Temporal discounting as a measure of executive function: insights from the competing neuro-behavioral decision system hypothesis of addiction.
CONCEPTUAL PAPER PURPOSE: The purpose of this chapter is to examine a new conceptual model of addiction and interpret the results from delay discounting studies in light of this new perspective.


METHODS
To accomplish this we (1) introduce this new conceptual model, (2) briefly review executive function, including evidence for executive dysfunction among the addicted, (3) describe the unique relationship of temporal discounting to the new model and executive dysfunction, and (4) reinterpret the discounting literature in light of this new conceptual model.


RESULTS
Addicted individuals discount the future more than controls. This is consistent with greater relative activation of the impulsive system and decreased relative activation of the executive system. It also supports the new conceptual model of addiction.


CONCLUSIONS
The new model provides a model for understanding the observations from the broader area of research in temporal discounting.


CONCLUSIONS
Given the view of executive function as important for the cross-temporal organization of behavior, we think that temporal discounting, the valuing of future commodities, qualifies this process to be included as an executive function.
Bickel
Warren K
WK
Center for Addiction Research, Fred & Louis Dierks Research Laboratories Psychiatric Research Institute, University of Arkansas for Medical Sciences, Little Rock, AR, USA.
Yi
Richard
R
D016739:Behavior, Addictive; D001921:Brain / Q000502:physiology; D016022:Case-Control Studies; D002755:Choice Behavior; D005717:Games, Experimental; D006801:Humans; D008959:Models, Neurological; D013995:Time