been reported previously. In one study, young adults were found to have significantly lower amplitude and stronger phase-locking than children in the 6-11 yr age range [101]. More recently Muller and colleagues [40] have demonstrated that age differences in phase locking in the delta and theta frequency bands was higher for under attended than unattended conditions using a simple auditory oddball task. And, additionally, Sander and colleagues [117] have reported that older adults show higher inter-trial phase stability shortly after stimulus onset as compared to children and younger adults using a working memory task. Early phase stability has been related to working memory performance in younger adults and high-functioning older adults [118]. Taken together these studies suggest that phase synchronization increases over development in human subjects over a range of frequencies and task requirements.
