Smells can linger in memory long after the scent fades, shaping mood and behavior. A new study from the University of Florida reveals how the brain assigns emotional value to odors, offering fresh insights for sensory health and potential clinical treatments. The research shows that odor experiences are not just about smell notes—they’re tied to deep brain circuits that determine what we find pleasant or aversive.
In Thailand, where street market aromas swirl and local foods like pla ra (fermented fish) and other pungent scents are integral to daily life, the subjective nature of “good” and “bad” smells is more than a curiosity. As Bangkok and other cities become more diverse, understanding how the brain chooses which odors to embrace could impact mental wellbeing and everyday experiences, including healthcare environments.
The study focused on the amygdala, the brain’s emotional center. Unlike senses that travel through multiple routes, the sense of smell reaches the amygdala directly, enabling odors to rapidly influence emotion. According to the senior author, a professor of pharmacology and therapeutics at the UF College of Medicine, odors can be as powerful as pictures or music in shaping feelings.
Researchers identified two genetically distinct cell types in the brain that help sort smells as positive or negative. Using mice—shown to share important neurochemical traits with humans—the team measured behavior and tracked brain activity. The results showed these cells are flexible: their role depends on their connections and how they communicate with other brain regions. The lead author explained that an odor’s emotional valence can change based on where these cells project in the brain and how they interact with other structures.
This discovery offers hope for people with heightened odor sensitivity. In Thailand, individuals with anxiety, PTSD, autism, or sensory processing challenges sometimes experience distress from everyday smells, including those in clinics or hospitals that trigger distressing memories. The lead author notes that since we constantly breathe, odors continuously shape our experience—and for some, this can be disruptive.
Clinical implications are promising. Thai clinicians and therapists may eventually help patients reframe adverse scent experiences by targeting these neural pathways. For example, students overwhelmed by the fumes of cleaning agents in classrooms or patients deterred from seeking care due to hospital odors could benefit from future interventions.
The research could also pave the way for medications that modulate these brain pathways, reducing distressing emotions tied to smells or restoring pleasant sensations. The senior author emphasizes that emotions greatly influence quality of life and that understanding how surroundings affect feelings can lead to healthier, happier living.
Odor and culture are closely intertwined in Thailand. While durian’s strong aroma delights many locals, others may find it overpowering. This study illustrates how cultural learning and personal experience shape scent judgments alongside biology. The Thai saying “One person’s meat is another’s poison” resonates here, with sense perception adding a new layer to the idea.
Looking ahead, the research invites further exploration across Southeast Asia, where climate, cuisine, and daily routines create a rich tapestry of scent experiences. It also invites inclusive design in public spaces—hospitals, schools, and transit hubs—so people aren’t overwhelmed by environmental odors.
Practical takeaways for Thai readers include creating fragrance-free zones at home and in workplaces, and communicating clearly about air quality in shared spaces to foster inclusion. For educators and business leaders, mindful scent management can support comfort and accessibility. People who experience distress from odors may soon find more options for support, grounded in advances in brain science.
Data from leading neuroscience and health institutions shows how sensory processing shapes daily life. This evolving work points toward tangible improvements in healthcare, education, and everyday wellbeing.