The ability to coordinate vision with fine motor skills.
Hand-eye coordination begins developing in infancy. Although it is an instinctive developmental achievement that cannot be taught, parents can hasten its progress by providing their children with stimulating toys and other objects that will encourage them to practice reaching out for things and grasping them.
Until the age of eight weeks, infants are too nearsighted to see objects at distances farther than about 8 in. (20 cm) from their faces, and they have not yet discovered their hands, which are kept fisted throughout this period. By the age of two to two-and-a-half months, the eyes focus much better, and babies can follow a moving object with their gaze, even turning their heads to keep sight of it longer. However, when a child this age drops an object, she will try to find it by feeling rather than looking for it, and although she plays with her hands, she does it without looking at them.
By three months, most infants will have made an important hand-eye connection; they can deliberately bring their hands into their field of vision. By now they are watching their hands when they play with them. They also swipe at objects within their view, a repetitive activity that provides practice in estimating distance and controlling the hands. Attempts to grab onto things (which usually fail) consist of a series of tries, with the child looking at the object and then at his hand, moving his hand closer to it, and then resighting the object and trying again.
At the age of four or five months, hand-eye coordination is developed sufficiently for an infant to manipulate toys, and she will begin to seek them out. By the age of six months, she can focus on objects at a distance and consistently follow them with her eyes. At this point, the infant can sight an object and reach for it without repeatedly looking at her hand. She senses where her hand is and can lead it straight to the object, keeping her eyes on the object the entire time. By the final months of her first year, an infant can shift her gaze between objects held in both hands and compare them to each other.
The toddler stage brings further progress in handeye coordination, resulting in the control necessary to manipulate objects with increasing sophistication. The ability to sight and grasp objects accurately improves dramatically with the acquisition of the “pincer grasp.” This ability to grasp objects between the thumb and forefinger develops between the ages of 12 and 15 months. Around the same time, children begin stacking objects on top of each other. Most can stack two blocks by the age of 15 months and three by the age of 18 months. At this age they also begin emptying, gathering, and nesting objects, or placing one inside another. Toddlers can also draw horizontal and vertical pencil lines and circular scribbles, twist dials, push levers, pull strings, pound pegs, string large beads, put a key in a lock, and turn book pages. Eventually, they are able to stack as many as six blocks, unwrap small objects, manipulate snap toys, and play with clay. Between the ages of 15 and 23 months there is significant improvement in feeding skills, such as using a spoon and a cup.
Hand-eye coordination improves through middle childhood, with advances in speed, timing, and coordination. By the age of nine, the eyes and hands are well differentiated, that is, each can be used independently of the other, and improved finger differentiation is evident as well. Nine-year-olds can use carpentry and garden tools with reasonable skill and complete simple sewing projects.
See also Fine motor skills .