The first introduction to psychology normally comes in the form of biology classes. Many biology students already come into class with at least basic knowledge of psychology. They understand that their genes determine how their bodies work, how they function and, to a certain extent, how they behave or what illnesses they may develop. But very few of these students have an understandable understanding of what exactly DNA is, where it’s found in the body, why it causes problems, and how it can be manipulated or altered.
In the case of evolution, the genes passed from one generation to the next just need to survive. Genes are nothing more than instructions for doing things. Humans, as all living things, are programmed through thousands of years of natural selection to engage in behavior that is survival oriented. The foundation for this programming is that the expression of certain genes that cause specific traits, such as aggressiveness, violence or sexuality. In the case of psychology, the genes that are passed on to us through our parents, grandparents, or other kin will determine such behaviour.
In terms of understanding what is happening genetically, we’re still in the age of molecular biology. In this frame, genes are simply packets of information carrying directions. This is how humans, plants and animals have been evolving for centuries. However, in the past 50 years or so, a revolution in the field of psychology has occurred known as molecular biology or genomics. Genomics offers a new lens through which we can see the relationships between behaviour and genes.
The molecular basis for behaviors and human memory is actually quite simple – it is all about the epigenome. The Epigenome is a cellular memory storage which determines whether or not a behavior is going to be voiced or not. Like all memory storage systems, it contains information that is “programmed” in advance by the genome.
What we now know is that the genetic material that determines behavior exists in all of us, but in varying quantities. The majority of the variations come from the variation in the copies of genes within the cellular memory storage of the person. The copy of the gene which determines the behavior is known as the epigome. It’s this specific copy that we call the epigenome.
The significance of the epigenome in psychology and its relationship to individual differences has been shown in a landmark study on twins. For many years, autism research was based upon research on twins. However, it was discovered that there was substantial heritability (hitability) to behavior which existed between individuals who had identical twins but whose traits were quite different. This study provided the first evidence of the importance of the epigenome in human behavior and its link to abnormal behavioral disorders such as autism.
Although the significance of the Epigenome in psychology has been established, many in the psychological area are hesitant to accept its potential as a substantial element in mental illness. One reason for this is that it is hard to define a real genetic sequence or locus that leads to a behavioral disorder. Another issue is that there are simply too many genetic differences between individuals to use a single DNA sequence to determine mental illness. Finally, although the study on the Epigenome has been promising, more work has to be done to determine the role that genetics play in complex diseases like schizophrenia. If this finding holds true, it may be utilised as a basis for studying other complex diseases that have complicated genetic elements.
If you’re interested in learning more about Epigenetics and how it applies to psychology, I strongly advise that you follow the links below. My site discusses the exciting new technologies that are available now to better understand how Epigenetics affects behavior and the susceptibility to disease. You can also hear me speak on my epigenetics and autism blog. My research into Epigenetics is focused on understanding the ecological causes of disease, but I also have been involved in studying the relationship between Epigenetics and Autism. My future posts will also talk about diseases of the brain which can be impacted by Epigenetics.