P. Rochat et N. Goubet, DEVELOPMENT OF SITTING AND REACHING IN 5-MONTH-OLD TO 6-MONTH-OLD INFANTS, Infant behavior & development, 18(1), 1995, pp. 53-68
Three studies are reported, investigating changes in body engagement b
y 5- to 6-month-old infants as they reach for objects in the environme
nt. Infants are distinguished and compared based on their relative abi
lity to maintain a sitting posture without any external body support.
The first study demonstrates that manual reaching by sitter infants is
coordinated with forward leaning of the trunk, whereas reaching by no
nsitters is not. The second study demonstrates that nonsitter infants
provided with hip support also show signs of a coordination between re
aching of the hand and forward leaning of the trunk. The third study c
ompares nonsitter, nearsitter, and sitter infants as they reach for mu
ltiple objects spread across their prehensile space. Results demonstra
te expansion in the mapping of infants' prehensile space and hand use
as a function of self-sitting ability. The reported results are discus
sed as expressions of the interaction between the development of postu
ral, perceptual, and action systems in infancy.