CEREBRUM – Responsible for reasoning, thought, memory, judgment, speech,
sensation, sight, smell, hearing, and voluntary movement. Lies above the cerebellum.
Has left and right hemispheres and divided into 4 lobes.
Frontal Lobe – controls voluntary motor movements, expression, and moral
behavior.
1. Start building the brain with clay.
2. Each lobe of the cerebrum will be built with a color.
3. The frontal lobe will be built with “terra cotta (red/orange)” because it
is the same color as the muscles . . . Which is controlled by the frontal
lobe. (Let the students know why this color is being used!)
4. Frontal lobe – start with a ball
of terra cotta clay about the size of a
peanut M&M, roll the ball into a tube
and then into a strand about the
diameter of linguini – thicker than
the strands made for the tendons.
5. Hold the strand above the
palm of the other hand. Let the
strand fall into the palm – form a
messy clump. Using the other hand,
gently roll the clump into a ball. (DO NOT smooth out the gyrus . . . or this
brain will lose it intelligence.)
6. Place the lobe on your skeleton.
Parietal Lobe – controls and interprets the senses and taste.
1. Use blue clay for this lobe, because “bright blue” is a sensitive color and
the Parietal lobe is all sensory.
2. Place behind the Frontal lobe.
Occipital Lobe – controls vision and various forms of expression.
1. Use “yellow” clay for this lobe.
2. Form a ball about the size of a regular M&M and place it into the spot where
the occipital lobe would go.
3. Leave space at the bottom of the skull for the cerebellum.
Temporal Lobe – controls memory, equilibrium, emotion, and hearing.
1. Using “gray” clay about the size of a peanut M&M, shape and fit the temporal
lobe.
2. This lobe will be oval shaped and placed under the parietal lobe and halfway
under the frontal lobe.
3. Remind students that the sphenoid bone forms a shelf for the front of the
frontal lobe. You want to see an invisible shelf when the temporal lobe is
placed into the skull.
4. CEREBRUM is FINISHED!
5. The colored lobes of the brain represent the Cerebrum of the brain or
the Somatic brain (voluntary).
CEREBELLUM – Responsible for muscle coordination, balance, posture, and muscle
tone.
1. Little part of the brain with a big name.
2. Use “ivory/white” clay to represent the involuntary parts of the brain,
beginning with the cerebellum.
3. Form a ball of clay about the size of a regular M&M, and place it under the
occipital lobe and part of the temporal lobe.
4. This part of the brain will be made differently than the cerebrum lobes. Have
students roll out very thin (angel hair pasta) strand of ivory clay.
5. Place the strands parallel to each other on the ball of ivory clay that the
students formed for the cerebellum.
BRAIN STEM – Midbrain (concerned with visual reflexes), Pons (respiratory
fxns), and Medulla Oblongata (regulation of heart functions) – “tan” clay
1. Pons (respiratory functions) and Medulla Oblongata (contains centers
that regulate heart and functions, swallowing, vomiting, coughing, and
sneezing) are formed by making a thick strand of tan/beige clay about an
inch long. Hook the top of the strand like a candy cane.
2. Press the hook into the strand then smooth out the line in the clay. The
bubble of clay will be the “poochy” pons.
3. Place the “poochy” pons towards the face or mouth of the diagram and attach
to the front of the cerebellum.
4. Cut the strand at C2 to form the end of the Brain Stem. The strand of clay
from the bottom of the Pons to C2 is the Medulla Oblongata.
BUILDING THE SPINAL CORD – “The super highway to and from the
brain!”
1. Form a thick strand of “tan” clay about 4-5 inches long.
2. Connect the strand to the base of the Medulla Oblongata and
lay it on top of the vertebrae.
3. Cut the strand at L1 (Adult spinal cord ends at L1)
4. Place arrows in the clay going up. This represents the sensory
(afferent) tracts of the spinal cord.
5. Remind students that the sensory tracts are found on the dorsal
side of the spinal cord.
6. Form another tube of tan clay about the same diameter as the
first tube. Attach it to the Medulla Oblongata and lay it on top of
the sensory tracts.
7. Add arrows to the top strand pointing down.
8. This strand of clay represents the motor (efferent) tracts of the spinal cord.
These tracts run on the ventral side of the spinal cord.
THE CNS IS COMPLETE!
