Figure 4.

Restlessness: number of inadequate pokes per trial towards SS hole. Mean (±SEM) number per trial of SS-inadequate pokes (i.e., performed during the postchoice TO interval, when they were without any consequence). Subjects are the same as in Figure 2. While “non-gambler” marmosets showed a progressive increase of inadequate nose-pokes with decreasing levels of probability, “gambler” marmosets did not. Rats exhibited an intermediate profile. **P < 0.01 gambler marmosets significantly different from non-gambler marmosets in post hoc test; ^($)0.05 < P < 0.1 non-gambler marmosets significantly different from non-gambler rats in post hoc test.