Happiness – the Biological Basis

As we all know, the world, our country and our city is currently in the vice-like grip of the COVID-19 pandemic. Social and traditional mass media alike is flooded with a surfeit of information, knowledge and facts, most of it genuine, some of it false, and a proportion, simply crass. However, I am sure we all would have noticed a common thread running through this info overload: the exhortation to keep a positive frame of mind, stay happy and keep our spirits up.  No matter the source or subject matter, as long as it has anything to do with battling the scourge, the tail end of the message almost inevitably advises us to keep happy, calm and positive. It is an entirely different matter whether or not the authors of these advisories-be they the concerned neighbourhood auntyji/uncleji, or the heads of some of the world’s top medical institutes- actually understand the import of this part of their advice; but the fact remains that happiness, laughter or a cheerful and positive disposition in general have been shown to play a major role in healing, immunity and recovery. This state of happiness has long been the subject of research, with many theories being propounded about its origins. For long, happiness was thought to be genetic or inherited; others believed that it was caused by certain factors, like money, education and staying physically active in life. However, extensive studies have thrown up the finding that happiness is a result of several factors, both biologic and environmental.  Happiness as an emotion is formed as a general interaction between internal (endogenic) and external (exogenic) factors, each factor carrying a different weight in this relation. With this background let us walk through the biologic or scientific basis of happiness. These can be divided into several headings:

Genetic Factors

Psychobiology is the field concerned with the study of the biological basis of psychology. Two major studies have found that genetic factors account for 35-50% of happiness.  But what kind of genetic mechanisms make a person happy?  This is an important question in this field. Finding special genes in happiness is a difficult task, but recent advances in molecular genetics have uncovered new neurobiology markers of happiness. While most studies have centered on genetic factors in depression, some studies have shown correlation with certain genes (designated 5-HTTLPR and MAO-A ) and happiness.  Studies suggested an association between 5-HTTLPR and life satisfaction. This gene codes for the distribution of the neurotransmitter Serotonin in the brain cells, thus regulating feelings of well-being. Serotonin is one of the feel-good hormones that is responsible for stabilization of mood, happiness and well-being. The other gene (MAO-A), is responsible for catabolism or breakdown of other  feelgood neurotransmitters like dopamine, serotonin and noradrenaline. The more the expression of this gene, the more the chemical breakdown of these neurotransmitters, and the less the quantum of happiness and feeling of well being.

Perhaps  differences in levels of expression of these genes may be responsible for the varying reaction of different folks to the ravages of the current pandemic. On the one hand, we have the doomsdayers, with their nihilistic prophecies; on the other hand we have the diehard optimists who believe that succor is just around the corner.

Brain Circuitry & Neurotransmitters

Thoughts, feelings, emotions, mood and the like are all regulated by the brain. The emotion circuitry of the brain is very complex, involving a lot of forbidding – sounding names (prefrontal cortex, amygdale, hippocampus, anterior cingulated cortex, and insular cortex)! However, research has focused on the prefrontal cortex and its role in relation to positive and negative emotions.  The usage or activation of specific areas in the brain is manifested by increased metabolism as measured by a technique known as “functional Magnetic Resonance Imaging” (fMRI). Davidson and colleagues have reported large individual differences in baseline levels of asymmetric activation in prefrontal cortex, related to a person’s typical emotional style. Individuals with a positive emotional style show higher levels of left than right prefrontal activation at rest (using EEG or fMRI), while those with a negative emotional style tend to show higher levels of right than left prefrontal activation at rest.

Limbic system that is placed in the central area of brain has the most influence on identifying the

form of emotions. Increasing in metabolism of limbic system leads to depression in individuals. But the major role in our emotions is played by the neurotransmitters as mentioned above. Two of the most important neurotransmitters that are involved in mood are dopamine and serotonin. Positive mood and negative mood are mediated by dopamine and serotonin levels. The most influential neurochemical theory of positive mood is presented by Ashby et al. The two main elements of their theory are that: (i)positive mood is associated with (but not necessarily caused by) increased levels of dopamine in

the brain; and

(ii) some of the changes in cognition observed in positive mood are due to the increased dopamine levels associated with positive mood.

Another neurochemical agent  associated with emotional states is serotonin (5HT). Serotonin is a neurotransmitter that mediates satisfaction, happiness and optimism. Serotonin levels are reduced

in depression, and most modern anti-depressant drugs, known as serotonin reuptake inhibitors

(SSRIs), act by increasing the amount of serotonin available to brain cells. However, what is the relationship between serotonin and positive mood? Research has indicated that increased  serotonin level is related to a positive mood. Norepinephrine is another neurotransmitter that is

associated with the level of happiness. Some classes of antidepressants act by increasing the amount of norepinephrine available to the brain cells.

