10 November 2022 • FacultySTEM Do Dogs "See" Smell?

In his latest blog on Psychology Today, Associate Professor and Chair of Psychological Science Daniel Graham explores new research on how dogs process smell differently from humans and other mammals.

Have you ever wondered what’s going on in your dog’s head? While your ponderings may focus on your dog’s levels of affection for you, the content of their dreams, or their favorite foods, you may not have considered how they smell those foods. Dogs are known for their strong noses, but new research suggests that their vision systems play a key role in their sense of smell. In his latest blog on Psychology Today, Associate Professor of Psychological Science Daniel Graham details new research from Cornell University Veterinary College that explores differences in how dog brains process smells.

To start, there are key differences in anatomy between how humans and dogs experience smells while eating. When humans chew food, we experience a process called retronasal olfaction, where gasses escaping the food travel up into our nasal cavity via the back of the throat. This process is where much of the “flavor” we experience comes from. Dogs, on the other hand, have little anatomical room for backward airflow. “With the flavor-constructing function of smell demoted, dog noses are instead built around mapping out and identifying the smells all around them,” explains Graham.

The new Cornell research has found “extensive connections between the olfactory bulb, which receives signals from the nose's olfactory sensory neurons, and the occipital lobe, which houses the visual system,” Graham writes. The connections between the two regions were thick, occupying about one percent of the dog’s entire brain. These findings, Graham explains, suggest “dogs integrate smell information early on in the processing of the visual world.”

“Perhaps it is something like the way objects around us have visual form and identity, as well as a distinct feeling or vibrancy of color,” writes Graham. “We can't peer inside their heads to see what it feels like to be a dog, but it must be a world full of vivid smells.”

Read the full article here.

Graham holds a B.A. in physics from Middlebury College and an M.S. in physics and Ph.D. in psychology from Cornell University. A member of the HWS faculty since 2012, his research focuses on both human and mammal brains from varying approaches, including computational, behavioral, and theoretical approaches, with a focus on vision coding. His book, An Internet in Your Head, published by Columbia University Press, explores the Internet as a metaphor for the human brain. Follow his blog on the same topic, “Your Internet Brain” here.