hey there welcome back to life noggin
have you ever had that eerie feeling
that you're reliving a past experience
maybe you're traveling to New York City
for the first time and it feels
strangely familiar
or maybe you're experiencing it right
now when you think you've already
watched this video before spooky this
phenomenon is called deja vu which is
French for already seen historically
deja vu has been linked with epilepsy
and seizures in the brain but that
doesn't explain why people without
epilepsy experience deja vu after all
about two-thirds of the population have
experienced that at least once in their
lives so there has to be something else
going on here the exact cause of deja vu
is unknown but there are a lot of
theories attempting to explain it for
simplicity's sake let's narrow down to
three main categories the first of these
is called dual processing this is when
two normally coordinated cognitive
processes become momentarily out of sync
for example if I feel familiar with
something it might be because my brain
has retrieved a memory similar to that
one that I'm currently experiencing
retrieving a memory always comes before
the familiarity well except in deja vu
in that case I would have a feeling
overhauling something without my brain
actually doing any retrieving I could
feel like I recognized something on that
street corner in New York City without
ever having been there before the next
theory is related to the nervous system
not functioning properly deja vu could
be caused by a spontaneous firing of a
neuron or from a delay in the neurons
transmission speed to demonstrate the
second one let's take a look at this
alpaca walking in high heels
now you've more than likely never seen
an alpaca do that before if you have I'm
very jealous of you but if you were
experiencing deja vu one explanation is
that the information passing through
your eyes into your brain is reaching in
at different times let's say the
information gets from your left eye to
your visual cortex just before the
information from your right eye gets
there these two events happen in such a
short amount of time that the left eyes
information is not stored as memory yet
but since your brain received the
information twice it feels familiar
nonetheless the last theory is a bit
more intuitive and states that if you
have a false sense of familiarity with
something new it's because some elements
of the situation are familiar for
example if you were to go to a new
friend's home for the first time and
they have the same kitchen table as your
great-aunt you may have a strong feeling
of familiarity without realizing where
you've seen it before in your confusion
you mistakenly think that you must have
experienced the entire situation already
instead of just the table well then why
don't we experience deja vu every time
we subconscious
they recognize something some theories
say that there may have to be multiple
elements that are familiar to you or
maybe the room just has to be organized
in a similar way as the one you
recognize either way something is
familiar and you just haven't realized
it yet have you ever experienced deja vu
and tell us out of all these which
theory sounds the most convincing to you
if you want even more life noggin check
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I'm black oh this has been life noggin
don't forget to keep on thinking