The MHS Journals

Our blog archive of insights and intel


How Does Trauma Affect the Parasympathetic Nervous System?

Mar 2, 2020

What Is the Parasympathetic Nervous System?

The parasympathetic nervous system (PSNS), sometimes called the feed-and-breed or rest-and-digest system, is part of the autonomic nervous system, along with the sympathetic nervous system. Located between the brain and spinal cord, the PSNS is tasked with saving the body’s energy by slowing the heart rate and increasing the activity of the intestines and glands during periods of rest. It also relaxes the sphincter muscles in the gastrointestinal system.

Here are some of the body functions stimulated through the parasympathetic nervous system. The PSNS uses acetylcholine as its primary neurotransmitter, but other peptides may act on the PSNS as well.

  • Sexual arousal
  • Lacrimation (crying or shedding tears)
  • Digestion: The PSNS dilates the blood vessels of the GI system to allow for greater blood flow.
  • Salivation: The PSNS stimulates the salivary glands and speeds up peristalsis.
  • Urination and defecation

The PSNS also constricts air passageways when the body needs less oxygen, such as during rest periods. It also constricts the pupils when closer vision is required. These functions complement those of the sympathetic nervous system, which is best known for stimulating the fight or flight response when the body perceives a threat.


When Is the Parasympathetic Nervous System Activated?

During times of stress, your body’s sympathetic nervous system activates your fight or flight response. It happens quickly so that the body is almost instantly ready to run or defend itself. In contrast, the parasympathetic nervous system’s job is to relax the body and use hormones to slow down those frantic responses once the threat is gone. The PSNS gives the body a calm and relaxed feeling over a period of time. The changes don’t happen as quickly as those of the sympathetic nervous system.


How Does Trauma Affect the Nervous System?

In periods of stress, the body’s fight or flight response activates. A normally regulated nervous system experiences the stress but returns to normal when the threat has passed. This period during which you have the ability to self regulate is called the window of tolerance, and most people move through several of these cycles daily. One example is rushing to get somewhere and running late but relaxing once you reach your destination on time. However, the system works very differently when the body experiences trauma.

Traumatic events push the nervous system outside its ability to regulate itself. For some, the system gets stuck in the “on” position, and the person is overstimulated and unable to calm. Anxiety, anger, restlessness, panic, and hyperactivity can all result when you stay in this ready-to-react mode. This physical state of hyperarousal is stressful for every system in the body. In other people, the nervous system is stuck in the “off” position, resulting in depression, disconnection, fatigue, and lethargy. People can alternate between these highs and lows.

In cases of extreme and chronic stress, such as ongoing trauma, complex PTSD may result. One example is children who are raised in abusive homes. Another is a soldier returning from combat. The nervous system becomes conditioned to exist in a state of fear. That state can continue into adulthood, triggered by things that would seem utterly unrelated to the childhood trauma. For example, the soldier may react to the backfiring of a car as if the sound is gunfire because he or she is in a constant state of fear, ready to react to the firing of a bullet.


How Do You Calm Down the Parasympathetic Nervous System?

A competent and trained therapist can help clients learn to activate the PSNS to control feelings of stress and anxiety, improve mood, boost the immune system, and reduce blood pressure. Many activities can help trigger this calming response in the body:

  • Meditation and progressive relaxation
  • Identifying and focusing on a word that you find peaceful or calming
  • Exercise, yoga, tai chi, and similar activities
  • Spending time in a serene natural place
  • Deep breathing
  • Playing with small children and pets

Other ways to activate the PSNS include getting a massage, repeating a calming chant or prayer, and participating in hobbies. Anything that you find calming, reassuring, and relaxing can be a way to wake up your parasympathetic nervous system.

Some of the techniques to activate the PSNS may come as a surprise. They focus on connecting your brain to the physical activity you are involved in, removing it from the “stuck” stage. Here are some examples:

  • Gently touching your lips with two fingers can activate the PSNS because the lips are rich with parasympathetic fibers.
  • Focusing on one thing at a time and avoiding the temptation to multitask can maximize the benefits of activating the PSNS.
  • Visualization and imagery and picturing yourself in a peaceful place that you love can activate the calming actions of the PSNS.


Self Care and PTSD

Practicing self-care can help those who have PTSD learn to release stress and pull the nervous system back into regulation. These tips can help.

  • Choose relationships that are safe. People who calm you and make you feel secure can help you activate your PSNS. People are social by nature and find comfort in connection with others. Isolation and superficial relationships can even aggravate mental health challenges.
  • Take mindful breaths to connect your breathing to your conscious thoughts rather than to automatic panic responses.
  • Connect with a trauma-focused therapist who understands these concepts and can help you recognize the signs of a dysregulated nervous system. A trained professional can help you identify what’s calming for you, and this may be different from person to person. For example, one person may find it soothing to sit still while others need the motion to feel at peace.


Does DBT Work for PTSD?

Dialectical Behavior Therapy (DBT) is a form of Cognitive Behavioral Therapy (CBT) intended to treat patients with the symptoms of Borderline Personality Disorder (BPD). However, since many of these patients also have Post-Traumatic Stress Disorder (PTSD) and vice versa, DBT can be useful in helping with both diagnoses. BPD and PTSD are both characterized by difficulty in controlling emotions, impulsive behaviors, and problems managing interpersonal relationships.

DBT was developed in the 1980s by Dr. Marsha Linehan. Like CBT, DBT emphasizes controlling thoughts and behaviors in a way that reduces symptoms. However, DBT also focuses on the acceptance of emotions and thoughts through the use of mindfulness skills. Researchers in a German study found that treating people with PTSD using DBT reduced the symptoms, such as depression and anxiety, and led to improvement that continued weeks after the therapy ended. Research continues into this promising use of DBT.


Contact MHS for Help Today

MHS offers DBT for adults and adolescents as young as 12, including those with co-occurring disorders, to help them reduce symptoms and improve quality of life. The Adherent DBT program at the Woodbury, Edina, Plymouth, and Roseville locations is closely modeled after the curriculum developed by Dr. Marsha Linehan. It is nationally accredited and certified by the Minnesota Mental Health Division Department of Human Services.

At MHS, DBT combines different techniques such as mindfulness, emotional regulations, interpersonal skills, and distress tolerance to effect lasting change. Clients identify personal goals, and MHS provides support to help them reach those targets. Therapists help clients get motivated and practice what they learn in therapy.

To learn more about how this intensive outpatient approach can help you, contact us today.

Image Credit: Getty/vadimguzhva