It is worth noting that as applied to

It is worth noting that, as applied to individuals from harsh and chaotic early life circumstances, potentiated activity in neural systems supporting reward anticipation can be viewed as a kind of central l-ascorbic acid pathology—a wound (cf., McEwen and Gianaros, 2011). Indeed, heightened reward anticipation is implicated in several behavioral disorders (e.g., Beck et al., 2009; Plichta and Scheres, 2014; Sweitzer et al., 2016). In our view, however, one advantage of the LHT perspective is its characterization of increased reward anticipation under harsh and unpredictable life circumstances not as a wound so much as an adaptive trade-off, which implies that more frequent and intense reward anticipation is an advantage under harsh and unpredictable circumstances—indeed, that those circumstances might result in additional adaptive advantages. Very recent work supports this view. For example, higher striatal reward anticipation may protect against depression following childhood neglect (Hanson et al., 2015), and children from low-resourced backgrounds who behave impulsively seem to have more robust cardiac vagal tone, a putative marker of resilience (Sturge-Apple et al., 2016). With these and related observations in mind, Replication-defective virus may be useful in future work for researchers to elucidate the functional role of potentiated reward anticipation across a variety behaviors both adaptive and maladaptive.
Conflict of interest
Acknowledgements This work was supported by a grant from the National Institute of Mental Health (R01MH080725) awarded to James A. Coan and grants from the National Institute of Child Health and Human Development and the National Institute of Mental Health (9R01 HD058305-11A1 & R01-MH58066) awarded to Joseph P. Allen.