Background: Emotions and Memory

Most people know from experience that memories are more readily and vividly recalled when there is a strong emotional component attached to them. In fact, one of the functions of emotions is to give significance to certain memories, to help ensure that important things are not forgotten.

In the brain, structures that make up emotional circuits are closely connected to the structures that are involved in forming memories. When emotional brain circuits are activated by strong emotions such as love or fear, they trigger a chemical response in the brain cells that form memory, causing the connections between memory cells to be strengthened. Of particular importance in this process is a component of the emotional brain known as the amygdala.

The amygdala is connected to one of the key structures in memory formation, the hippocampus. While much is known about the role the hippocampus plays in memory, very little is known about the role of the amygdala in the emotional enhancement of memory in aging and dementia. It is known that the amygdala is one of the first brain structures to be damaged in Alzheimer's Disease, although the effects of this damage on emotional memory in Alzheimer's patients is unclear.

This study is designed to clarify the role of the amygdala and other emotional brain components in emotional memory, in both normal elderly people and people with early Alzheimer's Disease. By doing so, we hope to understand better the changes in memory that occur very early in Alzheimer's Disease, as well as changes (if any) seen in the normal aging process. To assess the effects of age on this system, we will also evaluate a group of young people without memory problems for comparison.