Perceptual Development: Visually Guided Reaching

Eye-Hand Coordination in the Newborn

In the mid-1970s, researchers discovered that neo-nates can display a rudimentary form of eye-hand coordination. When provided with stable head and trunk support, newborn infants can extend their arm in a forward motion with the hand fully opened. Such full arm and hand extensions have been observed when objects are present in the infant visual field, but also when objects are absent from the infant visual field. These observations raised the question of the intentionality of this neo-nate response, but careful research from Claes von Hofsten indicated that visual attention influences early arm movements, suggesting that a nascent [Page 772]form of intentionality may already exist from birth. He found that when newborns were fixating the object in front of them, they tended to direct their arm closer to the object than when they were not fixating the object. Furthermore, when the hand came closer to the fixated object, newborns tended to slow down their movement. However, contact with the target almost never occurred. Because movement directedness and contact with the target are poorly controlled in the neonate, researchers called this response “prereaching” to indicate that it is prefunctional and precursory to the voluntary reaching response emerging a few months later.

By seven weeks of age, the rate of prereaching responses declines, and when prereaching occurs, the hand is no longer open, but fisted. This decline in response does not seem to be linked to a loss of interest in the task, as infants increase their rate of looking at the target during this time. It is possible that infant vision and head control, which improve dramatically by two months of age, temporarily inhibit the production of the prereaching response. Soon after, the rate of forward arm responses toward objects visually perceived increases steadily, and the hand begins to reopen gradually during the movement.

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