Abstract
In infants, the posterior alpha EEG rhythm has been found to index visual attention in infants (Michel et al., 2015; Xie et al., 2018). Alpha peak frequency increases from infancy into childhood and adulthood, however, the trajectory and underlying mechanisms responsible for have been largely unexplored. In the current study, we explored the developmental trajectories of alpha peak frequency across the first year of life. Six-month-old (n=49), 9-month-old (n=33), and 12-month-old (n=31) infants completed a short, sustained attention task in which novel computer-generated objects and female faces appeared at the top (in the middle) of the screen and then moved, or floated, to the bottom of the screen and then out of view. Peak alpha frequency was calculated using the center of gravity (CoG). Results indicated that in the face condition, peak alpha frequency significantly increased from 6 (M= 6.617 Hz, SD= 0.091) to 9 (M= 6.686 Hz, SD= 0.096) to 12 (M= 6.739 Hz, SD= 0.109) months of age in the middle occipital, the right and left frontal, and the right and left central regions. In the object condition, peak alpha frequency significantly increased from 6 (M= 6.604 Hz, SD= 0.084) to 9 (M= 6.683 Hz, SD= 0.094) to 12 (M= 6.722 Hz, SD= 0.135) months of age in the middle occipital, the right and left frontal, and the left (and not right) central regions. This investigation is the first to use this task and examine the developmental trajectory of peak alpha frequency across the first year of life and suggests that neural processes underlying alpha oscillatory activity develop slowly over time and the topography of the response is sensitive to stimulus type (faces; objects).