Age and gender effects in EEG coherence: I. Developmental trends in normal children.
OBJECTIVE
This study investigated intra-hemispheric and inter-hemispheric EEG coherences as a function of age and gender in normal children.


METHODS
Two groups of 40 boys and 40 girls, each containing 8 normal children in each 1-year band from 8 to 12 years, participated. EEG was recorded from 21 sites during an eyes-closed resting condition. Wave-shape coherence was calculated for 8 intra-hemispheric electrode pairs (4 in each hemisphere), and 8 inter-hemispheric electrode pairs, within each of the delta, theta, alpha and beta bands.


RESULTS
There was consistent evidence of coherences developing across this age range, particularly in long-range intra- and inter-hemispheric electrode pairs. Coherences were larger in the left hemisphere than the right. Coherences also appeared to develop further in males than females, across several regions and frequency bands, suggesting that females lag males in this aspect of brain development.


CONCLUSIONS
EEG coherences in normal children of this age range develop systematically with age. These developmental effects vary substantially with gender, brain region and frequency bands.


CONCLUSIONS
The data reported here provide basic norms for coherence development in different brain regions in normal children.
Barry
Robert J
RJ
Brain & Behaviour Research Institute and Department of Psychology, University of Wollongong, Northfields Avenue, Wollongong, NSW 2522, Australia. robert_barry@uow.edu.au
Clarke
Adam R
AR
McCarthy
Rory
R
Selikowitz
Mark
M
Johnstone
Stuart J
SJ
Rushby
Jacqueline A
JA
D000375:Aging / Q000502:physiology*; D002648:Child; D002657:Child Development / Q000502:physiology*; D004569:Electroencephalography; D005260:Female; D007839:Functional Laterality; D006801:Humans; D008297:Male; D012016:Reference Values; D012727:Sex Characteristics