Brain Facts (Psychology)
The human brain is about 60% fat, weighs approximately 3 pounds, and is the fattiest organ in the body. It generates about 12-25 watts of electricity while awake and processes information at speeds of up to 350 miles per hour.
The brain is the control center for thought, memory, emotion, and all bodily functions, but it is not fully formed until around age 25.
Composition of Brain
Composition
The brain is about 60% fat, with the remaining 40% a mix of water, protein, carbohydrates, and salts. It is not a muscle.
Control center:
It regulates voluntary and involuntary movements, processing sensory information, and is the center for learning, memory, emotion, and thought.
Energy:
The brain uses glucose from the body to produce enough electricity to power a small light bulb (about 12-25 watts) while a person is awake.
Speed:
Information travels from the body to the brain at speeds of 150-260 miles per hour, and brain signals can travel up to 350 miles per hour.
Development of Brain
Full development:
The human brain is not fully formed until around age 25.
Nervous system:
The brain is the main part of the central nervous system, along with the spinal cord.
Cranial nerves:
The brain has 12 cranial nerves that carry messages between the brain, organs, and muscles.
How to improve Brain Health
Healthy diet:
Eating healthy foods provides the brain with the necessary glucose to function.
Exercise:
Physical activity is crucial for brain health.
Mental stimulation:
Challenging the mind is important for maintaining cognitive function.
Safety:
Always wear a helmet when riding a bike or scooter to protect the brain from injury.
Reading aloud:
Reading aloud can help promote brain development.
Weight & Size
The average adult human brain weighs about 1.4 kg (3 pounds) — roughly 2% of body weight, but consumes ~20% of the body’s energy.
Number of Neurons
~86 billion neurons in the human brain (not 100 billion — that was an old estimate).
The cerebral cortex alone has about 16–23 billion.
No Pain Receptors
The brain itself has no pain receptors (nociceptors).
That’s why brain surgeons can operate on awake patients (local anesthesia only for the scalp and skull).
Blood Flow
Receives ~15–20% of cardiac output (750 ml/min).
If blood flow stops for ~10 seconds you lose consciousness; after 3–4 minutes without oxygen, permanent damage begins.
80% Water
The brain is ~73–80% water.
Even mild dehydration (1–2%) impairs attention and cognition.
10% Myth
Humans use far more than 10% of their brain.
Even simple tasks activate many regions, and virtually all of the brain is active over a 24-hour period.
New Neurons in Adulthood
Contrary to old dogma, humans do generate new neurons (neurogenesis) in the hippocampus throughout life, especially with exercise and learning.
Extra strange facts about Brain
Your brain can generate up to 50,000–70,000 thoughts per day.
The smell of rain or your own home can trigger powerful memories because the olfactory bulb has direct connections to the amygdala and hippocampus.
When you recall a memory, you’re not replaying a “video tape” — you’re reconstructing it, which is why memories can change over time.