsitional knowledge state and creates gesture-speech mismatch. (b) Ges ture-speech mismatch signals to the social world that a child is in a transitional state and is ready to learn. The child's spontaneous gest ures index the zone of proximal development, thus providing a mechanis m by which adults can calibrate their input to that child's level of u nderstanding.