The Brain: Our Navigation Diamond.

We have finally made it to the brain!!! We can say so long to muscles for now but don't forget them too fast! The midterm exam is coming up in a couple of weeks. So keep up the studying and don't forget to start reviewing now! It truly is amazing how complex the human brain is. With a total weight of about 3 pounds, it is the initiator of practically everything we do in a days work. From the very moment one gets out of bed to the many hours one puts into this class, the brain is highly active and always working overtime. Did you know the brain is still functioning even while we sleep? It never takes a break!!! On average, information in your brain travels at a rate of about 268 miles per hour. Also, it is estimated that the brain has 100 billion nerve cells and more connections in it than there are stars in the universe, which is about the number of stars in the Milky Way Galaxy. Wow, the brain never ceases to amaze me!

This week in lab, our focus is the Central Nervous System. This system consists of the brain and the spinal cord. A good chunk of the terms you have probably heard before, but most are very new and unfamiliar I am sure. Whatever the case may be for you, with enough time and practice you will know more about the brain than ever before in your entire life. So with that, here are some tips and helpful mnemonics for you to use in your studies.

Week 5 Study Tips

1. The models are helpful, but make sure to study off of the specimens. Learn as many terms from as many brain dissections as you can. You are most likely going to be quizzed on the dissections only. Begin by orienting yourself by way of the models. As you get better and more advanced, move onto the specimens.
2. The Brain can be pinned from all sorts of angles. Think back to the very first week of anatomy. The body regions and planes were taught and we learned about the coronal and sagittal planes. These types of cuts are very popular to use in lab quizzes. If you can't find a good sagittal or coronal cut, talk to a TA and they will be able to pull out a good specimen to show you. There are some tricky pins in regards to this week. Be creative as you study!
3. Be very gentle with the brains! Brain tissue is very delicate and tears easily. Many, many hours go into preparing a brain specimen. Spray them frequently and be sure not to poke at them. One bad tear and overtime, a brain specimen will become harder and harder to learn from.

**So here are some terms for the week and ways to remember them!!!

Cerebrum: Cerebro (X-men) sits on your cerebrum...or just think the biggest part of the brain.

• Genu: the genius' sit in the front
• Splenium: it's splendid to sit in the back

Cerebellum: sits at the base of the Cerebrum

• Arbor Vitae: "Tree of Life" - resembles a tree
  
• Vermis: Vermin that peeks out of his hole - the connection between the two cerebellar hemispheres

The "Duck" Picture

• Thalamus: duck's head
• Interthalamic Adhesion: duck's eye
• Hypothalamus: duck's beak
• Infundibulum: straw coming out of the duck's beak
• Pituitary Gland: bubble on the end of the straw, if the duck were to spit he would saw "pituey"
• Pineal Gland: feather on the back of the duck's head. You will be able to study this structure best on a sagittal cut brain and a brain with a removed cerebellum.

**Or another way to think about the infundibulum and the pituitary gland - it is FUN to blow bubbles!!!

The Troll/Patrick the Star Fish Picture (The one you have all been waiting for!!!)

• Pons: Troll's body
• Medulla Oblongata: Troll's head
• Cerebral Peduncles: Troll's legs
• Cerebellar Pedencles: Troll's arms
• Corpora Quadrigemina: Troll's calfs (Gastrocnemius)

The Spinal Cord

• Anterior Median Fissure: All Men Fear
• Posterior Median Sulcus: P-M-S

Gray and White Matter

• The Brain is like a Twinkie: Gray Matter on the outside (cake), White Matter on the inside (cream filling).
• The Spinal cord is like a corn dog: Gray Matter on the inside (meat), White Matter on the outside (bun).

**Remember: Gray Matter consists of axon cell bodies and White Matter consists of myelinated axons. In the brain, there are nerve impulses going into it, and in the spinal cord there are nerve impulses going away from it.

Meninges: The covering of the brain

• Dura Mater: tough mother
• Arachnoid Mater: spider-like
• Pia Mater: gentle mother

**Note: The Pia Mater cannot be physically separated from the brain tissue. If pinned on a quiz, there will be a pin going into the brain and a question asking, "What mater is the pin going through?"

Reflex Arc

• Sensory Afferent Neuron: sense someone looking at your back.
• Motor Efferent Neuron: drive a motor-vehicle in the front.

Remember to think SAME DAVE

• Sensory Afferent, Motor Efferent
• Dorsal Afferent, Ventral Efferent

Ventricles: producers of Cerebral Spinal Fluid

• Lateral Ventricle: Inside the space of the corpus callosum
• Septum Pellucidum: Membrane sheath that divides the two lateral ventricles
• Third Ventricle: Around the Thalamus
• Fourth Ventricle: Anterior to the Cerebellum
• Mesencephalic (Cerebral) Aqueduct: Tube connecting the third and fourth ventricles
• Choroid Plexus: Tiny grape-like structures, found in the ventricles, that make cerebral spinal fluid.

**I hope this helps. Good luck studying this week and don't forget to review for the midterm and little bit every day. Happy Studying!!!

Fun Fact for the Day:

• The Superior Colliculus, of the Corpora Quadrigemina, is responsible for turning our head with a sight we see.
• The Inferior Colliculus, of the Corpora Quadrigemina, is responsible for turning our head with a sound we hear.