PERIPHERAL NERVOUS SYSTEM (PNS)
Building the Spinal Nerve Plexus
1. Roll out “lime green” strand of clay
(diameter of thick pasta) for the spinal
nerve roots. The change in color helps
student see that they are now building
the Peripheral Nervous System.
2. Pinch off about a half inch of clay and
fold into a “V”.
3. Attach the “V” to the side of the spinal cord around C3 and C4 (doesn’t have
to be exact)
4. Attach another “V” to the other side. Add a single strand in equal length
below the “V” on each side.
5. Once a single strand is on both sides, make another “V” and place it under the
single strand.
6. The Brachial Plexus nerve roots makes “V”, single “V”
a. The Brachial Plexus hooks up to the four nerves of the arm (is
very complex and is time consuming to build – we are going to build a
modification to represent this complex nerve “hook-ups”.
b. First roll out a piece of “yellow” clay into a strand about the same
thickness as the nerve roots.
c. Break a piece of the clay off (about a half-inch in length) and fold it
into a wide “V”.
d. Place the rest of the strand in the middle and cut to match the length.
Now “hook-up” this nerve complex to the green roots.
e. Add a single strand to the nerve complex. Cut it so that it looks like it
goes behind the clavicle. Stop the strand at the medial side of the
humerus one-third of the way down.
f. (Remind students that this yellow piece of clay represents all the
“hook-ups” for the nerves of the arm. This is just a modification
that makes things a little simpler for attaching the
nerves.)
Ulnar Nerve
1. Roll out a strand of “bright yellow” clay. Make the strand
smaller in diameter than the yellow strand that made the
modification of the nerve “hook-ups”.
2. Using a pencil form 3 holes into the belly of the Flexor
Digitorum Profundus. This is the “target for the ulnar nerve.
(fine motor movement)
3. This nerve innervates flexors on the medial and ventral side
of the arm. It travels through the brachial area, but does not
innervate or carry sensory until it is below the elbow.
4. Mark the last 3 digits of the hand with a “U”. On the middle digit, make a line
from the middle of the finger, and place the “U” on the medial side. This digit
is innervated by two nerves on the ventral side and the radial nerve on
the dorsal side. (This is the major digit for weight bearing and opposing the
thumb.
5. Attach the strand for the ulnar nerve to the end of the yellow piece of the
medial humerus.
6. Stop the strand just above (superior) to the medial epicondyle and then
restart it below (posterior) to the epicondyle. (Remind students that the
nerve goes behind this epicondyle, so we stop and start the clay to show that
it goes behind the bone. Also, remind students that hitting this nerve is
what is known as the “funny bone”.
7. Run the ulnar nerve along the ulna and stop at the wrist (carpal region).
8. Have students roll very thin strands and attach these strands to the fingers.
(Remind students that the ulnar nerve innervates the medial side of the
middle finger.)
9. Students are now going to innervate the Flexor Digitorum by placing small
strands of “bright yellow” clay into each opening and connecting the strands
to the ulnar nerve. Students finish the innervation by placing nerve branches
into all the openings.
Medial Nerve
1. Once again, have students roll out a
strand of “blue jean blue” clay. Make the
strand smaller in diameter than the
yellow strand that made the modification
of the nerve “hook-ups”.
2. Using a pencil, form 3 holes into the
belly of the Flexor Pollicus Longus.
This is the “target” for the medial
nerve. (This nerve is much like the ulnar nerve in the fact that it doesn’t
innervate until it passes below the elbow.) It innervates flexors on the
lateral and ventral side of the arm.
3. Mark the thumb and first 2 digits of the hand with a “M”. On the middle digit,
place the “M “ on the lateral side of the mark. (Remind students that this
digit is innervated by 2 nerves on the ventral side and the radial nerve
on the dorsal side.)
4. Students roll out another strand of “blue jean blue” clay (same diameter as
the ulnar nerve).
5. Attach the strand to the end of the yellow piece on the medial humerus.
6. Students run the strand straight down the middle of the arm and stop it at
the wrist.
7. Attach smaller strands to innervate the thumb, index finger, and middle
finger to the medial nerve. (Now students can see how the middle finger is
innervated with these 2 nerves!)
8. Once again, using small strands, the medial nerve innervates the Flexor
Pollicus Longus.
