The aim of this systematic literature review was to examine and discuss studies that investigated reaching in preterm infants during the first year of life. Databases were searched using keywords such as reaching, grasping, preterm, and premature, in addition to specific terms from the Medical Subject Headings (MeSH) (motor skills, infant, movement, premature birth, hands) regardless of year of publication. One hundred thirty-five studies were identified, 9 of which were selected. The results showed that preterm infants adopt strategies (bimanual reaches and reaches with less rectilinear trajectories toward an object in motion, reaches with semi-open and open hand, reaches at lower speeds, with increased movement units, and variable postural muscle activity) compared with full-term infants. However, the results on how intrinsic factors (e.g., prematurity) and extrinsic factors (e.g., body position, physical properties of the object) influence early reaching are still limited.
Elaine Leonezi Guimarães, Andréa Baraldi Cunha, Daniele de Almeida Soares and Eloisa Tudella
Andréa Baraldi Cunha, Daniele A. Soares, Alyne Montero Ferro and Eloisa Tudella
The objectives of this study were to verify the influence of a short-duration training session on proximal and distal adjustments at the onset of goal-directed reaching and to verify whether these adjustments change in specificity with the body position trained. Twenty-four infants aged 3–4 months were assessed in supine and reclined during pre and posttraining conditions. During the interval (4 min), 8 infants received reaching training in supine, 8 infants received reaching training in reclined, and 8 infants received no training. The frequencies of reaches, unimanual reaches and reaches with semiopen and oblique hand increased in the posttraining condition for all infants except control infants. Infants trained in the reclined position increased the frequencies of variables in the reclined position. Infants trained in the supine position increased the frequencies of variables in both positions. Few minutes of reaching training are effective to facilitate reaching behavior in infants at the onset of reaching. The effects are specific to the body position trained. As the training in supine requires higher torque to initiate reaching movements, it is more effective to facilitate reaches in both supine and reclined positions.