Your BPD and the Sympathetic Nervous System

When you're in distress, it triggers the fight-or-flight response

stressed business woman
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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 the aforementioned 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, which links your nervous system to your endocrine system, sends adrenaline into your bloodstream. 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, this very well-orchestrated system is more easily triggered, which can cause serious emotional conflict, within and without. 

The Sympathetic Nervous System and Borderline Personality Disorder

Borderline personality disorder (BPD) is a common and disruptive mental illness that affects millions of people within the United States. 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; some studies have found that those with BPD remain in an emotional state 20 percent longer than other people. 

For people with BPD, minor situations which 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 her partner is going to leave her, she may become panicked and distraught, even if her partner has no intention of breaking up with her. Her heart may race, she may cry, and she may feel a rush of adrenaline and take a rash action to prevent her 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, but your family's health history also plays an essential role. 

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Article Sources
  • American Psychiatric Association. Diagnostic and Statistical Manual of Mental Illnesses, 5th edition, 2013. 
  • Austin, M., Riniolo, T., Porges, S. "Borderline Personality Disorder and Emotional Regulation: Insights From the Polyvagal Theory". Brain and Cognition, 2007, 69-76. 
  • Harvard Health Publications. Understanding the Stress Response.  

  • Science Daily. Sympathetic Nervous System