Delta and theta oscillations as risk markers in adolescent offspring of alcoholics.
BACKGROUND
Visual P300 is consistently lower in alcohol-dependent individuals, their offspring and subjects at risk. Delta and theta event-related oscillations (ERO) are the major contributors to the P300 signal. The total and evoked power in delta and theta bands in the 300 to 700 ms post-stimulus window (corresponding to the zone of P300 maxima) was compared between adolescent offspring of alcoholics (high-risk) and age-matched normal controls (low-risk), to assess the utility of the risk markers.


METHODS
EEG was recorded during the performance of a visual oddball task. The S-transform algorithm decomposed the EEG signals into different frequency bands and the group differences in total and evoked power in the oscillatory responses during the P300 time window (300 to 700 ms) were analyzed using a multivariate design. Similar analysis was performed on P300 peak amplitude for the target.


RESULTS
The high-risk group showed significantly lower parietal post-stimulus evoked and total power in the delta band for targets. A decrease in total power was seen centrally and parietally in the theta band. The P300 peak amplitude in the parietal electrodes was also significantly lower in the high-risk group.


CONCLUSIONS
The decreased total theta power and total and evoked delta power for visual targets in high risk individuals may serve as an endophenotypic marker in the development of alcoholism and other disinhibitory disorders. The differences seen between the offspring of alcoholics and controls may have a cholinergic basis. The ERO measures appear to be more robust than the P300 amplitude in differentiating the groups.
Rangaswamy
Madhavi
M
Department of Psychiatry, State University of New York, Health Science Center at Brooklyn, NY 11203, USA. mr@cns.hscbklyn.edu
Jones
Kevin A
KA
Porjesz
Bernice
B
Chorlian
David B
DB
Padmanabhapillai
Ajayan
A
Kamarajan
Chella
C
Kuperman
Samuel
S
Rohrbaugh
John
J
O'Connor
Sean J
SJ
Bauer
Lance O
LO
Schuckit
Marc A
MA
Begleiter
Henri
H
D000293:Adolescent; D000437:Alcoholism / Q000453:epidemiology / Q000235:genetics* / Q000503:physiopathology*; D000513:Alpha Rhythm; D015415:Biomarkers; D001931:Brain Mapping; D016241:Child of Impaired Parents / Q000523:psychology*; D003700:Delta Rhythm; D018913:Event-Related Potentials, P300 / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D010775:Photic Stimulation / Q000379:methods; D013057:Spectrum Analysis; D013997:Time Factors
D015415:Biomarkers