This is what a single brain cell, or neuron, really looks like.
It’s pretty crazy we can take a picture of it.
But… for a long time we couldn’t see and didn’t quite understand that tangle of neurons
inside your head.
And some people thought we didn’t need a brain at all.
Back in Ancient Egypt, people believed the brain was just stuffing to keep the skull
from caving in.
During mummification, brains were often removed and discarded while the heart was taken with
you to the afterlife.
Ancient Egyptians believed the heart was the seat of consciousness – an idea called the
cardiocentric hypothesis.
In Ancient Greece, Alk-me-en dissected an eye and discovered the optic nerve.
He thought there were connections from our sensory organs to the brain.
So Alk-me-en proposed the cephalocentric hypothesis, that the brain was the seat of consciousness.
He believed that animal spirits ran through the body, just like we know neural signals
do today.
Others, like Pythagoras, Plato and Hippocrates were also on team brain.
But some, like Aristotle marched to the beat of a different drum, and continued to favour
team heart.
Aristotle believed the brain and lungs were cooling devices for the heart.
Skip forward almost one thousand years and French Philosopher Rene Descartes thought
our nerves contained fluids, where animal spirits would flow through our nerves to our
muscles to cause movement.
This theory, that muscle movement was caused from inflation by air or fluid, was known
as the Balloonist theory, but like those before, it soon deflated.
Then in the 1820s, the theories of Franz Joseph Gall shaped Phrenology.
People thought the mind was composed of distinct faculties – think self-esteem, benevolence
or agreeableness – that had a separate area in the brain.
And since the skull takes it’s shape from the brain, it was pretty widely accepted that
the surface of the skull could be read as an index of your psychological aptitudes and
tendencies.
Phrenology was practiced until the 1840s, and the British Phenological Society was disbanded
as late as 1967.
As Karl Popper said, “Science must begin with myths, and with the criticism of myths.”
If we didn’t once believe that we have animal spirits flowing through our veins or that
your brain was just stuffing, we may not have developed the knowledge we now have about
the brain.
Or what we'll learn about your brain in the future.