Anticipation and the Recollection of Disturbing Emotional Events Closely Linked

Every single one of us must have experienced on his own the fact that disturbing or distressful happenings from the past remain more vivid in our memory than everyday simple actions and events.

Moreover, researchers at the University of Wisconsin-Madison found that anticipation plays a crucial role in the recollection of disturbing or fearful situations from the past. Also, anticipation does not only occur before a certain event or situation an individual has to face, but it can also occur afterwards, when the event is over.

For instance, take the case of a student who has stage fright and has to take an important oral exam in front of his teachers. Naturally, he will anticipate the moment of the oral examination before he enters the room where he is going to present his project. If things go wrong, the student will also bear the recollections of the tough experience in his mind and he is going to remember about the unfortunate event for many times after it is over.

The findings of the study are published in the Proceedings of the National Academy of Sciences. The main goal of the research was to understand how the memory of disturbing past events functions and to discover better treatment methods for conditions such as post-traumatic stress disorder (PTSD) or social anxiety. Both of these emotional disorders are triggered by extremely upsetting events which turn into traumas and come to haunt the memories of the patients over and over again.

"The main motivation for this study was a clinical one, in terms of understanding and applying knowledge about memory so that we can better inform the treatment of disorders that have a large memory component, like PTSD," noted lead author of the study, Kristen Mackiewicz.

Besides the fact that an individual is going to imprint in his memory certain distressing events from the past, he is also very likely to remember them before he has to face another similar situation. For instance, the stage fright student who failed his oral exam will always remember what happened in the past whenever he has to confront another such situation.

"Our study illustrates how the power of expectancy can extend to memory formation as well. Just the expectation of seeing something bad can enhance the memory of it after it happens," stated Jack Nitschke, an associate of UW-Madison's Waisman Laboratory for Brain Imaging and Behavior.

In the research, scientists used the functional magnetic resonance imaging technique to study the brains of 36 healthy individuals when facing a difficult situation. Researchers studied the volunteers' brain 30 minutes after they looked at two types of pictures: some neutral pictures and some illustrating very violent accidents, such as bloody confrontations, murders etc.

Scientists found that two main regions of the brain are stimulated when a person has to confront a stressful or disturbing event: the amygdala, playing an active part in the formation of emotional memories, and the hippocampus, which is crucial in helping the brain to form long-term recollections.

"We found that the more activated the amygdala and hippocampus had been during the anticipation of the pictures, the more likely it was that a person would remember more of them right away," said Nitschke.