Dreams, Trauma, and Prediction Errors

It is widely known that dreams can be strongly affected by traumatic events, but there may be other ways in which dreams relate to trauma. In this paper, we argue that different types of dreams could both contribute to trauma and alleviate it according to the prediction errors that occur either in dreams or in response to them after waking. A prediction error occurs when an experience contradicts one’s expectation and it is often accompanied by surprise. Prediction errors are involved in memory updating processes that can be long-lasting. Not only nightmares but also unpleasant, and surprisingly, even neutral and pleasant dreams have the potential to contribute to trauma, affecting our waking lives in a similar way to waking traumatic experiences. We postulate that certain dreams can also be beneficial for trauma alleviation. Further, clinical evidence suggests that working with prediction errors that occurred in dreams and during our response to dreams after waking can assist in alleviating the negative effects of trauma.