Acting with the future in mind is impaired in long-term opiate users

Gill Terrett, Amanda Lyons, Julie D. Henry, Clare Ryrie, Thomas Suddendorf, Peter G. Rendell

Episodic foresight is a fundamental human capacity. It refers to the ability to simulate future situations and organise current actions accordingly. While there is some evidence that opiate users have a reduced capacity to imagine themselves in future situations, no study to date has assessed whether opiate users show deficits in the ability to take steps in the present in anticipation of future needs. In this study, we assessed whether this functional aspect of episodic foresight is impaired in chronic opiate users and the extent to which any deficits are associated with executive dysfunction. Participants were 33 long-term opiate users enrolled in an opiate substitution program and 34 controls. Relative to controls, the opiate users displayed significant impairment (medium effect size η (2)p = 0.08) in the two behavioural measures of episodic foresight used (items acquired and items used in the VW Foresight task). Furthermore, executive functioning was associated with foresight ability, although this was restricted to items acquired, and the associations were generally stronger for the control group. These data provide important evidence suggesting that the functional aspect of episodic foresight is disrupted in long-term opiate users. While these deficits appear to have some links to impaired executive control, additional work is needed to gain a more complete understanding of the underlying cognitive and neural mechanisms involved. This, in turn, will have important implications for tailoring interventions with opiate users to maximise the likelihood of successful independent functioning.