Volume 3, Issue 10 (October, 1999)


Welcome to the Neuroscience for Kids Newsletter.

Here is what you will find in this issue:

1. What's New on the Neuroscience for Kids Web Pages
2. The Neuroscience for Kids Page of the Month
3. Dinosaur Brains
4. Society for Neuroscience Annual Meeting
5. Book Review
6. Media Alert
7. Treasure Trove of Brain Trivia
8. How to Stop Your Subscription


Neuroscience for Kids had several new additions in September. Here are some of them:

A. September Neuroscience for Kids Newsletter was archived
B. Back to School "Brain Cards"
C. Halloween "Brain Card"
D. Autism
E. High School Sports and Brain Injury
F. Toasty Toes May Help You Fall Asleep
G. Mickey's Memory Maximized by Man

In September, 49 new figures were added and 52 pages were modified.


The Neuroscience for Kids "Page of the Month" for October includes the Charles A. Dana Foundation and Dana Alliance for Brain Initiatives web site at:

The Dana Foundation is a nonprofit organization with interests in health and education. The Dana Alliance, also a nonprofit organization, provides information about brain research and promotes the importance of learning about the brain. The Dana Alliance, with help from other organizations such as the Society for Neuroscience, organizes "Brain Awareness Week" each March.

The Dana web site has several publications for people interested in neuroscience:

* "Brainwork" - a newsletter published every two months with information about clinical and basic neuroscience research.

* "The Brain in the News" - a monthly publication with neuroscience-related stories from major newspapers.

* "Brain Connection" - a wonderful resource that lists the addresses, phone numbers, web sites and e-mail addresses of more than 275 government and private organizations concerned with neurological disorders.

* "Cerebrum" - a new Dana publication that interprets research findings and presents controversial findings in a new light.

Some of these publications are free and can be sent to you by mail.

3. Dinosaur Brains

A good dinosaur story is hard to resist. There is so much we don't know about these great reptiles. What color were they? Where did dinosaurs live? What did they eat? How did they behave?

What about dinosaur brains? How "smart" were dinosaurs? Because the brain is a soft tissue and is not preserved as a fossil, most of the information about dinosaur brains comes from skull fossils. To get an idea of what a dinosaur brain looks like, scientists can make an imprint of the inside of the skull. These imprints are called "endocasts." An endocast is made by coating the inside of the skull with latex. After the latex has dried onto the lining of the skull, it is separated from the skull and pulled out through the opening of the skull (the foramen magnum) where the spinal cord starts. When the latex bag is filled with plaster, a model of the brain is created. Sometimes sediments fill the skull. When these sediments solidify, they may create a natural endocast. By studying endocasts, researchers can estimate the size and shape of the dinosaur brain.

So just how large were dinosaur brains? Scientists have compared the sizes of dinosaur brains to those of living reptiles. One way to make these comparisons is to look at the relationship between body size and brain size of different animals. Researchers have found that brain weight is generally proportional to the two-thirds power of body weight (a logarithmic function). The mathematical function is:

E = kP^.67 (read this as, "The expected brain weight [E] is equal to a constant [k] times body weight [P] to the two-thirds power)

Using the ratio of brain weight to body weight, it is possible to estimate how large a brain "should be." If you know an animal's body weight, you can calculate its expected brain weight by using the two-thirds power rule. With animals that are not extinct, it is possible to get a real specimen and measure its actual weight. The ratio of the actual brain weight to expected brain weight is called the "encephalization quotient" or EQ. The EQ has been used as an estimate of intellectual potential.

Let's do some math:

For humans, the expected brain weight for a person weighing 150 pounds (68 kg or 68,000 g) is:

(.12)*68,000^.67 = 199.9 g

(where .12 is a constant; 68,000 g is the body weight of an "average" person; ^.67 is the two-thirds power)

However, the actual brain weight for humans is 1,400 g. Therefore, the EQ for humans is about 7:

1,400/199.9 = 7

This means that our brains are seven times larger than that of an average mammal with a similar body size.

Here are some EQs of other animals:

Dolphin = 3; Chimpanzee = 2; Elephant = 1

Let's get back to dinosaurs. A different constant (0.007) is used to calculate the EQ in reptiles. Compared to living reptile brains, most dinosaur brains appear to be about average; they had EQs ranging from 0.5 up to 5.0. So, in contrast to what many people believe, dinosaurs may not have been all that least compared to other reptiles.

