Featured Post from University of Florida

Study: What makes a smell bad?

Jan 29, 2026

3 min

You wouldn’t microwave fish around your worst enemy — the smell lingers both in kitchen and memory. It is one few of us like, let alone have positive associations with.

But what makes our brains decide a smell is stinky?

A new study from UF Health researchers reveals the mechanisms behind how your brain decides you dislike — even loathe — a smell.

Or as first author and graduate research fellow Sarah Sniffen puts it: How do odors come to acquire some sort of emotional charge?

In many ways, our world capitalizes upon the importance of smells to influence emotions, running the gamut from perfumes to cooking and even grocery store design.

“Odors are powerful at driving emotions, and it’s long been thought that the sense of smell is just as powerful, if not more powerful, at driving an emotional response as a picture, a song or any other sensory stimulus,” said senior author Dan Wesson, Ph.D., a professor of pharmacology and therapeutics in the UF College of Medicine and interim director of the Florida Chemical Senses Institute.

But until now, researchers have puzzled over what circuitry connects the parts of the brain vital to generating an emotional response with those responsible for smell perception.

The team started off with the amygdala, a brain region that curates your emotional responses to sensory stimuli. Although all our senses (sound, sight, taste, touch and smell) interact with this small part of your brain, the olfactory system takes a more direct route to it.

“This is, in part, what we mean when we say your sense of smell is your most emotional sense,” Sniffen said. “Yes, smells evoke strong, emotional memories, but the brain’s smell centers are more closely connected with emotional centers like the amygdala.”

In the study, researchers looked at mice, who share neurochemical similarities with people. They can learn about odors and categorize them as good or bad.

After observing their behavior and analyzing brain activity, the team found two genetically unique brain cell types that allow odors to be assigned into a bucket of good feelings or bad feelings.

Initially, the team expected that one cell type would generate a positive emotion to an odor, and another would generate a negative emotion. Instead, the brain’s cellular organization gives the cells the capability of doing either.

“It can make an odor positive or negative to you,” Wesson said. “And it all depends upon where that cell type projects in your brain and how it engages with structures in your brain.”

But why is knowing more about how we categorize smells important? Well, for starters, smells — and our reactions to them — are a part of life. Sometimes, however, our reactions to them can be outsized, or take on a negative association so strong it disrupts how we live.

“We’re constantly breathing in and out and that means that we’re constantly receiving olfactory input,” Sniffen said. “For some people that’s fine, and it doesn’t impact their day-to-day life. They might even think, ‘Oh, odors don’t matter that much.’ But for people who have a heightened response to sensory stimuli, like those with PTSD or anxiety or autism, it’s a really important factor for their day-to-day life.”

In the future, the research could help clinicians adjust for heightened sensory response that some people struggle with in their everyday lives, Wesson added. One example? A patient associating a clinic’s smell with transfusions that made them queasy.

Based upon the receptor systems in these specific brain pathways, the team members believe they might be able to change those associations.

Potentially, medications could suppress some of these pathways’ activity to allow you to overcome stressful and aversive emotional responses.

Conversely, these pathways could be activated to restore enjoyment to things that people might have grown indifferent to — like those who lose their appetite from illness.

“Emotions in part dictate our quality of life, and we’re learning more about how they arise in our brain,” Wesson said. “Understanding more about how our surroundings can impact our feelings can help us become happier, healthier humans.”

This research was supported by funding from the National Institute on Deafness and Other Communication Disorders and the National Institute on Drug Abuse. Sarah Sniffen was supported by a fellowship from the National Institute on Deafness and Other Communication Disorders.

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Daniel Wesson

Associate Professor | Chair

Daniel Wesson is an expert in the sense of smell and how the brain processes sensory information.

AddictionBrain FunctionElectronic CigarettesSensory ProcessingSmell, Learning & Memory

