you are here: home > links > brain trivia 1999
A. If people sleep 8 hours each day, they sleep the equivalent of 122 days per year.
B. Most people dream about 5 times during each 8-hour period of sleep. Based on this number, people have about 1,825 dreams every year.
C. An average yawn lasts about 6 seconds.
D. The distance separating two neurons at a synapse is 20-40 nanometers. (1 nanometer is equal to one-billionth of a meter.)
E. People typically blink about 15 times per minute. If you are awake for 16 hours each day, then you blink approximately 14,400 each day! (Source: Schiffman, H.R., Sensation and Perception. An Integrated Approach, New York: John Wiley and Sons, Inc., 2001)
A. Bicycle helmets reduce the risk for head injury by as much as 85% and reduce the risk for brain injury by as much as 88%. (Statistics from the Center for Disease Control.)
B. Percentage of total cerebral cortex volume (human): frontal lobe = 41%; temporal lobe = 22%; parietal lobe = 19%; occipital lobe = 18%. (Statistics from Caviness Jr., et al., Cerebral Cortex, 8:372-384, 1998.)
C. People can distinguish between 3,000 and 10,000 different smells.
D. Schizophrenia affects about 1 out of every 100 people.
E. Bees and butterflies can see ultraviolet light.
A. Each year in the United States, about 200,000 people require hospitalization for head injury and 52,000 people die due to head injuries. Another 1.74 million people have mild traumatic brain injury that requires them to visit a doctor or disables them for at least one day. (Statistics from Traumatic Brain Injury, edited by D.W. Marion, 1999, page 9 and 11.)
B. Caffeine is on the International Olympic Committee list of prohibited substances. Athletes who test positive for more than 12 micrograms of caffeine per milliliter of urine may be banned from the Olympic Games. This level of caffeine may be reached by drinking 4 or 5 cups of coffee. (Note: Caffeine was removed from the list of prohibited substances in 2004!)
C. Fevers are controlled by the part of the brain called the hypothalamus. The highest body temperature ever recorded was 115 degrees F (46.1 degrees C.) Body temperatures of 109 degrees F (42.8 degrees C) can be fatal. (Statistic from Prevention's Giant Book of Health Facts, 1991.)
D. The octopus nervous system has about 500,000,000 neurons, with two-thirds of these neurons located in the arms of the octopus. (The human brain has about 100 billion neurons.)
E. The human cerebellum weighs about 150 grams. (Total brain weight is about 1,400 grams.)
A. Epilepsy affects about 2.5 million people in the US. (Statistic from the National Institute of Neurological Disorders and Stroke.)
B. The brain of the great physicist Albert Einstein weighed 1,230 grams. This is far below the average brain weight of 1,400 grams. (Reference: Neuroscience Letters, 210:161-164, 1996.)
C. A 12 oz. can of Coca Cola has 46 mg of caffeine, a central nervous system stimulant. A cup of coffee has 60-150 mg of caffeine.
D. It is estimated that there are 60 trillion (yes, trillion) synapses in the cerebral cortex. (Reference: G.M. Shepherd, The Synaptic Organization of the Brain, 1998, p. 6.)
E. Sounds as loud as 130 dB can cause pain. Listening to sounds louder than 90 dB for an extended period of time can cause hearing damage. The loudness of normal speech is between 50 and 60 dB.
A. In 1997, 41,967 people were killed in motor vehicle traffic crashes; 16,189 fatalities were alcohol-related. This represents an average of one alcohol-related fatality every 32 minutes. (Source: National Highway Traffic Safety Administration.)
B. In the United States, one third of all adults complain about sleep problems. (Source: Consumer Health USA, by Alan M. Rees, Phoenix, Oryx Press, 1995.)
C. Each eye of a dragonfly has about 30,000 lenses.
D. A literature search ("PubMed") using the words "brain" and "1998" shows that 35,286 research papers were published in 1998.
E. The brain of an elephant weighs about 4.78 kg (10.5 lb). An adult human brain weighs about 1.4 kg (3 lb) (Source: Shoshani, J., Kupsky, W.J. and Marchant, G.H., Elephant brain. Part I: Gross morphology functions, comparative anatomy, and evolution, Brain Res. Bulletin, 70:124-157, 2006.)
A. The channel catfish has 100,000 taste buds on the outside of its body. (Statistic from J. Nolte, The Human Brain. An Introduction to Its Functional Anatomy, 4th edition, 1999.)
B. The corpus callosum, the fiber tract that connects the right and left hemispheres of the brain, contains more than 300 million axons. (Statistic from J. Nolte, The Human Brain. An Introduction to Its Functional Anatomy, 4th edition, 1999.)
