Table 1. Mean (±SEM) Number of Risky Choices for Each Probability Block Separated by ‘Wins' and ‘Losses'.

	Wins	Stays	Losses	Shifts
SCH 23 390
1 μg
100%	7.9 (0.5)	7.1 (0.7)
50%	2.6 (0.5)	1.8 (0.5)	2.9 (0.5)	0.9 (0.2)
25%	0.9 (0.3)	0.9 (0.3)	3.7 (0.7)	1.2 (0.2)
12.5%	0.4 (0.2)	0.2 (0.1)	2.9 (0.8)	1.2 (0.3)
Saline
100%	8.3 (0.3)	7.5 (0.6)
50%	3.7 (0.6)	3.2 (0.6)	3.3 (0.5)	0.5 (0.3)
25%	1.2 (0.3)	0.8 (0.3)	4.8 (0.6)	1.3 (0.2)
12.5%	0.5 (0.1)	0.2 (0.1)	4.2 (0.7)	1.7 (0.4)
PD 128 907
1.5 μg
100%	6.8 (0.5)	5.9 (0.7)
50%	2.3 (0.4)	1.9 (0.5)	3.3 (0.8)	0.5 (0.3)
25%	1.6 (0.2)	1.2 (0.3)	3.4 (0.4)	1.3 (0.2)
12.5%	0.5 (0.2)	0.2 (0.1)	3.9 (0.7)	1.6 (0.3)
Saline
100%	8.3 (0.3)	7.8 (0.5)
50%	3.9 (0.4)	3.4 (0.5)	3.4 (0.3)	0.8 (0.3)
25%	1.0 (0.2)	0.6 (0.2)	5.1 (0.5)	1.7 (0.3)
12.5%	0.4 (0.2)	0.3 (0.2)	4.7 (0.6)	2.0 (0.4)

‘Stays' are choices on the large/risky option immediately subsequent to a rewarded risky choice; ‘shifts' are those trials for which the small/certain option was selected following an unrewarded risky choice.