At the east end of the University of Arizona’s 7.5 acre grass mall is a Carolina sphinx moth fit snug in a blue plastic tube with its insect head sticking out. Two electrodes, one placed on the left eye and the other in a tiny clear plastic tube surrounding the moth’s right antenna. The electrodes are hooked up to a portable screen that displays the measured electrical activity of the moth’s antenna. Each antenna houses a quarter million primary sensory neurons that allow the moth to sense its environment. In this case, the environment happens to be engulfed in the smoky smell of barbecued ribs coming from the BrushFire’s BBQ co. tent next door.
The sphinx moth might also be able to detect other scents floating around Tucson’s eighth annual Festival of Books event. The blue raspberry flavoring of Hawaiian shaved ice, a mom’s perfume, that new book smell, pollen, dust, an author’s body odor, the smell of warm plastic from a human anatomy model sitting out in the sun. Among the scheduled visits of authors, local business vendors and organizations, the Festival of Books also hosts “Science City.” Different departments from the College of Science use the two-day event to set up outreach booths, demonstrations, performances and activities for Tucson’s general public.
Dr. Hong Lei, an associate research scientist with the University of Arizona’s neuroscience department, stands behind his moth apparatus waiting for interested children and adults to observe brain research in action. Lei squeezes a pipette filled with flower scented air onto the sphinx moth’s antenna. Even with the interfering stench of BrushFire's pulled pork, he’s still able to get the dancing line on the screen to dip down with each puff of air.
“See. That means this moth uses its antenna to smell,” he said.
Of course there’s more to it than that. Of all people, Lei should know, as his research is centered on the neurobiology of olfaction and behavior using this exact species of moth. The goal of this demonstration isn’t to go into the details of Manduca sexta neurobiology.

“We also want them to feel comfortable to ask about how the brain works.”
Oland has coordinated Science City’s neuroscience outreach component for the past six years now. Every year she helps plan about 15 brain-related booths with the help of other faculty and graduate students within the School of Mind, Brain and Behavior so that local Tucsonans of any age are able to find something to learn and feel curious about.

From there, guests can move on to other booths that test proprioception (our sense of body position in space) or visual adaptation. A brain-hat undergrad uses a handheld back massager to stimulate the tendon under the elbow so that guests overestimate the proximity of their finger when they bring it as close to their nose as they can with their eyes shut. The visual adaptation booth dares challengers to toss three beanbags at the center of a wooden target two yards away. Another brain-hat undergrad gives them prism glasses that shift their visual field slightly to the left. Asked to hit the target again, the challenger usually misses the target but gets close by the third beanbag. Unbeknownst to them, they’ve adapted to their shift in vision. When asked to try one final time without the prism glasses, guests are shocked to find their aim is dramatically off to the left.

“We get lot’s of grandparents shepherding grandchildren,” Oland said. “It’s an intergenerational experience where the grandparents are having the chance to learn themselves and show their little kids that they’re also interested in learning about this stuff too.”
When grandpa’s jaw drops, his granddaughter’s jaw drops too. Smiles often follow. Oland loves to see it. She says the kids are learning by example.
References
Sanes, J. R., & Hildebrand, J. G. (1976). Structure and development of antennae in a moth, Manduca sexta. Developmental biology, 51(2), 282-299.