How well the mind remembers and what part of the brain is involved in memory formation depends on whether the words being memorized are emotionally arousing.

For the study, Elizabeth Kensinger, a researcher in MIT's Department of Brain and Cognitive Sciences, and Suzanne Corkin, professor of behavioral neuroscience in the same department, asked 14 men and 14 women to "learn" 150 words related to events, while the participants brains were being scanned in an fMRI (functional magnetic resonance imaging) procedure. Some of the words represented arousing events, such as "rape" or "slaughter." Others were nonarousing, such as "sorrow" and "mourning."

They then tested the participants to see which of the words they remembered having been shown. Kensinger and Corkin found that Mb

"This result suggests that stress hormones, which are released as part of the response to emotionally arousing events, are responsible for enhancing memories of those events," said the researchers. "We think that detailed cognitive processing may underlie the enhanced memory for the nonarousing events."

Memory storage can be enhanced by associating memories with emotionally exciting events. But use of such a technique raises a question that one ought to ponder before trying to learn important material while, say, scaring oneself watching a scary movie: Do you want various memories to be stored in areas of the brain associated with strong emotional reactions? Doing so may make the memories easier to recall but will also probably cause emotional reactions upon recall. Sometimes it makes sense to place memories where they will be linked to various emotional reactions. But in other cases it makes more sense to be able to retrieve some memories without having to feel a potentially stressful and draining emotional reaction.

It would be useful to be able to measure the intensity and type of emotional reactions as memories are recalled. Then it would be even more useful to be able to it would be useful to be able to disconnect the recall of a particular set of memories with the evocation of an undesired emotional reaction.

This result is not surprising either intuitively or based on previous scientific results. Also see my previous post Gory Pictures Improve Memory Retention.