Understanding the nature of addictive behaviour can help in
raising self awareness and so enable informed self-reflection of all stages of
the stimulus response cycle addiction. Many techniques including hypnosis and CBT
imagine and practice changes that lead to changes in both behaviour and cognition.
The pleasure versus wanting bind
Experimental
animals like people will often continue or increase consumption of freely
available foods and drugs. This pertains to other pleasurable behaviours like
chocolate and sex. The mesolimbic dopamine system is active when addictive
drugs are consumed or when they are introduced directly into the brain.
Excluding instinctual behaviours conditioning theory posits contingency to set
up learning/reinforcing behavioural sequences. This stimulus-response(S-R) once
learned and practiced can often becomes automatic, e.g. driving, smoking or
alcohol consumption.
In
animal studies behaviour is contingent with ‘reward’,
the animal is rewarded for its operant behaviour. Addictive substances hijack
the mesolimbic system, exciting the same dopaminergic neurons involved in
rewarding/learning. The question arises as to where pleasure belongs in S-R, is
wanting different from liking?
The
dissociation between wanting and liking is addressed by Berridge, (1999) in the incentive-sensitisation theory. Wanting
at preconscious levels involve conditioned homeostatic neural responses to
salient drug related cues, acting on a dopamine system already sensitised to
drug use. Heightened wanting in this sensitised sense is craving, dopaminergic
circuits initiate craving and prime learned drug seeking behaviours below the
level of conscious awareness. Typically addicts subjectively rate very low
doses of cocaine as worthless but will continue to work to obtain them, Fischman and Foltin,(1992).
According
to Berridge animal studies have tended to
confound wanting and liking and Berridge
concludes that dopamine levels affect wanting but not liking, evidenced by rat
facial expressions. Additionally the discovery of naturally occurring
endogenous opioids Carlson pp 128,9
supports the separation of wanting from liking.
In summary the separation of pleasure from wanting, with
their corresponding substrates in the brain, seems to reflect how these are
experienced differently and explain the aetiology of addiction: its changing
profile from pleasure to craving.
John Jeffrey, Sept 2010 Return to welcome page
References:
Berridge, K. C., (1999), ‘Pleasure,
pain, desire, and dread: Hidden core processes of emotion’. In D. Kahneman, E. Diener, & N.
Schwarz (Eds.), Well-being: The
foundations of hedonic psychology pp.525–557. New York, NY:
Russell Sage Foundation
Carlson, N. R., (2007), ‘Physiology of Behaviour’, 9th
Edition’, Pearson International, USA
Fischman,(1992), cited by Berridge pp.531.