Marisa A. Ferrarese
The nervous system is an intricate system that controls the body, including thoughts, emotions, memories, actions, and sensations. The nervous system can be simplified by dividing it into its two major divisions: the central nervous system and the peripheral nervous system. The central nervous system consists of the brain and spinal cord, while the peripheral nervous system includes the body's nerves. It is important to note that the peripheral nervous system has the ability to heal itself, while the central nervous system does not.
Student Art Connection
As page one of the scrapbook, students will create a replica of the human nervous system, highlighting the three main parts. Students can either create a small scale version for their scrapbook or a life size version by tracing a classmate on chart paper then photograph it for the scrapbook. Either way students can draw (or trace) an outline of the body and add the main components of the nervous system using a variety of materials. For example, students could use stretched out cotton for the brain, pipe cleaners or popsicle sticks for the spinal cord, and yarn for the nerves. Students will view a scientific diagram of the five senses and compare it to the sculpture, Reality processor, by Brain Carroll. This will allow students to discuss why they believe the artist made particular choices and assess the piece.
The Brain
While the brain is by far the most complex sections of the nervous system, scientists know more about the brain today then ever. With this in mind, as an educator it is important to provide only age appropriate information to students. At the fifth grade level student can understand and retain basic brain structure and function.
The human brain is the control center of the central nervous system. The brain controls reason, intelligence, emotions, memory, cognition, sensory systems, heart rate, blood pressure, and more.
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There are three main parts of the human brain. First, the cerebrum is the largest and the most visible region of the brain. Its two hemispheres control our body's language and communication, movement, olfaction, memory, and emotions. The second part of the brain, the cerebellum, is also in two distinct hemispheres and is located below the cerebrum, in the back of the brain, above the brain stem. The cerebellum, which in Latin means "little brain", coordinates voluntary motor movement, balance, equilibrium, and muscle tone. The brain stem, the third part of the brain, is the major connection among the cerebrum and cerebellum and the spinal cord. It plays a vital role in attention, respiration, regulation of heart rhythms, and sound localization.6,
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Students will view a series of work by Georgia O'Keefe and then view and discuss "Georgia O'Keefe's Mind in Bloom" by Alexandra Person. Students will have the opportunity to analyze and assess the art work to determine why they believe that it won first place in the Brain Art Competition 2004.
Art Connection
"Reality Processor", Brian Carroll, Sculpture
http://www.mnartists.org/work.do?rid=99761
"Georgia O'Keefe's Mind in Bloom", Alexandra Person, painting, (2004)
Brain Art Competition 2004 - First Place
http://www.sfn.org/baw/photos.cfm
"Windows of the Mind", Eugenia Algaze Garcia, pencil, (1986)
http://www.mindful-art.com/logo%20brain%20-%20web.JPG
Scientific Imaging
Students can participate in an interactive 3D tour of the brain to better understand its structure and function.
http://www.pbs.org/wnet/brain
Students Art Connection
Two projects or a combination of the two projects can be created to represent the brain. For one project students can fold a piece of paper into four even sections. In each section students can draw a pictorial representation of the brain each from a different view. For example, the first square can display a front (frontal) view of the brain, the second square can contain a (side) lateral view, the third a back (posterior) view, and the fourth a midline (sagittal) view. Or students could create one view of the brain to fill the entire piece of paper. Then create a small picture of an eye, ear, nose, mouth, and hand to be cut out and displayed on the part of the brain that controls the specific sense. The brain should be colored, labeled, and functions described.
Medical Imaging
While learning about the complex brain students can be introduced to the various forms of medical imaging that are available, including a x-rays, ultrasound, CAT Scan, MRI and PET Scan. While all are not routinely used to study the brain, their limitations can be incorporated into the discussion. Corresponding internet sites are listed at the conclusion of this section which are recommended viewing while teaching about medical imaging. The students participating in this unit will view these images as part of a power point presentation. My goal is not for students to memorize the components of each system, but rather ultimately understand the technological possibilities and continuous advancements.
Most students are familiar with an x-ray. Each student has generally had a bone or even their teeth x-rayed at one point in their life. Educators can use this information to build on students' prior knowledge to determine whether or not a brain could be seen when x-raying the head.
X-rays are a form of electromagnetic radiation discovered by William Conrad Roentgen. Prior to his discovery in 1895, doctors had no way to determine what was going on with the body, other than cutting it open. Luckily, Roentgen happened upon the x-ray, which could be used to view the internal structure of the human body. In their most simplistic form, x-rays work by photon energy being released and absorbed by matter. X-rays travel through the person's body and unabsorbed energy is displayed on a film. Air, absorbs no photons or energy so it appears black on the film, while bone (calcium) absorbs the most energy appearing white on the film. The denser the material, the more energy that will be absorbed. Fat will appear as a dark gray and muscles, organs, or blood (water) will appear gray.
