Is amygdala size correlated with stress?

Abstract

Background: One of the important mechanisms that regulate the stress response of the body is hypothalamic pituitary adrenal axis. One of the structures activating this axis is amygdala. We have seen people around who react calmer and cooler to very stressful situations. Are people with smaller amygdala really calmer? Or, can we say that the bigger the amygdala, which is the trigger of the body's response to stress, the more a person panics? Aim of the study is to compare the saliva cortisol levels and amygdala volume.

Materials and methods: Study conducted with 63 male students. Magnetic resonance images of students were taken before their final exam to calculate amygdala volumes. Saliva samples of all students were taken two times to detect cortisol levels in saliva. First one was 20 days before the final exam and second one was on the exam day. We assumed that the students were stressful on exam day.

Results and conclusions: No statistically significant correlation was found between saliva cortisol levels and amygdala volume in the study.

Keywords: amygdala volume; magnetic resonance images; saliva cortisol; stress.