You have 3 brains. This is how to use them | Robert Sapolsky

SecondBrainJune 8, 2023, 1:07 p.m.

The article is a theoretical piece.

Robert Sapolsky explains the concept of the "Triune brain," a way of thinking about the three layers of brain function: the reptilian brain, the limbic system, and the cortex. He describes how these layers interact with each other and how conscious thinking can regulate ancient, unconscious parts of the brain for better health.

Main topics: brain function, the "Triune brain" concept, interaction between brain layers, conscious regulation of the brain

Secondary topics: autonomic nervous system, biofeedback, emotional responses, cortical judgment

Understanding the Triune Brain

Despite the complexity of the brain, there is a simple way to understand brain function and behavior. This involves understanding the 'Triune Brain,' which was conceptualized by Paul McClean. While the brain does not come in three distinct layers, it is possible to consider it this way.

The oldest and most ancient layer is the 'reptilian brain,' which handles regulatory functions such as body temperature and blood glucose levels. The next layer is the 'limbic system,' responsible for emotions and arousal. The top-most layer is the cortex, responsible for abstract cognitive processes.

Interaction Between Layers

Each layer has different functions but they are connected and interact. For instance, the limbic system can activate the reptilian brain, as seen when an emotional response causes a stress response. Likewise, the cortex can influence the limbic system, which is responsible for emotional responses to abstract cognitive processes. This means that there is a three-to-two-to-one scenario or a one-to-two-to-three scenario.

Conscious Control

While interactions between the different layers are often unconscious, it is possible to consciously regulate and control them. Biofeedback is one such technique that allows individuals to control their reptilian brain in response to conscious thoughts. By thinking about positive or happy memories, individuals can lower their heart rate and blood pressure. This technique allows individuals to consciously regulate and control more ancient parts of the brain.

Conclusion

Understanding the Triune Brain and its interactions can help individuals better understand brain function and behavior. With conscious control, individuals can regulate their emotions and bodily functions, leading to better health.

Triune Brain Quiz

Question 1: What is the 'Triune Brain'?

a. The three different functions of the brain.
b. The way information flows through the brain.
c. The idea that the brain can be separated into three functional layers.
d. The way the brain processes emotions and experiences.

correct answer: c. The idea that the brain can be separated into three functional layers.

Question 2: Which layer of the brain is responsible for regulating bodily functions?

a. Layer one.
b. Layer two.
c. Layer three.
d. None of the above.

correct answer: a. Layer one.

Question 3: Which part of the brain is responsible for emotional responses?

a. Layer one.
b. Layer two.
c. Layer three.
d. All of the above.

correct answer: b. Layer two.

Question 4: Which layer of the brain is the most recently evolved?

a. Layer one.
b. Layer two.
c. Layer three.
d. They all evolved at the same time.

correct answer: c. Layer three.

Question 5: Which layer of the brain can influence the other layers in the brain?

a. Layer one.
b. Layer two.
c. Layer three.
d. All of the above.

correct answer: d. All of the above.

Brain Layers Quiz

Question 1: What is the function of layer one of the Triune Brain?

a. Emotional response.
b. Cognitive processing.
c. Regulation of bodily functions.
d. All of the above.

correct answer: c. Regulation of bodily functions.

Question 2: Which layer of the brain is responsible for fear and anxiety?

a. Layer one.
b. Layer two.
c. Layer three.
d. None of the above.

correct answer: b. Layer two.

Question 3: Which layer of the brain is the most recently evolved?

a. Layer one.
b. Layer two.
c. Layer three.
d. They all evolved at the same time.

correct answer: c. Layer three.

Question 4: Which layer of the brain can influence the other layers in the brain?

a. Layer one.
b. Layer two.
c. Layer three.
d. All of the above.

correct answer: d. All of the above.

Question 5: How is the cortex involved in emotional responses?

a. It is responsible for emotional reactions.
b. It can influence layer two, which is responsible for emotional responses.
c. It has no role in emotional responses.
d. None of the above.

correct answer: b. It can influence layer two, which is responsible for emotional responses.

Interaction between Brain Layers Quiz

Question 1: What is the inverse of layer one influencing layer three?

a. Layer three influencing layer two.
b. Layer two influencing layer one.
c. Layer one influencing layer three, but in the opposite direction.
d. None of the above.

correct answer: c. Layer one influencing layer three, but in the opposite direction.

Question 2: How does layer two influence layer three?

a. By regulating bodily functions.
b. By controlling abstract cognitive processes.
c. By evoking emotional responses.
d. None of the above.

correct answer: c. By evoking emotional responses.

Question 3: How can we consciously regulate the reptilian brain?

a. By thinking about upsetting memories.
b. By thinking about happy memories.
c. By taking anti-hypertensive drugs.
d. None of the above.

correct answer: b. By thinking about happy memories.

Question 4: Which layer of the brain can be affected by biofeedback?

a. Layer one.
b. Layer two.
c. Layer three.
d. All of the above.

correct answer: d. All of the above.

Question 5: Why do hunger and pain affect our moral judgments?

a. Because they make us feel angry.
b. Because they change the way the cortex assesses pro-sociality and altruism.
c. Because they make us less charitable.
d. None of the above.

correct answer: b. Because they change the way the cortex assesses pro-sociality and altruism.

Neuroscience