Do you have memories you wish you could hold
onto forever?
Do you sometimes feel like they’re getting
less vibrant?
That’s probably because our working memory
starts to decline as soon as our late twenties!
Oh my god it’s all downhill from here, isn’t
it?
But new neuroscience research says that electrical
stimulation could drastically improve our
memory performance.
Would you do it?
In case you hadn’t noticed, your brain is
a complicated place.
It has lots of different kinds of memory,
and working memory is the kind in charge of
remembering information that’s no longer
directly in front of you.
This can be the temporary preservation of
something that just happened or the retrieval
of something from your long-term memory.
It’s the part of your cognition that’s
essential for things like processing and understanding
language, logical and spatial reasoning, planning,
and—of course—remembering where you last
saw your car keys.
Our commonly accepted model for how working
memory works is that it’s the result of
coordination between different kinds of brain
waves.
Brain waves are the pulses of electrical activity
in your neurons, and those pulses can occur
at different frequencies, resulting in different
types of waves.
Gamma waves have a high frequency and are
associated with the storage and processing
of sensory information.
Theta waves have a longer-frequency, and are
associated with lots of different brain states,
from an engaged brain that’s actively monitoring
something to a brain during REM sleep.
And when your working memory is activated—say
you’re pulling a memory from long-term storage
because you’re looking back on a detail
from your wedding day—those two types of
waves couple and synchronize to build you
a sense-memory picture of the thing you’re
trying to remember.
They work in tandem to weave your memories
together.
As we get older, our brains change.
We may lose gray matter volume, our circulation
can get worse so our brains get less blood
and oxygen—there are lots of possible structural,
neurobiological changes.
Another change associated with aging is a
decrease in synchronization between regions
of the brain.
Whereas before you may have been able to recall
with perfect clarity the look on your spouses
face as you said "I do," as we get older,
researchers see brain waves start to pulse
out of sync—the coupling and synchronization
of brain waves gets off-beat—and details
like that may fade away.
And of course, working memory is important
for much more than reminiscing.
It’s required for daily life function—like
remembering where you keep the knives and
forks or retaining new information from a
doctor’s appointment—so once we start
to lose working memory like with age-related
dementia, we see a potential decrease in quality
of life and independence.
Makes sense we’d wanna improve that, right?
Now you can, for the low, low price of shocking
your brain with electricity!
It’s actually not as scary as it sounds:
this particular study used a non-invasive
electrical stimulation method called transcranial
alternating-current stimulation to—for lack
of a better word—zap the prefrontal and
temporal regions of the brain simultaneously.
This jumpstarted the off-beat gamma and theta
waves back into sync.
The result?
Before electrical stimulation, a group of
test subjects in their 60s and 70s performed
significantly worse on a visual working memory
task than subjects in their 20s.
After 25 minutes of electrical stimulation
delivered via star-trek-like headset, the
older adults caught up to the younger group—both
age groups performed the same on the task.
Their brains were basically zapped back in
time!
There was also a group of participants in
the younger group who performed worse than
their fellow young peers on the exercise.
After the same amount of electrical stimulation,
their performance on the task had also improved,
so y’know there’s hope!
Plus the improvements in cognitive performance
for the older group lasted for at least 50
minutes, which was the duration of the experiment,
so who knows!
Maybe the effects lasted even longer.
People may balk when they hear about electrical
stimulation of the brain.
It may call to mind electroshock therapy,
a rather blunt instrument used in the early
parts of the 20th century on patients with
psychosis or schizophrenia, often against
their will and without much demonstrable therapeutic
effect.
But while those early cases may be infamous
in the world of medical ethics, there are
now plenty more examples of safe and effective
electrical stimulation of the brain.
Doctors are now using transcranial alternating-current
stimulation (TACS)—the same technology used
in this memory study—or Transcranial direct
current stimulation (TDCS) to test treatments
for things like severe depression or to enhance
concentration.
While relatively safe in the context of a
controlled research environment, the hype
around the possibility of electrical stimulation
devices has led to a trend of consumer electronics—brain
stimulating ones—or even DIY brain stimulation
kits.
Which—it doesn’t take a genius to guess—is
not a good idea.
Do NOT try this at home because if you do,
you risk seriously messing up your head with
mood changes, or even inducing seizures.
This study and many others like it working
on what we call the ‘entrainment’ of brain
waves is just the very beginning of understanding
where and how memory function breaks down,
and what the long-term solutions might be—the
neuroscience community is just dipping its
toes into how we could put this into play
as a real-world treatment for the aging brain…preserving
your memories, and hopefully your quality
of life, for as long as you live.
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