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Each month we review our poster and slide submissions and feature one as our ‘poster/slide of the month’. We were spoiled for choice in May, but decided on “Approach motivation in depression: a combined ESM and fMRI approach” to tie in with Mental Health Awareness Week, which took place during the month. This poster was presented at the 71st Society of Biological Psychiatry Annual Meeting 2016 by Natasha Bloodworth, Dr. Natalia Lawrence and Dr. Nicholas Moberly, of the University of Exeter.

The authors investigate approach motivation – desire to take action that will result in a positive outcome, avoiding any negative outcomes – in relation to symptoms of depression. They were keen to link lab findings to real-world experience, as behaviour and emotional responses observed in laboratory studies can have little relevance to those in everyday life. A technique called experience sampling (ESM) lends itself well as measures are completed many times in real-life settings, improving ecological validity and reducing vulnerability to recall bias.

Participants were given goals to pursue each day and asked about these tasks six times per day for a week. Some of the participants were asked to also take part in a rigged card guessing task and fMRI scans were acquired when they won and lost. Combining the data, the authors were able to examine the links between individual differences in goal motivation and affect, and brain activation. This provides some evidence that basic measures of brain function are relevant to everyday aspects of depression.

Several regions of interest in the brain were focused on,based on their known involvement in reward processing. These regions included the nucleus accumbens (NAcc), caudate nucleus, medial frontal cortex (MFC) and the putamen. The authors present the hypotheses that the results of the ESM study may correlate to activity in relevant regions:

• Lack of approach motivation will correlate with decreased activation of the NAcc, MFC and the putamen

• High levels of approach motivation will correlate with increased activation of the NAcc, MFC and the putamen

• Higher ESM ratings of positive affect, goal progress and goal effort will correlate with activation in the NAcc and caudate nucleus.

The study found that a lack of motivation did not significantly correlate with activation of the brain regions. Although this is inconsistent with previous findings, it may not be not fully comparable as the present sample were not clinically depressed.

Scores from the ESM study were positively correlated with activation in the left NAcc during anticipation of reward. This does support previous research where activation in reward areas was positively associated with trait measures of approach motivation. ESM measures also show positive correlation with activation in the left accumbens, when patients were experiencing positive affect. This provides evidence that there is some relevance to the everyday experience of affect.

The relationship between reward processing and motivation might not be as straightforward as first thought, as there were no significant correlations between ESM ratings of positive affect and goal progress with caudate activation.

This research may have some implications for the treatment of depression as it may provide some indication of which mechanisms would be most beneficial to focus on during treatment.