The Limbic System

limbic-system

Located in the center of both hemispheres of the brain just under the cerebrum, the limbic system includes the amygdala, hippocampus, hypothalamus, olfactory cortex, and thalamus. The limbic system is a busy part of the brain, responsible for regulating both our emotional lives and higher mental functions such as learning, motivation, formulating and storing memories, controlling adrenaline and autonomic response, and regulating hormones and sexual response, sensory perception (optical and olfactory), and motor function.

Since the limbic system is involved in so many of the body’s activities, and because it works so closely with several other systems, the actual anatomical parts of the limbic system are somewhat controversial. It is the reason there is pleasure in activities such as eating and sexual intimacy, and why stress manifests in the physical body and directly impacts health.

The limbic system is directly responsible for the processes of intercellular communication that affect how an individual responds to situations and all sensory stimuli and forms and stores memories about those situations and the resulting emotions. The limbic system works closely with the endocrine system to help with hormone regulation. It partners with the autonomic nervous system the part of the body responsible for the “fight-or-flight” response, that helps the body recuperate during periods of rest, that regulates heart rate and body temperature, and that controls gastrointestinal functions. It also works with the nucleus accumbens, the pleasure center of the brain which is involved with sexual arousal and euphoric response to recreational drugs.

Deep in the core of the limbic system lies the amygdala, which is involved in many of the limbic activities listed above. it serves a the “watchtower,” evaluating situations to help the brain recognize potential threats and prepare for fight-or-flight reactions. One of the ways it performs its duties is through the sense of smell. Aromas, via the olfactory system, have a quick, unfiltered route to the amygdala where emotions and memories are stored. Why? Because the sense of smell is necessary for survival.

The sense of smell is one of the more complex and discerning senses and is ten thousand times more powerful than our sense of taste. It was not until the early 1990s that biologists first described the inner workings of olfactory receptors — the chemical sensors in our noses — in a discovery that won a Nobel Prize. Since then, the plot has thickened. Over the last decade or so, scientists have discovered that odor receptors are not solely confined to the nose, but found throughout body — in the liver, the heart, the kidneys, skin and even sperm — where they play a pivotal role in a host of physiological functions.

Aromas have a direct and profound effect on the deepest levels of the body systems, emotions, and psyche. Interestingly, we have only three types of receptors for sight but an amazing one hundred distinct classes of smell receptors. We can distinguish an infinite number of smells even at very low concentrations. It is the ONLY sense linked directly to the limbic brain. The response is instant and so are the effects on the brain’s mental and emotional responses and our body chemistry.

Intriguing new research has also helped us recognize that the benefits of aroma extend far beyond just emotional regulation. In addition to influencing the limbic region of the brain, olfactory centers are also intricately linked with the hypothalamus, an area of the brain more familiarly nicknamed the “visceral control center” because it controls physiologic functions throughout the body. The hypothalamus exerts its powerful influence by interacting directly with the pituitary gland, or “master gland,” a small gland located in the brain. The pituitary gland secretes hormones involved in the regulation of blood pressure, hunger and thirst signals, thyroid function, sleep cycles, production of sexual hormones, and memory, among other things. Because of the direct link of the olfactory system to this area of the brain, aroma is capable of interacting directly with the hypothalamus, influencing neurochemistry throughout the body, and, in turn, potentiating powerful health outcomes.

olfactory-receptors

How Essential Oils Work with the Limbic System

Herein lies the power and beauty of using essential oils for limbic health. Their aromas are one hundred to 10 thousand times more concentrated and more potent than the solid form of a plant. Due to their unique ability to bypass the blood-brain barrier and their concentrated aromatic compounds, pure essential oils can provide significant benefits to individuals who desire to improve limbic system function.

When inhaled, essential oils enter the olfactory system and directly affect the amygdala and therefore impact mood and emotional response; thus they can be beneficial in reprogramming the significance that individuals have attached to past experiences and can initiate rapid responses both physically and emotionally in the brain and the rest of the body. Inhalation of essential oils with the resulting aromatic exposure is the most effective method of impacting the brain.

It is important to know that many apparently physical and seemingly unrelated effects are associated with limbic system imbalance because activities of the limbic system are so deeply integrated with other body systems.

Essential Oils for Limbic System Support

Single Oils

Frankincense — supports healthy cellular function; crosses the blood-brain barrier.*

Melissa — Lessens stress and promote emotional well-being.

