The relation between stress and memory
Stress hormones carry a message that tells other cells in our body what
to do. The first receivers of these messages are stress hormone
receptors. In addition, there are stress hormone receptors pretty much
everywhere in our body, including the brain.
Interestingly, the very brain areas that are responsible for our
learning and memory functions have the greatest number of stress hormone
receptors. We always have to keep in mind what our stress response
system was initially designed for: to help to ensure our survival.
The stress response system does this in several ways (i.e. making
sure we have enough energy to fight or flee in the face of a threatening
situation), but it also helps up to remember relevant details about
these situations so that we can avoid them in the future or be better
equipped to deal with them a second time.
For instance, if we had taken a different route back from the mammoth hunt and ended up in saber tooth tiger territory (and managed to
escape), we would need to remember the location of this territory and
the methods we used to get away. We managed to do this through the
action of stress hormones in brain areas critical for learning and
memory. Beautifully said!
In humans, three of the most important learning and memory regions
are the hippocampus, the amygdala, and the prefrontal cortex. Each of
these brain areas is highly specialized for specific types of memory
The hippocampus for instance is involved in spatial memory (i.e.
where the saber tooth tiger attack took place), the amygdala is involved
in emotional memory (i.e. the fear we felt at the time of the attack
that resulted in the release of stress hormones), and the prefrontal
cortex helps us to evaluate the situation in order to make decisions
about how to act (i.e. pay attention to only the relevant details
-tiger- and decide where to throw our spear).
These brain areas are all interconnected and talk to each other through several relay systems.