Figure 2.

Experimental tests of goal-directed dysfunction in OCD. Reproduced with permission from [48–50]. (a) OCD patients show a tendency towards habit formation following appetitive instrumental training. Habits are assessed using an outcome-devaluation test wherein one outcome is ‘devalued’ and another remains valuable. Responding to stimuli that predict devalued outcomes is evidence for dominant stimulus–response habit associations [62]. (b) In an economic choice task, OCD patients exhibit impaired use of prospective action–outcome comparisons relative to controls [63]. (c) OCD patients exhibit dominant stimulus–response habit associations in a devaluation test following instrumental shock avoidance training [64]. Error bars denote standard error of the mean.