BPD and the Sympathetic Nervous System

Nervous man giving a speech

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Ever wonder what gets your heart pumping while you're watching a scary movie? Or what's responsible for your quick reaction when someone cuts you off in traffic? Or why your brain goes blank and your palms get sweaty when you have to give a presentation to a room full of people? 

The sympathetic nervous system is what stimulates the "fight-or-flight" response when you're presented with a threat, whether it's being chased by a wild animal or confronting your fear of public speaking. When no threat is present, the parasympathetic nervous system allows your body to rest, recover, and digest nutrients. 

Understanding the Autonomic Nervous System

The sympathetic nervous system is one branch of the autonomic nervous system (the other branch is the parasympathetic nervous system). The autonomic nervous system regulates the functions of organs like your heart, stomach, bladder, and intestines that take place without conscious effort. It also controls the muscles in your body. You usually don't notice this system at work because it acts reflexively in response to stimuli like a wild animal.

In acutely stressful situations, a number of things happen in your brain. First, the amygdala, which is responsible for detecting fear and preparing for emergency events, sends the message to your hypothalamus that you're in danger. In turn, the hypothalamus releases CRH (corticotropin releasing hormone), which stimulates the pituitary to release ACTH (adrenocorticotropic hormone), which then tells the adrenal glands to release adrenaline (epinephrine) and noradrenaline (norepinephrine). This sets off a number of physiological and hormonal changes, such as dilated pupils, increased heart rate and blood pressure, increased alertness, and heightened senses. In addition, blood sugar and fats are released into your bloodstream for energy, so you can "fight" or "flee" from the danger. 

In borderline personality disorder, the very well-orchestrated automatic nervous system is more easily triggered, which can cause serious emotional conflict, both inside and out. 

The Sympathetic Nervous System With Borderline Personality Disorder

Borderline personality disorder (BPD) is a common and disruptive mental illness that affects about 1.4% of the population and 4 million Americans. Despite its prevalence, little research has been performed to study the neurological or physiological mechanisms behind BPD. Some scientists have suggested that better understanding the mechanics behind BPD, such as issues with the sympathetic nervous system, may lead to the creation of more effective treatment options. To date, though some drugs can help manage specific symptoms of BPD, there's no medication specifically approved to treat BPD.

According to the "Diagnostic and Statistical Manual of Mental Illnesses, 5th edition," a reference healthcare professionals review when making a diagnosis, people with BPD typically have trouble regulating their emotions. Researchers have hypothesized that this means the sympathetic nervous system in people with BPD may be overly stimulated, causing intense or irrational reactions. People with BPD tend to display signs of stress longer than others. 

For people with BPD, minor situations that wouldn't impact other people can cause an extreme physical response. This can create extreme stress and anxiety, even if the stress is caused by delusions. For instance, if a person with BPD believes their partner is going to leave them, they may become panicked and distraught, even if their partner has no intention of breaking up with them. Their heart may race, they may cry, and they may feel a rush of adrenaline and take a rash action to prevent their partner from leaving. 

The cause of this heightened response is unknown. Some healthcare professionals believe BPD is caused by a mix of biological and environmental factors, including both genetics and how you were brought up. Abuse, trauma, and abandonment have all been linked to an increased risk of BPD. In one study, 75% of women with BPD had a documented history of childhood sexual abuse. Family history also plays an essential role as BPD is about five times more common among first-degree biological relatives of those with the disorder.

The Importance of Learning to Manage Stress

Whatever the cause, because people with BPD tend to be more readily sent into the fight-or-flight state, and to remain in that state even when the source of stress has ended. Learning to manage the stress that can trigger that spiral is vital to preventing relapses and improving overall health. Over time, maintaining a state of constant alert can cause your body to work overtime. This wear and tear, known as allostatic load, can cause serious health problems.

Of course, having BPD by itself is stressful. Still, there are coping mechanisms that can help you manage your mental health condition. The National Alliance of Mental Illness recommends adopting key strategies such as setting priorities to manage your time, practicing relaxation, exercising regularly, and eating a healthy diet. These strategies may help lessen stress and improve your quality of life.

Press Play for Advice On Regulating Your Emotions

Hosted by Editor-in-Chief and therapist Amy Morin, LCSW, this episode of The Verywell Mind Podcast shares how to deal with your emotions in any circumstance that may come your way. Click below to listen now.

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5 Sources
Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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  5. National Alliance on Mental Health. Managing Stress.

Additional Reading

By Kristalyn Salters-Pedneault, PhD
 Kristalyn Salters-Pedneault, PhD, is a clinical psychologist and associate professor of psychology at Eastern Connecticut State University.