By Whitney Heins. Photography by Jennie Andrews.
Sahba Seddighi didn’t know a word of English when she left Iran for the United States. But the precocious fourth-grader quickly learned the language and became fascinated with the potential of the human brain.
Now a junior in UT’s College Scholars Program, she is focusing on neuroplasticity—how the brain changes as a result of experience.
Working with Matthew Cooper, associate professor of psychology, Seddighi is putting stress, or specifically what causes it, under the microscope.
“We all respond to stress in different ways. Some get headaches. Some get heart disease. But the underlying mechanisms for the basis of this variation is not fully understood,” Seddighi said.
To help unlock the mystery, Seddighi is using an unusual tool—a community of 100 Syrian hamsters.
Her investigation centers on restricting the playtime of young hamsters to see if a part of their brains called the ventromedial prefrontal cortex (vmPFC) develops differently than more playful subjects. Such a difference could make them more vulnerable to stress later in life, becoming evident through submissive and defensive behavior.
At first, the young hamsters were divided into two groups. One group lived only with their mothers, while the other lived with peers and learned to socialize. Eventually, all hamsters were moved to cages with their peers.
In a rodent version of a reality TV show, the hamsters were then exposed to stressful social situations in which a smaller hamster was put in a cage with a larger aggressive one. Seddighi recorded their activity and counted the frequency and duration of submissive, defensive, aggressive, social, and nonsocial behaviors.
“The hamsters literally fight each other,” Seddighi said. “This social and physical interaction is the basis of psychosocial defeat where a Syrian hamster, known for aggression, loses its aggressive tendency and becomes more vulnerable to stress.”
In the second phase of the study, Seddighi will look at neurons in the hamsters’ brains under a microscope. She will use tracing software to quantify the structure of the neurons, looking at length and junctions—clues to the function and communicative capacity of the nerve cells.
“We expect that mother-housed animals will show altered neural activity in the vmPFC compared to peer-housed animals because of lack of play, making them more vulnerable to stress,” Seddighi said.
If Seddighi’s research supports a link between the vmPFC and stress, better treatment options for stress-related mental illnesses may follow.
“If our hypothesis is proven true, it could lead to novel treatments like using play therapy or drugs that target the underlying biological mechanisms to reduce stress,” she added.
Seddighi has already conducted neuroscience research at the National Institutes of Health and Stanford University. Upon graduation, she plans to enter a doctoral program to explore neurological diseases, with a focus on neuroplasticity as a therapeutic tool.
“We don’t know what causes so many of these often intractable neurological disorders like Alzheimer’s disease and multiple sclerosis,” she said. “I think there is a lot of potential for discoveries that will make a difference.”
While diligently working to uncover the brain’s hidden secrets, Seddighi has developed a profound thirst for research. “To me, it’s the international language of science, a way for the passionately curious to make sense of the world.” Just another language she continues to master on her journey for knowledge.