Researchers at The John B. Pierce Laboratory and the Yale School of Medicine have revealed that the ability to vividly imagine the smell of popcorn, freshly baked cookies and even non-food odors is greater in obese adults. Their research was published in the journal Appetite in August 2015 and was presented at the Annual Meeting of the Society for the Study of Ingestive Behavior (SSIB), the foremost society for research into all aspects of eating and drinking behavior.
All of us can imagine the view of a favorite spot or sing a song to ourselves. Not so with imagining odors. People vary greatly in their ability to imagine the smell of freshly baked bread or the sweet aroma of a bouquet of roses. This raises the possibility that differences in the ability to imagine odors, especially food odors, might be related to the frequency with which food cravings are experienced. According to Kavanagh’s Elaborated Intrusion Theory of Desire, vivid mental imagery is a key factor in stimulating and maintaining food cravings, which can be induced by the thought, smell and sight of food. Although previous research demonstrate that food cravings occur more often in obese individuals, the relationship between the ability to imagine odors and body weight has not been examined. If individuals with higher body weights report a heightened ability to imagine odors, this may intensify the food craving experience through the creation of more vivid images of flavors and aromas
In the study, participants completed a series of questionnaires that asked them to imagine both visual and odor cues and then to subsequently rate the vividness of these cues. The researchers found that individuals with a higher body mass index (BMI) reported greater perceived ability to image food and non-food odors.
“These findings highlight the need for a more individualistic approach in identifying factors that may increase risk for weight gain,” said Dr. Barkha Patel, study lead author and Postdoctoral Fellow. They also call for “future work to assess imagery ability directly rather than relying upon self-report measures,” said Dr. Dana Small, senior author and a Professor of Psychiatry at the Yale School of Medicine and Deputy Director at the John B. Pierce Laboratory.
For more information:
Greater Perceived Ability to Form Vivid Mental Images in Individuals with High Compared to Low BMI. BP Patel, K Aschenbrenner, D Shamah, DM Small.
Dana M Small
Tel: 203-562-9901 x272
By Ed Stannard, New Haven Register
Posted: 10/29/15, 1:19 PM EDT
NEW HAVEN >> Understanding the sense of smell could help in building robots to do things we rely on animals to do today, such as locating people under the rubble of an earthquake, locating illegal drugs or finding a bomb.
That’s the quest of a study at the John B. Pierce Laboratory and Yale School of Medicine, one of three underwritten by the National Science Foundation, part of President Barack Obama’s BRAIN Initiative (BRAIN stands for Brain Research through Advancing Innovative Neurotechnologies).
“There have been some studies on this problem of understanding olfaction,” said Justus Verhagen, associate fellow at the Pierce Lab and professor in neurobiology in the School of Medicine. However, “a single lab can only look at so much.”
In fact, we know “close to nothing” about the sense of smell in mammals, he said.
The team at the Pierce lab, which is affiliated with the School of Medicine, has “a mathematician, three neuroscientists. We have an evolutionary behaviorist. We have a physicist on board who actually images odor plumes,” Verhagen said.
The study will use animals such as snails, flies, mice and dogs to see how they react to an “odor plume,” which is “the concept of what an odor source looks like in space and in time,” Verhagen said.
As an odor emanates from a flower, for example, it enlarges in space and gets more diffuse, but not in a regular pattern. “It’s a little like crumpled-up paper [with] a lot of voids” where there is no odor at all.
While rats and dogs are used to find survivors underneath a collapsed building or to locate drugs in a school locker, they’re “highly unreliable,” according to Verhagen. Another application is tracing chemical pollutants in a body of water, he said.
The animals in the study will range from snails to dogs and their movements will be measured as they follow virtual odor plumes, which are created in the lab to simulate actual odors. “For example, a mouse will run on a trackball suspended on air to trace its movements and measure its brain activity as it tries to find the source of a virtual odor plume,” Verhagen said.
Also, the mice’s brains will be stimulated by light to detect how the olfactory centers in the brain respond to odors.
The projects arose from an intense workshop held in June at the Janelia Research Campus in Virginia, a farm that is part of the Howard Hughes Medical Institute. A total of 140 scientists competed for the projects funded by the National Institutes of Health.
“If you understand the problem in biology you can really apply this for the good of humankind,” Verhagen said.
Justus V. Verhagen, associate fellow at the John B. Pierce Laboratory, and Yale neurobiologist, is one of 17 researchers nationwide to receive grants totaling $15 million from the National Science Foundation to study how the brain processes and identifies odors.
The grants announced September 21, 2015 are an outgrowth of the President’s Brain Initiative and will fund three separate multi-disciplinary research efforts. Dr. Verhagen and colleagues from five other institutions will study how animals – from flies to humans – use olfaction to find resources, such as food and mates. They hope to understand how such different creatures, with such different brains, all share this ability to odor navigate.
They will use odor plume physics, neurocomputation, and behavioral neuroscience to tackle this long-standing problem. Verhagen will pioneer a virtual odor navigation task coupled with optical imaging and optogenetics.
“Olfaction is both an important and tractable problem in neuroscience,” said James Olds, assistant director of the Biological Sciences Directorate. “By using the olfactory system, which is an ancient system, as a model for neural circuits, we can gain insights into the fundamental principles underlying neural activity and complex behaviors.”