The Emotional Brain

This is supplemental information for this topic marked by the little computer icon in the book, Irritable Bowel Syndrome and the MindBodySpirit Connection, by William B. Salt II, M.D. and Neil F Neimark, M.D. (Columbus: Parkview Publishing, 2002). Click here to learn more about the book and/or to purchase it.

The stress response is a bodily expression of emotion mediated by the limbic system, or emotional motor system of the central nervous system that is designed to be life saving by way of the fight or flight response. But similar responses can occur in situations that are perceived as threats but which are not life-threatening, such as having to give a speech or remembering a previously stressful event. Furthermore, the emotional stress response commonly, but not necessarily, includes subjective emotional feelings, such as fear, anxiety, and/or anger.

Dr. Joseph LeDoux is a brain scientist at the New York University Center for Neural Science. Click here for his laboratory web site. He has shown that emotions are triggered by the central nervous system in response to distinct environmental situations or to the recollection of memories related to such situations. The basic mechanisms that generate emotional responses of the body evolved long before the conscious feeling of emotions evolved in humans. Emotional responses are essential for survival of all living beings. For example, the emotions of fear and anger and the associated fight or flight response are necessary in order to avoid harm from a predator or aggressor. The emotion of love, or attachment, is essential for bonding between individuals. The emotion of disgust probably evolved as food aversion in order to prevent the ingestion of potentially harmful substances.

The body consistently responds to stressors in an automatic way that is specific for the stressor, often without our being aware of the response. In other words, when the body responds to stressful situations, conscious emotional feelings may or may not be associated.

So whenever an emotion, such as fear or anger is triggered, a network of brain areas referred to as the limbic system (also called the emotional brain) generates a pattern of outputs, which cause a biologic response in the body. These responses are programmed, much like a computer program and expressed via the MindBodySpirit Communication systems of the central nervous system, the autonomic nervous system, and the neuropeptide chemical messenger systems. Facial expressions are an example of the expression of emotion in the body. All human beings produce similar expressions associated with emotions, such as fear, anger, and sadness. Other examples are tightening of the muscles associated with fear and slumping of the shoulders with sadness.

Emeran Mayer, M.D. has applied Dr. LeDoux’s concepts regarding the emotional brain to the gastrointestinal tract (Mayer EA, Naliboff B, and Munakata. The evolving neurobiology of gut feelings. Prog Brain Res 2000;122:195-206). Click here to read an abstract of this medical journal article. Even though we may be completely unaware of any associated emotional feeling, such as fear, anxiety, or anger, the programmed emotional responses are generated in our internal organs, particularly the gastrointestinal tract (gut). For example, the emotion of fear is associated with the inhibition of the upper gut (stomach and duodenum) contractions and secretions, leading to the symptoms of fullness, bloating, loss of appetite, nausea, and even vomiting. The emotional gut response of fear stimulates the lower gut (sigmoid colon and rectum), which can cause diarrhea, cramping, and abdominal pain. From the perspective of evolution, this response program or pattern evolved in order to reduce exposure of the gut to ingested food and waste material while energy is shunted to the cardiovascular and musculoskeletal systems in order to maximize the effects of the fight and flight response and survival potential. In other words, the last thing that your body needs to be doing when your life is threatened is to be digesting your lunch! And to emphasize the point again, all of this emotional gut response can occur without your being consciously aware of the emotional feeling of fear.

These remarkable and complex programs that have evolved to activate the stress response are counterbalanced by mechanisms to turn it off when the threat has passed or to blunt the response with repeated occurrences of the same stressor. These systems of activation and deactivation of the stress response have evolved over millions of years and have been perfected in order for animals to deal with survival threats in the cycle of prey and predators. But our lives are usually not threatened in modern society. Instead, these same mechanisms are turned on by the hassles and hustles of every day living. Unfortunately, this good stress can become bad stress through the process of allostatic load, which is the wear and tear of severe, repeated, or sustained chronic stress. Symptoms, syndromes, illness, and disease can result.

You can further explore Dr. Joseph LeDoux’s important concepts regarding the emotional brain by reading his book, The Emotional Brain: The Mysterious Underpinnings of Emotional Life. (New York: Touchstone Books, 1998). This book provides a lucid discussion of the emotional stress response systems. A very important observation is that the expression of stress and emotion in the body is not necessarily accompanied by cognitive and conscious awareness of anxiety or of fear. In other words, when stress triggers an emotional fear response expressed in the digestive tract as pain, cramping, and disturbances of bowel function, or in the muscles as pain and discomfort, the gastrointestinal and bodily distress may or may not be accompanied by a mental sense of fear or of anxiety. This makes it easier to understand how depression can be associated with many different bodily symptoms, and how these bodily symptoms may not be associated with much if any sadness or depression of mood.

 


 

The Little Brain in the Gut

This is supplemental information for this topic marked by the little computer icon in the book, Irritable Bowel Syndrome and the MindBodySpirit Connection, by William B. Salt II, M.D. and Neil F Neimark, M.D. (Columbus: Parkview Publishing, 2002). Click here to learn more about the book and/or to purchase it.

You have two brains: one in your head and another in your gut. Dr. Jackie D. Wood is a renowned physiologist at The Ohio State University. He calls the second brain, "the-little-brain-in-the-gut." This enteric nervous system is part of the autonomic nervous system and contains over one hundred million neurons, which is as many as are in the spinal cord. This complex network of nerves lines the walls of the digestive tract form the esophagus all the way down to the colon. This little brain in the gut is connected to the big brain by the vagus nerves, bundles of nerve fibers running from the GI tract to the head. All neurotransmitters, such as serotonin that are found in the brain are also present in the gut.

