Thoughts on suppression

Abstract

For over two decades researchers have shown that there are unexpected consequences when
an individual actively tries to avoid certain thoughts. First, you will start thinking about the thought you are trying to avoid more. Second, if the thought is about a behaviour, you increase the likelihood of engaging in that behaviour. In short, avoidance makes you less able to control what you think and what you do. Further research is necessary to explore why thought avoidance is such a prolific self- control strategy when all available evidence points to its counterintuitive consequences

Full text

Thoughts on suppression: how trying not to think of an action might lead
you down that very path
James Erskine and George Georgiou
Abstract
For over two decades researchers have shown that there are unexpected
consequences when an individual actively tries to avoid certain thoughts. First,
you will start thinking about the thought you are trying to avoid more. Second, if
the thought is about a behaviour, you increase the likelihood of engaging in that
behaviour. In short, avoidance makes you less able to control what you think
and what you do. Further research is necessary to explore why thought
avoidance is such a prolific self-control strategy when all available evidence
points to its counterintuitive consequences.
How many times have you resisted thinking about something because
you were afraid you might do it? Something perhaps unthinkable, or merely
mildly wanton. For example, you may try not to think about an attractive co-
worker in an effort to avoid difficult entanglements, or you may try not to think
about crème brûlée when on a diet. But what are the consequences of these
avoidances? Do they work, or do they somehow propel us towards the very act
we are attempting to avoid?
This question has been posed before in the guise of classic literature.
For example Dostoyevsky’s work is replete with examples of ordinary people
who felt the urge to act in a certain way – the young man walking in the city
centre alone at night entertaining thoughts of visiting a prostitute that he finds
abhorrent. He suppresses these thoughts in an effort to avoid the act, yet
moments later he finds himself at the coquette’s door. These phenomena form
the focus of this article: we will review how thought suppression may lead us to
become our own worst enemy.
Early work on thought suppression
Thought suppression commonly refers to the act of deliberately trying to
rid the mind of unwanted thoughts (Wegner, 1989). In early investigations
researchers demonstrated that the suppression of a particular thought often
resulted in the subsequent increased return of the unwanted thought, a
phenomenon termed the ‘rebound effect’ (Wegner et al., 1987). This basic
effect has been replicated on many occasions, and a more recent meta-analysis
suggests the rebound effect is robust (Ambramowitz et al., 2001; Wenzlaff &
Wegner, 2000). Therefore, there is currently a general acceptance of the view
that thought suppression does not work as a strategy for controlling one’s mind,
and if anything makes one more susceptible to unwanted intrusive thoughts. For
example, after watching a disturbing news item, I may attempt to suppress
thoughts about this disturbing footage. However, the likely outcome of this will
be that I will think about the footage more not less, and I may even begin to feel
obsessed (Markowitz & Purdon, 2008). Indeed, because of the frequent

