Amygdala Response During Anticipatory Anxiety in Patients with Tension-type Headache

Tension-type headache (TTH) is the most prevalent primary headache disorder, affecting 0.5%〜4.8% of the population worldwide. Psychological factors play an important role in the pathogenesis of TTH. For instance, depression and anxiety are thought to enhance central sensitization, and thus increase the frequency of headaches. In this study, we used the Minnesota Multiphasic Personality Inventory (MMPI) and measures of anxiety to analyze personality traits associated with TTH. Specifically, we were interested in the relationship between these variables, respiratory responses, and brain activity. Our results showed that individuals with TTH had significantly higher state anxiety scores compared with healthy controls. In addition, individuals with TTH showed a greater increase in RR during a stressful task involving anticipation of an electrical stimulation. During anticipatory anxiety, there was bilateral amygdala (AMG) activation in TTH patients, while only the right AMG was activated in healthy controls. Interestingly, patients in the TTH group with high levels of state anxiety and high scores on schizophrenia scales had the following MMPI personality traits: peculiar perception, poor familial relationship, difficulties concentrating, and lack of deep interest. We suggest that the psychological factors associated with the above-mentioned brain activation might induce peripheral muscle pressure, which then triggers headaches