The left brain vs. right brain myth - Elizabeth Waters

Summary

The video script dispels the myth of the brain being divided into a logical left and creative right hemisphere. It explains that while the brain does have distinct left and right sides controlling different body functions, such as movement and sight, there's no scientific evidence supporting the idea that one side governs logic and the other creativity. Historical misconceptions arose from 19th-century neurologists' findings on language localization in the left hemisphere. Modern research shows that both hemispheres contribute to a range of cognitive functions, and individual differences in logic and creativity are not determined by brain lateralization.

Takeaways

• 🧠 The human brain is visibly split into left and right sides, but the idea that the left controls logic and the right creativity is a myth.
• 🤔 The brain's left and right sides do control different body functions, such as movement and sight, but this doesn't extend to logic and creativity.
• 👀 The visual system is complex, with each eye having a left and right visual field, and these fields are sent to opposite sides of the brain.
• 🦎 The theory of quicker reflexes due to the left-right structure of the brain might have originated with the development of complex nervous systems in animals.
• 🏥 The misconception of a logical left hemisphere and an emotional right hemisphere began in the mid-1800s with neurologists Broca and Wernicke's findings on language and brain damage.
• 📚 Author Robert Louis Stevenson popularized the idea of a logical left hemisphere and an emotional right hemisphere through his characters Dr. Jekyll and Mr. Hyde.
• 🧬 Patients missing a hemisphere or with separated hemispheres showed a complete range of behaviors, indicating that both logic and creativity are not confined to one side of the brain.
• 🧐 Later research showed that language is more localized to the left side of the brain, and attention to the right, but this doesn't suggest a person has a dominant side for these functions.
• 🤹‍♂️ Creativity and logic are not at odds; they often require each other, and both are the result of the whole brain functioning as one.
• 🧬 There is no scientific evidence to support the idea of individuals having dominant brain hemispheres or a split between logic and creativity based on brain sides.

Q & A

What is the myth about the brain's left and right sides?

The myth is that the left side of the brain controls logic, while the right side controls creativity. This idea is unsupported by scientific evidence.

How is the brain's structure divided?

The brain is visibly split into a left and right side, with the outer layer, or the cortex, being the most apparent. Internal regions like the striatum, hypothalamus, thalamus, and brain stem also have left and right sides.

What functions do the left and right sides of the brain control?

The left and right sides of the brain control different body functions such as movement and sight. The right side controls the motion of the left arm and leg, and the visual system processes visual fields from each eye to the corresponding side of the brain.

What is one theory as to why the brain has a left-right structure for vision and movement control?

One theory is that this structure began soon after animals developed more complex nervous systems, providing a survival advantage of quicker reflexes, such as escaping to the right when a predator is seen on the left.

When did the misconception about the brain's left-right split begin?

The misconception began in the mid-1800s when neurologists Broca and Wernicke examined patients with communication problems due to brain injuries, leading to the suggestion that language is controlled by the left side of the brain.

How did the idea of a logical left hemisphere and an emotional right hemisphere become popular?

The idea became popular after author Robert Louis Stevenson introduced it through his characters Dr. Jekyll and Mr. Hyde, representing a logical left hemisphere and an emotional right hemisphere.

What did doctors and scientists find when examining patients who were missing a hemisphere or had their hemispheres separated?

These patients showed a complete range of behaviors, both logical and creative, indicating that the brain functions as a whole rather than being strictly divided into logical and creative sides.

How does the brain's activity differ for language and attention?

Language is more localized to the left side of the brain, while attention is more localized to the right side. However, this does not mean one side is dominant for all individuals.

Is there evidence to suggest individuals have dominant sides of the brain?

No, there isn't any evidence to suggest that individuals have dominant sides of the brain, nor is there evidence to support the idea of a left-right split between logic and creativity.

How are logic and creativity related in the brain?

Logic and creativity are not at odds with each other. Solving complex math problems requires creative thinking, and many works of art have intricate logical frameworks, indicating that both logic and creativity are often the result of the whole brain functioning as one.