GGZ3025 Verslaving
TASK 4 – VERSLAVING IS EEN KEUZE
ADDICTION AND CHOICE THEORY: THEORY AND NEW DATA
Bron: Heyman (2013)
Research shows that addiction has the highest remission rate of any psychiatric disorder, that
most addicts quit drugs without professional help, and that the correlates of quitting are those
that attend most decisions, such as financial and familial concerns. However, addiction is
‘disease-like’ in the sense that it persists even though on balance its costs outweigh the
benefits (e.g. most addicts eventually quit). In order to explain addiction, we need an account
of voluntary behavior that predicts the persistence of activities that from a global bookkeeping
perspective are irrational.
Likelihood of remission and time course of addiction
The figure shows the cumulative frequency of remission as a function of the onset of
dependence in a nation-wide representative sample of addicts. On the x-axis is the amount of
time since the onset of dependence. On the y-axis is the cumulative frequency of remission,
which is the proportion of individuals who met criteria for lifetime dependence but for the
past year or more had been in remission.
The cumulative frequency of remission
increased each year for each drug. By year 4
since the onset of dependence, half of those who
were ever addicted to cocaine had stopped using
cocaine. For marijuana, the half-life dependence
was 6 years, and for alcohol, the half-life
dependence was 16 years.
The graph also shows that there is much individual variation; among cocaine users, about 5%
continued to meet the criteria for addiction well into their 40s, among marijuana users, about
8% remained heavy users well into their 50s, and for alcoholics, more than 15% remained
heavy drinkers well into their 60s.
Correlates of quitting and the role of treatment
The correlates of quitting include the absence of additional psychiatric and medical
problems, marital status (singles stay addicted longer), economic pressures, fear of judicial
sanctions, concern about respect from children and other family members, worries about the
many problems that attend regular involvement in illegal activities, more years spent in
school, and higher income. Addicts often say that they quit drugs because they wanted to be a
better parent, make their own parents proud, and not further embarrass their families.
1
, GGZ3025 Verslaving
Disease etiology for persistent self-destructive drug use
The authors state that it ‘seems fair to say that who cites selfishness and myopic choices as
evidence of pathology (e.g. she has to be sick because she bought drugs rather than groceries)
naively misread human nature’. Behavioral psychologists and economists have discovered
principles that predict self-defeating, selfish patterns of behavior, including hyperbolic
discounting, melioration and the matching law. These are laws of choice that predict how
someone choices between different commodities and activities. Under some condition, they
predict relatively stable suboptimal patterns of behavior. General principles that apply to
everyday choices also predict compulsive-like consumption patterns in addictions.
These choice laws reflect a basic property of most choices; there is more than one ‘optimal’
strategy. One is optimal from the perspective of the most immediate circumstances, such as
the current values of the options. The others are optimal in terms of wider time horizons and
the perspectives of others. For example, in settings in which current choices affect the values
of future options, it is possible for the current choice to be the worst long-term choice. Thus, it
is possible that the drug is the best choice when the frame of reference is restricted to the
current values of the immediately available options but the worst choice when the frame of
reference expands to include future costs and other people’s needs.
According to this account, persistent drug use reflects the workings of a local optimum,
whereas controlled drug use or abstinence reflects the workings of a global optimum. Put
somewhat differently, whether or not drug use persists depends on the factors that influence
decision making, particularly values that emphasize global as opposed to a local frame of
reference.
But drugs change the brain
As self-administered drug doses greatly exceed the circulating levels of their natural
analogues, persistent heavy drug use leads to structural and functional changes in the nervous
system. It is widely assumed that these neural adaptations play a causal role in addiction. In
support of this interpretation brain imaging studies often reveal differences between the brains
of addicts and comparison groups. however, these studies are cross-sectional and the results
are correlations. There are no published studies that establish a causal link. In principle then
it is possible to hypothesize that drug-induced neural changes play little or no role in the
persistence of drug use.
First, most addicts quit, thus drug-induced neural plasticity does not prevent quitting. Second,
in follow-up studies, there were no increases in preference for cocaine. Third, the figure
(graph) shows that the likelihood of remission was constant over time since the onset of
dependence. Although this is a surprising result, it is not without precedent. A longitudinal
study of heroin addicts reports that the likelihood of going off drugs neither increased nor
decreased over time, and a study in rats reports that the probability of switching from cocaine
to saccharin was independent of past cocaine consumption. Since drugs change the brain,
these results suggest that the changes do not prevent quitting, and the slope of the figure
implies that drug-induced neural changes do not even decrease the likelihood of quitting
drugs once dependence is in place.
