Hey there, Brainiacs!
I’m Alie Astrocyte,
and you’re watching Neuro Transmissions.
As most of you probably know,
I’m a graduate student.
I’m working on getting my PhD in neuroscience.
I love my research.
Getting to study astrocytes every day
is totally awesome!
So even though grad school can be
stressful sometimes, I love what I do.
Not all stress is bad.
Stress is actually an important
physical response that helps keep us sharp.
Short term stress can help improve
our alertness and memory.
It also motivates us on a daily basis.
But as I’ve learned, sometimes stress...
isn’t just stress.
When stress goes from being a motivator
to being totally overwhelming,
that’s not normal.
A couple years ago,
I was diagnosed with generalized anxiety disorder.
Generalized anxiety disorder
is described by the
Anxiety and Depression Association of America
as “persistent, excessive, and unrealistic
worry about everyday things”.
Basically?
I was worried.
All the time.
About everything.
Getting a diagnosis from a psychologist
was the first step to finding
a treatment plan that works for me.
Something I’m still navigating everyday.
And since I’m a neuroscientist,
I got curious about what anxiety
meant for my brain.
Anxiety disorders include
not only Generalized Anxiety Disorder,
but also other conditions like
social anxiety disorder, PTSD,
and panic disorder.
The National Institute of Mental Health says
that anxiety disorders are the most common
mental illness in the United States,
affecting nearly 1 in 5 adults.
So it’s pretty important for us to figure
out how these disorders work,
and how to treat them effectively.
Just like how the occipital lobe handles vision
and the temporal lobe processes sounds,
our emotional responses have
their own brain regions.
The limbic system is a complex set of structures
deep inside the brain that includes
the hippocampus, amygdala,
hypothalamus, and thalamus.
This circuit is believed to handle
most of our emotional processing,
and the prefrontal cortex is responsible for
integrating this emotional information into
our decision making.
Scientists think that anxiety disorders
pop up when there are changes in
the signaling of the limbic system.
Of course, we can’t go digging around in
living people’s brains to see how their
neurons are firing, but scientists can
study this theory using non-invasive
imaging techniques, like fMRI and PET scans.
This kind of research has found that
patients with anxiety disorders have
more activity than normal in the limbic system.
Importantly, there’s a trend for these patients
to have hyperactive amygdalas,
which is interesting, because
the amygdala is sometimes considered
the “fear center” of the brain.
Each disorder has its own quirks, too.
In panic disorder, the amygdala hyperactivity
might be caused by less GABA,
the main inhibitory neurotransmitter,
in some areas of the brain.
This could lead to less inhibitory signaling
in the emotion circuits, making it
harder to control panicky feelings.
Patients with generalized anxiety disorder
also seem to have larger amygdalas than controls.
So their brains have more machinery to
process fear information, which then
reacts more strongly to negative emotional stimuli.
PTSD, on the other hand, might be
a result of too much excitatory signaling
in the hippocampus and amygdala,
leading to intense emotional reactions
to triggering stimuli.
PTSD might be partially caused by
our logical brain regions being forced to
process emotional information,
giving our brain a harder time
controlling those thoughts.
In social anxiety disorder, being exposed
to images of faces leads to extra activity
in the amygdala.
So people who are anxious in social situations
are processing social information through
a layer of fear, making those environments
stressful for them.
Like in PTSD, this might be a result of
excessive excitatory signaling in the limbic system.
Researchers are still working out a lot of
the details on how differences in the brain
lead to these conditions.
The limbic system has a lot of parts,
and there’s a lot of variation in the symptoms
and severity of each of these disorders.
So it can be hard to pick apart the details.
For me, anxiety felt like having my stress dial
cranked up to eleven.
All the time.
These go to eleven.
I had trouble sleeping, and felt like I was
never on top of my to-do list.
It actually took me a really long time
to admit that how I felt wasn’t just
normal grad school stress.
And it wasn’t until I started getting treatment
that I realize just how bad I actually felt.
So how do we treat anxiety disorders?
I’ve personally found a combination of
cognitive behavioral therapy,
usually called CBT for short,
and medication to work the best for me.
Micah is going to talk about the
psychological causes of anxiety
and how therapies like CBT are used
to treat it in a separate video.
Medication can be helpful for
some patients, too.
The most common drugs prescribed for
anxiety disorders are
selective serotonin reuptake inhibitors,
or SSRIs,
which are also commonly prescribed for depression.
SSRIs function by inhibiting the reuptake
of serotonin, a neurotransmitter.
In the brain, serotonin is known to be involved
in mood, sleep, and appetite regulation.
SSRIs block neurons from reabsorbing serotonin
after it’s released, leaving it
lingering in the synapse,
where it can repeatedly stimulate the
receiving neuron and
push the neighboring neurons
to adjust their serotonin signaling.
SSRIs are used for long-term anxiety management.
It takes them a while to have an effect,
and they help keep moods balanced.
It’s not totally clear how SSRIs
help with anxiety disorders.
It’s not even totally clear how they work.
But they do seem to help.
Alternatives to SSRIs are
serotonin-norepinephrine reuptake inhibitors,
or SNRIs.
They have very similar effects,
but instead of just blocking
the reuptake of serotonin,
SNRIs block absorption of serotonin
and norepinephrine, also called noradrenaline.
This neurotransmitter is linked to
alertness, attention, and action-readiness.
Which medication a patient uses depends on
their preferences, and it can take a
couple of tries to find the right choice.
When patients are dealing with an acute crisis,
like a panic attack, short-term, fast-acting
medications like benzodiazepines may be
more practical.
These drugs have a sedative effect,
and act as muscle relaxants.
Unlike SSRIs and SNRIs,
benzodiazepines are considered addictive
because of their immediate relaxing effect,
and can be easily abused.
However it’s treated, there are a lot of
options out there for people dealing with
anxiety disorders.
Getting treatment has really changed
my life for the better, and I’m really grateful
that scientists and doctors have spent
so much time and effort trying to understand
these conditions so that people like me can
get the help we need.
Thanks for watching this episode of Neuro Transmissions!
If you liked it, please give it a thumbs up.
And hit subscribe to catch more
videos about brain diseases and disorders
in the future.
If you’re really excited to see
more videos like this,
consider supporting us on Patreon.
We couldn’t do all this without your support.
You can find me on Twitter @alie_astrocyte
if you’d like to know more about
my own experience with anxiety.
And if you’d like to learn about a
particular condition,
let us know in the comments!
Until our next transmission, I’m Alie Astrocyte.
Over and out!