Chemistry is a trendy word these days. A film's success or failure is often attributed to the chemistry, or lack of it, between its actors. When two people meet for the first time and hit it off, they have a “great chemistry”,
while workplace issues often stem from “bad work chemistry”.
Love was the first relationship description to move away from the realms of physics and biology to the cauldron of heady molecules: endorphins, testosterone and oxytocin and get the identity of a sizzling chemical reaction. Do the laws of chemistry that circumscribe love hold true for other human relationships, too? Are the filial bonds that hold people together merely a set of chemical equations when broken down to the molecular level? Is there a chemical formula for every emotion?
Scientists across the globe have been working on unravelling the secrets of social neuroscience, a trendy new branch of research. There is one theory that considers every human being as a molecule, whose interactions with other individuals are like those between two giant molecules, forming affinity or repelling bonds the same way as a molecule of oxygen would react with hydrogen or iron. Another group feels that most interpersonal interactions are the play of chemicals released by these individuals, under instructions from their respective genetic codes.
A study conducted a few decades ago showed that a group of girls who lived in a confined space would have their menstrual cycles synchronised. This made scientists wonder if there were chemical cues that were making the group behave similarly, says Sanjeev Jain, professor of psychiatry at National Institute of Mental Health and Neurological Sciences (Nimhans), Bangalore. “Similar cues must be triggering complex behaviours in people, governing group activities, courtship and mating,” says Sanjeev.
For instance, the double income nuclear family culture of present times is showing an increasing number of youngsters affected by the maternal social deprivation syndrome. “The absence of parents for long hours and insufficient bonding affects the secretion of most hormones from the brain's pituitary glands, thereby affecting general growth, wellbeing and social skills,” says Dr S.K. Wangnoo, senior consultant endocrinologist at Indraprastha Apollo Hospitals, Delhi. Here again, there must be strong chemical cues from the parents that encourage development in the youngster.
Psychiatrists and endocrinologists loosely club individuals into three clusters. “Cluster A people have high levels of dopamine and are the most eccentric,” says Dr Kushal Jain, psychiatrist at Vidyasagar Institute of Mental Health and Neurological Studies, New Delhi. “They don't mix well with others and do things their own way. They are fine to work with as long as they are not disturbed too much. Cluster B people are outgoing. They are good leaders but not necessarily good team members. These people are found to be low in dopamine, a pleasure hormone. Since their pleasure pathways don't work too well because of a lack of dopamine, they are constantly trying to activate the pathways, which reflects in their social behaviour. These people also have interpersonal problems with others of their cluster type. Cluster C people are affable, as they have low levels of serotonin, a stress management chemical. Since this cluster lacks stress coping skills, it automatically tries to avoid conflict.”
Extremely low serotonin levels, however, are associated with mental disorders like depression. It isn't always levels of a chemical that affect relationships. Sometimes it is how a person's body reacts to the chemical. For instance, people with social anxiety disorders are often extra sensitive to the effects of serotonin.
These clusters could explain several interpersonal behaviours. Two constantly bickering colleagues might both be dopamine-starved, while a calm, affable person might be running low on serotonin. Will a calm person get aggressive if injected with serotonin? “The creator wouldn't get the variety of individual personalities we see today if he had to depend on just dopamine and serotonin,” says Mumbai-based social psychiatrist Harish Shetty. “Each human being should be considered a laboratory of trillions of molecules. Interaction with another such laboratory will naturally set off innumerable chemical reactions that will ultimately forge the relationship between the two.”
Chemicals don't work solo, they like to work in a group. Human beings are the most evolved species and can understand each other's feelings. They have empathy. Sanjeev suggests that mirror neuron pathways in the brain play a role here. These pathways were discovered around three decades ago and have caught the fancy of neurologists and neuropsychiatrists ever since.
Why do opposites attract? According to Jain, the attraction might happen because they see in the other what they may like to see in themselves, and forge the bond through the mirror pathways.
US-based scientist Dr V.S. Ramachandran's research suggests that empathy itself is not a metaphysical, social phenomenon, but has a neurological basis. In his study, he gave a set of people mild electric pokes, which fired their mirror neurons for pain. The same set of neurons fired up in the same way when these people saw someone else being poked. Understanding someone's feelings is what we call empathy. Ramachandran calls these neurons the Dalai Lama neurons.
