Table 1.

Asterisks indicate a significant difference (p < 0.05) from vehicle condition on omissions, locomotor activity, or shock reactivity (as indicated at the top of each column). Data are represented as mean (± SEM). Veh refers to vehicle administration, B/M refers to baclofen/muscimol administration, and amph refers to amphetamine administration. There were insufficient data in Experiment 3.2 to calculate the means for shock reactivity for all conditions in which amphetamine was administered (most rats never chose the large, risky reward).

Experiment	% Omitted Trials		Locomotion (locomotor units/ITI)	Shock reactivity (locomotor units/shock)
	Free	Forced
Intra-mPFC inactivation
Experiment 1.1
Vehicle	0.92 (0.62)	12.50 (4.05)	17.16 (2.63)	2.76 (0.30)
B/M	6.0 (1.94)*	8.84 (2.56)	18.30 (2.21)	2.77 (0.25)
Experiment 1.2
Vehicle	0.83 (0.52)	4.79 (2.49)	18.78 (1.86)	3.30 (0.30)
B/M	1.67 (0.64)	1.88 (1.07)	20.32 (2.41)	2.85 (0.40)
Intra-mPFC amphetamine
Experiment 2.1
0 μg	5.40 (1.61)	6.75 (2.50)	23.02 (2.49)	3.14 (0.29)
2.0 μg	8.40 (4.48)	10.50 (3.14)	12.68 (2.04)	3.20 (0.19)
10.0 μg	7.00 (2.67)	6.00 (2.26)	23.98 (2.04)	2.93 (0.15)
20.0 μg	10.80 (4.70)	15.15 (4.65)	24.61 (1.65)	3.03 (0.28)
Experiment 2.2
0 μg	4.67 (2.47)	8.86 (4.16)	17.76 (1.54)	3.24 (0.32)
2.0 μg	3.17 (0.87)	7.05 (1.01)	17.12 (1.46)	3.19 (0.45)
10.0 μg	12.67 (8.22)	12.64 (4.63)	17.82 (1.34)	3.06 (0.13)
20.0 μg	2.17 (0.67)	6.27 (3.03)	20.71 (1.50)	3.50 (0.62)
Intra-mPFC inactivation plus systemic amphetamine (1.5 mg/kg)
Experiment 3.1
Veh, veh	0.0 (0.0)	5.71 (4.90)	16.89 (1.93)	2.68 (0.65)
B/M, veh	4.29 (4.29)	2.50 (2.50)	16.21 (2.48)	2.51 (0.55)
Veh, amph	27.43 (6.64)*	41.43 (4.94)*	26.46 (3.14)*	2.35 (1.05)
B/M, amph	16.86 (4.97)*	30.36 (6.65)*	24.83 (3.18)	3.04 (0.60)
Experiment 3.2
Veh, veh	0.29 (0.29)	2.86 (2.07)	22.97 (2.33)	4.02 (0.28)
B/M, veh	2.86 (2.86)	5.07 (2.16)	20.94 (2.88)	3.67 (0.25)
Veh, amph	22.29 (9.91)	53.93 (3.89)*	33.84 (2.22)*
B/M, amph	18.57 (6.32)	53.21 (3.36)*	28.67 (2.75)