When Stress Speaks Through the Body: The Nervous System, Somatic Symptoms, and What We May Not Yet Know We Are Carrying

Stress is often described as an emotional or mental experience: worry, pressure, overthinking, irritability, or overwhelm. Yet stress is not only psychological. It is also physiological. When the brain and body perceive threat, uncertainty, conflict, pain, or prolonged demand, the nervous system mobilizes. Heart rate, breathing, muscle tension, digestion, pain sensitivity, and blood pressure can all be affected by the body’s stress response (American Psychological Association, 2018; Yaribeygi et al., 2017).

This is why stress may not always appear as “I feel stressed.” Sometimes it appears as a clenched jaw, tight shoulders, stomach discomfort, headaches, dizziness, chest tightness, exhaustion, nerve-like pain, or a sudden sense that the body can no longer continue performing calm. The body may register strain before the person consciously recognizes that they are overwhelmed.

The stress response involves several interacting systems, especially the autonomic nervous system and the hypothalamic-pituitary-adrenal axis, often called the HPA axis. The autonomic nervous system regulates involuntary bodily functions such as heart rate, blood pressure, breathing, and digestion. Under stress, the sympathetic branch of this system prepares the body for action: the heart may beat faster, muscles may tense, breathing may become shallow, and the body may become more alert (Chu et al., 2024; Yaribeygi et al., 2017). The HPA axis is involved in the hormonal stress response, including cortisol release, which helps the body respond to challenge but may become dysregulated when stress is chronic or repeatedly activated (Herman et al., 2016).

This does not mean physical symptoms are “all in your head.” That phrase is both clinically inaccurate and dismissive. A more scientifically accurate statement is that the mind and body are deeply connected through the nervous system, endocrine system, immune system, and pain-processing pathways. Stress can influence inflammation, immune functioning, cardiovascular activity, sleep, gastrointestinal activity, and sensitivity to pain (American Psychological Association, 2018; Yaribeygi et al., 2017). The body is not pretending. The body is responding.

This distinction is especially important when discussing pain. Pain and stress can reinforce one another. Pain is stressful, and stress can make pain feel more intense. Research on chronic pain suggests that stress can influence pain sensitivity, threat perception, avoidance behaviors, and nervous system reactivity (Timmers et al., 2019). In some pain conditions, the nervous system may become more sensitive over time, a process often discussed in relation to central sensitization, in which the brain and spinal cord become more responsive to pain signals (Mohabbat et al., 2023; Nijs et al., 2023).

This may help explain why symptoms such as nerve pain, back pain, headaches, muscle tension, or pain from an existing medical condition can feel worse during periods of emotional overload. Stress may not be the original cause of a pinched nerve, migraine pattern, injury, or chronic pain condition. However, stress can become part of the maintenance cycle by increasing muscle tension, disrupting sleep, intensifying pain sensitivity, and keeping the nervous system in a state of heightened alertness (Timmers et al., 2019; Yaribeygi et al., 2017).

Fainting or near-fainting can also involve the nervous system. Vasovagal syncope, sometimes called reflex syncope or neurally mediated syncope, occurs when the autonomic nervous system overreacts in a way that can lower heart rate and blood pressure, reducing blood flow to the brain and causing fainting or presyncope (Arcinas et al., 2024; Jeanmonod et al., 2023). It can be triggered by factors such as pain, prolonged standing, heat, medical procedures, fear, or emotional stress (Jeanmonod et al., 2023). This does not mean every fainting episode is psychological. Syncope should always be medically evaluated. But it does show that emotional and physiological states can meet in the body in very concrete ways.

Somatic symptoms are another area where the mind-body relationship becomes clinically important. Somatic symptoms are physical symptoms that may be influenced, intensified, or maintained by psychological and physiological stress processes. They may include pain, fatigue, dizziness, gastrointestinal symptoms, shortness of breath, or other bodily sensations. Contemporary research on somatic symptom presentations emphasizes that these experiences are real and distressing, whether or not they are fully explained by a medical condition (Mewes, 2022; Smakowski et al., 2024). The clinical question is not whether the symptom is “real.” The clinical question is how the person’s body, nervous system, emotional life, and environment are interacting.

