should be particularly sensitive to general transfer effects as they are not associated with detailed sensory representations of the outcome [23]. Anatomically, the basolateral nucleus of the amygdala (BLA) is thought to encode emotional events with reference to their sensory-specific features while the central nucleus (CeA) encodes general motivational or affective signifi- cance [24]. Consistent with this framework, the BLA is required for specific transfer while general transfer involves the CeA [25,26]. These data imply that during general transfer, activation of the CeA preferentially engages brain structures that encode habits. A recent study suggests that this may be the case. Lingawi & Balleine (2012) examined interactions between the CeA and the dorsolat- eral striatum (DLS), a structure that is essential for habit learning in humans and animals [3,27,28]. They found that disconnecting the anterior CeA and DLS prevented the acquisition of habitual responding when rats were over-trained [29]. This suggests that the CeA provides an important reinforcement signal to the DLS as habits are being acquired. In the same study, lesions of the CeA also prevented Pavlovian cues from motivating instrumental responding during a transfer test. However, the effects of References 1. Dickinson A (1994) Instrumental conditioning. In: Mackintosh NJ, editor. Animal Learning and Cognition. Orlando, FL: Academic Press. 2. Mackintosh N (1983) Conditioning and associative learning. Oxford: Clarendon. 3. Yin HH, Knowlton BJ (2006) The role of the basal ganglia in habit formation. Nat Rev Neurosci 7: 464–476. 4. Dickinson A (1985) Actions and habits: the development of behavioural autonomy. Philos Trans R Soc Lond B: 67–78. 5. Poldrack RA, Sabb FW, Foerde K, Tom SM, Asarnow RF, et al. (2005) The neural correlates of motor skill automaticity. 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Ratio and Interval Training disconnecting the CeA and DLS on transfer were not examined. Additional studies are therefore needed to determine if signaling between the CeA and DLS is required for reward cues to motivate habitual responding. The current results may also be relevant to addiction, which is mediated by drug seeking responses that are automatic and insensitive to consequences [8,10,30]. A major source of relapse in addicted individuals, results from exposure to environments and stimuli that are associated with drugs [6,10]. Our data suggest that the emotional impact of reward cues may be particularly strong motivators of drug seeking behavior precisely because these responses are habitual. If this is the case, then interventions that alter affective responses elicited by drug-associated stimuli should serve as particularly effective treatments. Author Contributions Conceived and designed the experiments: BJW. Performed the experi- ments: BJW CS CL FB MM CCH. 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