Efeito da visibilidade dos braços sobre a preferência manual e controle motor na ação de alcançar em bebês

Abstract

This study aimed to evaluate the effect of visual occlusion of the preferred arm on its frequency of use and kinematics in spontaneous reaching of static objects in 5-month-old infants. Participated in this study 30 infants, with half of them submitted to visual occlusion of the preferred arm and the other half having full vision while reaching a toy. A possible cumulative effect of visual occlusion was assessed through increasing periods in which the preferred arm was not visible by the infant. Analysis of manual preference indicated that occlusion of the preferred arm led to increased use of the contralateral arm for reaching, an effect more evident in infants showing weak manual preference. No effect of cumulative occlusion was detected, with similar indices of manual preference across the periods of occlusion. Results from kinematic analysis revealed straighter movements to the target when visually oriented. These results suggest that visual information can modulate manual preference and guide reaching control.