intrusiveness of formally suppressed thoughts, suppression has been implicated
in the potential maintenance and causes of a wide variety of mental health
issues such as post-traumatic stress disorder, obsessive compulsive disorder,
anxiety and depression (Erskine et al., 2007; Purdon, 1999; Wegner & Zanakos,
1994). In a related vein, Freud (1901/1990) in his classic book The
Psychopathology of Everyday Life described moments when people blurt out
things that they are trying to suppress. Critically he noticed that the suppression
(or repression in his terminology) was heavily implicated in these later acts of
vocal impulsivity.
Thought suppression and behaviour
Previous work has typically focused on the effects of thought
suppression on later levels of intrusion. However, few studies have investigated
what happens when someone suppresses a thought with an associated
behaviour, for example, thoughts about resisting another glass of wine or
spilling the hot coffee one is carrying. Critically, Baumeister and colleagues
have suggested that thought suppression is frequently used to avoid behaviours
as well as thoughts (Baumeister et al., 1994). The key question concerns
whether a person suppressing thoughts about a behaviour will paradoxically
become more likely to engage in that behaviour later. This question is important
as many instances of the use of thought suppression may be in the service of
behavioural goals rather than mental goals. For example, I suppress thoughts of
my attractive co-worker not to avoid thinking of her but to avoid acting on these
thoughts. Furthermore, thinking of crème brûlée is not in and of itself
dangerous; we suppress the crème brûlée to avoid coping with the difficult act
of not eating it. This question is significant because the proposed mechanism
responsible for the return of formerly suppressed thoughts should also make the
behaviour (if there is an associated behaviour) more likely.
Wegner’s (1994) ironic process theory suggests that when people try to
suppress thoughts this activates two distinct processes. First, it sets up an
operating process that tries to create the state of mind one wants. It therefore
acts to seek out contents that are in agreement with the desired state (i.e.
anything other than the suppressed item). This process is deemed to be
conscious and effortful, and it appears why thought suppression feels like hard
work. For example when suppressing thoughts of highly craved snack food, we
seek out other less dangerous thoughts to distract ourselves. However, Wegner
(1994) suggests that thought suppression also sets in operation another more
automatic process that he terms the monitoring process. This searches
continually for thoughts indicating that one has failed the suppression task.
Therefore, this process looks for the presence of the suppressed thought. This
has the paradoxical effect of sensitising the mind to the very thought one is
seeking to avoid, or in more cognitive terms it raises the activation level of the
suppressed thought. This is problematic because many studies have now
indicated that raising the accessibility of a concept by a variety of means makes
it more likely that that concept will spring to mind more frequently (Bargh, 1997)
and potentially be enacted (Bargh et al., 1996). Furthermore, several studies
have now indicated that thought suppression directly leads the suppressed item
to gain activation (Klein, 2007; Wegner & Erber, 1992).

In line with this argument, studies have reported that thought
suppression can have behavioural consequences. Thus, Macrae et al. (1994)
demonstrated that participants suppressing thoughts about a skinhead
subsequently chose to sit further away from a skinhead when offered a free
choice of seats relative to participants that had not previously suppressed. In
addition, in line with the ironic process theory, Wegner and colleagues have
demonstrated that trying to fall asleep quickly or relax under stress results in
these processes taking longer or one becoming more anxious (Ansfield et al.,
1996; Wegner et al., 1997). Furthermore, participants suppressing the urge to
move a pendulum in a certain direction reliably moved the pendulum in that
precise direction. In a related study, participants suppressing thoughts of over-
putting a golf ball made that error more often if also under simultaneous mental
load (Wegner et al., 1998).
These phenomena are not uncommon in everyday life. How many times
have you carried a tray of food or drink thinking whatever happens I must not
spill this, only to then redecorate the living room with it? These errors seem to
plague us and chastise us all the more so because we knew exactly what we
shouldn’t have done ahead of time. Thereby, it seems that the act of trying not
to, or suppressing invites one to do exactly the opposite (Wegner, 2009).
Although the studies discussed are useful behavioural demonstrations of
the phenomenon, the actions implicated were not highly consequential (unless
one is a golf professional). With this in mind, Erskine and colleagues set out to
investigate whether similar behavioural effects of thought suppression might be
found with highly consequential behaviours such as eating, smoking and
drinking. Would suppressing thoughts of food, smoking or drinking result in
greater subsequent enactment of these particular behaviours? Across four
studies these phenomena were reported. Thus, Erskine (2008) had participants
suppress thoughts of chocolate and then take part in a supposedly unrelated
taste preference task. Importantly participants that had previously suppressed
chocolate thoughts went on to consume significantly more chocolate than the
control group that had not previously suppressed. Erskine and Georgiou (2010)
replicated these findings, while showing that participants high on restrained
eating (commensurate with a chronic tendency to diet) demonstrated the
behavioural rebound whereas participants low on restraint did not. Thus, the
very participants likely to use thought suppression (chronic dieters) were also
those most susceptible to behavioural rebound effects.
In a more recent study Erskine et al. (2010) examined the effects of
trying not to think about smoking on the number of cigarettes subsequently
consumed. Participants kept a diary for three weeks of the number of cigarettes
smoked per day. During weeks 1 and 3 all participants merely monitored their
intake. In week 2 one third suppressed thoughts of cigarettes, one third actively
thought about smoking (expression group) and the final third just monitored
without suppressing or expressing. Critically all participants were told not to
attempt to alter their behaviour during any week but to smoke as they normally
would. Results showed that for the expression and control group the number of
cigarettes smoked did not vary across the weeks. For the suppression group
the number of cigarettes smoked rose significantly in the week following
suppression. Importantly, we also have preliminary data showing a similar
naturalistic effect of suppressing thoughts of alcohol.

