From the reaching behavior at 5 months of age to hand preference at preschool age.
The aim of the study was to examine the reaching behavior at the age of 5 months, and to determine whether and to what extent there is a relationship between hand use at this age and manual laterality at preschool age. 20 participants (13 girls and 7 boys) were investigated on two occasions: At the age of 5 months we assessed the hand use for reaching for four different objects placed at the infant's body midline or in their right or left hemispaces, respectively. At the age of 5 years and 7 months, we assessed the hand use for 22 motor tasks. The handedness status was calculated in order to reflect the sinistrality-dextrality continuum. All but one infant were unimanual reachers at 5 months of age. Preferential reaching was space dependent rather than object dependent at this stage. Children reaching for objects in the right hemispace predominantly with their right hand showed a significantly greater right hand laterality at late preschool age than children who at the age of 5 months had shown inconsistent hand use (p < .05). Children who at the age of 5 months had reached for objects in the left hemispace with their left hand proved to be less lateralized in their right hand use approximately 5 years later (p < .05).
Marschik
Peter B
PB
Institute of Physiology, Center for Physiological Medicine, Medical University of Graz, Harrachgasse 21, 8010 Graz, Austria.
Einspieler
Christa
C
Strohmeier
Andrea
A
Plienegger
Johann
J
Garzarolli
Bettina
B
Prechtl
Heinz F R
HF
D002657:Child Development; D002675:Child, Preschool; D002755:Choice Behavior; D005260:Female; D007839:Functional Laterality; D006801:Humans; D007223:Infant; D008297:Male; D009949:Orientation; D002666:Psychology, Child; D011597:Psychomotor Performance