In the summer of 1980, I had finished my first year of college and was excited to have been accepted as a volunteer in a laboratory studying the basis of pain sensation in the brain. This group, directed by a creative, wise and kind researcher at UCLA named John Liebeskind, was my first lab home. It represented a big step up from my previous summer’s employment: cooking for late-night drunks and stoners at Shakey’s Pizza Parlor, to the maddening accompaniment of a ragtime piano loop tape. I was feeling very nervous and was desperate to make a good impression on the “real scientists” in the lab.
The Liebeskind lab, like many others at that time, was interested in how morphine-like molecules produced within the body (called endorphins and enkephalins) functioned to blunt pain perception. The experiment that was assigned to me was to perform surgery on rats to implant hollow metal needles into a location in their brains thought to be involved in pain perception (called the periaquaductal gray area). Then, after the rats recovered from their surgery, I was to inject tiny amounts of endorphins, following which I would use a standard test to measure how much pain the endorphin-injected rats would feel. The responses of these rats would be compared with a control group that had only a saline solution injected into their brains.
The standard test I used was called the “hotplate test” and it’s pretty much what you might imagine. A hotplate with foot-high walls built around the edge was turned up to an uncomfortable but not damaging temperature. The rat was gently placed on the hotplate and the experimenter (me) stood there with a stopwatch to time how long before the rat would feel enough heat on its paws to jump. The data that come out of this sort of experiment are plotted as a bar graph with the experimental group on the x-axis (endorphin-injected or control) and the “time to first jump” on the y-axis.
After weeks of surgery, I had a bunch of rats ready to go. I had my special syringes full of drugs to inject into the brain. I had my white lab coat, clipboard, stopwatch and a way-serious attitude. Injecting the rats went without a hitch. Then I placed the first one on the hotplate and clicked the stopwatch. My very first experiment was starting. I was about to collect some honest-to-God data. Hot damn!
Well, the rat sniffed around, looking more and more agitated. Then, I swear to you, it looked up at me and did the closest thing a rat can do to a grin. This rat was not going to hop and he had a plan. The clever rodent peed and peed until a huge puddle formed on the hotplate. Then he (for it was a male rat) stood in the puddle. With my mouth hanging open I dutifully clicked the stopwatch. While I’m sure it didn’t actually happen, in my mind I heard a little voice squeak “Ha! Plot that on your graph Mr. Scientist!”
So I did. I made a very official-looking graph, the y-axis of which read “latency to pee and stand in it (seconds)” and rode the elevator up from the basement lab to John Liebeskind’s office. I reverently handed over the data from my very first experiment and waited. He started with a low chuckle which gradually built up to all-out howls of laughter that were so infectious that I joined in, at once embarrassed and delighted. When we had calmed down he said, “Yeah, that happens sometimes. I should have warned you!”