Nature Versus Nurture Summary
A commonly asked question amongst philosophers and psychologists throughout many centuries is “how do we come to be as individuals?” The answer seems to boil down to two plausible explanations, either personality is taught or inherited. This paper will cover the biological argument, the environmental argument and where the debate has begun to conclude with the present state of psychology. It is important to discover how humans become the way they are to be able to help better understand the cause and effect of mental and behavioural disorders to better treat and prevent them.
Nature refers to the biological processes that shape an individual through genetics. The dated argument for nature is that personality is set from early on and is difficult to change later. Research has been done to attempt to decipher whether genetics or environment is more vital for development. Twin studies help uncover this through analysing variances between identical (monozygotic) and fraternal (dizygotic) twins. Rather than personality being the result of “genetic destiny”, it has been found that having certain genes may increase or decrease the possibility of an outcome (Stangor, 2014). It was established in a recent twin studies meta-analysis that all traits are heritable to varying degrees. Heritability shines through with identical twins as they share the same DNA, making these twins – even when adopted separately – extremely similar. Though unexpectedly, in some cases they vary which directs attention of researchers to environmental factors (Polderman et al. , 2015).
Nurture refers to environmental and cultural factors that form personality throughout one’s life. Those who argued for nurture in the past believe that personality is formed by one’s environment and upbringing (Stangor, 2014). The variance between twins could be a result of individual environmental experiences. Surprisingly, the variance in twin studies shows little correlation with parental influence. What seems to be causing the variance is non-shared environment, experiences that one party may encounter that the other does not (Bartlow, 2019). Environment has been shown to impact development in many ways, an example of this is frequent and proximal exposure to violence. Researchers have found that people exposed to violence regularly throughout their upbringing can have problems with trust, combative defense in normal situations and more behavioural problems. They also note physical changes such as elevated heart rate, lung functioning decrease and sleep disruption (McCoy, 2013). This indicates that environment and genetics are both important for development, leading the debate to another possible explanation.
Recent findings suggest that important developmental factors are rooted in epigenetics; this refers to nurture forming nature – that environmental factors can trigger changes within brain cells (Powledge, 2011). Relating to the example of violent upbringings, researchers have found that particularly early exposure to violence increases certain stress hormones which may change the development of the brain's structure, connectivity and functioning (McCoy, 2013). Another finding shows that within a group of people who possess genes related to specific health conditions, that those in the group who live in lower socioeconomical positions are more likely to develop these conditions than their opposition due to an overall stressful environment (Johnson, Turkheimer, Gottesman & Bouchard, 2010). Genetics and environment seem to interact through culture as well, a correlation can be found between Western and Asian cultures. Western cultures are generally quite individualistic, where there is a lot of fixation on being autonomous. Whereas Asian countries tend to be more collectivistic, defining self by their relationships and mutual obligations. It was found that it was more common for people of collectivistic cultures to have DNA that makes them more socially sensitive than the people of individualistic cultures. The question arises as to whether culture forms DNA to fit within society, or if this trait has been passed down through generations by means of natural selection (May & Lieberman, 2010).
In the present, there is still much that is unknown about the relationship between genetics and environment. Science and research have advanced enough to determine that genetics and environment do not oppose or overpower one another, but rather work harmoniously to develop personality. There has been much focus on studying and observing environmental factors, but little is known about how genes work. To fully comprehend how genes and environment work together, science needs to advance to understand both equally (Bartlow, 2019). A further understanding on development of humans can help cultivate new information to prevent, reduce and treat many mental issues ranging from trauma, mental illness, behavioural disorders to reforming social services such as adoption centres and foster care. Establishing a deeper awareness of how nature works with nurture has the potential to do great things for society and future generations.
