Neuroscience of Overthinking and rumination: What goes on inside our brain

Published by Aaradhana Reddy

Counselling Psychologist (M.Sc Counselling Psychology)

To holistically understand any psychological phenomenon, we have to understand three important aspects. All these aspects together influence our personality, how we think, behave and express our emotions.

 a. Biological: Biological aspects involve genetics, neurotransmitters and brain structures.

b. Psychological: Psychological aspects involve our personality, how we react and respond to events and situations around us. Importantly it also involves how we feel, our mood and how we express our emotions.

c. Social: Social factors involve our culture. It involves our family, religion, upbringing etc. It includes the values, morals, ideals etc. It polices how we behave, think and express our emotions.

In psychology, we call it the biopsychosocial model. It use it to holistically understand the concern from all three aspects. We see the interactions between them, to understand the root causes and the maintaining factors. In this article, we will see the biological aspect of overthinking and rumination, we will see the neuroscience behind them. To under the social and psychological aspects of overthinking and rumination, you check our blog post about causes, types and coping methods.         

Neuroscience of overthinking and rumination

Various networks in our brain are involved in rumination. Rumination is strongly linked to a network in our brain called the Default Mode Network (DMN). This network consists of 

• medial prefrontal cortex (PFC)

• ventral anterior cingulate cortex (ACC)

• precuneus

• posterior cingulate cortex (PCC)

• bilateral angular gyri (Lois & Wessa, 2016).

The Default Mode Network and the Dorsal Attention Network

The DMN is network of regions in the brain that are involved in self-reflective thought, introspection, day dreaming, recollecting past etc. Ideally DMN is active in times of rest and deactivates when running out a task such as when a person is working. During a task, the brain shifts from the DMN to the Dorsal Attention Network (DAN). DAN helps in focusing/maintaining attention on a task and goal directed action. DAN becomes inactive in times of rest. The above is the ideal functioning of DMN and DAN.

But in case of rumination, DMN is overactive and DAN remains inactive even when necessary tasks and goals must be done or carried out by the person. To put it in simpler terms, during overthinking and rumination, it becomes difficult for the individual to take any decision or action to solve a problem due to overactive DMN and inactive DAN. Hyperactive DMN causes excessive worry, anxiety and low emotional regulation, which makes it difficult to switch to cognitive control networks like DAN and other systems in the brain that could help with problem solving, emotional regulation etc. While this switch would be easier for an individual who does not overthink or ruminate; it might feel next to impossible for an individual who does. “Taken together, functional interactions between DMN and cognitive control networks (DAN and others) may play an important role in rumination” (Lois & Wessa, 2016, p. 1793). Hyperactivity in DMN especially in its core structures (mPFC and PCC) is linked to brooding negative self-referential thoughts. See types of rumination.  

Subgenual Prefrontal Cortex and the limbic system

Another area in the brain that is linked to rumination and DMN is the subgenual prefrontal cortex (sgPFC). It is located under the corpus callosum and is very important for emotional regulation, mood, self-referential thoughts etc. Since sgPFC is involved in emotional processing, regulation and self-referential thinking, excessive activity in this region is associated with self-referential rumination (Bratman, Hamilton, Hahn, Daily, & Gross, 2015). Studies have also shown that functional connectivity (communication between different brain structures) between DMN and sgPFC predicted rumination. Meta-analysis of depressive rumination found that the extent of individual rumination can be predicted by the functional connectivity of the sgPFC and DMN (Gao, Yan, & Yuan, 2022; Hamilton, Farmer, Fogelman, & Gotlib, 2015). Increased connectivity between these two areas can lead to a vicious cycle of rumination.

            Subgenual prefrontal cortex is also an important part of the limbic system. Limbic system consisting of hypothalamus, amygdala, hippocampus and others plays a major role in emotional processing, regulation, emotional memories etc. In times of stress or trauma, an overactivated amygdala leads to something called an amygdala hijack, characterized by intense emotional outbursts either rage or panic triggering fight or flight response which often bypass the rational centers of our brain (rational processing is dampened hence the name hijack) leading irrational and extreme reactions. Something very similar happens during rumination where cognitive control centers (DAN) remain deactivated. These two amygdala hijack and rumination often complement and sustain each other. Rumination can keep the amygdala overactive possibly triggering a hijack. “Trait rumination factors were significantly positively associated with increased sustained amygdala reactivity” (Mandell, Siegle, Shutt, Feldmiller, & Thase, 2014, p. 47). Hence, the individual is caught in vicious cycle, since both rumination and overactive amygdala is involuntary and difficult to get out of; sustaining the cycle.

When to seek professional help?

If overthinking and rumination has become intrusive and they are affecting your daily routines, your work/education spaces and your relationships and social life, it is important that you seek professional help. Additionally, overthinking and rumination is also starting to affect your mood, it is a sign that you need to start trying to manage them. In my counselling practice, overthinking and rumination is a common occurrence and a risk factor in anxiety and depression.

To know more about our approach to anxiety and depression, you can check our services page.

Overthinking and rumination can be very distressing and may feel difficult to get out of; but with practice it can be managed. At Safe Space Counselling, we believe in holding empathic and safe places for emotional expression and then focus on mindfulness based Cognitive Behavior Therapy for overthinking and rumination. This helps individuals to get to root causes and deal with them effectively.

To learn more about our approach to overthinking and rumination, you can visit our services page.

You can also reach out to us for any further questions or chat with us.

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About

Aaradhana Reddy is a Counselling Psychologist with over 8 years of experience with both adolescents and adults. She specializes in adolescent mental health concerns and in dealing with various mental health disorders and other psychological concerns. She is a trained and experienced Cognitive Behavior Therapist and a passionate writer about mental health and well-being. She aims to raise awareness on mental health through her practice and blog.

References

Bratman, G. N., Hamilton, J. P., Hahn, K. S., Daily, G. C., & Gross, J. J. (2015). Nature experience reduces rumination and subgenual prefrontal cortex activation. Proc Natl Acad Sci U S A, 8567-8572.

Gao, W., Yan, X., & Yuan, J. (2022). Neural correlations between cognitive deficits and emotion regulation strategies: understanding emotion dysregulation in depression from the perspective of cognitive control and cognitive biases. Psychoradiology, 86–99.

Hamilton, J. P., Farmer, M., Fogelman, P., & Gotlib, I. H. (2015). Depressive Rumination, the Default-Mode Network, and the Dark Matter of Clinical Neuroscience. Biol Psychiatry, 224-230.

Lois, G., & Wessa, M. (2016). Differential association of default mode network connectivity and rumination in healthy individuals and remitted MDD patients. Soc Cogn Affect Neurosci. , 1792–1801.

Mandell, D., Siegle, G., Shutt, L., Feldmiller, J., & Thase, M. E. (2014). Neural substrates of trait ruminations in depression. J Abnorm Psychol. , 35-48.