Habituation changes in early infancy: Longitudinal measures from birth to 6 months

Abstract

A visual habituation experiment was conducted on 36 new-born infants who were followed up at 2, 4 and 6 months of age. There was no evidence for individual stability on habituation measures across age. However, a significant trend was identified in five measures commonly used to characterize habituation: (1) mean duration of looking time during habituation; (2) total duration of looking time during habituation; (3) longest look during habituation; (4) mean of first two looks; and (5) the length of the first look. On all measures, 2-month-olds exhibited the longest durations compared with the new-borns and the older infants. This finding is consistent with other reports of prolonged visual gaze around 1–2 months of age. However, relatively brisker shifts of visual attention in the same infants during the new-born period indicates that this behaviour exhibits a U-shaped function over the early months of life.