Stressed out? Blame your amygdalae

Clipart: Royalty free from http://www.cliparthut.com. Text: Neuronicus.

Sooner or later, everyone is exposed to high amounts of stress, whether it is in the form losing someone dear, financial insecurity, or health problems and so on. Most of us manage to bounce right up and continue with our lives, but there is a considerable segment of the population who do not and develop all sorts of problems, from autoimmune disorders to severe depression and anxiety. What makes those people more susceptible to stress? And, more importantly, can we do something about it (yeah, besides making the world a less stressful place)?

Swartz et al. (2015) scanned the brain of 753 healthy young adults (18-22 yrs) while performing a widely used paradigm that elicits amygdalar activation (brain structure, see pic): the subjects had to match a face appearing in the upper part of the screen with one of the faces in the lower part of the screen. The faces looked fearful, angry, surprised, or neutral and amygdalae are robustly activated when matching the fearful face. Then the authors had the participants fill out questionnaires regarding their life events and perceived stress level every 3 months over a period of 2 years (they say 4 years everywhere else in the paper minus Methods & Results, which are the sections that count if one wants to replicate; maybe this is only half of the study and they intend to follow-up to 4 years?).

The higher your baseline amygdalar activation, the higher the risk to develop anxiety disorders later on if expossed to life stressors. Yellow = amygdala. Photo credit: https://www.youtube.com/watch?v=JD44PbAOTy8, presumably copyrighted to Duke University.

The finding of the study is this: baseline amygdalar activation can predict who will develop anxiety later on. In other words, if your natural, healthy, non-stressed self has a an overactive amygdala, you will develop some anxiety disorder later on if exposed to stressors (and who isn’t?). The good news is that knowing this, the owner of the super-sensitive amygdalae, even if s/he may not be able to protect her/himself from stressors, at least can engage in some preventative therapy or counseling to be better equipped with adaptive coping mechanisms when the bad things come. Probably we could all benefit from being “better equipped with adaptive coping mechanisms”, feisty amygdalae or not. Oh, well…

Reference: Swartz, J.R., Knodt, A.R., Radtke, S.R., & Hariri, A.R. (2015). A neural biomarker of psychological vulnerability to future life stress. Neuron, 85, 505-511. doi: 10.1016/j.neuron.2014.12.055. Article | PDF | Video

By Neuronicus, 12 October 2015