Weird brain myths from history

This is what a single brain cell, or neuron, really looks like. It’s pretty crazy we can take a picture of it.

Thomas Deerinck and Mark Ellisman, 2009.

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.

This is the transcript of my latest video, Weird Brain Myths from History. View the whole video here: 


This Is Your Brain On Drugs 

Designer Meaghan Li has created these colourful – and very informative – posters which show how our brain reacts on drugs.

‘Each poster is either figurative (the dissociative circles for ketamine and the sharp spikes for cocaine), visual (the psychedelic patterns for acid and DMT), or literal (the ghost-like spirit for Heroin). The one that stumped people the most was the marijuana one.

‘I tried to show melting, taking the edge off, and the subtle visual effects that it can cause.’