BEHAVIOURAL CHOICE THEORIES OF ADDICTION. Nick Heather PhD, Centre for Alcohol & Drug Studies, Newcastle, North Tyneside & Northumberland Mental Health NHS Trust, & University of Northumbria. THE LANGUAGE OF CHOICE.
Nick Heather PhD,
Centre for Alcohol & Drug Studies,
Newcastle, North Tyneside & Northumberland Mental Health NHS Trust,
& University of Northumbria
ABNORMAL DESIRE FOR DRUG OR ACTIVITY (“CRAVING”)
AKRASIA OR “WEAKNESS OF WILL”CONCEPTUAL FRAMEWORK FOR EXPLAINING ADDICTION
NEUROADAPTION OR PRE-EXISTING DIFFERENCES IN NEURAL RESPONSE
From: Heather, N. (1998) A conceptual framework for explaining drug addiction, Journal of Psychopharmacology, 12, 3 - 7
TimeHYPERBOLIC DISCOUNT CURVES BEHAVIOURAL CHOICE THEORIES
Hyperbolic discount curves from two rewards of different sizes available at different times (vertical dashed lines). The smaller-sooner reward is temporarily valued higher (preferred) for a period just before it’s available, as shown by the portion of its curve that projects above that of the later-larger reward.
Where V is value, A is the undiscounted reward value, D is delay and k is a constant describing the individual subjects degree of impatience. Functions in this class are referred to as hyperbolic as contrasted with exponential functions which model temporal discounting as occurring at a fixed rate over time.
1 + kD
Local Utility of Drug Consumption
Local Utility of Other Activities
Heavy drug use
Relative Behavioural Allocation to Drug Consumption
[Drug Consumption/ (Drug Consumption + Other Activities)]
Utility of Drug Consumption
Utility of Other Activities
Marginal Utility of Drug Consumption
Heavy Drug Use
Stock of Addictive Capital