J.R.R. Tolkien, creator of brave hobbits Frodo Baggins and Samwise Gamgee, writes that “courage is found in unlikely places.” While Tolkien is hinting at an allegorical pool of strength within us, scientists have actually pinpointed where a certain kind of courage is physically found: the brain.
In a study released Friday in Nature Communications researchers from Sweden’s Uppsala University and Brazil’s Federal University of Rio Grande reveal that a group of cells buried in the hippocampus play a key role in our decision to flee or face our fears.
The cells are called oriens-lacunosum moleculare (OLM) interneurons and in the paper, the scientists explain that manipulating these cells can affect how anxious a person is or how willing one is willing to take a risk.
The discovery of what role these neurons play in the brain illuminates what underlies the cognitive and emotional processes behind bravery and hints at a new pathway that scientists can target to treat anxiety, says study co-author and post doctoral researcher Sanja Mikulovic, Ph.D..
“OLM cells appear to produce synchronicity between brain regions that control anxiety, or at least minimize it,” Mikulovic tells Inverse.
When asked if OLM cell manipulation could hypothetically make a person braver, anxiety or not, Mikulovic says, “we believe that it could be done.”
Bravely Smelling Cat Hair
When a mouse is waiting in its hole as a cat walks by — feeling safe while in a threatening environment — its hippocampus produces pulsating rhythms called theta oscillations. There are two types of theta oscillations: the first drives exploration and voluntary movement, and the second is linked to emotional states such as anxiety, and the sense that a predator is near.
In this study, scientists took genetically engineered mice and studied their brains as they responded to predator threats, like the smell of cat hair. When they stimulated the OLM cell group, the mice were more comfortable taking risks. When this cell group was inhibited, the risk-taking behavior stopped.
Overall, they found that stimulated OLM cells generated theta oscillations that made the mice sense danger but still feel secure. In other words, the mice felt braver.
“[The OLM cells] activation drives a brain activity that causes mice to not fear the predator,” explains Mikulovic. “This activity exists in parallel with ‘cognitive’ brain activity that allows mice to, for example, find their way in the environment. It is fascinating how the brain ‘tells’ us, in the form of this activity, that both emotion and cognition are interaction, in order to make the decision necessary for survival.”
How This Research Could Be Used to Help People
The finding indicates that OLM cells trigger risk-taking behavior, and it could be something scientists target when treating pathological anxiety.
People with high anxiety levels are less likely to take risks, after all, and researchers think developing antidepressants designed to affect these cells can result in more efficient anxiety treatments. This same research team also determined that OLM cells are very sensitive to nicotine — indicating that OLM cells could also explain why people binge smoke when they’re anxious.
Whether you’re a hobbit approaching Mount Doom or a mouse sniffing cat hair, or person living with pathological anxiety, creating more theta oscillations in your hippocampus might be the help needed to be braver.