One implication of this assumption is that the externalizing and internalizing pathways are not necessarily orthogonal; rather they define different risk processes leading to SUDs that may at times be overlapping. In other words, emerging risk for SUDs is governed for some children by processes underlying both the internalizing and externalizing pathway and these may indeed be processes that put youth at risk for SUDs more generally rather than Negative Affect SUDs in particular. One example of this overlap comes from research on anger management and aggression in which cognitive-behavioral interventions to manage anger (and increase social problem solving skills) in aggressive boys reduced risk for substance use at one year follow-up (Lochman & Wells, 2003). These risk processes for SUDs are consistent with those acknowledged in the externalizing pathway. Likewise, to the extent that children who have problems with anger management also show problems regulating other forms of emotion (e.g., fear and sadness), the processes relating anger management to subsequent SUDs may also be implicated in the internalizing pathway. Thus, some of the risk processes defining the internalizing and externalizing pathways may at times overlap in the lifecourse of an individual child.
