Researchers led by Virginia Tech have discovered how neurotransmitters in the human brain react to the emotional content of language, providing unprecedented insights into how words shape our emotions, decisions and behavior.
In a recent study, an international team of scientists led by Read Montague, a professor at the Fralin Biomedical Research Institute at Virginia Tech, has found that neurotransmitters in the brain are active during the processing of the emotional content of language, providing new insights into how people interpret the significance of words.
Published in Cell Reports, the study explores how brain chemicals, such as dopamine and serotonin, are released when the brain processes emotional words.
“The common belief about brain chemicals, like dopamine and serotonin, is that they send out signals related to the positive or negative value of experiences,” Montague, the co-corresponding and co-senior author of the study, said in a news release. “Our findings suggest that these chemicals are released in specific areas of the brain when we process the emotional meaning of words. More broadly, our research supports the idea that the brain systems that evolved to help us react to good or bad things in our environment might also play a role in how we process words, which are just as important for our survival.”
This innovative research marks the first time scientists have simultaneously measured the release of neurotransmitters, such as dopamine, serotonin and norepinephrine, in the context of human language processing. It enhances our understanding of how language shapes human experiences, emotions and decisions.
The study involved measuring neurochemical activity in patients undergoing deep brain stimulation surgery for conditions like essential tremor and epilepsy, where electrodes were used to monitor brain responses to emotionally charged words.
The researchers observed that various neurotransmitters are released in distinct patterns based on the emotional tone of the words, the brain regions involved and the hemisphere of the brain processing the information.
“The emotional content of words is shared across multiple transmitter systems, but each system fluctuates differently,” Montague added. “There’s no single brain region handling this activity, and it’s not as simple as one chemical representing one emotion.”
The findings were particularly surprising in the thalamus, a brain region not traditionally associated with language or emotional processing.
“This region hasn’t been thought to have a role in processing language or emotional content, yet we saw neurotransmitter changes in response to emotional words. This suggests that even brain regions not typically associated with emotional or linguistic processing might still be privy to that information,” co-corresponding and co-senior author William “Matt” Howe, an assistant professor at Virginia Tech’s School of Neuroscience, said in the news release.
The study’s implications extend beyond humans. Alec Hartle, a doctoral student and co-first author of the study, validated these human findings using optogenetics in rodent models, a technique allowing scientists to control genetically modified cells with light.
“What we observed in the human brain was extraordinary,” Howe added. “The validation in animals supports and solidifies the broader implications of these neurotransmitters in decision-making systems.”
Building on a recent study published in Nature Human Behavior, which highlighted the roles of dopamine and serotonin in social behavior, this research delves into the uniquely human ability to understand and process the emotional content of written words.
“Unlike animals, humans can understand words, their context and meaning,” added first author Seth Batten, a senior research associate in Montague’s lab. “The study examines how neurotransmitter systems process words with different emotional weight, reflecting the hypothesis that these systems, which evolved to keep us alive, now also help interpret language.”
While the study is still in its early stages, its foundational nature opens new avenues for future research into the interplay between language, emotion and brain chemistry.