Disrupted sensory gating in pathological gambling.
BACKGROUND
Some neurochemical evidence as well as recent studies on molecular genetics suggest that pathologic gambling may be related to dysregulated dopamine neurotransmission.


METHODS
The current study examined sensory (motor) gating in pathologic gamblers as a putative measure of endogenous brain dopamine activity with prepulse inhibition of the acoustic startle eye-blink response and the auditory P300 event-related potential. Seventeen pathologic gamblers and 21 age- and gender-matched healthy control subjects were assessed. Both prepulse inhibition measures were recorded under passive listening and two-tone prepulse discrimination conditions.


RESULTS
Compared to the control group, pathologic gamblers exhibited disrupted sensory (motor) gating on all measures of prepulse inhibition. Sensory motor gating deficits of eye-blink responses were most profound at 120-millisecond prepulse lead intervals in the passive listening task and at 240-millisecond prepulse lead intervals in the two-tone prepulse discrimination task. Sensory gating of P300 was also impaired in pathologic gamblers, particularly at 500-millisecond lead intervals, when performing the discrimination task on the prepulse.


CONCLUSIONS
In the context of preclinical studies on the disruptive effects of dopamine agonists on prepulse inhibition, our findings suggest increased endogenous brain dopamine activity in pathologic gambling in line with previous neurobiological findings.
Stojanov
Wendy
W
Clinical Neuroscience Program, Hunter Medical Research Institute, Callaghan, NSW, Australia.
Karayanidis
Frini
F
Johnston
Patrick
P
Bailey
Andrew
A
Carr
Vaughan
V
Schall
Ulrich
U
D000161:Acoustic Stimulation; D000328:Adult; D001767:Blinking; D016022:Case-Control Studies; D004192:Discrimination, Psychological; D007174:Disruptive, Impulse Control, and Conduct Disorders / Q000378:metabolism / Q000503:physiopathology; D004298:Dopamine / Q000378:metabolism*; D018913:Event-Related Potentials, P300; D005072:Evoked Potentials, Auditory; D005260:Female; D005715:Gambling; D006801:Humans; D008297:Male; D008875:Middle Aged; D009433:Neural Inhibition; D013216:Reflex, Startle
D004298:Dopamine