Genius Foods

where you were the moment you heard of the 9/11 attacks
on the World Trade Center? I’ll bet that day is burned into
your memory in crystal-clear, stunning detail. This is owed
to none other than norepinephrine.
The main hub of norepinephrine is a small region in the
brain known as the locus coeruleus. Any stressful stimuli
lead to an increase in norepinephrine, from a terrorist attack
to a major fight with a significant other to simply not eating
for twenty-plus hours. Evolutionarily speaking, this is an
important adaptive function. For much of our time on the
planet, stressful stimuli required our immediate attention,
and detailed, long-lasting memories needed to be formed to
avoid such an event in the future (provided that we lived
through that initial encounter). This is called long-term
potentiation, and it plays an important role in fear
conditioning. Because norepinephrine has such a powerful
effect, undoing learned fear can be an intensive process—
ask anybody suffering from post-traumatic stress disorder,
or PTSD.
Milder forms of stress can also activate many of the
same pathways. The “stress” of learning a new instrument,
solving a crossword puzzle, or experiencing novelty—
exploring a new town, or going on a walk with changing
scenery, for example—all have been shown to increase
norepinephrine in the brain. This can be very beneficial, as
norepinephrine helps to make the connections between
neurons stronger.