Nature vs. Nurture: Is it our genes or our environment?

​How many times have we wondered if a certain behavior or trait was due to our genetic makeup, or whether it was due to how our environment shaped us? You may be surprised to learn which is nature vs. nurture.
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The nature vs. nurture theory is the scientific, cultural, and philosophical debate about whether human culture, behavior, and personality are caused primarily by nature or nurture.

What exactly is nature vs. nurture?

In the context of the nature vs. nurture debate, “nature” refers to biological/genetic predispositions’ impact on human traits, and nurture describes the influence of learning and other influences from one’s environment, culture, and experience.

The debate over whether the strengths and weaknesses of people are the results of nature or nurture has, and somewhat continues to rage on. This debate has had significant social implications, particularly concerning what is thought to determine people’s ability to learn/intelligence.

Studies to determine nature vs. nurture

While certain physical traits, like skin and eye color and diseases like sickle cell anemia and Huntington’s chorea, are the result of direct genetic inheritance, virtually any pattern of thinking or behavior can be understood from the perspective of a combination of nature and nurture.

In the animal kingdom, domestication of many species is understood to be the result of encouraging domesticated behaviors (nurture), then having animals that most successfully adopt those behaviors breed with each other so it becomes part of their nature.

Several studies done on twins separated shortly after birth reveal that genetics do play a significant role in the development of certain personality characteristics, sexual orientation, and religiosity. The bond between identical twins was also suggested to be genetic by these studies, as 80% of identical twins reported that they felt closer to their twin than they did to their closest friends, despite having just met their twin.
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One study also suggested that genetics play a significant role in the development of personality: Environment had little effect on personality when twins were raised together, though it did have an effect when they were raised apart.

​How does nature vs. nurture affect our mental and physical health?

It is understood that certain physical traits, as well as the susceptibility to most physical and mental health disorders, tend to run in families. Specifically, whatever illnesses your parents, grandparents, siblings, and other biological family members have does not guarantee you will inherit them, but it does increase the likelihood that you may develop them.

On the other hand, it is understood that environmental factors often have a significant effect on whether or not you develop the health problems that run in your family. (You can change your gene expressions).

A couple of examples of how the environment (nurture) can provide a benefit, and possibly decrease your risk of getting an illness from your family are:

• If you are at risk for heart disease or diabetes, eat a healthy diet and exercise.
• If you are at risk for other conditions, for example, breast or colon cancer, get regular health screenings like mammograms and colonoscopies per your doctor's recommendations.
• Examples of how negative environmental influences can affect genetic expression include:
• Exposure to community violence increasing the likelihood of anxiety
• Depression and negative behaviors
• Children who are exposed to secondhand smoke may develop cancers more often than those who do not have that experience.
  
  

How nature affects mental health

Nature, or genetics and disposition, have been proven to be an important factor in the development of some mental health conditions, such as schizophrenia, bipolar, and major depression. Bipolar, for example, is four to six times more likely to develop when there is a family history of the condition. However, although the importance of genetic factors cannot be denied, the development of mental illness is not entirely genetic. For example, identical twins share their genes, yet if one twin develops schizophrenia, research shows the other twin only has a 50% chance of also developing the condition. This indicates that nature, while it plays an important part, is not the only contributing factor.

Another area where researchers may place more emphasis on nature than on nurture is that of addictions. Research indicates that alcohol addiction, for example, can recur in families and that certain genes may influence how alcohol tastes and the way it affects the body.

How nurture affects mental health

Certain genetic factors may create a predisposition for a particular illness, but the probability that a person develops that illness depends in part on environment (nurture). When a genetic variant indicates the possibility of developing a mental illness, this information can be used to direct positive (nurturing) behavior in such a way that the condition may not develop or may develop with less severity.

James Fallon, a neuroscientist who discovered that he had the brain of a psychopath, has stated that he believes growing up in a nurturing and loving environment helped him become a successful adult and may have been effective at preventing him from fully developing traits of psychopathy. Similarly, the basis for addiction is not thought to be entirely genetic by most researchers. Environmental aspects, such as the habits of parents, friends, or a partner, might also be significant factors contributing to the development of an addiction. A genetic predisposition to alcohol addiction may be far more significant if one is routinely exposed to binge drinking or other forms of alcohol abuse and comes to view this as normal alcohol use.

Researchers at the University of Liverpool recently found that while a family history of mental health conditions was the second strongest predictor of mental illness, the strongest predictor was in fact life events and experiences, such as childhood bullying, abuse, or other trauma. This supports the idea that nurture plays significant role in the development of mental health issues.

Is our intelligence based on nature or nurture?
As with most human traits, intelligence is now understood to be the result of some combination of both nature and nurture. While genes have a great influence on the size and biochemistry of the brain, its full development does not usually occur until after the first 20 years of life. Also, the heredity of intelligence tends to vary between different aspects of cognition.
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Intelligence and subsequent learning also are viewed as being largely molded by the environment the person grows up in, both before and after birth.

If you are pregnant, don't drink alcohol or use other illegal drugs. Check with your doctor or pharmacist to make sure that any current drugs or supplements you are taking will not harm your baby.

It is imperative to have safe communities and schools that nurture learning and confidence for all children so that the quest can continue to promote high cognitive development in each child.

Nature vs. Nurture in Therapy

In the mental health field, some therapeutic treatments and approaches may be nature-based or nurture-based, depending on which paradigm to which they adhere. For example, an extremely nature-based approach might seek to address mental health on a biological or genetic level, while a nurture-based approach could be more likely to address a person’s learned beliefs and behaviors. Most approaches borrow from both nature and nurture-based philosophies, and many seek to address the interaction between nature and nurture.

For example, using medication to treat a mental health issue may be a primarily nature-based approach, while behavioral therapy, which stems from behaviorist psychology, addresses a person’s upbringing and conditioning and takes a nurture-based point of view. Meanwhile, therapies based on cognitive psychology may be more likely to address the effects of both nature and nurture.

During our sessions, I consider multiple factors, including how nature and nurture work together. Please contact me today to set up an appointment.