In a related study examining the links between different types of
behaviour, Palfai and colleagues (1997) examined the effects of suppressing
thoughts of alcohol on later smoking behaviour, as these behaviours are
frequently linked. Results indicated that suppressing alcohol resulted in
participants smoking more intensively – taking greater puffs and of a longer
duration, relative to participants that had not suppressed. This shows that
suppression of a particular thought can also result in an increase in the enacting
of an associated behaviour.
Other studies indicate that the effects of thought suppression may also
affect sexual behaviour. Thus, Johnston et al. (1997) investigated the
suppression of sexual thoughts in sex offenders of two types – preferential child
molesters and situational child molesters. Preferential child molesters are those
that show a definite preference for sexual relations with children, while
situational child molesters are those that do not necessarily prefer children but
who engage in sexual relations with minors for other reasons. Critically,
Johnston, Hudson and Ward (1997) showed that preferential sexual offenders
that suppressed sexual thoughts demonstrated post-suppression
hyperaccessibility of thoughts relating to child molestation, whereas situational
child molesters or non-molesters did not. This is important because as we have
already seen hyperaccessibility following thought suppression can make
thinking and acting more likely. These findings may explain the often surprising
incidence of sexual offending among people least suspected of behaving in this
way, for example priests. They have generally spent years suppressing sexual
urges and thoughts and this may in part explain some of the incidents of sexual
offending. In a further article Johnston Ward and Hudson (1997) argue that
using thought suppression in the treatment of sexual offenders may not be
appropriate.
The limitations of the effects of behavioural rebound
Whilst it seems that the effects of thought suppression on behaviour are
widespread it is premature to conclude that these are general effects of thought
suppression and that any suppressed thought linked to a behaviour may
rebound. Several sources of evidence suggest that in order to obtain
behavioural rebounds the suppressed thought must already be motivationally
interesting to the individual. For example, Erskine and Georgiou (2010) found
that behavioural rebounds with food-related thoughts may only occur in
participants that have a pre-existing tendency towards restrained eating
(indicating that they try to diet). Furthermore, although Erskine et al. (2010)
obtained behavioural rebound with smoking behaviour, all of the participants
were regular smokers for over one year, it therefore remains an open question
whether suppression of smoking thoughts in non-daily light social smokers
would ‘cause’ the same post-suppression smoking increase.
Importantly, two studies examining post-suppression hyperaccessibility
only demonstrated this in participants that reported previous motivational
tendencies towards the behaviour in question. Thus, Klein (2007) found
hyperaccessibility following suppression of alcohol thoughts in abstinent
alcoholics but not in non-alcoholics. Furthermore, Johnston, Hudson and Ward
(1997) reported hyperaccessibility to sexual and child-related concepts in
preferential child molesters, but not in situational child molesters or non-sexual

