Some researchers have been trying to understand why mothers love their children:

When it comes to biological mechanisms of empathy, scientists are particularly interested in oxytocin, the so-called “love hormone.” High oxytocin levels predict sensitive parenting, but it isn’t clear how the oxytocin-related gene might generate variation in empathy and parental behavior.

One possible explanation is epigenetic changes to the gene — a way of altering gene function without changing the actual DNA sequence. Specifically, “DNA methylation” — the addition of a chemical group called the “methyl” group at specific locations — in the oxytocin gene (called OXT) has been associated with personality traits and brain structure in humans.

This raises a question: can methylation of OXT influence empathy in mothers? A team of scientists at University of Fukui in Japan, led by Prof. Akemi Tomoda, decided to find out, in a study published in Psychoneuroendocrinology.

University of Fukui, “Mother’s Empathy Linked to ‘Epigenetic’ Changes to the Oxytocin Gene” at Neuroscience News (The paper is open access.)

The researchers found that, in a study on 57 Japanese mothers of young children, oxytocin played a role in promoting empathy.

A couple of key issues are worth noting:

The authors depend on epigenetics to make their case. Epigenetics involves the question of the expression of genes. Yes, we inherit genes but we don’t inherit the way our genes change over time, depending on our experiences.

Even identical twins in late life don’t have the same genes later in life Scientists have only recently discovered that fact, due to genome mapping. It’s because some genes are expressed and some are not. The methylated ones are not.

Okay, that’s really important for longterm health (in one sense, you are what you eat, and so forth). But does it really affect how moms feel about their kids?

Which brings us to the other issue: Pointing to oxytocin as some sort of Big Explanation for human emotions.

Oxytocin is a hormone produced in the hypothalamus and secreted by the pituitary gland, related to childbirth. It doubtless has a variety of functions but it has become a bit of a pop neuroscience cult: “Oxytocin (The Love Hormone): Benefits + How to Increase Levels,” “Oxytocin is a hormone and a neurotransmitter that is involved in childbirth and breast-feeding. It is also associated with empathy, trust, sexual activity, and relationship-building,” “Why Is Oxytocin Known as the ‘Love Hormone’? And 11 Other FAQs”

Some have attempted to debunk the myths. For example,

Oxytocin has another side to it that makes it something less than Love Potion No. 9. Recent research shows that it can intensify a negative memory of a social experience—such as the recollection of your boss yelling in your face in front of co-workers. It may even increase the likelihood of aggression and violence toward others who are not part of your social group.

Oxytocin without question has an influence on social dealings, but its effect may depend heavily on circumstance. The American Psychological Association’s Science Watch had two great quotes from scientists about oxytocin that caution against pigeonholing it as having any fixed role in governing social relationships:

Gary Stix, “Fact or Fiction?: Oxytocin Is the “Love Hormone”” at Scientific American (September 8, 2014)

But maybe the main problem is a bigger one. Researchers are looking for an explanation of an immaterial human quality like compassion in a purely material quality like oxytocin. And it just isn’t there.

They’ll keep looking. We will hear more, maybe cleverer, theories. But the Big Materialist Answer still won’t be there.

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