The Nervous System
“The human brain has more switches than all the computers on Earth. Researchers at Stanford developed a new imaging method that enables visualization in unprecedented detail of the myriad connections between nerve cells in the brain. “They found that the brain’s complexity is beyond anything they’d imagined, almost to the point of being beyond belief,” says Stephen Smith, a professor of molecular and cellular physiology and senior author of the paper describing the study. One synapse, by itself, is more like a microprocessor–with both memory-storage and information-processing elements–than a mere on/off switch. In fact, one synapse may contain on the order of 1,000 molecular-scale switches. A single human brain has more switches than all the computers and routers and Internet connections on Earth.
A typical, healthy brain houses some 200 billion nerve cells, which are connected to one another via hundreds of trillions of synapses. Each synapse functions like a microprocessor, and tens of thousands of them can connect a single neuron to other nerve cells. In the cerebral cortex alone, there are roughly 125 trillion synapses, which is about how many stars fill 1,500 Milky Way galaxies. These synapses are so tiny (less than a thousandth of a millimeter in diameter) that humans haven’t been able to see with great clarity what exactly they do and how, beyond knowing that their numbers vary over time. That is until now.
Researchers at the Stanford University School of Medicine have spent the past few years engineering a new imaging model, which they call array tomography, in conjunction with novel computational software, to stitch together image slices into a three-dimensional image that can be rotated, penetrated and navigated.”
Content: The Nervous System
Do we have electricity inside of us? Yes, we do. Ripples of electricity take messages to our brain. Electricity travels to the brain along cells called neurons and the brain gets the message and tells us what to do.
Where is our brain? Our brain is inside our head and is protected by the bones of our skull. The long chord that comes from our brain is our spinal chord and it is inside the vertebrae of our back. These bones protect the spinal chord. Nerve cells carry electrical signals to and from the spinal chord. All five of our senses are connected to our brain. The brain tells us to move or if we are touching something. The fastest brain message travels 360 mph!
The brain, spinal chord and nerves (31 pair of spinal nerves) make up our nervous system and control the actions and sensations of the whole body. The largest cells in our body are nerve cells. In the brain they are very small, but they can be as long as 4 feet in our legs. Point out the parts of the nervous system on the chart. The spinal nerves have 2 jobs; taking messages to the brain and reflexes.
Draw a picture of a neuron. There are 3 kinds of neurons: motor, sensory, and connector. We have 100 billion neurons in our body. The brain controls the whole body and tries to keep it stable (homeostasis).
What gives the brain energy? OXYGEN from the air we breathe gives the brain energy. If the brain goes for 5 minutes without oxygen then it begins to die. If we learn something new, the brain grows and makes new connections!
When we are asleep the brain keeps our heart beating and our lungs breathing. We have a built in sleep-wake clock. Lack of sleep can hurt us because this is when the brain stores up chemicals it will need for the next day. In our lifetime we will sleep almost 30 years! Our brain uses a lot of energy (20%) and consumes a lot of oxygen (1/4th of the body’s oxygen)
People who study the brain are called Neurologists. Neurologists believe that the brain is surrounded by liquid crystals. Show the liquid crystals and how they respond to the heat of your hand.
Not only does the brain control the whole body, but also your emotions, pain, thoughts, and memory. The right side of the brain controls the left side of the body and the left side of the brain controls the right side of the body.
Examine the model of the brain and point out the two cerebral hemispheres and the brain stem that attaches to the spinal chord. The brain works using chemicals and electricity and is sensitive to the food we eat. Some things can hurt our brain like poisons from certain plants or animal bites, pollution in the air and exposure to certain chemicals and metals can cause nutritional imbalances, allergies, brain fog, and chronic fatigue.
We are what we eat! It starts with the soil that determines the nutrients in the plants we eat. Without copper, plant leaves turn yellow. If we get too little copper, we can develop brain fog, thyroid and hormone problems. If we don’t get enough calcium and magnesium, nerves fire improperly, awareness is lessened, and we experience mental fatigue and numbness. It is important where our food comes from, how it is grown, and how clean the environment is.
Use your noodle and make new connections! What animal do you think has the biggest brain? The sperm whale has the biggest brain. (201 lbs.) Our brain weighs only about 3 lbs. A worm has a brain and spinal chord and even a slug is able to learn things!
Activities: Children can make the connection with their finger and light up the energy ball. Examine the chart of the nervous system and realize that nerves reach to all parts of the body and are connected to the brain by the spinal chord. Examine the model of the brain and see how it fits into the skull. Observe the change in the liquid crystals from the heat of their hand. Give them some brain teasers.
Materials: Electric ping pong ball, Skull model, Chart of the nervous system, model of the brain, drawing board and markers, liquid crystals
