Oral activity and exploration in 1–2‐month‐old infants*

Abstract

In order to study how information is processed through oral activity during infancy, its two main components, irregular mouthing (M) and non‐nutritive sucking (NNS), were investigated. It was hypothesized that if information is actually processed during M or NNS then it should subsequently be demonstrable in a recognition or a discrimination task.The first experiment tested this hypothesis through the use of cross‐modal transfer from oral touch to vision. Sixteen 1‐month‐old infants were first orally familiarized with a nubby or plain rubber nipple, and then tested for visual preference on corresponding shapes. Several results show that M rather than NNS involves information processing, but the amount of mouthing on such soft nipples was low and the links between M and subsequent preference were only marginally significant.A second experiment dealt with intra‐modal discrimination. Oral activity on hard nipples was video‐recorded in 24 2‐month‐old infants. During familiarization the amount of M decreased while the amount of NNS increased. The amount of M increased when a new oral shape was presented. Both experiments support the hypothesis that information about the stimulus is processed during mouthing rather than during NNS. Both approaches, cross‐modal and intra‐modal, are necessary to go beyond specific problems of transfer of information and adaptation of motor programmes.