Encoding - Emotion

Emotion is closely linked with learning and memory. Researchers have found that new information enters the brain through the limbic system, the seat of our emotions, and is then passed to sites within the cerebral cortex for long term retention. Long term retention is thought to be accomplished by the hippocampus formation of memory traces, or engrams.

The amygdalae of the limbic system are responsible for regulating emotional response and, importantly, for attaching emotional significance to incoming sensory stimuli. Dr. L. Cahill, Center for the Neurobiology of Learning and Memory at the University of California Irvine, postulates that the limbic system weights information for storage so that the strength of a memory is roughly proportional to its importance.*

For learning to occur efficiently, there must be just the right amount of emotion applied as a function of stress hormones (adrenaline). If there is too little, the material to be learned will be ignored. If there is too much, emotional arousal will block new learning. When activated, the stress hormones cause the well-known "fight or flight" response. This activation also provides information to the amygdalae of the emotional charge of the just experienced event. The interaction between stress hormones and the amygdalae influences what is stored in memory.*

This is what underlies the phenomenon of "Flashbulb Memories." These are memories of highly, emotionally charged events--usually unanticipated events--that seem to automatically become vividly engraved in detail in memory with no conscious effort. Examples are remembering where you were on 9/11 or during the Challenger disaster.

Challenger Space Shuttle (NASA)	fMRI of Amygdalae (NIMH)
Unanticipated, emotionally charged events can create vivid, detailed "Flashbulb Memories."

*Emotions and Memory, Radio National, the Health Report, interview by Norman Swan of Dr. Larry Cahill.