21 March 2013
A Funny Thing Happened on the Way to the Cornea
Today, my assistant B. asked me about a patient's cranial nerve injury. He had learned about the cervical, thoracic and lumbar nerves, but never those that connect the brain to the spinal cord. I pulled out my trusty Anatomy Coloring Book en français and turned to the section on the brain.
There were wonderful black-and-white sketches of what each of the twelve cranial nerves control, and when we talked about the pupil of the eye he asked 'what is that?'
'You know, the black hole in the middle of your eyeball.'
He stared at me.
'You know, the little black hole in the iris?' I explained
'What's an iris?'
'The colored part.'
'Oh, like the ones you have!'
'You have them too.'
'No I don't,' he said.
'Sure you do!' I insisted.
'Only white peoples' eyes have color.'
'Huh? Your eyes have color, they just happen to be dark brown . . . but that's just as much of a color as blue.'
He didn't believe me.
'Anyway, that's not the point, the point is, in the middle of your dark brown iris, there is a little hole that gets bigger and smaller based on the amount of light in the room.'
'THE HOLE GETS BIGGER?' he asked, certain I was the craziest person he had ever met.
'Yup! It changes size to control how much light goes into your eye in order to protect the retina as well as to be able to see when you're in a dark room.'
He didn't believe me. 'I've never heard of ANYTHING like that before! Eyeballs don't get bigger or smaller!'
I tried again to explain that it's the iris that contracts or expands, and not the whole eyeball, but I knew we weren't going to get anywhere if I didn't have some sort of tangible teaching aid.
'Come with me.' I said as I turned to go into our storage room. I switched off the light and handed him my cell phone. 'Push this button, then slowly pass the light before my eyes and watch what happens.'
He lifted the phone level with my ears and started to inch it towards my face.
'KAI!!!!!' he shouted (that's Hausa for 'WHAT THE CRAP!') and nearly dropped my phone. In awe at my amazing shrinking irises, he did it again . . . and again . . . and again.
'I've never seen ANYTHING like that before!'
As I shared in his thrill of new learning, I began to think to myself about all the knowledge I take for granted . . . the simple things which I have filed away in my subconscious that I acquired somewhere along the road of my learning process: all humans have irises and pupils . . . 'pupil' comes from the Latin word for 'doll' . . . 'pupil' is also a synonym for 'student' . . . a 'synonym' is a different word with the same or similar meaning . . . a synonym for 'synonym' is 'alternative' . . . which I read in a thesaurus . . . which I learned how to use in school . . . which I attended because I come from a culture that values education for girls . . . .
And then I wondered when was the last time I had my own 'KAI!!!!!!' moment . . . when learning something new was so precious and valuable that it blew my socks off . . . wait . . . when was the last time I wore socks??