offenders. If the mechanism that causes behavioural rebound to occur is a
result of the hyperaccessibility caused by prior suppression, the behaviour in
question may therefore need to be motivationally interesting to the individual
before they suppress in order to cause behaviour rebounds. This is important as
it suggests that the people most susceptible to behaviour rebounds may well be
the people most likely to attempt to control themselves via these means,
because they realise that they are attracted to things that they want to avoid.
Effects of thought suppression on one’s perception of actions
One final note needs to be made of thought suppression effects and
time. Mostly, you suppress a thought, then get on with something else and the
suppressed thought returns later. The results with behaviour mirror this pattern -
you suppress a thought linked to a behaviour and the behaviour rebounds later.
This is particularly pernicious, as it does not allow individuals to notice the
causal significance of thought suppression in the later occurrence of the
rebounded behaviour. For example, if I close a door and at the same time a
light comes on in the room, I may perceive my closing of the door to have
caused the light to go on, even though I know that the two objects are not
usually causally related. Yet with thought suppression the return of the
suppressed thought or behaviour happens after the suppression has finished,
which does not allow me to see how my prior act of suppression has ‘caused’
the later return.
One other finding of note in the thought suppression literature suggests
that thought suppression can also affect what people perceive as having
caused the action that they have performed. Thus, Wegner and Erskine (2003)
had participants perform simple everyday actions, such as lifting a brick, while
either thinking about the action, suppressing thinking about the action, or
thinking about anything they wished. Critically when participants thought about
the action while doing it they felt like they had acted more wilfully and caused
the action to a greater degree. When they suppressed thinking about what they
were doing they reported feeling like the action was not caused by them but just
happened. There lies the rub of thought suppression: it seems a particularly
dangerous way to attempt to control yourself.
Overcoming the behavioural effects of thought suppression
Importantly, the research does suggest several promising avenues for
minimising the potential negative behavioural effects of thought suppression.
Firstly, one must avoid using thought suppression in instances where one is
attempting to control a behaviour. This is especially pertinent when attempting
to control behaviours such as smoking, excessive alcohol or food intake, as
these are likely areas where thought suppression will feature as a control
strategy. For example Erskine and Georgiou (2010) and Erskine et al. (2010)
demonstrated that thinking about chocolate or smoking (respectively) did not
lead to greater subsequent consumption, whereas suppression did. This
suggests that contrary to intuition, thinking about an act might not be as
dangerous as we feel. Secondly, the fact that suppression seems to interact
with one’s pre-existing motivational tendencies seems to imply that one should
become more aware of their danger areas. For example, the research from
Klein (2007) and Johnston, Hudson and Ward (1997) suggests that only people

who are motivationally predisposed to a particular behaviour will show
hyperaccessibility following suppression. Therefore, it is vital that these findings
are investigated further as they identify which individuals (and under what
circumstances) are more susceptible to behavioural effects following thought
suppression. Once one becomes aware of one’s danger areas it is important to
again seek to avoid using suppression. Importantly, research is starting to
examine potential ways to enable individuals to reduce their reliance on thought
suppression as a coping strategy. Most promising among these methods is
mindfulness meditation that focuses on accepting rather than avoiding certain
thoughts. Studies have already demonstrated that using mindfulness meditation
leads to reductions in the use of thought suppression and better control over
certain behaviours (Bowen et al., 2007).
In summary, research is converging on the view that thought suppression can
lead you to undertake actions that you were deliberately seeking to avoid.
Worse still, it can make you feel as though the act happened without ‘you’
intending. We believe that this vital research domain needs further emphasis
due to its high potential to explain the many occasions of everyday life where
we seem to act against our own best interests.
James A.K. Erskine is in the School of Population Health Sciences and
Education, St George’s, University of London
George J. Georgiou is in the School of Psychology, University of
Hertfordshire
References
Abramowitz, J.S., Tolin D.F. & Street, G.P. (2001). Paradoxical effects of
thought suppression. Clinical Psychology Review, 21, 683–703.
Ansfield, M.E., Wegner, D.M. & Bowser, R. (1996). Ironic effects of sleep
urgency. Behaviour Research and Therapy, 34, 523–531.
Bargh, J.A., Chen, M. & Burrows, L. (1996). Automaticity of social behaviour:
Direct effects of trait construct and stereotype activation on action. Journal of
Personality and Social Psychology, 71, 230–244.
Bargh, J.A. (1997). The automaticity of everyday life. In R. S. Wyer Jr. (Ed.) The
automaticity of everyday life (Advances in Social Cognition, vol.10). Mahwah,
NJ: Lawrence Erlbaum.
Baumeister, R.F., Heatherton, T.F. & Tice, D.M. (1994). Losing control: How
and why people fail at self-regulation. London: Academic Press.
Bowen, S., Witkiewitz, K., Dillworth, T.M. & Marlatt, G.A. (2007). The role of
thought suppression in the relation between mindfulness meditation and alcohol
use. Addictive Behaviour, 32, 2324–2328.

