Table 3.

Baseline Responding: Experiment 1 (Mean ± SEM per 10 min interval)^*

	Experimental Condition
	Nal-Naive	Unpaired	Paired-No CS	Paired-CS
Pre-CS Interval:	902 ± 83.5	932 ± 54.4	899 ± 46.1	881 ± 48.7
CS Interval:
CS 1–10	860 ± 74.7	944 ± 56.5	803 ± 38.8	872 ± 39.6
CS 11–20	647 ± 36.3	628 ± 37.0	556 ± 38.2	620 ± 52.4

^*Baseline responding reflected an average of the last 3 days prior to the first Conditioning Session