Eye Movements Shed Light on Our Sense of Humor

Our pupils dilate the moment we realize a joke is funny

Join Our Community of Science Lovers!

We have all experienced the “aha” moment when a joke suddenly makes sense, and scientists have long tried to figure out what happens in our brain during that crucial split second. Now a researcher at the University of Michigan at Ann Arbor has found a window into that state of mind: the eyes.

Humor psychologist Richard Lewis (no relation to the comedian) was intrigued by past studies showing that a person’s pupils dilate in proportion to the funniness of a cartoon he or she is looking at. He took a closer look at this eye reflex by showing volunteers cartoons from the New Yorker magazine and using an eye-tracking device to monitor their pupil dilation and eye movements. The subjects’ pupils dilated about half a second after their gaze fell on the regions of a cartoon that were critical in making it funny—a period that is very similar to the time it takes our brain to derive meaning from words we read. “The nice thing about combining pupil dilation with eye tracking,” Lewis explains, “is that we can now pinpoint the ‘got it’ moment.”

Determining this moment with pupil dilation, which Lewis thinks is most likely a basic arousal response, could aid researchers who investigate humor-related brain activity with MRI or electroencephalography. So far scientists have found several brain areas, including the reward system, to be associated more generally with our sense of humor; it appears we do not have a distinct neurological funny bone.

On supporting science journalism

If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.

But why do we have a sense of humor in the first place? According to Lewis, psychologists are just beginning to discover its relation to other cognitive processes that seemingly lie outside the realm of the funny, such as our ability to gauge the thoughts of others. “This is all part of looking at the state humor puts you and your brain in and how that affects other things you do,” Lewis says. “This will help us piece together the puzzle of what humor is for.”

It’s Time to Stand Up for Science

If you enjoyed this article, I’d like to ask for your support. Scientific American has served as an advocate for science and industry for 180 years, and right now may be the most critical moment in that two-century history.

I’ve been a Scientific American subscriber since I was 12 years old, and it helped shape the way I look at the world. SciAm always educates and delights me, and inspires a sense of awe for our vast, beautiful universe. I hope it does that for you, too.

If you subscribe to Scientific American, you help ensure that our coverage is centered on meaningful research and discovery; that we have the resources to report on the decisions that threaten labs across the U.S.; and that we support both budding and working scientists at a time when the value of science itself too often goes unrecognized.

In return, you get essential news, captivating podcasts, brilliant infographics, can't-miss newsletters, must-watch videos, challenging games, and the science world's best writing and reporting. You can even gift someone a subscription.

There has never been a more important time for us to stand up and show why science matters. I hope you’ll support us in that mission.

Thank you,

David M. Ewalt, Editor in Chief, Scientific American