Decreased Rostral Cingulate Zone Cue-reactivity to Unhealthy Stimuli after Avoidance Training in Healthy Participants

The Approach and Avoidance Task (AAT)-training has been established as a promising treatment add-on, capable of reducing relapse rates in addiction. First neuroscientific research in people with alcohol use disorder has linked nucleus accumbens (NAc), amygdala, medial prefrontal cortex (mPFC), and dorsolateral prefrontal cortex (dlPFC) brain activity to the AAT. The present study was the first to investigate AAT-induced changes in brain function among healthy participants. We assumed that reward-related structures such as the NAc and the mPFC would play a minor role, while the amygdala and motor areas were thought to be more important in such a sample. To test this, 62 participants were randomly assigned to an AAT-training group or a control group, receiving sham-training. We employed an implicit AAT-training, aimed at changing beverage consumption by avoiding 90% of unhealthy and approaching 90% of the healthy beverages. FMRI data, acquired during a cue reactivity and a Go/No-Go paradigm, was used to compare pre- and post-training activation. No differences in beverage consumption in a bogus taste test and regular consumption during two weeks after the intervention were found. On the neural level, the experimental group showed less rostral cingulate zone (RCZ) activity in response to unhealthy drinks after the training. The RCZ has been associated with action selection and decreased activity suggests that relatively automatic action-outcome associations became established through avoidance training. More speculatively, a devaluation process, assigning less subjective value to the avoided stimuli, might have occurred. Reasons for the failure to find behavioural effects are discussed

The Role of Response Inhibition in the Approach and Avoidance Task: No Evidence for Approach and Avoidance Task-training effects in Inpatients with Alcohol-Use Disorder

The Approach and Avoidance Task (AAT) has been shown effective in reducing relapse rates among patients with alcohol-use disorder and thus can enhance treatment outcome. However, until now the working mechanisms of the AAT are poorly understood. An intriguing possibility is that response inhibition, as a predominantly reflective process, might play a more pronounced role in AAT-paradigms than commonly thought. The present study was the first to disentangle the role of response inhibition and avoidance gestures in AAT-trainings. To this end, 76 inpatients with alcohol-use disorder undergoing detoxification treatment were randomly assigned to either a classical AAT-, an inhibition AAT-, or a sham-training group. During the intervention participants in the classical AAT group had to avoid pictures related to alcohol, while participants in the inhibition AAT group were requested to inhibit a response when alcohol-related content was presented. Training lasted for 3 weeks and alcohol consumption and alcohol approach biases were assessed both before and after the intervention and another nine weeks later. AAT-training effects, such as decreases in alcohol consumption and/or alcohol approach biases, were not replicated. Neither was the inhibition AAT-training effective. Reasons for the observed results are discussed in detail