"Cranial ultrasound uses reflected sound waves to produce pictures of the brain and the inner fluid chambers…"
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Ultrasounds are most commonly used during pregnancy to determine the health of an infant. However, cranial ultrasounds can also be used on newborns because ultrasound cannot pass through the bone. At early ages the skull is not yet fused together allowing doctors to examine infants up to the age of 18 months for issues due to development or disease of the brain. The ultrasound probe is placed over the "soft spots" on the infant's skull. On adults, ultrasound can be used during brain surgery following removal of part of the skull to determine brain mass or check for bleeding.
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A computerized axial tomography scan (CAT Scan or CT) uses x-ray technology to form a three dimensional computer image of the internal body, while allowing doctors to view the body or brain in sections or slices. Instead of the one angle view that an x-ray provides, the x-ray beams moves all around the person allowing the computer to organize the information from hundreds of different angles.
Magnetic resonance imaging (MRI) has progressed greatly from their conception in 1977. Imaging that used to take hours, now only takes minutes. Using magnets and radio wave technology an MRI is able to produce a two or three dimensional image. Unlike the CAT scan which only can be viewed on one plane, the MRI can be viewed on three different planes. For example CAT scans can only interpret images cut axially, imagine a loaf of bread sliced. However, an MRI can also display images cut on a "…sagittal plane (slicing the bread side-to-side lengthwise) and coronally (think of the layers of a layer cake) or any degree in between, without the patient ever moving."
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Finally, positron emission tomography (PET) scan allows doctors to view function of the body, rather than the structure. Patients are injected with a low dose radioactive compound that is isolated to the area of the body being studied. The PET scan will produce a two or three dimensional image of the area of study. "PET scans of the brain are used to evaluate patients who have memory disorders of an undetermined cause, suspected or proven brain tumors or seizure disorders that are not responsive to medical therapy and are therefore candidates for surgery."
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Medical Imaging of the Brain
X-Ray - http://www.faqs.org/health/images/uchr_02_img0179.jpg
Ultrasound - http://www.ob-ultrasound.net/images/cscan2.jpg
CAT Scan - http://www.parhammedical.org/Parham/Illness/Brain%20Pressure.htm
MRI - http://www.lpg.man.ac.uk/web_page/photomedicine/MRI_image.htm
PET Scan - http://faculty.washington.edu/chudler/image.html
Student Art Connection
Students are going to make a hand booklet to add to their scrapbook. First, students will trace their hand on white paper, observe their hand, and color what they observe, including skin color, pores, hair, etc. Next students will trace the same hand on black construction paper and use a piece of white chalk to predict what their hand would look like in an x ray. Finally, students would trace their hand on another piece of black construction paper and draw a replica of what a hand x ray actually looks like. All three hands should be cut out, layered, stapled together, and added to the book. Students could add a written component comparing the similarities and differences between the prediction and actual depiction.
The Spinal Cord
The spinal cord begins in the brain and ends at level vertebral L1, that is, it ends two-thirds the way down the spinal column. There are 31 pairs of spinal nerves extending off of the spinal cord containing thousands of sensory and motor nerves. These nerves help the body transport information to and from the brain and to other parts of the body. The spinal cord basically controls almost every muscle from the neck down, transmitting sensory information to the brain. Its importance to understanding the world around us is imperative. As a result, the spinal cord is protected by the strong bones of the spinal column called vertebrae.
The Nerves
The peripheral nervous system is made up of hundreds of nerves. Each nerve is like a cable wire filled with smaller nerve cells or neurons. While most nerves connect through the spinal cord,
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cranial nerves connect directly to the human brain. Information from your five senses is received through one of the many sensory nerves and the brain will interpret the message and react via the motor nerves. The sciatic nerve is the longest nerve in the body, running from the spinal cord down the leg to the big toe. Students will participate in activity to better understand how the nervous system works. With a class in a large circle each person will put their right hand on the persons shoulder standing to their right. One person starts by squeezing the person's shoulder next to them. I will clock the time it takes to make it around the full circle and record the results on the board. Next, students sit and squeeze the person's foot to the right of them. Again, I record the time it takes for the message to pass all the way around the circle. It should take longer when the information has to travel from the foot to the brain than the shoulder to the brain, because the information has less of a length to travel.