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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