Emily W. Bushnell - US grants

A number of studies are proposed for investigating how visual and tactual exploration interact with one another and with particular object properties during infancy. Interactions among these factors are considered to be determinants of infants' behavior on cross-modal tasks; furthermore, they delimit what infants can learn from inspecting objects biomodally. In two studies, whether infants direct their tactual explorations of objects according to the information available visually will be investigated. The manual behavior of 6- to 11-month-olds when certain tangible features can be seen will be compared to their behavior when the features cannot be seen. In a third study, the converse notion that infants may direct their visual explorations according to what they perceive by touch will be examined. Whether 9- and 12-month-olds adjust their posture in order to see an object feature that they can initially only feel will be observed. In another study, the hypothesis to be tested is that young infants may become so engrossed with the tactual exploration of objects that their sensitivity to visual properties of the objects is diminished. Six-month-olds' visual recognition memory for an object following bimodal familiarization will be compared to their tactual recognition memory for it, and to their visual recognition memory following only visual familiarization. In another study, it is hypothesized that infants' manual exploration may be elicited by visual information, but that once initiated, it is affected only by tactual information. Six-month-olds will be offered a familiar and a novel object, and their initial choice of which to touch as well as the extent of the consequent manual exploration will be noted. These variables will be compared across conditions in which novelty is specified only visually, only tactually, or in both modalities. In the final study, what sort of prior explorations may facilitate infants' recognition of objects across vision and touch will be investigated. The cross-modal matching performances of 6-month-olds who have seen the involved objects before, touched them before, or both will be compared to one another, and to the performance of infants for whom the objects are unfamiliar. The results of these studies will contribute to our understanding of the development of important relations between vision and touch and will advance our knowledge of how infants explore and ultimately come to understand the objects and events in their environment.

A number of studies are proposed for investigating how infants form "schemas" or mental representations of visual stimuli they encounter, and for identifying factors which may facilitate or impede the formation of such schemas. The overall approach of the proposed research is to identify systematic relationships between the nature of the visual information available (the input) and later memory performance (the output), so that inferences regarding the cognitive processes which mediate input and output may be drawn. In one series of studies, the memory performances (i.e., responses to novelty) of infants offered a "contrast" stimulus during familiarization will be compared to those of infants familiarized with pairs of identical stimuli. Whether the opportunity to compare the to-be-remembered stimulus with another during familiarization facilitates later recognition of its features will be determined, and the specific nature of such facilitation will be examined. Another study is designed to investigate the influence that the type of test procedure may have on infants' memory performance, separate from or in combination with the nature of the familiarization experience. The responses to novelty of infants tested with simultaneous presentations of familiar and novel stimuli will be compared to those of infants tested with successive presentations, to determine whether simultaneous test presentations afford an advantage for memory performance. In the final study proposed, the time course of stimulus processing will be investigated. Infants will be shown a series of brief presentations of paired stimuli; one of these will appear unchanged over the sequence of trials, while the other will be a different novel stimulus on each trial. The infants' relative preferences for the familiar and novel stimulus will be assessed on successive blocks of trials, so that the development and sequence of these preferences can be traced. The interactions of stimulus complexity and subject age with the time course of processing will also be investigated with this procedure. In all of the studies proposed, aspects of the infants' looking behavior will be monitored during familiarization trials as well as on test trials, so that we may identify distinct patterns of study during familiarization which might account for any observed differences in memory performance. The results of the proposed research should advance our knowledge of infant information processing, i.e., of what goes on "in the infant's head" as perceiving and remembering occur.