Patchouli — Provides grounding and balance emotions; can cross the blood-brain barrier.

Rosemary — Helps reduce nervous tension and occasional fatigue*; enhances cognitive performance, memory and mental alertness.

Sandalwood (Aloes) — promotes optimal brain function; crosses the blood-brain barrier.

Spikenard — can cross the blood-brain barrier.

Thyme — promotes a sense of alertness.

Vetiver — Is rich in sesquiterpenes, which gives it a grounding effect; can cross the blood-brain barrier.

Blends

Balance grounding blend — Evokes feelings of tranquility and balance.

Citrus Bliss invigorating blend — diffuse to help reduce stress and uplift a bad mood.

Cheer Uplifting blend — Promotes feelings of optimism, cheerfulness, and happiness; counteracts negative emotions of feeling down, blue, or low.

Clarycalm — Helps balance mood throughout the month.

Console Comforting blend — Promotes feelings of comfort and hope.; Counteracts negative emotions of grief, sadness, and hopelessness.

Elevation joyful blend — promotes feelings of confidence and self-worth.

Forgive renewing blend –Promotes feelings of contentment, relief, and patience; Counteracts negative emotions of anger and guilt.

Motivate encouraging blend — Promotes feelings of confidence, courage, and belief; Counteracts negative emotions of doubt, pessimism, and cynicism.

Passion inspiring blend — Ignites feelings of excitement, passion, and joy; Counteracts negative feelings of boredom and disinterest.

Past Tense tension blend — Helps provide grounding and balanced emotions.

Peace reassuring blend — Promotes feelings of peace, reassurance, and contentment; Counteracts anxious and fearful emotions.

Serenity calming blend — Lessens feelings of tension and calms emotions.

Supplements

Bone Nutrient Lifetime Complex™ — Provides optimal levels of vitamins and minerals essential for developing and maintaining healthy bone mass and density.*

Alpha CRS® + cellular Vitality Complex — Supports healthy cellular immune function.*

doTERRA A2Z Chewables™ — Contains a superfood blend that helps support overall health and wellness.*

Zendocrine Detoxification Complex — Helps cleanse the body of toxins and free radicals that can slow the body’s systems down.*

xEO Mega® Essential Oil Omega Complex — Promotes healthy cardiovascular, nervous, and immune system function.*

™ Whole Food Nutrient — Supports healthy immune function.*

 Usage Tips

For most effective use of essential oils for limbic system benefits:

Topical — Apply oils topically to forehead, back of skull (especially in occipital traingles), under nose, roof of mouth (place oil on pad of thumb, place on roof of mouth and suck). Use reflex points on foot for brain, namely underside of big toe, also reflex points on outer ear for brain.

Aromatic — Diffuse oils or inhale oils of choice to stimulate brain allowing entry through the nose to olfactory system. This is the most effective way to affect the limbic system.

Caution

Do no use essential oils internally unless they are labeled for dietary use. Look for the Supplement Facts box on the label. Avoid oils labeled “for external use only”, “for aromatic use only”, “not for internal use,” or “do not ingest.”

REFERENCES

Ceccarelli I, Lariviere WR, Fiorenzani P, et al. Effects of long-term exposure of lemon essential oil odor on behavioral, hormonal, and neuronal parameters in male and female rats. Brain Res. 2004;1001 (1-2):78-86.

Conrad P, Adams C. The effects of clinical aromatherapy for anxiety and depression in high risk postpartum woman – a pilot study. Complement Ther Clin Pract. 2012;18(3):164-168.

Fayazi S, Babashahi M, Rezael M. The effect of inhalation of aromatherapy on anxiety level of patients in preoperative period. Iran J Nurs Midwifery Res. 2011;16(4):278-283.

Inouye S, Uchida K, Yamacuchi H. In-vitro and in-vivo anti-Trichophyton activity of essential oils by vapour contact. Mycoses. 2001. 44:99-107.
Lehrner J, Eckersberger C, Walla P, et al. Ambient odor of orange in a dental office reduces anxiety and improves mood in female patients. Physiol Behav. 2000;71(1-2_:83-86.

McCaffrey R, Thomas DJ, Kinzelman AO. The effects of lavender and rosemary essential oils on test-taking anxiety among graduate nursing students. Hollist Nurs Pract. 2009;23(2):88-93.