Hi, my name is [? Veneta. ?] I live in Acton, Massachusetts
and I am in grade five.
My question today is, why don't we use all of our brain cells
and what do we do with the brain cells that we are not using.
I'm Hannah Iaccarino and I'm a researcher
at the Picower Institute for Learning and Memory at MIT.
I'm here today to answer a question.
The question is, why don't we use all our brain cells.
Well guess what-- we actually do.
We just don't use them all at the same time.
Now there are three main reasons for that.
The first being that there are two major types of brain cells.
The first are neurons.
These cells are the ones we traditionally think
of as existing in the brain.
They communicate with each other and help
us perform all the tasks we normally
perform during the day, like talking, learning, listening.
Now, there's another type of cell in our brain
that we don't think about as often.
Those cells are called glia.
These glia are there to help the neurons do their daily tasks.
So when neurons are talking to each other
and doing their normal activities
to help us do our normal activities,
they'll sometimes create waste, and glia
will help clean up that waste.
Another example of what glia do is
that when the neurons are injured--
say you bump your head and get a concussion-- the glia will
become activated and help fix the neurons so your brain can
function properly again.
We use all of our cells but we don't use all of them
at the same time.
You wouldn't use those repair cells
unless there was something to repair.
The second example, is that we need
lots of different parts of our brain
because we do lots of different things with our brain.
To help us walk, we need our motor cortex
and it controls our feet, and our legs,
and it helps us walk in the proper pattern,
and control our muscles.
To learn and form a memory, you need a totally different brain
area called the hippocampus.
And that brain area takes in outside information
and packages it into a pretty little package
so that we can remember that memory from now until forever.
Now of course when we're walking,
we're not going to want to use all our memory cells to control
our legs and so even though we'll
use our memory cells and our motor cells,
we'll use them at different times for different activities.
The third thing is that the brain functions
a lot like a computer.
If we think about a computer having bytes
where we're going to store memory,
imagine if you used up all your bites
just by turning on your computer and saving one single file.
That would be a very inefficient computer
because you'd have to have a new computer for every document you
Now think about your brain.
If you used every cell for a single memory,
you'd need a new brain for every memory
and that is just not possible.
So in response to your question, it's actually a rumor
that we don't use all our brain cells.
We use them all-- we just don't use them all at the same time.