2
, GGZ3025 Verslaving
But there is a genetic predisposition for addiction
Studies have repeatedly demonstrated a genetic predisposition for alcoholism, and other
studies on heroin, cocaine and marijuana suggest the same. However, all behavior has a
genetic basis, including voluntary acts. Thus, there is no necessary connection between
heritability and compulsion. The relevance to addiction is that a genetic predisposition is not a
recipe for compulsion, just as brain adaptations are not a recipe for compulsion.
Summary
Most addicts quit using drugs at clinically significant levels, they typically quit without
professional help, and in the case of illicit drugs, they typically quit before the age of 30. The
correlates of quitting include many of the factors that influence voluntary acts, but not,
according to the figure, drug exposure once drug use meets the criteria for dependence.
‘Thus, can we say that addiction is ambivalent drug use, which eventually involves more costs
than benefits (otherwise why quit?)’.
Behavioral choice principles predict ambivalent preferences, semi-stable suboptimal behavior
patterns, and the capacity to shift from one option to another. In contrast, the brain disease
account of addiction fails to predict the high quit rates; it fails to predict the correlates of
quitting, it fails to predict the temporal pattern of quitting, and it is tied to unsupportable
assumptions, such as the claims that neural adaptations, heritability, and irrationality are
evidence of disease. To be sure ‘compulsion’ and ‘choice’ can be seen as points on a
continuum, but the figure and research on quitting make it clear that addiction is not a
borderline case.
“It is time to think about addiction in terms of what the research shows, particularly the more
recent epidemiological studies, and it is time to abandon the medical model of addiction. It
does not fit the facts. The matching law, melioration, and hyperbolic discounting predict that
drugs and similar commodities will become the focus of destructive, suboptimal patterns of
behavior. These same choice models also predict that individuals caught in a destructive
pattern of behavior retain the capacity to improve their lot and that they will do so as a
function of changes in their options and/or how they frame their choices. This viewpoint fits
the facts of addiction and provides a practical guide to measures that will actually help addicts
change for the better”.
3
TASK 4 – VERSLAVING IS EEN KEUZE
ADDICTION AND CHOICE THEORY: THEORY AND NEW DATA
Bron: Heyman (2013)
Research shows that addiction has the highest remission rate of any psychiatric disorder, that
most addicts quit drugs without professional help, and that the correlates of quitting are those
that attend most decisions, such as financial and familial concerns. However, addiction is
‘disease-like’ in the sense that it persists even though on balance its costs outweigh the
benefits (e.g. most addicts eventually quit). In order to explain addiction, we need an account
of voluntary behavior that predicts the persistence of activities that from a global bookkeeping
perspective are irrational.
Likelihood of remission and time course of addiction
The figure shows the cumulative frequency of remission as a function of the onset of
dependence in a nation-wide representative sample of addicts. On the x-axis is the amount of
time since the onset of dependence. On the y-axis is the cumulative frequency of remission,
which is the proportion of individuals who met criteria for lifetime dependence but for the
past year or more had been in remission.
The cumulative frequency of remission
increased each year for each drug. By year 4
since the onset of dependence, half of those who
were ever addicted to cocaine had stopped using
cocaine. For marijuana, the half-life dependence
was 6 years, and for alcohol, the half-life
dependence was 16 years.
The graph also shows that there is much individual variation; among cocaine users, about 5%
continued to meet the criteria for addiction well into their 40s, among marijuana users, about
8% remained heavy users well into their 50s, and for alcoholics, more than 15% remained
heavy drinkers well into their 60s.
Correlates of quitting and the role of treatment
The correlates of quitting include the absence of additional psychiatric and medical
problems, marital status (singles stay addicted longer), economic pressures, fear of judicial
sanctions, concern about respect from children and other family members, worries about the
many problems that attend regular involvement in illegal activities, more years spent in
school, and higher income. Addicts often say that they quit drugs because they wanted to be a
better parent, make their own parents proud, and not further embarrass their families.
