Anxiety can be characterized by feeling out of control, doubting that you are capable of handling situations that might arise, or worrying about the unknown. You might find yourself wondering what your brain is doing while you are experiencing the heightened emotions anxiety tends to bring out. Researchers Burdwood, Infantolino et al. (2016) have been studying how different forms of anxiety are related to different patterns of brain activation. This team began their study by focusing on two general categories of anxiety: anxious apprehension and anxious arousal.
Anxious apprehension is, simply put, a more cognitive form of anxiety. It might entail worrying about the future. It is inward focused and usually involves repetitive thoughts. Those who suffer from anxious apprehension are typically described as frequent worriers, and they tend to be introverted. Anxious arousal pertains more to physical symptoms. These include increased heart rate, and paranoia. If you deal with anxious arousal, you likely feel the need to check over your shoulder, even in a resting state.
Our brains are never really still. FMRI scans provide researchers with maps of brain activity, which proves this to be true. One system of our brain regions is activated when our attention is externally focused, such as when we are working on a project. This is labeled as a Task-Related Network. The Default Mode Network (DMN) is activated when we are not engaging in a specific task, and our attention is inwardly focused.
Burdwood and his colleagues hypothesized that due to anxious apprehension involving an inward focus of your attention, and resting attention is also typically inwardly focused, there must be an increase in activity patterns in the DMN in anxious apprehension. However, they believed that anxious arousal would decrease patterns in the DMN activity.
Volunteers for this experiment were assessed, and then put in groups: control, anxious apprehension, and anxious arousal. While they were in the fMRI scanners, they were asked to complete the color-word and emotion-word Stroop task. Scans were taken during the activity, as well as during the periods of rest.
It turns out, the researchers observed the opposite of what they hypothesized. Anxious apprehension was associated with a decrease in DMN activity, which suggests a decrease in inwardly focused thoughts. This might tell us that those who suffer from anxious apprehension are not feeling introspective or self-referential. Chronic worriers could be engaging in repetitive concern about things that have not happened, instead of concern with the present moment which is usually associated with high levels of DMN activation.
Anxious arousal was shown to be associated with an increase of DMN activity. This could mean that they have a higher level of internal focus of attention, instead of the lower level that was initially expected. It is possible that the focus for the participants during periods of rest was on monitoring their own anxiety. Awareness of your own body requires inwardly directed attention, which could be why the activity patterns in the DMN manifested this way.
There is a debate surrounding whether or not DMN actually shows your resting-state activity in the brain. However, it is suggested that therapy can be extremely helpful for both anxiety and depression. This could be due to the fact that they, in part, alter brain activity in the DMN. If you are struggling with either type of anxiety mentioned above, trying therapy could be a great step for you.
References:
Burdwood, E.N., Infantolino, Z.P., Crocker, L.D., Spielberg, J.M., Banich, M.T., Miller, G.A., and Heller, W. (2016). Resting-State functional connectivity differentiates anxious apprehension and anxious arousal, Psychophysiology, 53(10), 1451-1459. doi:10.1111/psyp.12696.
Blatchley, Barbara. “Anxiety and Your Resting Brain.” Psychology Today, 26 Feb. 2022, https://www.psychologytoday.com/intl/blog/what-are-the-chances/202202/anxiety-and-your-resting-brain.