This is a synopsis of a talk given by Dr Jon May, Senior Lecturer in Psychology at the University of Sheffield at the British Association of Science Festival at the University of Salford in September. It suggests that there may be techniques that could be used to reduce the desire for addictive substances in the form of displacement activities. 

The research was carried out on smokers (nicotine addicts) to see if anything could reduce their desire for cigarettes. The key finding of the research described was that craving for substances such as cigarettes can be reduced by giving people a mental imagery task to concentrate on. What is new and interesting about this work is that most ideas about addiction concentrate on the physiological aspects, and see addicts as literally helpless in the face of their bodily needs for a substance. The research shows that the subjective strength of cravings for cigarettes can be reduced by a simple mental task, potentially opening the way to psychological interventions that could be used to help people suppress their cravings for other drugs. The results suggest that these people can be helped to avoid relapse, effectively boosting their willpower.

The next step in the research is to show that reducing the subjective strength of cravings also reduces consumption - i.e. that the cravings are directly linked to behaviour. The background to this research is that addiction is often thought of as a physiological problem, that people are literally helpless to resist. Chemical pathways used by addictive substances have been identified, and drugs have been developed that interfere with them, in the aim of disrupting addictive processes. The feelings of craving that accompany addiction are seen as resulting from addiction, not that they themselves have a causal role in leading people to use substances. The power of mental states is recognised in drug interventions, for example even advocates of nicotine patches always say that they also 'require willpower'.

The team have developed a theory of the mental aspects of craving, the Elaborated Intrusion Theory. The thoughts and associations that external cues in the world, and internal cues in the body, trigger can break into awareness. When they do so, they are experienced as spontaneous Intrusive Thoughts, that apparently come into the mind out of the blue. The immediate mental sense is of the potential reward and relief that using the substance would provide. This motivates people to continue thinking about the substance, elaborating their thoughts by searching their memory and constructing mental images of the substance. Visual images of what it looks like and where it might be found contribute to cycles of reward and further elaboration, so that the craving comes to dominate the thoughts.

After a short time, though, the elaborated thoughts make addicts even more aware that they don't have the substance, and so become aversive as the sense of being without it grows and grows. This is the point at which many people's resistance cracks and they give in to their craving.

An experiment was tried on smokers who had abstained prior to the study. One group had to watch a screen full of black and white squares which randomly changed colour. Known as the flickery dots display, this has been shown in previous research to make mental imagery less vivid, and to interfere with memory tasks that require imagery. It was found that watching the flickery dots significantly reduced the cravings with respect to the abstaining smokers control group.

These results only show that the reported strength of cravings can be reduced, not that smokers actually went on to smoke less. If it can be confirmed that it actually affects behaviour, then it may be possible to develop a cheap and non-drug based intervention that can help provide people with the willpower necessary to quit smoking, and maybe also to stop using other addictive substances.