Does stress affect your memory Elizabeth Cox

You spend weeks studying
for an important test.

On the big day, you wait nervously
as your teacher hands it out.

You’re working your way through,
when you’re asked to define ‘ataraxia.’

You know you’ve seen it before,
but your mind goes blank.

What just happened?

The answer lies in
the complex relationship

between stress and memory.

There are many types
and degrees of stress

and different kinds of memory,

but we’re going to focus on
how short-term stress

impacts your memory for facts.

To start, it helps to understand
how this kind of memory works.

Facts you read, hear, or study

become memories through
a process with three main steps.

First comes acquisition:

the moment you encounter
a new piece of information.

Each sensory experience activates
a unique set of brain areas.

In order to become lasting memories,

these sensory experiences

have to be consolidated
by the hippocampus,

influenced by the amygdala,

which emphasizes experiences
associated with strong emotions.

The hippocampus then encodes memories,

probably by strengthening
the synaptic connections

stimulated during
the original sensory experience.

Once a memory has been encoded,

it can be remembered,
or retrieved, later.

Memories are stored all over the brain,

and it’s likely the prefrontal cortex
that signals for their retrieval.

So how does stress
affect each of these stages?

In the first two stages,

moderate stress can actually
help experiences enter your memory.

Your brain responds to stressful stimuli

by releasing hormones
known as corticosteroids,

which activate a process
of threat-detection

and threat-response in the amygdala.

The amygdala prompts your hippocampus

to consolidate the stress-inducing
experience into a memory.

Meanwhile, the flood
of corticosteroids from stress

stimulates your hippocampus,

also prompting memory consolidation.

But even though some stress
can be helpful,

extreme and chronic stress
can have the opposite effect.

Researchers have tested this by injecting
rats directly with stress hormones.

As they gradually increased
the dose of corticosteroids,

the rats’ performance on
memory tests increased at first,

but dropped off at higher doses.

In humans, we see a similar
positive effect with moderate stress.

But that only appears when
the stress is related to the memory task—

so while time pressure might
help you memorize a list,

having a friend scare you will not.

And the weeks, months, or even years

of sustained corticosteroids
that result from chronic stress

can damage the hippocampus

and decrease your ability
to form new memories.

It would be nice if some stress
also helped us remember facts,

but unfortunately, the opposite is true.

The act of remembering relies
on the prefrontal cortex,

which governs thought,
attention, and reasoning.

When corticosteroids
stimulate the amygdala,

the amygdala inhibits,
or lessens the activity of,

the prefrontal cortex.

The reason for this inhibition
is so the fight/flight/freeze response

can overrule slower, more reasoned
thought in a dangerous situation.

But that can also have
the unfortunate effect

of making your mind
go blank during a test.

And then the act of trying to remember
can itself be a stressor,

leading to a vicious cycle
of more corticosteroid release

and an even smaller chance of remembering.

So what can you do to turn stress
to your advantage

and stay calm and collected
when it matters the most?

First, if you know a stressful
situation like a test is coming,

try preparing in conditions similar
to the stressful environment.

Novelty can be a stressor.

Completing practice questions
under time pressure,

or seated at a desk
rather than on a couch,

can make your stress response
to these circumstances

less sensitive during the test itself.

Exercise is another useful tool.

Increasing your heart
and breathing rate

is linked to chemical changes
in your brain

that help reduce anxiety
and increase your sense of well-being.

Regular exercise is also widely
thought to improve sleeping patterns,

which comes in handy
the night before a test.

And on the actual test day,

try taking deep breaths to counteract
your body’s flight/fight/freeze response.

Deep breathing exercises have shown
measurable reduction in test anxiety

in groups ranging from
third graders to nursing students.

So the next time you find your mind
going blank at a critical moment,

take a few deep breaths
until you remember ataraxia:

a state of calmness, free from anxiety.