1
, GGZ3025 Verslaving
Disease etiology for persistent self-destructive drug use
The authors state that it ‘seems fair to say that who cites selfishness and myopic choices as
evidence of pathology (e.g. she has to be sick because she bought drugs rather than groceries)
naively misread human nature’. Behavioral psychologists and economists have discovered
principles that predict self-defeating, selfish patterns of behavior, including hyperbolic
discounting, melioration and the matching law. These are laws of choice that predict how
someone choices between different commodities and activities. Under some condition, they
predict relatively stable suboptimal patterns of behavior. General principles that apply to
everyday choices also predict compulsive-like consumption patterns in addictions.
These choice laws reflect a basic property of most choices; there is more than one ‘optimal’
strategy. One is optimal from the perspective of the most immediate circumstances, such as
the current values of the options. The others are optimal in terms of wider time horizons and
the perspectives of others. For example, in settings in which current choices affect the values
of future options, it is possible for the current choice to be the worst long-term choice. Thus, it
is possible that the drug is the best choice when the frame of reference is restricted to the
current values of the immediately available options but the worst choice when the frame of
reference expands to include future costs and other people’s needs.
According to this account, persistent drug use reflects the workings of a local optimum,
whereas controlled drug use or abstinence reflects the workings of a global optimum. Put
somewhat differently, whether or not drug use persists depends on the factors that influence
decision making, particularly values that emphasize global as opposed to a local frame of
reference.
But drugs change the brain
As self-administered drug doses greatly exceed the circulating levels of their natural
analogues, persistent heavy drug use leads to structural and functional changes in the nervous
system. It is widely assumed that these neural adaptations play a causal role in addiction. In
support of this interpretation brain imaging studies often reveal differences between the brains
of addicts and comparison groups. however, these studies are cross-sectional and the results
are correlations. There are no published studies that establish a causal link. In principle then
it is possible to hypothesize that drug-induced neural changes play little or no role in the
persistence of drug use.
First, most addicts quit, thus drug-induced neural plasticity does not prevent quitting. Second,
in follow-up studies, there were no increases in preference for cocaine. Third, the figure
(graph) shows that the likelihood of remission was constant over time since the onset of
dependence. Although this is a surprising result, it is not without precedent. A longitudinal
study of heroin addicts reports that the likelihood of going off drugs neither increased nor
decreased over time, and a study in rats reports that the probability of switching from cocaine
to saccharin was independent of past cocaine consumption. Since drugs change the brain,
these results suggest that the changes do not prevent quitting, and the slope of the figure
implies that drug-induced neural changes do not even decrease the likelihood of quitting
drugs once dependence is in place.
2
, GGZ3025 Verslaving
But there is a genetic predisposition for addiction
Studies have repeatedly demonstrated a genetic predisposition for alcoholism, and other
studies on heroin, cocaine and marijuana suggest the same. However, all behavior has a
genetic basis, including voluntary acts. Thus, there is no necessary connection between
heritability and compulsion. The relevance to addiction is that a genetic predisposition is not a
recipe for compulsion, just as brain adaptations are not a recipe for compulsion.
Summary
Most addicts quit using drugs at clinically significant levels, they typically quit without
professional help, and in the case of illicit drugs, they typically quit before the age of 30. The
correlates of quitting include many of the factors that influence voluntary acts, but not,
according to the figure, drug exposure once drug use meets the criteria for dependence.
‘Thus, can we say that addiction is ambivalent drug use, which eventually involves more costs
than benefits (otherwise why quit?)’.
Behavioral choice principles predict ambivalent preferences, semi-stable suboptimal behavior
patterns, and the capacity to shift from one option to another. In contrast, the brain disease
account of addiction fails to predict the high quit rates; it fails to predict the correlates of
quitting, it fails to predict the temporal pattern of quitting, and it is tied to unsupportable
assumptions, such as the claims that neural adaptations, heritability, and irrationality are
evidence of disease. To be sure ‘compulsion’ and ‘choice’ can be seen as points on a
continuum, but the figure and research on quitting make it clear that addiction is not a
borderline case.
“It is time to think about addiction in terms of what the research shows, particularly the more
recent epidemiological studies, and it is time to abandon the medical model of addiction. It
does not fit the facts. The matching law, melioration, and hyperbolic discounting predict that
drugs and similar commodities will become the focus of destructive, suboptimal patterns of
behavior. These same choice models also predict that individuals caught in a destructive
pattern of behavior retain the capacity to improve their lot and that they will do so as a
function of changes in their options and/or how they frame their choices. This viewpoint fits
the facts of addiction and provides a practical guide to measures that will actually help addicts
change for the better”.
3