Carpal Tunnel
1. Using a small piece of “lightest pink” clay,
roll in to a small tube and flatten into an oval
disc.
2. Place the disc over the medial nerve at the
carpal region, but not over the ulnar nerve.
3. This connective tissue “strap” forms the
carpal tunnel. (Discuss over-use injuries
associated with hairdressers, computer
programmers, etc.)
Musculocutaneous Nerve
1. This nerve will innervate the flexors ABOVE the elbow and become just
a sensory nerve below the elbow.
2. Have students carefully roll the medial nerve to the medial side of the
Brachialis muscle.
3. Using their pencil, from only 2 openings in the belly of the Brachialis
muscle. (Only two openings for muscle that have “gross movement”. Less
innervation and brain needed to move these muscles.)
4. Roll out a strand of “coral (peachy)” clay same diameter as the ulnar and
medial nerve. Attach the strand to the end of the yellow (Brachial Plexus)
strand, and run it down the middle of the Brachialis, over the cubital, and
then stop it half-way down the radius.
5. Innervate the Brachialis using two small strands of “coral colored” clay.
Place into the openings from the belly of the muscle to the Musculocutaneous
nerve.
Remind the students that there are more nerves on the ventral side of the arm
than the dorsal side, which makes flexion dominate over extension.
Independent Student Building – Complete other arm – build the Brachial Plexus
and Nerves.
Thoracic Nerves:
Students from a long strand of “lime green” clay. The strand should be about the
same diameter as the Brachial Nerve Roots.
Begin by placing a single strand (this nerve group only uses single strands) below
the last “V” of the Brachial group. Build both sides of the Thoracic nerve group in
matching pairs (12 pairs). Each pair of nerves will be placed where there is a
vertebral disc. Cut the nerve roots so that they match the length of the Brachial
roots. (The single strand pair below the last “V” is a part of the Brachial plexus and
the pair of nerves at L1 are a part of the Lumbar plexus. If you want to be exact,
otherwise . . . just have students build them.)
Lumbar Plexus – (5 pair) The
Lumbar Plexus (lime green) has paired
spinal nerves at the lower end of the
spinal cord. After that, the pairs have
to come off the end of the spinal cord.
The connection that each nerve makes
forms the Caudal Equine, which must
have looked like a horse tail to the
anatomist that discovered and named
this structure.
(Instruct students that each nerve
MUST connect to the spinal cord. Encourage the students to make the strand really
thin so that the caudal equine doesn’t look like a large bump.)
Sacral Plexus – Roll out very thin “hot pink” clay for this plexus. Each nerve
MUST attach to the end of the spinal cord. These nerves travel down the
vertebral column, into the sacrum, and then exit out the ventral side of the
sacrum before heading posterior (ventrally) to the femur. (Can show on
skeleton with large piece of clay.)
Peripheral Nervous System
Understanding Spinal Nerves by building a Reflex Arc
1. Guide students to form a ball of ivory clay (about the size
of a cherry tomato), press the ball of clay between the
index finger and thumb to form a thick disc.
2. Form a ball of out of clay (about the size of a peanut
M&M). Roll the ball into a thick tube about 2-3 inches
long.
3. Attach the tube to both sides of the disc forming an arch.
4. Use another ball of ivory clay (size of a peanut M&M), roll
out another tube.
5. Break off a piece of the tube about ¼ inch long. Place this
piece on the side of the arch about 2/3rd’s of the way up to
the to the top of the arch (Transverse Process)
6. Then place another piece on the top of the arch (Spinuous
process)
7. Last, place the last piece on the other side of the arch . . .
mirroring the other side.
a. If students have not guessed what they are building
yet, give them some hints.
8. Have students switch to the tan clay and form a ball about the size of a peanut
M&M. Form the ball into a thick cylinder. (The cylinder fits into the vertebral
foramen and stick up in the air.
9. Have students place the tan cylinder into the vertebral foramen.
10. “What is this structure?” – Hopefully they realize it is the spinal cord.
11. Using a tooth pick have the students form the dorsal & ventral horns of the
spinal cord by forming an “X” into the top of the spinal cord.
12. Have the students locate the dorsal horn (always on the same side as the
spinuous process). Remind them that this is the “on-ramp” to the “super
highway” of the neural pathways of the spinal cord. Sensory messages ALWAYS
enter the spinal cord at the dorsal horns.
