The effect of trauma on feedback processing

The cognitive impact of psychological trauma can manifest as a range of posttraumatic stress symptoms that are often attributed to impairments in learning from positive and negative outcomes, aka reinforcement learning. This study aimed to circumscribe the impact of psychological trauma on reinforcement learning in the context of neural response in time and frequency domains. Two groups of participants were tested- those who had experienced psychological trauma and a control group who had not- while they performed a probabilistic classification task that dissociates learning from positive and negative feedback during a magnetoencephalography (MEG) examination. While exposure to trauma did not affect learning accuracy or response time for positive or negative feedback, MEG cortical activity was modulated in response to positive feedback.

Analysis of the time-frequency domain revealed heightened activity in theta and alpha frequency bands (4–10 Hz) in the lOFC in the trauma group. Moreover, by dividing the two groups according to their learning performance, the activity for the non-learner subgroup was found to be lower in lOFC and higher in the supramarginal cortex. These differences were found in the trauma group only. The results highlight the localisation and neural dynamics of feedback processing that could be affected by exposure to psychological trauma. This approach and associated findings provide a novel framework for understanding the cognitive correlates of psychological trauma in relation to neural dynamics in the space, time, and frequency domains.

Origional publication: The effects of trauma on feedback processing: an MEG study