Scientists theorise that even a human's moral fibre is woven with the yarn of chemicals, mainly large peptide chains of molecules like hormones. Oxytocin and progesterone are the toppers in this category, being associated with lofty virtues like altruism and empathy. One research group in the west developed a nasal spray with oxytocin as the main component and, in a study, showed that inhaling it lowered the social fears of the subjects, thereby making them more trusting.
Oxytocin is released in copious amounts during childbirth and lactation. “Delivering and bringing up a child, often at the cost of huge personal risk, requires high levels of selflessness,” says Sanjeev. So, naturally, researchers have studied this ancient molecule in depth. Released during hugging and kissing, oxytocin has earned appellations like “the love hormone” or “the cuddle hormone”. It is seen in high levels among prairie wolves, an extremely monogamous species, indicating oxytocin's role in fidelity. In pop science, oxytocin is the tend-and-befriend chemical, just as adrenaline is the fight-or-flight hormone.
Progesterone, which is present during pregnancy, is regarded as the nurturing hormone, and is also called the fidelity hormone. “In complex species, childbirth and childcare are taxing processes requiring the participation of both parents. Fidelity is, therefore, a requisite for survival,” says Sanjeev.
Social endocrinology is still in its nascent stages and every study throws up new information. Chemicals do not always instruct us on how to behave and our behaviour, too, can release a particular set of chemicals. A recent study by the University of Michigan shows that female bonding causes a surge in progesterone levels, increasing their general levels of wellbeing. This is in contrast to the established thought that progesterone caused bonding in the first place. The study also showed that these women, when awash with progesterone surges, were also more inclined to sacrifice, even at the cost to personal risk.
Positive chemical cocktails coursing through the system will not amount to much, however, unless supported by the right genetic code, physical maturity and other factors. The nesting behaviour triggered by progesterone works best when the body is in its prime reproductive years. An immature individual might not be able to utilise the affiliation bonds induced by the hormone as effectively.
“Uptake of chemicals depends on the development of neuronic pathways in the brain,” says Sanjeev. Does that explain why people you could never get along with during your youth now seem tolerable? Similarly, adrenaline, a corticosteroid, is secreted in times of sudden stress, triggering a cascade of reactions from dilated pupils to increased heartbeats, making the individual acutely self-aware and focussed on the situation.
Yet, some decide to fight the adversary, while others choose flight. “Herein comes personality type, which is itself etched by individual chemical concentrations in their systems,” says Wangnoo.
Behavioural scientist Anindya Sinha of the National Institute of Advanced Studies, Bangalore, has been studying macaques for two decades. He has made interesting observations, based on just one molecule: a transporter of serotonin. Most macaques have only one variety of this gene, only the aggressive rhesus [where the pecking order is stringent] and egalitarian bonnet macaques [who live in democratic communities] show different expressions of the gene, or polymorphism, as it is scientifically called. Sinha's studies demonstrate that this genetic variety is responsible for a commonly shared trait between these otherwise different macaques: adaptability. Individuals with the long gene sequence are better adapted to stress than those with the short one. But the coexistence of both gene forms within the population gives the cluster better adaptability skills, thus boosting their survival chances even in changing environments.
At a human level, Sinha extends this theory to explain why certain socially negative traits like alcoholism and drug addiction persist. These traits have been associated with the expression of particular genes. Scientists believe that genes which are bad for the survival of species are eventually weeded out of populations. But the same gene that makes a person prone to addiction might also be responsible for a positive trait like adaptability or affability that is beneficial for species survival. “My studies focussed on just one gene expression,” said Sinha. “Individual behaviours are sculpted when hundreds of genes act in concert. Yet, we are not just a manifestation of gene expression, because there are so many other forces also at play. There is a chemistry out there for sure. But how much is chemistry and how much is beyond it, is something we don't know when we will decipher.”
The absence of parents for long hours and insufficient bonding affects the secretion of most hormones from the brain's pituitary glands, thereby affecting general growth, wellbeing and social skills.
Dr S.K. Wangnoo, senior consultant endocrinologist, Indraprastha Apollo Hospitals, Delhi