C. The venom of the black widow spider is called "latrotoxin." This toxin results in the massive release of the neurotransmitter "acetylcholine" from neuromuscular junctions of its victims and may cause muscle spasms, pain, increased blood pressure, nausea and vomiting.
D. The X-ray was invented by Wilhelm Konrad Roentgen in 1895.
E. About 4 million people in the US have Alzheimer's disease. The annual cost of caring for these people is estimated to be $90 billion. (Statistic from Brain Facts, published by the Society for Neuroscience, 1997.)
A. The eardrum (tympanic membrane) is only 0.1 millimeter thick and weighs only 14 milligrams. (Statistics from W.R. Zemlin, Speech and Hearing Science, Anatomy and Physiology, 1998.)
B. The "four-eyed" fish ("Anableps") has TWO pupils in each of its eyes. Therefore it can see above and below the water simultaneously. (From E.B. Goldstein, Sensation and Perception, 1999.)
C. The human cerebral cortex has an area of about 2.5 square feet, has 25 billion neurons, is interconnected by over 100,000 kilometers of axons and receives 300 trillion synapses. (Statistics from J. Nolte, The Human Brain. An Introduction to Its Functional Anatomy, 1999.)
D. Approximately 50% of the population of the United States is nearsighted. (Statistic from Purves et al., Neuroscience, 1997.)
E. The human hypothalamus weighs about 4 grams.
A. A giraffe sleeps only two hours each day.
B. The adult human spinal cord weighs about 35 grams (0.1 lb).
C. There are about 1,200,000 nerve fibers in each human optic nerve.
D. The human eyeball is 24.5 mm (~ 1 in) long.
E. The brain of a cat weighs about 30 grams. (Remember, an adult human brain weighs about 1,400 grams or 3 lb.)
All of the statistics and facts for this month come from States of Mind: New Discoveries About How Our Brains Make Us Who We Are, edited by Roberta Conlan, New York, Dana Press, 1999, 214 pages (ISBN 0471299634)
A. As many as one in five Americans will be affected by a mental illness sometime in their lives. (p. 9)
B. There are about 3 million miles of axons in the human brain. (p. 12)
C. Of the 31,000 suicides in the United States each year, 60-80% are associated with depression or manic-depression. (p. 54)
D. The economic cost of stress and stress-related disorders in the United States is $200 billion each year. (p. 83)
E. The aplysia ("sea hare") has a nervous system with only 20,000 neurons. (p. 169)
A. Odin, a central character in Norse mythology, used two ravens named "Thought" and "Memory" to bring him news from around the world.
B. Head injuries account for 62% of bicycle-related deaths. (Statistic from Morbidity and Mortality Weekly Report, Feb. 17, 1995.)
C. After early childhood and until puberty, synapses in the human neocortex are lost at a rate of 100,000 synapses per second. (from P.T. Rakic, Annals New York Academy Sciences, Vol. 882, p. 104, 1999.)
D. Glaucoma is a leading cause of blindness in the United States. Approximately 5,400 Americans go blind from glaucoma each year. (from BrightFocus Foundation)
E. In the general population, about 8% of all males and about 0.5% of all females are colorblind.
A. The gene responsible for Huntington's disease was discovered in 1993.
B. The cerebral cortex makes up about 77% of the total volume of the human brain. (Statistic from Trends in Neuroscience, November 1995.)
C. Humans can hear sounds with frequencies between 20 and 20,000 Hz; cats can hear frequencies between 100 and 60,000 Hz; elephants can hear frequencies between 1 and 20,000 Hz.
D. Written about 1,700 B.C., the Edwin Smith surgical papyrus contains the first recorded use of the word "brain."
E. The National Institutes of Health was established in 1887.
A. The term "homo sapiens" comes from the Latin words meaning "wise man."
B. People who say they write with their right hand = 89.06%; those who write with their left hand = 10.60%; those who write with either hand = 0.34% (statistics from W. Calvin, The Throwing Madonna: Essays on the Brain, 1983).
C. In 1891, Wilhelm von Waldeyer coined the term "neuron."
D. The spinal cord runs through bones called vertebrae. A giraffe has seven vertebrae in its neck...this is the same number of neck bones as in people and most other mammals.
E. The world's largest invertebrate (animal without a backbone) is the giant squid (Architeuthis dux). The giant squid can grow up to 18 m (59 ft) long and weigh up to 900 kg (1,980 lb).
More trivia from other years:
Copyright © 1996-2013, Eric H. Chudler All Rights Reserved.