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The Truth About Loneliness

The pathophysiology of the perception of isolation

This post is in response to
4 Disorders That May Thrive on Loneliness

The key to removing unhealthy habits is removing the reasons you have them. Loneliness is a major cause of many unhealthy habits and physical illnesses[1] Loneliness is not as much an absence of company, or lack of kind, as it is a perception of isolation that takes a serious toll on your health. Compulsive overeaters and addicts often turn to food or their drug of choice to alleviate the anxiety that loneliness causes because it is a severe stressor in the brain due to biology, evolution and our survival instinct.[2-4]

Evolutionary Implications

Connection to others is a survival issue for members of a social species. For the ancients, separation from the group meant greater vulnerability to predators, and less access to food and mating opportunities. That was then; this is now. Our predators are in zoos or extinct. Circumstances have changed, but our biology has not. While the thinking part of our brains may know that there is little chance of jackal attack, our old mammal brain that regulates the stress of isolation does not think. Its motto is: survive now and ask questions later hence fight-or-flight.[5]

That becomes problematic because it easy for the complexities of our modern society to confuse the old brain, especially the Ventral Tegmental Area (VTA). The VTA monitors the satisfaction of our vital needs such as breeding, social bonding and feeding. It must rely on reading cues from physiological events in the brain and the body. For example, when we have sex using birth control, the VTA thinks we are breeding because the physiological events occurring in our bodies are the same as if we were mating. Thus, it is happy and releases dopamine (the brain’s happy drug). While the VTA's vulnerability to misreading physiological cues may be an asset in certain sexual scenarios, it is a liability when processing the perception of social isolation because it perceives it as evidence of separation from the herd, which it interprets as a serious survival threat. Thus, when this occurs the VTA hits the panic button, and turns it up to 12 or higher, depending on the person. [6-15] Like all evolutionary traits, subjectivity is involved for various reasons. For example, some people do not perceive isolation as stressful because doing so promotes survival of the species, i.e., our explorers promote the quality of human life. Explorers often endure isolation. However, most of us are not explorers.

The Perception of Isolation and Health Consequences

Numerous studies have shown that the stress of loneliness is responsible for a myriad of health problems that affect us even at a cellular level.[2, 16] It contributes to Alzheimer’s disease, as well as sleep disorders. It is a major cause of depression, and increases risk for dementia and premature death. [17-19] A study also showed that loneliness causes an overexpression of genes in cells that produce an inflammatory response to tissue damage in the heart.[20, 21] Thus, loneliness can actually break your heart—physically.

Two of my colleagues, at UCLA, Drs. Naomi Eisenberg and Matthew Lieberman, discovered that the perception of exclusion utilizes the pain network in the brain. [22]Loneliness impairs executive functioning because stress reduces the availability of serotonin, which is vital in executive function. Thus, it impairs our ability to control thoughts, emotions, and impulses. Loneliness leads to poor health behaviors because it promotes impulses that are unhealthy, but are pleasurable.

Dr. John Cacioppo (University of Chicago), a leading researcher in loneliness, says loneliness encourages “higher fat and sugar in your diet, alcoholism, drug addiction, and less exercise”. Of course, that is true. Loneliness hurts and the natural response to pain is to reach out for something that makes us feel better. On a neurochemical level that would be the body’s natural endorphin; the brain perceives and processes loneliness as if were physical pain. Of course, what brain does not want a shot of dopamine when it can get it? For compulsive overeaters, relationship addicts, and substance abusers, we know the most likely source of that dopamine.

Most often, loneliness does not involve people who are unattractive or socially disconnected. It involves a perception that one’s social connections are not valid and viable. For example, it might be a gay person who has not come out to his or her co-workers. The perception of being isolated becomes tremendous, i.e., “they do not really know who I am. I am keeping a secret. I am all by myself.” It does not matter how much his or her co-workers reach out to the person, he or she will still feel isolated. Most often, it is not as tangible as that situation. Most often, it is just an anxiety-based perception that one “does not belong” for whatever reason. Remember, in determining what is real, the old mammal brain does not distinguish between actuality and perception.

The brain also consolidates and simplifies information for proficiency’s sake.[23-28] Thus, it could be the perceived isolation that “no one understands” when taking care of a spouse with a disability, or a differently abled child that the VTA distills into “I am disconnected from the herd, I am in crisis”. There could be various sources: extreme wealth, power, poverty, physical beauty or the antithesis of those.

It could be the singular terror that an obese person feels, living in a world where one size does not fit all. Nothing is more singular than abusive childhood experiences. Regardless of the reason, at the end of the day isolation is painful. Pain warps our perspective in a negative way and a downward synergy occurs.

Thus, the key is to remember, unless you are alone in lunar space tracking station, isolation is most often a correctable perception.

Have a splendid New Year and of course… remain fabulous and phenomenal!

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