86 Reported lifetime gambling increased for both males and females from 1975 to 1998; however, the increase was much larger for women, from 61 % to 83%, than for men, from 75% to 88%, resulting in a decrease in the sex

MLN2238 concentration difference in gambling.84 Yet, past-year gambling remains unchanged for men, 68% versus 67%, while it increased slightly for women from 55% to 60%, resulting in only a slight decrease in the sex difference.84 Legalized gambling has led to more gambling opportunities and new forms87; the explosion seems likely to account for the decrease in the sex difference in social gambling, yet the sex difference in PG has remained. This sex difference in PG, with males predominating Inhibitors,research,lifescience,medical in both clinical and population samples, is in contrast to the sex parity often found in OCD and BDD. Gender differences have also been reported in the onset and course of PG. In males, PG usually begins in adolescence88-90 or young adulthood,90 and may remain undiagnosed Inhibitors,research,lifescience,medical for years. When male PG patients are first diagnosed, they often present with a 20- to 30-year gambling history, with gradual development of PG. In some cases, PG suddenly

occurs in male social Inhibitors,research,lifescience,medical gamblers following a significant loss, stressor, or increased exposure.91 In contrast, PG in females is more likely to occur later in life and delay in seeking treatment is approximately Inhibitors,research,lifescience,medical 3 years. Thus, as a result of the differences in onset and duration, female PG patients generally have a better prognosis than male PG patients.91 Male and female gamblers

differ in the types of gambling they prefer, with men more likely to bet on sporting events, cards, and at the track, while women prefer slot machines and bingo.90 It is unknown whether males and females with PG represent truly different sub-groups with differences in Inhibitors,research,lifescience,medical pathophysiology and treatment response. We recently completed an FDG (fluorodeoxyglucose) positron emission tomography (PET) study in PG. The scans were acquired while the patients were engaged in a computerized gambling task either for a monetary reward GBA3 or for computer points only. Gambling for monetary reward blackjack was associated with significantly higher relative metabolic rate in the primary visual cortex, the cingulate gyrus, the putamen, and prefrontal areas. We would expect normal subjects to show activation in both monetary and pure gambling conditions, but a study including both PG and social gamblers has not yet been done. In addition to demonstrating that the unique aspects of monetary reward compared with pure gambling are reflected in the activation patterns similarly to past imaging studies of reward strategy planning,92 the results arc generally consistent with symptom-provocation studies in OCD. A possible selective efficacy of SRIs has been demonstrated in PG.