To improve the efficacy of addiction treatments it is important to understand the learning and behavioural processes involved. The experimental work presented here aims to further our understanding of the behaviour and related brain activity of smokers, using a range of experimental paradigms and Electroencephalographic (EEG) techniques. A range of behavioural tasks adapted from the animal literature for use with humans, were utilised to explore the choices made by smokers and the effect of smoking-related cues on drug-seeking behaviour. Tasks included concurrent choice and variations of the Pavlovian to Instrumental Transfer (PIT) task. EEG data was recorded during these experiments, and analysed using Event Related Potential (ERP) and frequency measures, to identify a neural component related to these effects. Resting EEG data was also collected and analysed to investigate the relationship between EEG frequency measures and individual difference measures.
Behavioural results broadly replicated those found in both animal and human research; smoking related cues enhanced responding for smoking- related outcomes showing Pavlovian control of Instrumental behaviour. Extinction of the Pavlovian cues did not reduce instrumental responses in the transfer stage of a PIT task. However no ERP or frequency components were found that consistently correlated with these behavioural effects.
The resting EEG data showed higher beta levels (less desynchronisation) in those with longer histories of smoking (four years and over) suggestive of either sensitisation or the loss of inhibitory neural control in long term smokers.
In summary, the behavioural data adds support to a growing body of literature regarding the effects of cues on the behaviour of addicted individuals. More work and perhaps other techniques need to be utilised in order to explore the neural correlates of these behavioural effects and the resting data suggests a promising route for further research
