ERIC Number: ED344679
Record Type: RIE
Publication Date: 1992-Mar
Reference Count: N/A
Origins of Handedness in Human Infants.
Butterworth, George; Hopkins, Brian
This paper reviews the literature on handedness in infants and reaching behavior in neonates and speculates on evolutionary reasons for the development of handedness. Modern studies have reliably detected handedness from the second half of the first year of life. One study found a preference for the right hand in unimanual tasks at 6.7 months. Other studies have shown that contralateral reaching occurs 3 months sooner for the right hand than the left. Several studies of neonatal reaching behavior have shown that: (1) babies between 3 and 8 days old make predominantly right arm reaches to a visual target; (2) the right arm is spontaneously more active than the left in newborns; and (3) by 3 months of age, infants show greater persistence in grasping a rattle with the right hand than the left. Other studies have determined a correlation between neonatal head orientation preference, which begins to develop during the fetal stage, and hand preference. Evolutionary speculations on handedness concern the preference for cradling infants on the left arm; the fact that the infant must turn its head to pass through the birth canal; and the evidence from stone tools that Homo Erectus was predominantly right-handed. A list of 40 references is provided. (BC)
Publication Type: Information Analyses; Speeches/Meeting Papers
Education Level: N/A
Authoring Institution: N/A
Identifiers: Hand Function; Head Movements; Reaching Behavior
Note: Paper presented at a Meeting of the Spastics Society (Wallingford, Oxfordshire, England, United Kingdom, March 25-26, 1992).