Table 2.

Mean (± SEM) intoxication ratings for all groups in Experiments 1–3.

	Experiment 1		Experiment 2		Experiment 3
Day	Massed	Spaced	Immediate	Delay	Master	Yoked
P1	0.73±0.21	0.60±0.19	0.73±0.38	0.36±0.20	0.00±0.00	0.17±0.17
P2	2.67±0.30	1.53±0.41	2.00±0.43	0.82±0.23	1.57±0.57	1.50±0.67
P3	3.87±0.41	3.60±0.38	3.73±0.54	1.73±0.33	1.57±0.75	0.33±0.33
NCC1					0.00±0.00	0.00±0.00
P4	3.40±0.46	2.87±0.36	3.09±0.41	3.18±0.52	2.71±0.97	3.50±0.92
NCC2					0.57±0.57	0.33±0.33
P5	1.80±0.44	2.53±0.34	1.18±0.66	3.55±0.51	1.43±0.84	1.83±0.65
NCC3					0.00±0.00	0.33±0.33
P6					0.29±0.29	0.67±0.42
NC1	0.93±0.33	0.20±0.20	0.00±0.00	0.09±0.09	0.14±0.14	0.67±0.42
NC2	0.47±0.27	0.20±0.20	0.00±0.00	0.00±0.00	0.29±0.29	0.33±0.33
CH1	0.47±0.27	0.27±0.27	0.00±0.00	0.00±0.00	0.00±0.00	0.00±0.00
CH2	0.13±0.09	0.00±0.00	0.00±0.00	0.00±0.00	0.00±0.00	0.17±0.17

Note: On days in which passive infusions were delivered (P1-6) intoxication ratings were made 6 h after the start of the last infusion. On self-infusion days, No-Choice Control (NCC1-3), No-Choice (NC1-2) and Choice (CH1-2), intoxication ratings were made at the end of the 23-h session (in the mid-afternoon). No signs of intoxication were observed after CH2. Days NCC1-3 and P6 were only included in Experiment 3.