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Its initial use was for epilepsy in the late 1990’s, via an implantable device in the neck. Since then, “vagus nerve stimulation” (VNS) has shown much wider therapeutic promise, including as a non-invasive treatment for PTSD, depression, and substance addiction. That is why FHE Health, in its mission to revolutionize behavioral healthcare, is now one of a small number of providers nationwide to offer VNS.
For help demystifying VNS, the science behind it, and its application for psychiatric disorders, we reached out to a member of our neuro team who administers VNS. Dr. Bishop is a licensed clinical psychologist. She has more than 15 years of experience in the field of neurotherapy and, in research currently underway at FHE, is helping to collect data regarding patient outcomes with VNS.
In the Q&A below, you’ll hear from Dr. Bishop in her own words about what VNS is, how it works, when it can be beneficial, the research that supports its use, and other key information.
Vagus Nerve Stimulation: What It Is and How It Works
Q: What is VNS and how does it work?
A: Vagus nerve stimulation is a form of neuromodulation that stimulates the vagus nerve. Vagus nerve stimulation is sometimes thought of as a “pacemaker for the brain.” It has historically been used as a treatment for epilepsy, as well as treatment-resistant depression.
More recently, VNS is showing a lot of potential as a safe treatment for a variety of neuropsychiatric conditions. It delivers electricity to the vagus nerve, which activates the parasympathetic response (the body’s own natural, self-calming mechanism) and reduces heart rate. The vagus nerve is the main component of the parasympathetic nervous system, which oversees a lot of regulatory body functions like heart rate, mood, and digestion. The vagus nerve connects the gut with the brain. Modulating the vagus nerve often has a therapeutic effect, in part due to its relaxing and anti-inflammatory properties.
Q: How is VNS different from other forms of neurostimulation?
A: It is just another tool in the bag. It uses the same techniques but is applied via an ear clip to the left tragus (the outer ear’s tongue-like tab) as a stimulation site for the vagus nerve.
Q: How is VNS at FHE Health different from VNS implants that treat epilepsy and treatment-resistant depression?
A: VNS implants are associated with continuous on-off stimulation. They also require surgical implantation, which may not be ideal for many people.
Infection is always a risk with any implant. Other side effects associated with VNS implants can include bradycardia, weakness of the vocal cords, alterations in voice, cough, and headache.
The vagus nerve stimulation here at FHE health does not require surgery and improves the safety and tolerability of vagus nerve stimulation. To date, there have been zero significant adverse effects with vagus nerve stimulation. The VNS here at FHE health is done in combination with other neurostimulation methods that encompass cutting-edge techniques and advances in the science.
What Vagus Nerve Stimulation Treats
Q: What conditions does VNS treat?
A: VNS was approved by the FDA in 1997 for treatment in some epilepsy conditions, and in 2005 for the treatment of recurring depression. Currently, there is significant research being done regarding use of VNS for GI conditions, addictions/substance misuse, and other psychiatric conditions, particularly PTSD.
Vagus Nerve Stimulation for “Dorsal Freeze” and Hypervigilance in PTSD
Q: Can you talk about how VNS reduces symptoms of PTSD?
A: Commonly, chronic stress and unresolved trauma disturb the balance between the sympathetic and parasympathetic functions of the nervous system. We also live in a world in which our sympathetic nervous system is often activated or overstimulated, so we need access to tools that help us stimulate the parasympathetic nervous system daily.
The vagus nerve has an inhibitory influence upon the sympathetic nervous system activity. In our day-to-day experiences, our brains are often involuntarily scanning situations and people to determine if they are safe or dangerous—this is part of our autonomic nervous system and happens often without us being aware of it. The vagus nerve plays a large part of this scanning process.
There are two sides to a vagus nerve, ventral (front, anterior), and dorsal (back, posterior). The ventral side responds to safety cues. The dorsal side responds to danger cues—it pulls us into a state of self-protection.
In moments where we experience an extreme danger cue, we can shut down and feel frozen. That is an indication that our dorsal vagal nerve has taken over. For those who have experienced trauma, a danger cue can move them straight into dorsal freeze.
Exercises to calm the vagus nerve can help us reset or bring us out of dorsal freeze. When we stimulate the vagus nerve, we can help the system to regulate itself and combat the freeze state, helping the system to reset after a stress response and restoring the body to a regulated state.
The Neurobiological Effects of VNS
Q: How does VNS help the brain to better self-regulate? In other words, what is going on in the brain at a neurobiological level during VNS?
A: The vagus nerve is the key player in the parasympathetic nervous system. Neurobiologically, vagus nerve stimulation inhibits inflammation, the stress response, and sympathetic (“fight or flight”) activity. It increases blood flow to the brain (thus increasing resources and nutrients the brain needs to heal). It is thought to increase the level of many different neurotransmitters. It also activates part of the prefrontal cortex, which helps to regulate the brain’s limbic system (controlling emotion).
Who Can Benefit from VNS and How to Know
Q: How do you determine whether someone could benefit from VNS?
A: If a person reports ongoing depression and/or PTSD, they may benefit from vagus nerve stimulation. During the assessment process, a person undergoes a QEEG, which incorporates heart rate monitoring as well. (A QEEG is a computer-generated analysis of the brain’s electrical activity. Heart rate monitoring gauges the time intervals between heartbeats.)
Low heart rate variability can increase one’s vulnerability to stress and is associated with increased emotional dysregulation. The vagus nerve supports the communication between the heart and the brain. Heart rate variability can also serve as an indicator of physiological stress or anxiety. Higher heart rate variability indicates greater flexibility and adaptability of the autonomic nervous system in general.
Many individuals can benefit from VNS, including those with anxiety and mood-related disorders, and particularly those with problematic heart rate variability.
The Future Application of VNS for Psychiatric Disorders?
When asked to speculate about the future of VNS for people with psychiatric disorders, Dr. Bishop cited a “huge study (known as the RECOVER study) on the effectiveness of VNS with treatment-resistant depression.” She said that “it is a commonly held belief that results of the RECOVER study may lead to greater insurance coverage for VNS.”
In other words, greater, more affordable access to VNS could be a much-needed breakthrough for millions of people.
Interested in vagus nerve stimulation for you or a loved one? Contact FHE Health today for more information.
