, 2010). However, CN fibers do not terminate in the NAc shell; instead they presumably influence NAc activity via an indirect pathway through midbrain DA-expressing neurons. Consistent

with this, inactivation of the ventral tegmental area abolished PIT (Corbit et al., 2007), whereas dopaminergic receptor blockade in the NAc attenuated transfer (Lex & Hauber, 2008). Conversely, amphetamine, which increases DA vesicular release, potentiates PIT after being selectively Tofacitinib concentration infused into the shell (Parkinson et al., 1999; Wyvell & Berridge, 2000). Thus, as the anatomical projections from the amygdala complex at the level of the ventral striatum (whether direct or indirect) are heavily intermixed, these functional MG-132 chemical structure parallels suggest that there is probably a necessary interplay between glutamatergic and dopaminergic processes that may differentially impact the ways in which motivational and detailed sensory information is coded within the NAc. In conclusion, these results present an important basis for understanding the neural underpinnings of PIT in the NAc, and how this neural circuit is fundamentally altered following repeated exposure to cocaine and its resultant modulation of DA action in the NAc. Future work will need to investigate how this neural encoding acts within larger circuits of the limbic system such as the amygdala and dorsal striatum, and how such circuits

are modulated by DA inputs. The authors thank Dr Peter Holland for early discussions of experimental design, and Jon Sugam and Dr Erin Kerfoot for helpful discussions of earlier drafts of this work. This research was supported by DA028156 to M.P.S. and DA014339 to R.M.C.

Abbreviations BLA basolateral amygdala CN central nucleus of the amygdala CS+ conditioned stimulus Histone demethylase CS- non-reinforced conditioned stimulus DA dopamine PIT Pavlovian-to-instrumental transfer VI variable interval Fig. S1. Histological locations of all valid array wires. Valid wires were those that were located within either the core or shell of the NAc, and did not extend caudally beyond AP. level +0.7. (A) Wires for all naive subjects. Ten animals were used in this study; however, in two animals, one of the arrays failed to have any wires in either the core (n = 1) or shell (n = 1). Thus, neural firing was recorded from nine shell and nine core arrays. Note that virtually all shell recordings were located on the medial aspect of the shell. (B) Wires for all valid saline-treated controls. (C) Wires for all valid cocaine-treated animals. As a service to our authors and readers, this journal provides supporting information supplied by the authors. Such materials are peer-reviewed and may be re-organized for online delivery, but are not copy-edited or typeset by Wiley-Blackwell. Technical support issues arising from supporting information (other than missing files) should be addressed to the authors.