Table 1.

Statistical output from Experiment 1.

	Model	df	AIC	BIC	logLik	Test	L.Ratio	p-value
Acquisition of methamphetamine self-administration
Baseline Model	1	6	821.06	835.36	−404.53
Adding Session Factor	2	7	822.63	839.31	−404.32	1 vs 2	0.43	0.51
Adding Lever Factor	3	8	699.43	718.48	−341.71	2 vs 3	125.21	0.00
Adding Session × Lever	4	9	699.51	720.95	−340.76	3 vs 4	1.92	0.17
The effect of NAC on responding for methamphetamine
Baseline Model	1	5	321.66	328.99	−155.83
Adding Dose Factor	2	8	327.03	338.76	−155.52	1 vs 2	0.63	0.89
Adding Activity Factor	3	9	328.54	341.73	−155.27	2 vs 3	0.49	0.48
Adding Dose × Activity	4	12	321.23	338.82	−148.62	3 vs 4	13.30	0.00
The effect of NAC on methamphetamine-triggered reinstatement
Baseline Model	1	5.00	259.53	265.42	−124.76
Adding Dose Factor	2	8.00	262.67	272.09	−123.33	1 vs 2	2.86	0.41
Adding Activity Factor	3	9.00	261.42	272.02	−121.71	2 vs 3	3.25	0.07
Adding Dose × Activity	4	12.00	264.08	278.22	−120.04	3 vs 4	3.34	0.34