2005). Regarding measures of PFC systems, there is some evidence from adult studies of frontal EEG asymmetry that when participants are asked to generate an emotion state, females show a right-frontal EEG bias while males do not; however, these effects may be fairly task specific (Davidson et al., 1976). Under resting conditions, on the other hand, sex differences are not typically found for adults (Davidson et al., 1976; Sutton and Davidson, 2000) or infants and young children (Buss et al., 2003; Fox et al., 1995). Given this inconsistent pattern of findings, possible sex/gender effects are worth considering; it is likely that ELS effects on boys versus girls are moderated by numerous factors, not all of which are understood.