primary target of the VTA, serves as a limbic-motor interface that processes reward valence and modulates motivational drives in order to execute both novel and more habitual responding (Kelley, 2004; Koob and Le Moal, 2001; Mogenson et al., 1993; Nestler, 2005; Nicola et al., 2000; Pierce and Kumaresan, 2006; Smith, 2004). The NAcb has two main regions, with the NAcb core important for control of motivated behavior by conditioned cues, and the NAcb shell most often implicated in processing of primary reward and novelty.
