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Teaching Guide
Understanding Braille
Increasing Brainpower
Nerve Cell Infomercials
Brainwaves image

For years, scientists thought that brain cells did not divide to produce new cells. However, ideas (like brain cells) do change. Today, research has shown that not only does the brain continually rewire, but regions of the brain can create brand new cells!
In “Grow Your Own Brain,” you learned how changes in surroundings and activities can boost brain growth. In the show, you saw how an enriched environment resulted in the creation of new neurons. You also observed how plain old exercise increases the brain growth of running mice. But can extra neurons really give us an edge in thinking? That's what scientists believe based on evidence from new research. Thinking power seems to be directly related to the number of connections made by brain cells. It is these connections that build the paths through which thoughts travel. The more connections, the more possible routes. The more routes, the more powerful the brain.


In this activity you will learn more about the brain and it's connections. You will then conduct an experiment to learn about stimulus and response.

This activity page will offer:

  • Background in learning brain structure and neural connections
  • A minds-on, puzzle-like experience in understanding geometric progression
  • A lab experience in conditioning of guppies



Your brain contains about 100 billion cells. Each of these cells may make up to 10,000 connections. Using these numbers, the number of possible routes along which a brain message might travel is ten to the 80th power. Ten to the 80th is a huge number. How huge? Astronomical. This number is equal to the estimated number of protons, neutrons, and electrons that may exist in the universe!


  • pencil
  • paper


Set of Dot Patterns

  1. Examine these three patterns of dots and routes. How many possible downward routes take you from the top dot to the bottom row in each pattern?"Brain" and "Neuron" Flow Chart  Diagrams
  2. Starting from the top and working your way down, how many different routes spell the word “BRAIN”?
  3. How many different routes spell the word “NEURON?
    • How does the number of possible routes increase as you add an extra step to the path?
    • What do math teachers call this doubling effect?
    • Make a guess. How many possible routes would be found in a 7-letter pattern?
  4. How good are you at creating math puzzles?
    Think about the type of challenge you'd like to create. Then, write it up and share with a partner.

Can guppies be conditioned to exhibit certain responses, like the mice you saw on Frontiers? Try this experiment to find out.


  • Five young guppies - around three weeks old*
  • Fish bowl (or plastic container)
  • Cardboard box that fits over the bowl
  • Aquarium net
  • Fish food flakes
  • Journal

*These can easily and economically be obtained from local pet stores. Often called feeder guppies, these fish make excellent subjects for behavior observations. When obtaining the guppies, ask the salesperson for any extra tips on maintaining these animals. At the end of the activity, the animals can be returned to the pet store or given to students who maintain tropical fish tanks.

Guppies in a Bowl


  1. Clean and thoroughly rinse a fish bowl using tap water. Do not use dish detergent.
  2. Fill the bowl with spring water (or water that has been appropriately treated for maintaining tropical fish).
  3. Using an aquarium net, carefully transfer five young guppies to this observation bowl.
    NOTE: Before transferring fish from one container to another, make sure that the temperatures of both tanks are the same. This is easily accomplished by leaving the bowls in the same surroundings for several hours.
  4. Feed the fish twice each day in bright light. Prior to feeding, cover the bowl for 5 minutes with a light-tight box. As soon as you remove the box, introduce into the tank one large food flake per fish. After 30 minutes remove what remains of the flake with the aquarium net.
  5. Repeat this feeding later in the day.
  6. Observe the behavior of the fish. How do the fish first behave when you remove the light tight cover? Do they surface or remain unaffected? Record your observations in a daily journal.
  7. Repeat the twice-a-day routine each day for two weeks (or until the fish become fully conditioned)
  8. After how many feedings did the fish surface immediately after removing the tank cover?


  1. What stimuli were used to condition the fish?
  2. What response did the fish develop?
  3. How long did it take for the response to develop?
  4. How might fish of different ages behave?

Suppose you wanted to uncover whether the richness of the surroundings affects the quickness at which a fish can learn. Using what you observed in the previous activity, design a controlled experiment that would uncover if an enriched environment affects learning speed.

  1. Develop your inquiry strategy in terms of a controlled experiment.
  2. What materials are needed for the control group?
  3. What materials are needed for the experimental group?
  4. Can you use the fish, which were trained in part 1 of the activity? Why or why not?
  5. How might an air bubbler affect the physical activity of the fish? What effect might this have on learning?

Discuss your experimental design with your instructor. What are the strengths and weaknesses of your method of inquiry? With your instructors approval (and needed materials), run your experiment.


  1. Suppose you were an architect in charge of designing a play space for toddlers. Using what you have learned from this Frontiers segment, sketch blueprints for the design of the playspace. For this activity, think real world. Keep the design safe, practical, and affordable. With your instructor’s approval, create a scale model of this space using paper, wood sticks, and other art materials. Write up an explanation of what you designed and why you designed it in that manner.
  2. HIGH TECH CHALLENGE - Can you construct a virtual cage that will stimulate the brain growth of rats? Using a desktop design program, construct the layout for a highly-interactive and stimulating rat cage. Your final product can be a CAD drawing, paint file, or a clip which displays a virtual walk-through of the surroundings. Write up an explanation for the logic behind your design.
  3. Do you think exercise affects your brain power? Have you ever gotten up early, exercised and then taken a school exam? If so, did morning activity affect your mood and test score? If so, how? Do you think that this type of limited exercise is more of an "attitude adjustment" technique than a method for increasing thinking power? How can you tell? Design a method of inquiry that might help you uncover any connections between pre-exam exercise and test scores.


"Understanding Braille" and "Increasing Brainpower" were contributed by Michael Dispezio, a Massachusetts-based science writer and author of "Critical Thinking Puzzles" and "Awesome Experiments in Light & Sound" (Sterling Publishing Co., NY).


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