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Mar 30, 2026

3 min

UF researchers aim to improve nutrition for cancer patients

A new study and first-of-its-kind food pharmacy at UF aim to help patients with cancer access and eat nutritious foods, giving them the best possible shot at a healthy future. As many as a third of cancer patients face food challenges, particularly in rural areas. Good nutrition can improve outcomes during and after treatment. With a grant from the Florida Department of Health, a team of researchers at the University of Florida Health Cancer Center and Sylvester Comprehensive Cancer Center will first assess the community’s nutritional needs. Then they’ll test the usefulness of a food-focused digital tool designed to connect patients to helpful resources. An on-site food pharmacy will help patients not only get the food they need to thrive but also provide tools for lasting change. “We’re taking a community-based approach to holistic cancer care,” said Dejana Braithwaite, Ph.D., associate director for population sciences at the UF Health Cancer Center. “Patients consistently express that nutrition is an important issue for them during cancer treatment. We want to address nutritional needs from treatment through survivorship with a sustainable intervention. ASCENT brings science and community together to make that a reality in Florida.” Braithwaite, a professor and division chief in the UF Department of Surgery, is leading the multi-institution study with Tracy Crane, Ph.D., R.D.N., director of lifestyle medicine, prevention and digital health and co-lead of the Cancer Control Program at Sylvester, part of the University of Miami Health System. Researchers from the UF colleges of Journalism, Medicine, and Public Health and Health Professions and UF/IFAS Extension are participating. The Florida Partnership for Adding Social Context to Address Cancer Survivorship Outcomes study, which the researchers have nicknamed ASCENT, will focus on those affected by the most prevalent cancers in Florida, including breast, lung, colorectal, prostate and blood cancers. “Cancer survivors who follow a healthy dietary pattern have a lower risk of recurrence and death,” said Cora Best, Ph.D., R.D.N., an assistant professor of nutritional sciences in the UF College of Agricultural and Life Sciences and study team member. “Some cancer therapies have long-term or late side effects that increase the risk for chronic conditions, like osteoporosis, which can be alleviated with good nutrition. That means a healthy diet during and after oncologic treatment can enhance lifespan and quality of life.” Researchers will start by conducting interviews with patients, providers and community-based organizations. They want to understand how to best use resources to meet the nutritional needs of those with cancer, such as food security and diet quality. “Community outreach and engagement with various groups is a cornerstone of the study,” said Francis Dalisay, Ph.D., an associate professor in the UF College of Journalism and Communications who helped develop the interview guides. The team will use the information to build a diet intervention with online surveys and patient navigator support, which they will test in a randomized clinical study at UF Health and Sylvester. Patient navigators will connect patients with resources like community programs or specialist referrals. The food pharmacy, located at the UF Clinical and Translational Sciences Metabolic Kitchen, will help cancer patients get healthy, whole nutrient-dense foods like high-protein items, fruits, vegetables and pantry staples. It will also provide workshops, personalized recipes and meal plans. Although the United States is a wealthy nation, food insecurity remains common, including in Florida, Best said. “The ASCENT study pairs evidence-based dietary guidance for cancer survivors with innovative strategies to overcome barriers like food insecurity,” she said. Ultimately, the study aims to empower patients so they can address lifestyle factors in their control, boosting their well-being. “I am hopeful this study will provide patients with appropriate resources to improve their overall nutrition, especially those who are malnourished,” said Paul Crispen, M.D., the Cancer Center’s associate director for clinical research and a study adviser.

Mar 27, 2026

3 min

New light-based chip boosts power efficiency of AI tasks 100 fold

A team of engineers has developed a new kind of computer chip that uses light instead of electricity to perform one of the most power-intensive parts of artificial intelligence — image recognition and similar pattern-finding tasks. Using light dramatically cuts the power needed to perform these tasks, with efficiency 10 or even 100 times that of current chips performing the same calculations. Using this approach could help rein in the enormous demand for electricity that is straining power grids and enable higher performance AI models and systems. This machine learning task, called “convolution,” is at the heart of how AI systems process pictures, videos and even language. Convolution operations currently require large amounts of computing resources and time. These new chips, though, use lasers and microscopic lenses fabricated onto circuit boards to perform convolutions with far less power and at faster speeds. In tests, the new chip successfully classified handwritten digits with about 98% accuracy, on par with traditional chips “Performing a key machine learning computation at near zero energy is a leap forward for future AI systems,” said study leader Volker J. Sorger, Ph.D., the Rhines Endowed Professor in Semiconductor Photonics at the University of Florida. “This is critical to keep scaling up AI capabilities in years to come.” “This is the first time anyone has put this type of optical computation on a chip and applied it to an AI neural network,” said Hangbo Yang, Ph.D., a research associate professor in Sorger’s group at UF and co-author of the study. Sorger’s team collaborated with researchers at UF’s Florida Semiconductor Institute, the University of California, Los Angeles and George Washington University on study. The team published their findings, which were supported by the Office of Naval Research, Sept. 8 in the journal Advanced Photonics The prototype chip uses two sets of miniature Fresnel lenses using standard manufacturing processes. These two-dimensional versions of the same lenses found in lighthouses are just a fraction of the width of a human hair. Machine learning data, such as from an image or other pattern-recognition tasks, are converted into laser light on-chip and passed through the lenses. The results are then converted back into a digital signal to complete the AI task. This lens-based convolution system is not only more computationally efficient, but it also reduces the computing time. Using light instead of electricity has other benefits, too. Sorger’s group designed a chip that could use different colored lasers to process multiple data streams in parallel. “We can have multiple wavelengths, or colors, of light passing through the lens at the same time,” Yang said. “That’s a key advantage of photonics.” Chip manufacturers, such as industry leader NVIDIA, already incorporate optical elements into other parts of their AI systems, which could make the addition of convolution lenses more seamless. “In the near future, chip-based optics will become a key part of every AI chip we use daily,” said Sorger, who is also deputy director for strategic initiatives at the Florida Semiconductor Institute. “And optical AI computing is next.”

