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Abstract:
Abstract: Habituation paradigms are essential to the study of
cognitive and perceptual development. Habituation is commonly
thought to reflect stimulus encoding, thereby facilitating the
infant's ability to discriminate one stimulus from another. Yet,
little is known about what happens in the brain during habituation
or whether preferential looking to a novel stimulus reflects
differences in stimulus encoding or retrieval. To evaluate the
former hypothesis, event related potentials (ERPs) were recorded
using a 64-channel electrode cap while infants attended to a
repeatedly presented stimulus. Following familiarization, infants
were tested either immediately or after a 5-minute delay to see if
they showed preferential looking to a novel stimulus. Separate
grand means were calculated for each successive block of 20
familiarization trials to determine if 1) the evolution of the
morphology of the ERP (suggestive of different states of encoding)
or 2) the topography of the ERP (suggestive of different neural
generators) predicts novelty preference at test. Previous findings
from ERP studies of recognition memory in infants suggest that
progression from a late positive slow wave (thought to reflect
memory updating for a partially encoded stimulus) to a return to
baseline (thought to reflect a lack of further processing
indicative of a fully encoded stimulus) will predict novelty
preference at test. This prediction is currently being
evaluated.
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