Thought suppression

Thought suppression is when an individual consciously attempts to stop thinking about a particular thought. It is often associated with obsessive–compulsive disorder (OCD). OCD is when a person will repeatedly (usually unsuccessfully) attempt to prevent or "neutralize" intrusive distressing thoughts centered on one or more obsessions. It is also related to work on memory inhibition. Thought suppression is relevant to both mental and behavioral levels, possibly leading to ironic effects that are contrary to intention.

When an individual tries to suppress thoughts under a high cognitive load, the frequency of those thoughts increases and becomes more accessible than before. Evidence shows that people can prevent their thoughts from being translated into behavior when self-monitoring is high; this does not apply to automatic behaviors though, and may result in latent, unconscious actions. This phenomenon is made paradoxically worse by increasing the amount of distractions a person has, although the experiments in this area can be criticized for using impersonal concurrent tasks, which may or may not properly reflect natural processes or individual differences. Ironic process theory is one cognitive model that can explain the paradoxical effect seen above. However, given the mixed evidence and commensurate with the latest research, it is suggested that such a model needs to account for individual differences. It should also note possible neurological dynamics (see, for instance, obsessive–compulsive disorder), to be considered robust.

In order for thought suppression and its effectiveness to be studied, researchers have had to find methods of recording the processes going on in the mind. One experiment designed with this purpose was performed by Wegner, Schneider, Carter & White. They asked participants to avoid thinking of a specific target (e.g. a white bear) for five minutes, but if they did, they were told then to ring a bell. After this, participants were told that for the next five minutes they were to think about the target. There was evidence that unwanted thoughts occurred more frequently in those who used thought suppression compared to those who were not. Furthermore, there was also evidence that during the second stage, those who had used thought suppression had a higher frequency of target thoughts than did those who hadn't used thought suppression; later coined the rebound effect. This effect has been replicated and can even be done with implausible targets, such as the thought of a "green rabbit". From these implications, Wegner eventually developed the "ironic process theory".

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