| If everybody’s doing it…

Each fall, 30,000 scientists from around the globe gather in one of the four U.S. cities with a convention centre capable of holding such a large crowd to talk about the brain. The conference, simply called Neuroscience, is like a big science fair, but instead of sweaty, pimply-faced high school students presenting baking soda and vinegar-powered volcanoes, you get sweaty, pimply-faced graduate students presenting Ph.D. theses. It’s typically a subdued affair, but at the 2005 conference, for about 15 seconds, all that changed.

That year, Neuroscience was held in Washington, D.C., and the organizers had made the controversial decision to let the Dalai Lama give the keynote address. Many thought that the Dalai Lama, with no formal science training, was a poor pick for the keynote speaker of a prestigious scientific conference; some even signed a petition in protest. It was agreed that the talk had to be seen, and when the day arrived, several thousand scientists – this writer included – flooded the Walter E. Washington Convention Center to try to get a seat.

Soon, a crowd thick with glasses, pocket protectors, and bad haircuts had queued orderly outside the lecture hall, waiting to be let in. Everyone secretly scoped out each other’s scientific credentials, prominently displayed on their conference badges – Ph.D.s were in the majority. And then, swiftly – almost silently – everything changed. A rumour spread down the line: There were not enough seats in the lecture hall; some people wouldn’t be let in. The crowd became uneasy. A Ph.D. pushed past security; another followed and then a handful more. Suddenly someone shouted “Everybody run” and, in an instant, some of the smartest people on the planet turned into a pack of wild animals.

Behaviour can be contagious. A random drop in the price of a stock can cause a rapid sell-off that leads to the stock crashing. If you see someone yawn, or even read the word “yawn,” you are more likely to yawn yourself in the following minutes. When a group of people observe someone else’s behaviour and decide to copy it, social psychologists refer to this as an “information cascade.” Information cascades can be both good and bad. If the person sitting next to you in class is a straight-A student and she takes down a note you ignored, it might be a wise idea to jot it down as well. Cascades become dangerous, however, when they are driven by misinformation.

Last year, nearly 10,000 people in the U.S. died from swine flu. At first glance, this is a frightening number. When reported by the media, it caused a run on the vaccine at many doctors’ offices across the U.S. and Canada. But this particular information was irrational: more than 40,000 people die in the United States each year from the regular flu – an important piece of information that, if circulated with the swine flu death total, might have prevented unnecessary panic.

Back in 2005, waiting to see the Dalai Lama, I believed the rumour that there wouldn’t be enough room. And when someone shouted “Everybody run,” I joined the pack, straight past security into the massive lecture hall, which, as it turned out, was nearly empty and easily seated everyone that had come to see the show.

Daniel Lametti’s column will be back again in three weeks. Writing to him is also contagious. Try it: thesplitbrain@mcgilldaily.com.