Lexy Stang, Science publishing assistant, explains to visitors to the 4th USA Science & Engineering Festival that they may process the same sounds differently than their neighbor. | Andrea Korte/AAAS
More than 60 AAAS volunteers challenged curious visitors at the 4th USA Science & Engineering Festival to rethink their assumptions about the five senses: hearing, sight, smell, taste, and touch.
The expo drew hundreds of thousands of attendees to Washington, D.C., for a sneak peek on 15 April and the full festival 16-17 April, which featured more than 3,000 exhibits, experiments, performances, and discussions.
AAAS, a sponsor of the festival, brought its interactive “Science of the Senses” exhibit, where AAAS employees and other supporters guided visitors through activities to stimulate their senses.
One activity allowed visitors to better understand their “nose print.” Much like a fingerprint, our sense of smell is unique to us, said Casey Trimmer of the Monell Center, a scientific institute in Philadelphia dedicated to interdisciplinary research on the senses of smell and taste.
To demonstrate, Trimmer had visitors sniff several different bottled smells, some sweet and some less so. When taking a big whiff of bottled body odor, for instance, Trimmer said that some people understandably reacted strongly to the smell, wincing and taking a big step back. Others, however, were surprised to learn they couldn’t perceive the smell at all.
“It varies a lot between people,” Trimmer said, as genetic variation affects our perception of odors.
“We all experience our olfactory world very differently,” she said.
A young visitor to the USA Science & Engineering Festival learns about optical illusions by deciding whether he sees a cat's face or a mouse's. | Andrea Korte/AAAS
At the table devoted to sight, Kirstin Fearnley, AAAS Education and Human Resources program associate, guided young visitors through a series of optical illusions, including an elephant with an indeterminate number of legs, a fork with either two or three prongs, and an animal face that included both a rat and a cat.
As some children debated what they saw, Fearnley shared the secret: “There’s not actually a right answer,” she told them.
Instead, Fearnley said, these illusions demonstrate “the difference between what your eyes see and what your brain processes.”
Lexy Stang, a publishing assistant at Science, walked visitors through several auditory illusions designed by Diana Deutsch, professor of psychology at the University of California, San Diego.
Visitors sat down with a pair of earbuds to listen to the Phantom Words illusion, in which two overlapping words are repeated over and over again, from which many people begin to hear distinct words and phrases. They also heard a Shepard tone, a series of notes that appear to get higher and higher, and the Tritone Paradox, a pattern of two notes that some people hear as going up in pitch and others hear as going down in pitch.
While listening to the Tritone Paradox, children gave a thumbs-up or a thumbs-down depending on which they heard and were surprised to find that, even though the same sounds emanated from everyone’s earbuds, they heard completely different things than their neighbors.
“It’s really cool to watch them realize that,” Stang said.
Visitors could also challenge their sense of taste by eating a jelly bean with a plugged nose and attempting to guess the flavor without the benefit of scent, an experiment that demonstrated the close connection between taste and smell. At the table devoted to touch, visitors used Braille to decode a secret message and attempted to identify a small toy hidden inside a felt-lined box using only their fingers.
AAAS Education and Human Resources Program Director Bob Hirshon created the “Science of the Senses” exhibit for the 2012 USA Science and Engineering Festival and has refined elements over the years.
“The original hearing demonstration required volunteers to explain each phenomenon to visitors, and they’d lose their voices after an hour—the festival is just too noisy,” explained Hirshon. “This year, I recorded the explanations along with the audio samples, so volunteers would just have to answer questions.” He simplified the other demonstrations as well, to keep the large festival audience —estimated at more than 350,000 – moving through the five activity areas.
AAAS’ exhibit was supplemented by representatives from the AAAS/Senior Scientists and Engineers STEM Volunteer Program, which brings 175 working and retired scientists, engineers, and mathematicians into public school classrooms in the Washington, D.C., area throughout the year to supplement students’ understanding of science, technology, engineering, and math.
Morris Aizenman, who is retired from the National Science Foundation’s Directorate for Mathematical and Physical Sciences, shared information about the program with festival attendees, handing out information about the program to interested teachers and administrators and encouraging potential volunteers to “meet with some kids and enrich your life.”
Volunteers perform a range of duties in the classroom, such giving presentations and answering questions about their field and developing activities in conjunction with teachers for their students, who Aizenman said “will knock your socks off – they know so much.”
“I’ve never had so much fun,” he said of the program.
AAAS encouraged interaction between scientists and students during the “Meet the Scientists & Engineers” sessions held on Saturday and Sunday. Scientists were on hand to explain their work to festival visitors and take questions from the audience.