GoSouth

South African, Credible and Current

  • HOME
  • NEWS AND FEATURES
    • News & Opinion
    • Covid-19
    • Cape Independence
  • FINANCE
  • SCIENCE
  • INTERESTING
  • NATURE & ANIMAL TALK
  • LIFESTYLE ART
  • HISTORY
    • Cape South Peninsula

How much do our genes restrict free will?

Social media algorithms, artificial intelligence, and our own genetics are among the factors influencing us beyond our awareness. This raises an ancient question: do we have control over our own lives?

Hannah Critchlow, Science Outreach Fellow at Magdalene College, University of Cambridge – 14 October 2020

Many of us believe we are masters of own destiny, but new research is revealing the extent to which our behaviour is influenced by our genes.

It’s now possible to decipher our individual genetic code, the sequence of 3.2 billion DNA “letters” unique to each of us, that forms a blueprint for our brains and bodies.

This sequence reveals how much of our behaviour has a hefty biological predisposition, meaning we might be skewed towards developing a particular attribute or characteristic. Research has shown genes may predispose not only our height, eye colour or weight, but also our vulnerability to mental ill-health, longevity, intelligence and impulsivity. Such traits are, to varying degrees, written into our genes — sometimes thousands of genes working in concert.

Most of these genes instruct how our brain circuitry is laid down in the womb, and how it functions. We can now view a baby’s brain as it is built, even 20 weeks before birth. Circuitry changes exist in their brains that strongly correlate with genes that predispose for autism spectrum disorder and attention deficit-hyperactivity disorder (ADHD). They even predispose for conditions that might not emerge for decades: bipolar disorder, major depressive disorder and schizophrenia.

Increasingly we are faced with the prospect that predispositions to more complex behaviours are similarly wired into our brains. These include which religion we choose, how we form our political ideologies, and even how we create our friendship groups.

Nature and nurture are intertwined

There are also other ways our life stories can be passed down through generations, besides being inscribed in our DNA.

“Epigenetics” is a relatively new area of science that can reveal how intertwined nature and nurture can be. It looks not at changes to genes themselves, but instead at the “tags” that are put on genes from life experience, which alter how our genes are expressed.

One 2014 study looked at epigenetic changes in mice. Mice love the sweet smell of cherries, so when a waft reaches their nose, a pleasure zone in the brain lights up, motivating them to scurry around and hunt out the treat. The researchers decided to pair this smell with a mild electric shock, and the mice quickly learned to freeze in anticipation.

Epigenetics: what impact does it have on our psychology?

The study found this new memory was transmitted across the generations. The mice’s grandchildren were fearful of cherries, despite not having experienced the electric shocks themselves. The grandfather’s sperm DNA changed its shape, leaving a blueprint of the experience entwined in the genes.

This is ongoing research and novel science, so questions remain about how these mechanisms might apply to humans. But preliminary results indicate epigenetic changes can influence descendants of extremely traumatic events.

One study showed the sons of US Civil War prisoners had an 11% higher death rate by their mid-40s. Another small study showed survivors of the Holocaust, and their children, carried epigenetic changes in a gene that was linked to their levels of cortisol, a hormone involved in the stress response. It’s a complicated picture, but the results suggest descendants have a higher net cortisol level and are therefore more susceptible to anxiety disorders.

Extreme stress in childhood is toxic to your DNA

Do we have any scope for free will?

Of course, it’s not simply the case that our lives are set in stone by the brain we’re born with, the DNA given to us by our parents, and the memories passed down from our grandparents.

There is, thankfully, still scope for change. As we learn, new connections form between nerve cells. As the new skill is practised, or the learning relived, the connections strengthen and the learning is consolidated into a memory. If the memory is repeatedly visited, it will become the default route for electrical signals in the brain, meaning learned behaviour becomes habit.

Take riding a bike, for example. We don’t know how to ride one when we are born, but through trial and error, and a few small crashes along the way, we can learn to do it.

What is brain plasticity and why is it so important?

Similar principles create the basis for both perception and navigation. We make and strengthen neural connections as we move around our environment and conjure our perception of the space that surrounds us.

