A. The effect of baseline performance in the sustained attention task on set shifting performance. The high performance group required significantly fewer trials to criteria in the extra-dimensional shift compared to the low performance group [F(1,21)=13.758, p<0.001]. These data suggest that animals with better sustained attention may have better behavioral flexibility. B. The effect of MPH on low performance sustained attention animals in the set shifting task. MPH significantly decreased the number of trials to criteria in the extra-dimensional shift in animals with a low baseline level of performance in the sustained attention task [F(1,21)=30.556, p<0.001]. C. The effect of MPH on high baseline sustained attention animals in the set shifting task. MPH significantly impaired performance in the set shifting task by increasing the number of trials to criteria in both the intra-dimensional [F(1,20)=19.563, p<0.001] and extra-dimensional stages [F(1,20)=17.401, p<0.001] in animals with a high baseline level of performance in the sustained attention task