The much-celebrated Endorphins have also been studied as a neurotransmitter in happiness. Endorphins are endogenous opioid peptides (something akin to locally produced morphine in the body!) that function as neurotransmitters. They are released during continuous exercise, fear, love, music, eating chocolates, laughter, sex, orgasm etc. Increased levels of endorphin have been found to inhibit pain in the body.  Hence, in most diseases doctors suggest exercises such as walking, running, workouts, laughing, meditation, listening to music; all these activities are responsible for triggering release of endorphins, giving rise to a good mood and a feeling of wellbeing.

Hormones & Endocrine Glands

Endocrine glands release various hormones directly into the bloodstream and control various processes like growth, metabolism, emotional regulation and so on. Endocrine glands include the pineal gland (located in the brain). Pituitary gland (also in brain), adrenal glands (on each kidney), pancreas, testes and ovaries. In several studies, the role of some glands in regulating mood states have been evaluated. The endocrine glands most related to mood states are the pituitary and adrenal glands. Studies have suggested that some hormones from these glands have a fundamental role in happiness and mood regulation.

Melatonin

Melatonin or n- acetyl- 5- methoxytryptamine is a hormone that is secreted by the pineal gland at night. It is linked with how our body gets ready for sleep. Melatonin levels vary in 24-hour cycles and are reduced in bright light. Its level peaks between 9 and 10 pm, following which it gradually decreases by morning. Studies have shown that melatonin level is related to happiness levels. Melatonin has a role in depression and some of antidepressants increase the melatonin in blood.

Cortisol

Hydrocortisone is a well- known Glucocorticoid in the body that is released from adrenal glands.

This hormone is released in response to inflammation. The role of this hormone in psychological process is managing stress. Several studies investigated the relation between Cortisol and depression as a contrary dimension of happiness. Cortisol has been shown to be a consistent marker for depression. High levels of morning cortisol have been have been linked to depression.

Adrenaline

Adrenaline (also known as Epinephrine) is a hormone and a neurotransmitter that is released from the

Adrenal glands.  Adrenaline has many functions in the body, regulating heart rate, blood vessel and

air passage diameters, and metabolic shifts; Adrenaline release is a crucial component of the

fight-or-flight response of the sympathetic nervous system. Therefore, adrenaline produces similar effects to Cortisol, such as increased heart rate and immune system suppression. Researches indicate that urinary adrenaline is a good predictor of happiness. It has been found that individuals with higher levels of “personal growth” and “purpose in life” registered lower and more stable levels of salivary Cortisol and urinary Adrenaline.

Oxytocin

A hormone released from pituitary gland which controls uterine contractions and regulate breast feeding stimulus. Recently research showed that Oxytocin causes a wide spectrum of behavioral and physiological effects mediated through receptors within the brain, such as maternal, sexual and social behaviors. Oxytocin facilitates interpersonal relationships and is associated with positive social behavior, so it stands to reason that it shares a direct relation with happiness. While social relationships have a strong effect on life satisfaction and there is a significant correlation between happiness and social relationships, it follows that Oxytocin can be a mechanism that produces happiness by facilitating social relationships.

Physical Health

Several studies have investigated the association between physical health and happiness.  Several studies demonstrated a significant correlation between positive mood and physical health. Researchers stated that people with happiness experience a longer lifespan. People with happiness behave healthier (weight control and healthy lifestyle practices) than others. Having positive mood and happiness correlated with decreased incidence of some illnesses such as hypertension, cardiovascular disease and obesity. Researchers have also found a strong relation between areas of the brain that manage weight and metabolism and areas that control cognition and emotions. Recent studies showed that people with happiness showed better survival with cancer.

To conclude, happiness is not just a matter of reacting to one’s surroundings or circumstance. If that were so, literally EVERYONE in our country would be sad and unhappy right now. However, since as we all know, “ we are in this together,” perhaps our genes and our brain neurochemicals are also to be called to account for how happy we may or may not be in these troubled times. While that is no excuse to lie back and worry about the situation, the least we can do to alleviate the doom and gloom around us is to help ourselves stay safe and exhort those around us to do the same, whilst reminding them that while the happiness component may not always be in our control, the safety measures surely are; that dose of optimism itself should go a long way in increasing somewhat, the quantum of wellbeing we all so badly lack!

“…remember, the light at the end of the tunnel may be you. Good night!”

–From  “Amazin’” by Aerosmith.