But there’s a catch: sometimes our past learnings blind us to future truths. Watch the video below — we’re all biased towards seeing faces in our environment. This preference causes us to ignore the shadow cues telling us it is the back end of a mask. Instead, we rely on tried and tested routes within our brains, generating the image of another face.

You probably won’t notice that Albert Einstein’s face is the back side of a mask, rather than the front, because our brains are biased towards seeing faces in our environment.

 
This illusion illustrates how difficult it can be to change our minds. Our identity and expectations are based on past experiences. It can take too much cognitive energy to break down the frameworks in our minds.

Elegant machinery

As I explore in my latest book published last year, The Science of Fate, this research touches on one of life’s biggest mysteries: our individual capacity for choice.

For me, there’s something beautiful about viewing ourselves as elegant machinery. Input from the world is processed in our unique brains to produce the output that is our behaviour.

However, many of us may not wish to relinquish the idea of being free agents. Biological determinism, the idea that human behaviour is entirely innate, rightly makes people nervous. It’s abhorrent to think that appalling acts in our history were perpetrated by people who were powerless to stop them, because that raises the spectre that they might happen again.

Perhaps instead, we could think of ourselves as not being restricted by our genes. Acknowledging the biology that influences our individuality may then empower us to better pool our strengths and harness our collective cognitive capacity to shape the world for the better.The Conversation

This article is republished from The Conversation under a Creative Commons license. Read the original article.

  • Share
  • Twitter
  • Facebook
  • WhatsApp
  • Email
  • LinkedIn
  • Skype
  • Telegram

Related Posts

  • How much of climate change is natural? How much is man-made?

    Mark New, Director, African Climate and Development Initiative, Univ. of Cape Town As someone who…

  • What is a virus? How do they spread? How do they make us sick?

    Some viruses have an outer envelope made of lipids, which are fatty organic molecules. The…

  • How our African ancestors made sound in the Stone Age

    The Middle and Later Stone Age, which lasted from about 300 000 to 300 years…

  • How Chameleons Change Colour

    Chameleons have a mobile lattice of nanocrystals on the surface of their skin which come…

  • How STRESS affects your Brain

    Stress causes the release of a hormone called cortisol. This stress hormone has been shown…

Contact US

  • Email
  • Facebook
  • Twitter

Search this Website

HELP HOTLINE 0800 029 999

previous arrow
next arrow
Slider

Most Recent Posts

  • Marine life is fleeing the equator to cooler waters and could trigger a mass extinction
    Anthony Richardson, Professor, The University of […]
  • Understanding the ANC Factional Battles: A Deep History and an Uncertain Future!
    Stef Terblanche, FW de Klerk Foundation – 8 […]
  • Retirement village living on your terms
    Riaan Campbell, Advisory Partner, Citadel – 7 […]
  • An ancient San rock art mural in South Africa reveals new meaning
    David M. Witelson, PhD candidate, University of the […]
  • Expropriation Bill offers no solutions to land reform
    The Bill covers far more than land, it covers homes, […]
  • Scientists are hoping to redefine the second – here’s why
    Ben Murdin, Professor of Photonics and Quantum […]
  • Repo rate remains unchanged at 3.5%
     STATEMENT OF THE MONETARY POLICY COMMITTEE – […]
  • SOUTH AFRICA, Defend our Democracy! Defend our Constitution!
    The way in which the people’s democracy is being […]
  • Coronavirus is evolving but so are our antibodies
    Sarah L Caddy, Clinical Research Fellow in Viral […]
  • Ivermectin study boosts regulator’s court defence
    The first substantial peer-reviewed clinical trial of […]

NUMBERS TO NOTE

Gender-Based Violence Command Centre: 0800 428 428
Western Cape Women’s Shelter Movement: 082 903 8739

Police: 10111

Childline: 0861 322 322
Child Welfare SA: 0861 424 453

South African National Human Trafficking Hotline: 0800 222 777

Copyright © 2021 — GoSouth • All rights reserved • Privacy Policy • Disclaimer • Terms & Conditions • Cookie Policy

loading Cancel
Post was not sent - check your email addresses!
Email check failed, please try again
Sorry, your blog cannot share posts by email.