Erskine, J.A.K. (2008). Resistance can be futile: Investigating behavioural
rebound. Appetite, 50, 415–421.
Erskine, J.A.K. & Georgiou, G.J. (2010). Effects of thought suppression on
eating behaviour in restrained and non-restrained eaters. Appetite, 54, 499–
503.
Erskine, J.A.K., Georgiou, G.J. & Kvavilashvili, L. (2010). I suppress therefore I
smoke. Psychological Science, 21, 1225-1230.
Erskine, J.A.K., Kvavilashvili, L. & Kornbrot, D.E. (2007). The predictors of
thought suppression in young and old adults. Personality and Individual
Differences, 42, 1047–1057.
Freud, S. (1990). The psychopathology of everyday life. London: Norton.
(Original work published 1901)
Johnston, L., Hudson, S.M. & Ward, T. (1997). The suppression of sexual
thoughts by child molesters: A preliminary investigation. Sexual Abuse: A
Journal of Research and Treatment, 9, 303–319.
Johnston, L., Ward, T. & Hudson, S.M. (1997). Deviant sexual thoughts: Mental
control and the treatment of sexual offenders. Journal of Sex Research, 34,
121–130.
Klein, A.A. (2007). Suppression-induced hyperaccessibility of thoughts in
abstinent alcoholics: A preliminary investigation. Behaviour Research and
Therapy, 45, 169–177.
Macrae, C.N., Bodenhausen, G.V., Milne, A.B. & Jetten, J. (1994). Out of mind
but back in sight: Stereotypes on the rebound. Journal of Personality and Social
Psychology, 67, 808–817.
Markowitz, L.J. & Purdon, C. (2008). Predictors and consequences of
suppressing obsessions. Behavioural and Cognitive Psychotherapy, 36, 179–
192.
Palfai, T.P., Colby, S.M., Monti, P.M. & Rohsenow, D.J. (1997). Effects of
suppressing the urge to drink on smoking topography. Psychology of Addictive
Behaviors, 11, 115–123.
Purdon, C. (1999). Thought suppression and psychopathology. Behaviour
Research and Therapy, 37, 1029–1054.
Wegner, D.M. (1989). White bears and other unwanted thoughts. New York:
Viking/Penguin.
Wegner, D.M. (1994). Ironic processes of mental control. Psychological Review,
101, 34–52.

Wegner, D.M. (2009). How to think, say, or do precisely the worst thing for any
occasion. Science, 325, 48–51.
Wegner, D.M., Ansfield, M.E. & Pilloff, D. (1998). The putt and the pendulum:
Ironic effects of the mental control of action. Psychological Science, 9, 196–199.
Wegner, D.M., Broome, A. & Blumberg, S.J. (1997). Ironic effects of trying to
relax under stress. Behaviour Research and Therapy, 35,
11–21.
Wegner, D.M. & Erber, R. (1992). The hyperaccessibility of suppressed
thoughts. Journal of Personality and Social Psychology, 63, 903–912.
Wegner, D.M. & Erskine, J.A.K. (2003). Voluntary involuntariness.
Consciousness and Cognition, 12, 684–694.
Wegner, D.M., Schneider, D.J., Carter, S. & White, T. (1987). Paradoxical
effects of thought suppression. Journal of Personality and Social Psychology,
53, 5–13.
Wegner, D.M. & Zanakos, S. (1994). Chronic thought suppression. Journal of
Personality, 62, 615–640.
Wenzlaff, R.M. & Wegner, D.M. (2000). Thought suppression. Annual Review of
Psychology, 51, 59–91.