Online Foraging and Energy Conservation: Reward Manipulation.

Clinical depression frequently develops in response to unremittingly painful or stressful circumstances, and is often associated with feelings of exhaustion and energy depletion which can motivate behavioural withdrawal or avoidance. Limiting exploration in a harsh or unrewarding environment can be an adaptive strategy, but may have the unintended consequence of reducing access to new information that might signal a change in environmental contingencies, and therefore maintaining depression through the maintenance of negative beliefs and predictions. An additional unintended consequence of behavioural withdrawal is the loss of environmentally-occurring reward (enjoyable sensory stimulation, feelings of achievement on completing an activity, positive social interaction etc.) and this deprivation of reward may also contribute to depression maintenance. We have developed a foraging task which will allow us to study decision-making about resource conservation and its relation to explorative behaviour and reward learning. The task was previously tested in the lab in a considerable case-control sample made up of healthy and depressed participants. The task has now been adapted to be completed online, for ease of recruitment. With this study we aim to understand whether the task replicates the results on a larger, non-clinical sample and gain insight on specific analyses which had low power for the in-person experiment.