Head Orientation Preference and Self-Touch Actions During Early Infancy.
The asymmetrical tonic neck reflex (ATNR) occurs when an infant turns the head to the side when lying supine and is present at birth and disappears around 3 months of age. Michel (1979; 1981) found that infants have a side preference for the ATNR, called the head orientation preference (HOP), which is related to hand preference. Michel's theory of handedness concatenation states that behaviors earlier in development will influence later appearing behaviors. Thus, a lateralized HOP will influence a later appearing preference for hand preference. Four infants were observed for supine head orientation preference (SHOP) and self-touch actions at 4-, 8-, and 12-week visits. All procedures from the three visits were video recorded for later analyses. SHOP procedure consisted of four 2-minute trials. For each trial, the infant's head was first held in a midline position for one minute and then released. Infant head orientation then was observed for one minute. For each trial, the videos were coded as right-turning or left-turning if the infant's head turned far enough to the right to cross the right nipple line. SHOP was determined using the formula [R-L/(R+L)1/2], where R and L indicated the number of trials in which an infant showed right or left head-turning. Following the SHOP procedure, the infant was observed for arm and hand movements for ten minutes while sitting in a semi-upright position. Self-touch actions were coded according to the arm which performed the action, and consisted of six behaviors: arm movements, wrist movement, finger wiggles, self-touch (contact upper body and contact lower body, and object contact. The descriptive results show that infants perform more actions with the right arm and hand than with the left arm and hand. Also, gross motor movements of the arm were the most frequently performed action, with finger movements also being performed frequently. Wrist movements and body and object contacts occurred infrequently. These observational findings support Michel's (1983) cascade theory of hand preference development, which states that early asymmetries in motor development can influence later appearing lateralized behaviors, via self-generated experiences. According to this theory, the higher frequency of right hand and arm actions observed in this sample will lead to a right bias in hand preference, which is observed in our society. These early lateralized skills should then, expand into hand-use preferences across a variety of manual skills.
Pattanakul, Duangporn; Gehm, Kevin; Cortina, Sarai; and Swinford, Danielle, "Head Orientation Preference and Self-Touch Actions During Early Infancy." (2018). University Research Symposium. 120.