23 year old girl scientist, happily married to a man in uniform. In my 2nd year of my PhD, new home owner, and owner of 1 dog and 2 cats.

Saturday, January 22, 2005

Just like chicken...

It was very heavy and felt just like a brain should. All the little bumps (they are called gyri) and crevices (they are called sulci) were so perfect and defined. There's a name for each section, subsection, and brainstem bump. Hundreds and hundreds of names. Brains aren't the gray, gooey slime balls depicted on TV. They are firm and specific, a tight ball of beige-colored tissue. The protective coverings cling to the brain despite efforts to peel them away. The outermost covering, the dura, looks exactly like the pig ears I feed Murphy.

My brain was sliced around the middle in a perfect circle where the coroner had slipped while sawing the skull.

I can understand why stroke victims have such specific symptoms. Two areas on the left of the brain, Wernicke's area and Broca's area, are used for speech comprehension and speech articulation, respectively. That's why if someone has a stroke in that general part of their brain, they have slurred speech or trouble understanding people.

The human spinal cord was so small and delicate. With all the bones and protective dura removed, it was merely a long, flat piece of tissue, about as big around as my ring finger. The cervical sections (of the neck) were so short, I questioned if I had a child's spinal cord, but my prof. told me it looked like a normal female, about my size. Wow. At the very end of the cord is the cauda equina (latin for horses tail), where the cerebrospinal fluid ends (around Lumbar Vertebrae 2) and the nerves begin. This is what looked like chicken to me. The pulled chicken one might add to a flavorful, richly seasoned pot of chicken gumbo. The nerves were a big jumble, large and twisted and the beige color of boiled chicken.

I was captivated for the entire two hours, lifting and poking and identifying the structures I'd memorized from my textbook. Finding the 12 cranial nerves was almost impossible, as the delicate nerves had been lost in the transition from body to jar of formaldehyde. In addition to my entire brain (which weighed about 8 pounds, and apparently was abnormally large), I had a half a brain (this way I could identify the ventricles, corpus collosum, thalamus, etc.), an intact brainstem, a severed brainstem, and a bucket of preserved cross-sections of brain. My bucket of preserved cross sections was very old, and had the beginnings of mold around the corners of some of the pieces.

A few times during my dissection, I thought about the huge brain and tiny brainsections. The sections were small and probably belonged to a child or very old, small woman. I wondered about the thoughts and emotions that once flew through these neurons and synapses. Identifying the primary sensory cortex made me wonder if the woman had felt intense pleasure many times in her life. I hoped so. As morbid as it sounds, it enforced my belief in organ donation. All 20 of us students in that room left with a renewed appreciation and enhanced knowledge of the central nervous system and brain. I'll never forget the feeling of the 4 bumps on the back of the brainstem, the superior and inferior colliculous, that make you turn your head when you see a bright light or loud sound, respectively. I'll always remember how the optic nerve twists and turns throughout the inside of the brain, traveling to signal and process the sights we see. Or how females have a larger corpus collosum, which is a reason we integrate so many of our logical decisions with emotions. I learned many homosexual men have larger corpus collosums. That explains a lot. I wonder if it's used in fashion sense too?

**Francine, correct me if I'm wrong about any of these terms or anything!! :)


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