Brain Structure

The human brain is the center of the human nervous system. It has the same general structure as the brains of other mammals, but is larger than expected on the basis of body size among other primates.[ Estimates for the number of neurons (nerve cells) in the human brain range from 80 to 120 billion.Most of the expansion comes from the cerebral cortex, especially the frontal lobes, which are associated with executive functions such as self-control, planning, reasoning, and abstract thought. The portion of the cerebral cortex devoted to vision is also greatly enlarged in human beings, and several cortical areas play specific roles in language, a skill that is unique to humans.

Despite being protected by the thick bones of the skull, suspended in cerebrospinal fluid, and isolated from the bloodstream by the blood–brain barrier, the human brain is susceptible to many types of damage and disease. The most common forms of physical damage are closed head injuries such as a blow to the head, a stroke, or poisoning by a variety of chemicals that can act as neurotoxins. Infection of the brain, though serious, is rare due to the biological barriers which protect it. The human brain is also susceptible to degenerative disorders, such as Parkinson's disease, multiple sclerosis, and Alzheimer's disease. A number of psychiatric conditions, such as schizophrenia and depression, are thought to be associated with brain dysfunctions, although the nature of such brain anomalies is not well understood.

The human brain has amazed and baffled people throughout the ages. Some scientists and doctors have devoted their entire lives to learning how the brain works. It is no wonder that people enjoy learning facts about this incredible organ in the human body. Below, you will find some interesting facts about the brain including how it works, how it develops, what it controls, how it affects sleep, dreams, and memory and more.

Physical Attributes

These facts will teach you interesting bits of information about the physical make-up of the human brain.

1. Weight.

The weight of the human brain is about 3 lbs.

2. Cerebrum.

The cerebrum is the largest part of the brain and makes up 85% of the brain’s weight.

3. Skin.

Your skin weighs twice as much as your brain.

4. Gray matter.

The brain’s gray matter is made up of neurons, which gather and transmit signals.

5. White matter.

The white matter is made up of dendrites and axons, which create the network by which neurons send their signals.

6. Gray and white.

Your brain is 60% white matter and 40% gray matter.

7. Water.

The brain is made up of about 75% water.

8. Neurons.

Your brain consists of about 100 billion neurons.

9. Synapses.

There are anywhere from 1,000 to 10,000 synapses for each neuron.

10. No pain.

There are no pain receptors in the brain, so the brain can feel no pain.

11. Largest brain.

While an elephant’s brain is physically larger than a human brain, the human brain is 2% of total body weight (compared to 0.15% of an elephant’s brain), meaning humans have the largest brain to body size.

12. Blood vessels.

There are 100,000 miles of blood vessels in the brain.

13. Fat.

The human brain is the fattest organ in the body and may consists of at least 60% fat.

The Developing Brain

Starting from within the womb, fetal brain development begins the amazing journey that leads to a well-developed brain at birth that continues to grow for 18 more years.

14. Neurons.

Neurons develop at the rate of 250,000 neurons per minute during early pregnancy.

15. Size at birth.

At birth, your brain was almost the same size as an adult brain and contained most of the brain cells for your whole life.

16. Newborn’s growth.

A newborn baby’s brain grows about three times its size in the first year.

17. Stopped growing.

Your brain stopped growing at age 18.

18. Cerebral cortex.

The cerebral cortex grows thicker as you learn to use it.

19. Stimulation.

A stimulating environment for a child can make the difference between a 25% greater ability to learn or 25% less in an environment with little stimulation.

20. New neurons.

Humans continue to make new neurons throughout life in response to mental activity.

21. Read aloud.

Reading aloud and talking often to a young child promotes brain development.

22. Emotions.

The capacity for such emotions as joy, happiness, fear, and shyness are already developed at birth. The specific type of nurturing a child receives shapes how these emotions are developed.

23. First sense.

The first sense to develop while in utero is the sense of touch. The lips and cheeks can experience touch at about 8 weeks and the rest of the body around 12 weeks.

24. Bilingual brains.

Children who learn two languages before the age of five alters the brain structure and adults have a much denser gray matter.

