A groundbreaking study has revealed that scents can fundamentally alter decision-making in mammals by forging indirect associations in the brain—findings that may pave the way for innovative treatments for mental health conditions in humans. The new research, conducted by a multidisciplinary team led by a doctoral student and supervised by a leading neuroscientist, used behavioral experiments in mice to explore how the brain’s response to smells influences future choices—offering important insights for both science and society.
Researchers observed that after mice learned to connect a specific scent—banana—with a pleasant sweet taste, and another scent—almond—with a salty taste, their preferences could be switched by later associating the banana scent with an unpleasant, aversive event. Strikingly, the mice began to avoid the formerly preferred sweet taste whenever it was presented with the banana odor, despite the flavor itself remaining unchanged. This behavioral shift demonstrated the animals’ ability to make decisions based on indirect connections between stimuli: “they formed an indirect association between the sweet taste and the aversive stimulus through its link to a specific smell,” the principal investigator explained (ScienceDaily).
This novel type of learning hinges on so-called “indirect associations,” where the brain links events not directly connected, a cognitive process far more complex than simple classical conditioning. By using genetic techniques and imaging, the research team was able to pinpoint the amygdala—a brain region tied to emotions like fear and anxiety—as a core area activated during the creation of these indirect links between smell and taste. The study also highlighted how the amygdala interacts with the cerebral cortex, forming a newly mapped brain circuit responsible for encoding such sensory associations.
Importantly, when researchers experimentally inhibited the amygdala’s activity, the mice lost the ability to form these pivotal indirect associations. “We have identified a brain circuit that controls associations between stimuli and allows for these indirect associations,” the lead researcher emphasized. This discovery has profound implications for humans, as our brains share similar architecture and decision-making processes with those of mice.
The significance of this finding is particularly relevant for conditions rooted in dysfunctional associations, such as post-traumatic stress disorder (PTSD) and psychosis. In these disorders, parts of the brain—especially the amygdala—react excessively to certain triggers based on learned connections that may no longer be appropriate. According to the researchers, “alterations in these indirect associations form the basis of various mental disorders. Understanding the brain circuits involved in these complex cognitive processes can help us design therapeutic strategies for humans.”
For Thai readers, this research opens new windows into how basic sensory experiences, common and familiar through daily life in Thailand—such as the scent of jasmine from a garland or the aroma of grilled seafood at a night market—could impact mood, behavior, and even mental health. In Thailand, where aromatic practices feature prominently in traditional medicine, religious ceremonies, and everyday cuisine, understanding how olfactory cues influence the brain could inspire new forms of therapy or mindfulness practice. Thai wellness culture already utilizes scents—such as lemongrass, kaffir lime, and camphor—in massage and spa treatments, aligning traditional wisdom with modern neuroscience discoveries.
Furthermore, mental health remains a growing concern in Thailand, particularly as modern urban lifestyles and changing family structures create new stresses. The Ministry of Public Health has noted an increase in diagnosed cases of anxiety and PTSD related to both personal hardship and collective trauma, such as natural disasters or public health crises (Bangkok Post). The new findings support the development of non-invasive, sensory-focused therapies that could be integrated into Thailand’s existing mental health care infrastructure, potentially reducing stigma and broadening access to support services.
This research also underscores the biological importance of the amygdala, a key element in emotional memory and threat perception. In Thai Buddhist teachings, the cultivation of mindfulness—sati—emphasizes awareness of sensory experiences to foster calm and detachment. Understanding the neurobiological roots of such practices might foster new collaborations between modern psychology, neuroscience, and Thai spiritual traditions. Experts from leading mental health institutions point out: “Ancient practices such as aroma meditation or herbal steam therapy may gain new validation as science unravels how scents shape emotions and behavior at a neural level.”
Looking ahead, the research team suggests that their discoveries could lead to brain stimulation or other interventions aimed at modulating amygdala activity in patients suffering from PTSD or psychosis. For Thailand’s health sector, ongoing investment in neuroscientific research and mental health education could position the nation at the forefront of holistic care—bridging global discoveries and deep-rooted local practices.
For Thai families and individuals, practical steps can begin at home or in the workplace: paying attention to the scents in one’s environment, consciously using calming or uplifting aromas, and practicing mindful awareness of how smells evoke emotions and memories. Schools can incorporate odor-based projects in science and mindfulness classes, while clinics could explore integrating aroma-based interventions alongside conventional therapy.
Individuals struggling with strong emotional responses linked to memories might consider consulting mental health professionals who are open to incorporating sensory cues into treatment or self-care routines. As Thailand’s urban environments evolve, designing public spaces and transportation systems with pleasant scents or natural aromatics could also support public wellbeing, as some international airports and hospitals already do.
In summary, this new research demonstrates the remarkable power of scent—not only as a trigger for memories and emotions, but as an architect of the choices we make and the behaviors we adopt. As science begins to decode the neural mechanisms underlying these processes, Thai society has a unique opportunity to combine cultural wisdom with medical innovation for the benefit of all.
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