From a psychodynamic perspective, the body can also become a place where unrecognized emotional conflict is expressed. This does not mean symptoms have a simple symbolic meaning. It would be clinically careless to say, “Your neck pain means anger” or “Your fainting means fear.” Human bodies are far more complex than that. But it may be meaningful to ask what the body has been carrying, especially when someone has learned to override their needs, minimize their emotions, stay productive under pressure, or remain composed in situations that are internally overwhelming.

Many people do not realize how much stress they are holding because stress has become familiar. They may function well, meet responsibilities, care for others, perform competence, and keep moving forward. Yet functioning is not the same as regulation. A person can appear calm while their nervous system remains activated. A person can be productive while their body is tense, exhausted, inflamed, or bracing.

This is where therapy can offer a more nuanced form of attention. Therapy does not replace medical care, and physical symptoms should be assessed by appropriate medical providers. However, therapy can help a person become more curious about patterns: When do symptoms flare? What was happening emotionally before the body reacted? What kinds of conflicts, relationships, responsibilities, or internal pressures tend to precede pain, dizziness, fatigue, or shutdown? What feelings are difficult to recognize until they become physical?

Talk therapy helps because language can organize experience. When a person begins to put words to what has been held in the body, they may start to notice connections between stress, emotion, memory, relationship patterns, and physical symptoms. This does not mean talking immediately removes pain or bodily distress. Rather, therapy can help bring unconscious or minimized experiences into awareness, reduce the isolation around symptoms, support emotional regulation, and create more choice in how a person responds to internal strain.

In a psychodynamic and integrative therapy process, the body is not treated as separate from the person’s story. Symptoms are approached carefully, not as evidence that something is “imaginary,” but as part of a larger clinical picture. The therapeutic relationship can help a person slow down, listen to their body without fear or judgment, and explore what their nervous system may have been carrying for too long.

A clinically mature approach holds two truths at once: physical symptoms deserve medical attention, and they may also deserve psychological understanding. The body is not separate from the story. The nervous system develops in relationship, adapts to stress, learns from threat, and responds to meanings we may not yet have language for.

Stress does not always announce itself as stress. Sometimes it speaks through the body first. Sometimes the body knows we are overwhelmed before we do.

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References

American Psychological Association. (2018). Stress effects on the body. American Psychological Association. https://www.apa.org/topics/stress/body

Arcinas, L. A., Iskander, B., & Lerman, B. B. (2024). The role of the autonomic nervous system in vasovagal syncope. Journal of Clinical Medicine, 13(13), 3746. https://doi.org/10.3390/jcm13133746

Chu, B., Marwaha, K., Sanvictores, T., & Ayers, D. (2024). Physiology, stress reaction. In StatPearls. StatPearls Publishing.

Herman, J. P., McKlveen, J. M., Ghosal, S., Kopp, B., Wulsin, A., Makinson, R., Scheimann, J., & Myers, B. (2016). Regulation of the hypothalamic-pituitary-adrenocortical stress response. Comprehensive Physiology, 6(2), 603–621. https://doi.org/10.1002/cphy.c150015

Jeanmonod, R., Sahni, D., & Silberman, M. (2023). Vasovagal episode. In StatPearls. StatPearls Publishing.

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Mohabbat, A. B., Mahapatra, S., & Jenkins, S. M. (2023). Central sensitization: When it is not “all in your head.” American Family Physician, 107(1), 86–87.

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Smakowski, A., Hüsing, P., Löwe, B., & Toussaint, A. (2024). Psychological risk factors of somatic symptom disorder and bodily distress disorder: A systematic review and meta-analysis. Journal of Psychosomatic Research, 180, 111683. https://doi.org/10.1016/j.jpsychores.2024.111683

Timmers, I., Quaedflieg, C. W. E. M., Hsu, C., Heathcote, L. C., Rovnaghi, C. R., & Simons, L. E. (2019). The interaction between stress and chronic pain through the lens of threat learning. Neuroscience & Biobehavioral Reviews, 107, 641–655. https://doi.org/10.1016/j.neubiorev.2019.10.007

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