Dr Wood has discovered that this little-brain-in-the-gut has programs that are designed for our protection and which are very much like computer programs. They respond to perceived threats in the same way that the limbic system or the emotional brain does. So the threat of a gastrointestinal infection can activate the program that increases gut contractions in order to get rid of the infection. The symptoms are abdominal cramping and diarrhea.

Dr. Wood has determined that a type of cell found in the body and the gut, called the mast cell, is a key to understanding the connection of the big brain in the head with the little-brain-in-the-gut. Mast cells are involved in defense of the body. In response to certain threats or triggers, such as pollen or infection, mast cells release chemicals, such as histamine, that help to fight off the invader. Histamine is one of the chemicals that causes the symptoms of an allergy or a cold. When an infection of the gut occurs, such as food poisoning or gastroenteritis, the mast cells of the gut release histamine. The little-brain-in-the-gut interprets the mast cell signal of histamine release as a threat and calls up a protective program designed to remove the threat – at the expense of symptoms: abdominal pain and diarrhea.

The brain to mast cell connection has a direct clinical relevance for irritable bowel syndrome and other functional gastrointestinal syndromes. It implies a mechanism for linking allostasis and the good stress response to irritable states (e.g., abdominal pain and diarrhea) of the gut. Mast cells can be activated to release histamine in response to perceived psychological stress, whether the stressor or trigger is consciously perceived or not. So the end result is the same as if an infection activated the program in the-little-brain-in-the-gut: abdominal pain and diarrhea.

Click here to review the abstract of a scientific medical journal discussion of a possible link between psychological stress, enteric infection, food allergy and gut hypersensitivity in the irritable bowel syndrome.

 


 

Vitamins

This is supplemental information for this topic marked by the little computer icon in the book, Irritable Bowel Syndrome and the MindBodySpirit Connection, by William B. Salt II, M.D. and Neil F Neimark, M.D. (Columbus: Parkview Publishing, 2002). Click here to learn more about the book and/or to purchase it.

 

What Vitamins Should I Be Taking, Doctor?

Here is advice from Harvard experts published in the world’s most prestigious medical journal, the New England Journal of Medicine (Willett WC and Stampfer MJ. What vitamins should I be taking, Doctor? New England Journal of Medicine. 2001;345:1819-1824). Click here to purchase this article from the New England Journal of Medicine.

Conclusions and Recommendations

Given the greater likelihood of benefit than harm, and considering the low cost, we conclude that a daily multivitamin that does not exceed the RDA of its component vitamins makes sense for most adults…. Substantial data suggest that higher intakes of folic acid, vitamin B6, vitamin B12, and vitamin D will benefit many people, and a multivitamin will ensure an adequate intake of other vitamins the evidence of benefit is indirect. A multivitamin is especially important for women who might become pregnant; for persons who regularly consume one or two alcoholic drinks per day; for the elderly, who tend to absorb vitamin B12 poorly and are often deficient in vitamin D; for vegans, who require supplemental vitamin B12; and for poor urban residents, who may be unable to afford adequate intakes of fruits and vegetables.

Many multivitamins also contain essential minerals, although the doses of some of these minerals, such as calcium, are well below the RDA. Although we have not discussed minerals here, there is less evidence supporting the existence of a benefit for mineral supplements, with the exception of the additional iron required by some premenopausal women.

Although one could measure blood levels to identify those who would benefit most from multivitamins, this would be much more expensive than simply recommending that all adults take a supplement (at a typical cost of $20 to $40 per year). Education regarding nutrition is vitally important, but it has been far less effective than supplementation or the fortification of food in raising blood folic acid levels. However, a vitamin pill is no substitute for a healthful lifestyle or diet, because foods contain additional important components, such as fiber and essential fatty acids. In particular, a vitamin supplement cannot begin to compensate for the massive risks associated with smoking, obesity, or inactivity. The cost of a multivitamin supplement is so low – similar to that of about a quarter of a serving of fruit or vegetables – that it is unlikely to displace healthful foods in most persons’ budgets.

We also believe that vitamin E supplements are reasonable for most middle-aged and older Americans who are at increased risk for coronary artery disease. Evidence is still accruing, but even assuming a low probability that vitamin E will eventually be proved efficacious (and we view the probability as fairly high), the likelihood of a benefit would still outweigh the very low probability of harm. We would offer a vitamin E supplement in a dose of 400 IU…, with the suggestion that we review this practice annually as more information becomes available. Finally, although we do not recommend additional vitamin supplements at present, the relevant evidence remains far from complete.

 


 

Weight Loss

This is supplemental information for this topic marked by the little computer icon in the book, Irritable Bowel Syndrome and the MindBodySpirit Connection, by William B. Salt II, M.D. and Neil F Neimark, M.D. (Columbus: Parkview Publishing, 2002). Click here to learn more about the book and/or to purchase it.

Click here to visit the National Institute of Diabetes & Digestive & Kidney Diseases Weight Loss and Control website.

 


 

Whole Healing System

This is supplemental information for this topic marked by the little computer icon in the book, Irritable Bowel Syndrome and the MindBodySpirit Connection, by William B. Salt II, M.D. and Neil F Neimark, M.D. (Columbus: Parkview Publishing, 2002). Click here to learn more about the book and/or to purchase it.

 

Elliott S. Dacher, M.D., a pioneer in the emerging medicine of the future, has developed an innovative and expanded approach to health and healing. His approach evolved from both his personal exploration of these issues and his extensive experience as a practicing internist participating in over 50,000 medical visits. Click here to learn more about Dr. Dacher and his Whole Healing System and about his books, Whole Healing and Intentional Healing.