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The Limbic System: A Little-Known System That Can Cause Huge Dysfunction

Jonathan Vellinga, MD


The limbic system is not something that is often discussed, nor is it as widely known as other systems in the body. However, this small but important set of structures in the brain are in charge of many of the body’s most basic and high-level functions. Unfortunately, when it is not working properly symptoms may arise that are varied, widespread, intense, and quite confusing. It takes a trained eye to be able to see the effects of an over- or under-active limbic system, and functional medicine is leading the way in recognizing, treating, and healing limbic dysfunction.


The Limbic System: A Little-Known System That Can Cause Huge Dysfunction


What are the limbic system structures, and what does this system do?


The limbic system is located in the brain, including much of the inner, middle part of the brain just above the brainstem (1). Because knowledge of this system is rather new, there is some debate about which parts of the brain are included, but the hippocampus and amygdala are the most widely agreed-upon with other areas of the brain undoubtedly involved as well (2). The included structures support a range of functions, including (1, 2, 3):

  • Evaluating and processing emotion, as well as emotional reactivity and response

  • Determining threats and preparing the body for the fight or flight response

  • Sexuality

  • Learning

  • Memory consolidation and recall, especially about emotions

  • Emotional reaction to pain

  • Regulating aggressive and combative behavior

  • Sense of smell

  • Some motor behavior (including voluntary and involuntary movement)

Because the limbic system supports so many key functions that humans need to survive (emotion, behavior, learning, and long-term memory), the limbic system is also called the emotional nervous system (1). It is also a possible explanation for the link between emotions and physical responses, e.g. how stress can lead to hypertension or emotional distress to digestive upset (1).


What happens when the limbic system is dysfunctional?


Limbic system dysfunction can affect all of the processes listed above, which can have incredibly far-reaching consequences. Dysfunction, whether from genetics, trauma (physical or emotional), underlying health issues, toxicity, illness, inflammation, or other physical factors, can cause a number of symptoms, including (1, 2, 3, 4, 5, 6):

  • Strong reactions to mild stimuli from sounds, light, fragrance, touch, stress, etc.

  • Chronic pain

  • Various digestive issues

  • Mast cell activation

  • Low energy, chronic fatigue

  • Anxiety, fear, and anxiety disorders

  • Low motivation, depression

  • PTSD

  • Brain fog, disorientation, memory loss, and disorders such as dementia or Alzheimer’s

  • Changes in behavior, such as disinhibited behavior, increased anger or violence, or changes in mood

  • Over-, binge-, or emotional eating, as well as other forms of appetite dysregulation

  • Substance abuse or dependence

  • Changes to sex drive

  • Seizures, epilepsy, or movement disorders


The Problem with Limbic System Dysfunction


Because the extent of damage and dysfunctions of the limbic system are still being discovered and studied (and even the structures that make up the system are still yet to be agreed upon!), it often goes underdiagnosed. However, underdiagnosis is not only attributed to its novelty. It can be difficult for practitioners to determine the root cause of symptoms given that limbic system dysfunction can result in such a wide range of symptoms, and so can present as any number of combinations of physical, psychiatric, cognitive, and/or behavioral symptoms (6). Patients are often offered a number of other treatments to help the wide-ranging symptoms, while the root of the issue goes untreated. This is so unfortunate, because so often limbic system dysfunction is able to be treated (6)!


Limbic System Retraining Programs


In order to treat any dysfunction, especially one involving the brain, it is critical that the patient and their physician work together to compile as much information as possible. The physician will take a full health history including any injuries, illnesses, and family history, as well as past travel, and will likely perform tests that may cover a variety of functions. Once it is determined that the symptoms are not arising from other sources and that it could be limbic system dysfunction, then treatment will move forward.


Functional medicine’s primary focus is on treating the root cause, while simultaneously alleviating symptoms in order to give the body as much relief and energy toward healing as possible. Limbic system retraining programs are some of the most effective treatment options available, combining a number of different mindfulness and therapy-based approaches which help to improve brain plasticity and allow it to respond differently to stimuli. Not only will we work with you to find the right program to help treat your limbic system, but our team will also work with you to find the right supportive lifestyle to help ensure its effectiveness.


Dynamic Neural Retraining System (DNRS)


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