Measures of response inhibition yield a more inconsistent picture, however. Lawrence and colleagues (2009a) investigated action cancellation function using the Stop-Signal procedure. These authors observed deficits in both the stop-signal reaction time (SSRT) and in basic psychomotor speed (“go” reaction times) in the alcohol-dependent participants, but the problem gamblers and healthy controls did not differ on either measure (SSRT means = 185 ms and 184 ms, respectively). While an earlier study did report a significant SSRT deficit in a (more severe) group of treatment-seeking pathological gamblers (Goudriaan et al., 2006), this was not substantiated in a further study in which only gamblers with co-morbid ADHD were impaired (Rodriguez-Jimenez et al., 2006).