Mar 26, 2026

3 min

Study: Many pregnant women uncertain of marijuana risks even as use increases

Many pregnant women are unsure if it’s safe to use marijuana or products containing cannabidiol, an active compound in marijuana, even as they increasingly turn to them to combat morning sickness, anxiety or insomnia, a recent University of Florida Health study shows. The American College of Obstetricians and Gynecologists advises against the use of marijuana and cannabidiol, or CBD, during pregnancy. Marijuana use has been associated in some studies with adverse fetal neurodevelopmental outcomes. Evidence of cannabidiol safety is sparse in human studies, but researchers remain concerned that it might nonetheless pose a danger. CBD is not intoxicating. The UF Health researchers said their study shows a need for the medical community to better educate women about the potential hazards to the fetus from using marijuana, also called cannabis. One worry is that some people believe the spreading legalization of marijuana or CBD around the nation equates to the government giving its stamp of approval that the products are safe, researchers said. Medical marijuana is legal in Florida, although its recreational use is not. “If a medication is legal, we assume that maybe it’s safe, although other things like tobacco and alcohol are also legal and we know that those can be harmful to pregnancies,” said Kay Roussos-Ross, M.D., the study’s senior author and a professor in the UF College of Medicine’s Department of Obstetrics and Gynecology. “We see a good deal of data out there that shows that there is increased risk of psychiatric and behavioral issues related to marijuana use in pregnancy, but we need more,” she added. “We need more so that we can be correct in our assessments and our educational efforts to women of reproductive age who are using marijuana.” It’s difficult to quantify the rise of marijuana and CBD use during pregnancy, with most estimates showing an increase predating COVID-19. A 2021 federal survey reported 7.2% of pregnant women used marijuana. The UF Health study noted that emerging evidence from obstetrics care shows more pregnant women are trying the products, perhaps because of increased legalization. The study, published in Medical Cannabis and Cannabinoids, surveyed 261 women and used focus groups to explore participants’ perceptions of the products. The women were either pregnant, breastfeeding or caring for a child 5 years old or younger, and reported use of marijuana or CBD products, such as vapes, smoking, tincture oils or ointments. “There seems to be a disconnect,” said Amie Goodin, Ph.D., an assistant professor in the UF College of Pharmacy’s Department of Pharmaceutical Outcomes and Policy and the study’s lead author. “About one in six pregnant women are telling us, ‘Yes, I have used marijuana or a CBD product while I’m pregnant.’ But half are saying, ‘I don’t know what the risks are.’” About 40% of the pregnant women surveyed said they were unsure how risky it was to use marijuana once or twice a week during pregnancy, compared with 34.5% of women who were not pregnant when surveyed for the study but who had children. Asked the same question about CBD, more than 52% of pregnant women were unsure of the risk, compared with 41.8% for mothers who weren’t pregnant when surveyed. About 36% of pregnant women reported using marijuana, compared with 65% of mothers not currently pregnant, perhaps reflecting at least some increased caution among those in the former group. CBD use was 19.9% for pregnant women and 38.2% for women who were not pregnant. “Some women did mention that the legalization of marijuana has made marijuana more socially acceptable,” said study co-author Deepthi Varma, Ph.D., an assistant professor in the College of Public Health and Health Professions’ Department of Epidemiology. The researchers said they were especially concerned that women were even less sure of the safety of CBD use because it is widely available and often seen as harmless. “You might notice that it’s even something that you can buy at a gas station or a grocery store,” Goodin said. “CBD in a purified form has actually got an FDA approval to treat certain types of pediatric epilepsy on its own … but pharmaceutical-grade CBD is not quite the same thing as you would expect to get if you were purchasing CBD oil at a smoke shop or a gas station.”