. Author manuscript; available in PMC: 2019 Oct 1.

Published in final edited form as: Psychopharmacology (Berl). 2018 Sep 3;235(10):3005–3015. doi: 10.1007/s00213-018-4990-9

Table 1.

Summary of results.

	Light Access	Dark Access	Low Drug Takers	High Drug Takers
Infusions	+	++	+	++
First Hour Infusions	+	+	+	++
Active Licks	+	++	+	++
Inactive Licks	-	-	-	-
Goal-Directed Behavior	+	++	+	+
Progressive Ratio	+	+	+	++
Extinction 1 and 2	+	++	+	+
Incubation	+	++	+	+
Reinstatement	+	+	+	++
Extinction Switch	+	-	NA	NA

+ reflects responding for drug.

++ reflects increased responding for drug significant at p<0.05 vs. +.

− reflects reduced responding for drug.