The structure of the brain may relatively be responsible for anxiety and negative thoughts in healthy adults, finds a new study from the University of Illinois.
College students who are healthy and have a relatively smaller inferior frontal cortex region were more likely to suffer from anxiety. These people even tend to view negative or positive events in a negative light.
The researchers evaluated 62 students, collecting brain structural data from neuroimaging scans and using standard questionnaires to determine their level of anxiety and predilection for negative bias.
"You would expect these brain changes more in clinical populations where anxiety is very serious, but we are seeing differences even in the brains of healthy young adults," Dolcos said.
The study also found that the relationship between the size of the IFC and a student's negative bias was mediated by their level of anxiety.
"People who have smaller volumes have higher levels of anxiety; people who have larger IFCs tend to have lower levels of anxiety," Dolcos said. And higher anxiety is associated with more negative bias, she said. "How we see this is that the higher volume of the IFC confers resilience."
"We found that larger IFC volume is protecting against negative bias through lower levels of trait anxiety," Hu said.
According to the American College Health Association, anxiety is rampant on college campuses, where nearly 60 percent of students report at least one troubling bout of anxious worry every year.
"There is a very high level of anxiety in the student population, and this is affecting their life, their academic performance, everything," Dolcos said. "We are interested in identifying what is going on and preventing them from moving to the next level and developing clinical anxiety."
Anxiety can interfere with many dimensions of life, causing a person to be on high alert for potential problems even under the best of circumstances, Hu said. Negative bias also can interfere with a person's commitment to activities that might further their life goals, she said.
Understanding the interrelatedness of brain structure, function and personality traits such as anxiety and their behavioral effects such as negative bias will help scientists develop interventions to target specific brain regions in healthy populations, Hu said.
"We hope to be able to train the brain to function better," she said. "That way, we might prevent these at-risk people from moving on to more severe anxiety."