Welcome to Nervous System. I am a neurobiologist, so this is my favorite unit in the HumBio curriculum. The subject of this unit, the nervous system, is of great interest to students. When students are asked what part of the body they would like to learn about, the most common answer is “the brain”. This is not so surprising considering as is pointed out in this unit, that your brain is you, Your brain defines who you are, what you know, how you behave, and what you think. If it were medically possible, you could imagine transplanting any part of your body except your brain and still be you. But, if you received a brain transplant, you would be the person who donated the brain. Isn't that an interesting thought? The human brain is the most complex matter in the known universe, so it is fascinating to scientists as well as to your students. Knowledge about the brain is expanding rapidly. Almost daily there are articles in the popular press reporting new discoveries about the brain and nervous system. After completing this unit, your students will be able to read and understand any of these articles.
Neurobiology can get complex fast, but I don't think you and your students will find this unit difficult. We begin with a structural focus to give students a conceptual road map to build on. We then get students to use that road map by working through simple reflexes. Thus, they can experience directly what they are studying. We then go to the building blocks of the nervous system, neurons, and explain how these cells work to receive and communicate information.
At this point in the unit, you will have a choice. You can teach the entire unit by referring only to nerve signals or nerve impulses. Or, you can take some extra time and explain the physics and membrane biology involved in nerve impulses. This is a good opportunity to team with your physical science colleagues, but you can also do it alone. We have tried to offer very basic explanations of electricity and membrane biology necessary to explain how nerve impulses are generated and conducted down the long processes of neurons. Although you might think this information is too advanced for your class, don't be afraid to try it. Also, don't be afraid of students asking questions you cannot answer. It happens to me all of the time. Perhaps the richest teaching and learning experiences I have had have started “I don't know, but let's find out.” The most important thing students can learn from this curriculum is the habit of asking good questions and how to find the answers.
As with all HumBio units, the activities are extremely valuable components of the learning experience. They are not difficult, and they do not require sophisticated equipment. Most only require common household items. The “Thinking Cap” activity is a wonderful way to teach students to think about the brain as a three-dimensional structure. It requires only grocery store bags, crayons, and scissors, yet students who have done this activity have a better grasp on the layout of the brain than do many beginning medical students.
Please let us know about your experience with this Nervous System.
H. Craig Heller
Chair, Department of Biological Sciences, Stanford University