Transcript Models of addiction

Have we got the balance right?
Return on investment from brain,
behavioural and social sciences in
the field of addiction
Robert West
University College London
@robertjwest
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Declaration of interests
• I undertake research and consultancy for companies that
develop and manufacture smoking cessation medications
• I am a trustee of QUIT
• I am co-director of the NHS Centre for Smoking Cessation and
Training
• My salary is funded by Cancer Research UK
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Outline
1. Definitions
2. Models of addiction
3. A strategy for developing and evaluating behaviour change
interventions
4. Where can we best deploy future resources?
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Defining addiction
An individual is addicted to an activity (characteristically
ingestion of a drug) to the extent that he or she experiences
repeated strong motivation to engage in it as a result of
learning, with potentially harmful consequences1
Strength
The relative strength of motivation to engage in the
addictive behaviour relative to other activities
Severity
The degree of current or expected harm arising from
the addictive behaviour
1Developed from West and Brown 2013 Theory of Addiction. Oxford: WileyBlackwell
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Neuroscience and behavioural science
Neuroscience
• a branch of the life sciences that deals with the anatomy,
physiology, biochemistry, or molecular biology of nerves
and nervous tissue and especially with their relation to
behaviour and learning
Behavioural science
• a branch of science (drawing on psychology,
neuroscience, economics, sociology, or anthropology) that
deals primarily with human action and often seeks to
generalize about human behaviour in society
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Neuroscience and behavioural science
Neuroscience
Behavioural
science
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Defining return on investment
• Return on investment from scientific study of a problem is
the benefit to society arising from that study
• This may involve
• Creating a societal and/or professional level of
understanding that generates more adaptive ways of
thinking about that problem
• Developing better specific interventions for addressing
the problem
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Models of addiction
What is causing the high relative strength of motivation?1
Model
Cause of addiction
Powerful reward
Enjoyment or satisfaction
Self-medication
Attempted alleviation of distress or dysfunction
Withdrawal relief
Relief from adverse effects of abstinence
Acquired drive
Strong learned biologically generated wants and
needs
Impaired executive
function
Low self-control in the face of internally and
externally generated motivational pressures
Habit
Strong learned stimulus impulse associations
Social construct
Label used by individuals and social groups to
serve particular functions
1West
(2014) Models of Addiction. Lisbon: EMCDDA
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Focusing on specific interventions to combat
addiction: ‘Intervention functions’
• Education (inform)
• Persuasion (promote)
• Incentivisation (provide material rewards)
• Coercion (imprison, tax, fine, disapprove)
• Training (develop life skills)
• Restriction (set rules)
• Environmental restructuring(reduce access, restrict marketing)
• Modelling (set an example)
• Enablement (medicate, counsel, support)
Michie et al 2013 The Behaviour Change Wheel Guide to Intervention
Development. London: Silverback
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Strategy for developing behaviour change
interventions
1.
2.
3.
4.
Define behavioural target
Behavioural diagnosis
Identify potentially useful broad intervention functions
Develop and implement more specific behaviour change
techniques (BCTs)
5. Cycle through development, implementation and testing
as required
www.behaviourchangewheel.com
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The COM-B Model of behaviour (Rev 1)
Influences
Moderate influence
Psychological
Physical
Capability
Reflective
Automatic
Motivation
Physical
Social
Opportunity
Behaviour
1Michie
et al 2013 The Behaviour Change Wheel Guide to Intervention
Development. London: Silverback
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Behavioural diagnosis in addiction
What needs to change in order to combat addiction in a given
context for a given population?
Psychological
capability
Improve effectiveness of self-regulatory processes
and activities
Reflective
motivation
Induce greater perceived cost and lower
perceived benefit, or more effective plans
Automatic
motivation
Reduce the addictive want, need, or habit, and/or
strengthen competing wants, needs or habits
Physical
opportunity
Restrict access and physical cues
Social opportunity
Reduce supporting norms and social cues and/or
increase conflicting norms
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Ontology of behaviour change interventions
Mechanisms of action cannot be seen in isolation
Content
Delivery
Intervention
Mechanism of
action
Outcome
Effect size
Confidence
Usage
Context
Reach
Engagement
Population
Setting
Other
behaviours
Michie and West 2015
Manuscript under review
Neuroscience and mechanisms of action
• Identify relevant
• Neuro-anatomical structures
• Neurochemical activity
• Goal is to
• Find better drug targets
• Inform psychological and social interventions
• Improve understanding of the brain
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Contribution of neuroscience to specific
interventions
Contribution
An intervention or intervention strategy that has been
developed from, or informed by, theories and models in
neuroscience
Addictive behaviour
Contribution1
Tobacco
Varenicline, nicotine replacement therapy,
bupropion, cytisine
Stimulants
?
Alcohol
Acamprosate, Naltrexone
Opiates
Methadone, Buprenorphine
Cannabis
?
Gambling
?
1Based
on Cochrane reviews
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Contribution of psychological and social
sciences
Addictive behaviour
Contribution1
Tobacco
Price increases, social marketing, brief advice,
financial incentives, behavioural support for
cessation, refusal skills training
Stimulants
Contingency management
Alcohol
Price increases, access restriction, brief
advice, online support
Opiates
?
Cannabis
?
Gambling
?
1Based
on Cochrane reviews
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The future
• Need a major review of research strategy underpinning
approaches to combating addiction
• It needs to
• Set clear criteria against which to assess potential
contribution
• Use a comprehensive, coherent framework for
understanding behaviour change
• Involve a reflective approach in which all options are
considered against the relevant criteria
• Make recommendations to funders for research priorities
in terms of amounts and topics
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