25. Child abuse and the brain.

Studies have shown that child abuse can inhibit development of the brain and can permanently affect brain development.

Brain Function

From the invisible workings of the brain to more visible responses such as yawns or intelligence, find out how the brain functions with these facts.

26. Oxygen.

Your brain uses 20% of the total oxygen in your body.

27. Blood.

As with oxygen, your brain uses 20% of the blood circulating in your body.

28. Unconsciousness.

If your brain loses blood for 8 to 10 seconds, you will lose consciousness.

29. Speed.

Information can be processed as slowly as 0.5 meters/sec or as fast as 120 meters/sec (about 268 miles/hr).

30. Wattage.

While awake, your brain generates between 10 and 23 watts of power–or enough energy to power a light bulb.

31. Yawns.

It is thought that a yawn works to send more oxygen to the brain, therefore working to cool it down and wake it up.

32. Neocortex.

The neocortex makes up about 76% of the human brain and is responsible for language and consciousness. The human neocortex is much larger than in animals.

33. 10%.

The old adage of humans only using 10% of their brain is not true. Every part of the brain has a known function.

34. Brain death.

The brain can live for 4 to 6 minutes without oxygen, and then it begins to die. No oxygen for 5 to 10 minutes will result in permanent brain damage.

35. Highest temperature.

The next time you get a fever, keep in mind that the highest human body temperature ever recorded was 115.7 degrees–and the man survived.

36. Stress.

Excessive stress has shown to "alter brain cells, brain structure and brain function."

37. Love hormones and autism.

Oxytocin, one of the hormones responsible for triggering feelings of love in the brain, has shown some benefits to helping control repetitive behaviors in those with autism.

38. Food and intelligence.

A study of one million students in New York showed that students who ate lunches that did not include artificial flavors, preservatives, and dyes did 14% better on IQ tests than students who ate lunches with these additives.

39. Seafood.

In the March 2003 edition of Discover magazine, a report describes how people in a 7-year study who ate seafood at least one time every week had a 30% lower occurrence of dementia.


Learn how scent, jet lag, and estrogen affect memory, plus plenty of other information, with these facts.

40. Jet lag.

Frequent jet lag can impair your memory, probably due to the stress hormones released.

41. New connections.

Every time you recall a memory or have a new thought, you are creating a new connection in your brain.

42. Create associations.

Memory is formed by associations, so if you want help remembering things, create associations for yourself.

43. Scent and memory.

Memories triggered by scent have a stronger emotional connection, therefore appear more intense than other memory triggers.

44. Anomia.

Anomia is the technical word for tip-of-the-tongue syndrome when you can almost remember a word, but it just won’t quite come to you.

45. Sleep.

While you sleep at night may be the best time for your brain to consolidate all your memories from the day.

46. No sleep.

It goes to follow lack of sleep may actually hurt your ability to create new memories.

47. World Champion.

A world champion memorizer, Ben Pridmore memorized 96 historical events in 5 minutes and memorized a single, shuffled deck of cards in 26.28 seconds.

48. Estrogen and memory.

Estrogen (found in both men and women) has been shown to promote better memory functions.

49. Insulin.

Insulin works to regulate blood-sugar in the body, but recently, scientists have discovered that its presence in the brain also helps promote memory

. Famous Brains

People have always been fascinated with the brains of famous people. Find out what experts know about these famous brains.

50. Albert Einstein.

Einstein’s brain was similar in size to other humans except in the region that is responsible for math and spatial perception. In that region, his brain was 35% wider than average.

51. London taxi drivers.

Famous for knowing all the London streets by heart, these drivers have a larger than normal hippocampus, especially the drivers who have been on the job longest. The study suggests that as people memorize more and more information, this part of their brain continues to grow.

52. VI Lenin.

After his death, Lenin’s brain was studied and found to have an abnormally large and numerous neurons in a particular region that may explain his "strikingly acute and penetrating mental processes" for which he was famous.

53. Oldest brain.

A brain thought to be 2000 years old was unearthed just recently at the University of York in northern England.