Many people also think that the stegosaurus had two brains: one in the skull and one in the lower spinal cord. This is a myth. The stegosaurus had only one brain - in its head. The lower spinal cord did have an enlargement consisting of a great number of neurons in this area required to control the legs and large tail. This area also had many neurons that received sensory information from the lower limbs. Humans also have an enlargement in the lower (lumbar) spinal cord and in the upper (cervical) spinal cord to help control the arms and legs. But like the stegosaurus, we have only one brain.


It's that time of year again. Time for the annual gathering of thousands of neuroscientists from all over the world for the Society for Neuroscience Annual Meeting. This year neuroscientists will meet in Miami, Florida from October 23 to October 28.

I will be at the meeting to present a workshop to science teachers on using the Internet to teach neuroscience. I also have a poster presentation to discuss my recent experiments on nerve injury. The meeting is a chance to discuss research with other neuroscientists and to learn what is going on in other laboratories around the world.

This meeting is huge. I recently received two volumes with summaries of all of the posters and talks. Together, the two volumes contain 2,627 pages! There are 2,291 pages of posters and lectures for a total of 13,303 different presentations. All topics related to the nervous system are discussed at the meeting: memory, the senses, movement, pain, learning, neurological disease, neurotransmitters, brain blood flow, drug abuse, stress, development, language, and feeding behavior to name a few. Of course it is impossible to see all of the posters and talks, so it is necessary for each person attending the meeting to plan which presentations are most important for him or her to visit.

Many companies attend the meeting to do business with neuroscientists. Equipment manufacturers, book companies, software companies, and drug companies are just a few of the many businesses selling their products. Most companies set up booths with samples. I always try to visit these booths to see what is new and to pick up some "freebies" to bring back to my children. (I can never return home from a meeting empty-handed.)

Details of the meeting are available at the Society for Neuroscience web site:


The Promise of Sleep: A Pioneer in Sleep Medicine Explains the Vital Connection Between Health, Happiness, and a Good Night's Sleep, by William C. Dement, M.D., Ph.D. and Christopher Vaughan, New York: Delacorte Press, 447 pages, 1999 (ISBN: 0385320086)

[This book review was written by Barbara Shoup, Assistant to Dr. William Dement.]

In this book published in 1999, world-renowned sleep researcher Dr. William Dement recounts his many experiences, sometimes humorous, sometimes sobering, through four decades of work in the sleep field. He takes us through the fascinating world of sleep and cleverly shows us the inner workings of sleep and wakefulness. He reveals practical information on sleep disorders and their cures, the terrible costs of sleep deprivation to our society and how sleep affects our immune system, mood, productivity and longevity.

Dement shares with us the principles of healthy sleep, how much sleep you need and how to get the sleep you need by managing your sleep and lifestyle.

"The Promise of Sleep" is a must-read for high school students and teachers. The book provides the background of sleep medicine and plenty of basic facts about sleep. At a length of 447 pages, the book may seem intimidating, but it is written in an easy-to-read, yet entertaining manner, while still stressing the importance of healthy sleep in everyone's life.


A. "A Gene for Intelligence" in Time Magazine, September 13, 1999.

B. "Brain Power", a Fall 1999 TV program on the brain produced by the Discovery Channel. The show will be broadcast four times: October 15, 1999; November 19, 1999; December 24, 1999; January 28, 2000.

C. "How Kids Learn" in US News and World Report (September 13, 1999) reports on brain development in children.

D. "The Magnetic Sense" in Highlights for Children (October, 1999) discusses an "extra" sense in birds and other animals.

E. "Why Are You So Smart" in Discover Magazine (October, 1999) reports on the relationship between genes and intelligence.


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, in 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 The American Health Assistance Foundation,

E. In the general population, about 8% of all males and about 0.5% of all females are colorblind.


To remove yourself from this mailing list and stop your subscription to the Neuroscience for Kids Newsletter, send e-mail to Dr. Eric H. Chudler at:


Your comments and suggestions about this newsletter and the "Neuroscience for Kids" web site are always welcome. If there are any special topics that you would like to see on the web site, just let me know.


Eric H. Chudler, Ph.D.

"Neuroscience for Kids" is supported by a Science Education Partnership Award (SEPA) from the National Center of Research Resources.