13. Have students locate the ventral horns. Remind them that these are the “off
/exit ramps” from the spinal cord. Motor messages ALWAYS exit from the spinal
cord out the ventral horns! (Great place to talk about the polio virus attacking
and harming the ventral horns of the spinal cord resulting in paralysis).
14. Using “Terra-Cotta” colored clay (size of a small cherry tomato), student will
now make a muscle) or target for the spinal nerve.
15. Roll the ball into a short thick tube. Have the ends taper down (forming a
carrot). Students now have a muscle with two tendons.
16. With the use of a tooth pick, place striations into the belly of the muscle
(remember striations should point to the attachments).
17. Place the muscle over to one side of the vertebra. (Muscle should be on the
ventral side of the vertebra.
18. Students get a “bright blue” piece of clay (size of a peanut M&M) and form it
into a ball and then roll it into a tube. Students continue to roll the tube into a
strand. This will be the sensory nerve.
19. Attach the end of the blue strand to the dorsal horn on the spinal cord. (The
strand does not have to attach to the top of the dorsal horn on the spinal cord,
but more to the back of the spinal cord.)
20. Run the blue strand towards the muscle, then cut the strand.
21. Using the tooth pick, split the end of the strand to form the receptors of this
sensory nerve.
22. Attach the “receptors” of the sensory nerve to the tendon of the muscle.
23. Using a very small piece of blue clay (size of a mini M&M), from a ball of clay and
attach it to the blue strand just outside the vertebra. This is the ganglion of the
sensory nerve.
24. Using the tooth pick, make arrows showing the direction that the messages are
being carried (to the spinal cord).
25. Using the toothpick, have students make 2 holes into the belly of the muscle.
(Motor nerve penetrates through the epimysium and goes into the muscle.)
26. Making the motor nerve will be done much the same as the sensory, except that
we will use “Orange” clay.
27. Attach the motor nerve to the ventral horn of the spinal cord. Once again, the
strand does not have to be attached to the top of the spinal cord.
28. Once the motor nerve is attach to the spinal cord, place the motor nerve next to
the sensory nerve as it heads towards the muscle. When reaching the muscle,
direct students to run the nerve over the muscle and beyond it. The strand
needs to run between the holes made in the belly of the muscle.
29. Place 2 thin strands of orange clay for the motor nerve branches that will
“innervate” the muscle.
30. The small strands are placed into the holes made in the muscle and then
attached to the main strand to show how a nerve innervates this muscle as it
passes by.
31. Place arrows in the clay showing the direction of the motor messages as they
exit the spinal cord and go to the muscle.
32. These are the “Spinal Nerve”.
33. Form a ball of “Bright Yellow” clay (size of a
small cherry tomato) into a round disc. This
will be the intervertebral disc. (This is
fibrocartilage)
34. Place this disc onto the body of the vertebra.
35. Use the “Ivory” clay to form another
vertebra. This vertebra will sit on the
“Bright Yellow” fibrocartilage disc.
Building the Sciatic and Femoral Nerve
Sciatic Nerve – This is the largest nerve on the human body
because it innervates the entire back of the leg, lower leg, and
pelvic floor.
The size of the nerve on a human is about the width of your
thumb.
1. Have students roll out a strand of “Hot Pink” and “Purple”
clay about 2 inches in length. Place the strands side by side.
The “pink” strand will go on the medial side of the nerve and
would innervate 2 hamstrings and Adductor magnus (does
not go past the popliteal). The purple strand of the nerve
will innervate the Biceps femoris and everything below the
knee.
2. Attach the sciatic nerve to the ischial tuberosity and run it to the medial side of
the femur.
3. The sciatic innervates flexors of the leg. (The posterior (ventral) side of the leg.)
Femoral Nerve
1. Use “Yellow” clay, form a strand about 3 inches long. Break off
about an inch and fold it into a “V”.
2. Place the remaining piece of the strand down the middle of
the”V” to form a “chicken foot”.
3. Add the end of each part to the three strands to the nerve roots
L2-L4 that supply the Femoral nerve. Have students build the
other side.
4. Once, they have the femoral nerves built;; add a strand of
“Brown” clay from the end of the yellow to the top (proximal)
of the femur. From here, the femoral nerve branches out (looks
like tree roots) to innervate the medial and anterior thigh
(remember this is the dorsal side of the leg).