The first introduction to psychology usually 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 degree, how they act 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 development, the genes passed from one generation to the next just need to survive. Genes are merely instructions for doing things. People, as all living things, are programmed through thousands of years of natural selection to engage in behavior that’s survival oriented. The foundation for this programming is 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, siblings, or other kin will determine such behavior.
In terms of understanding what is going on genetically, we are still in the age of molecular biology. Within this frame, genes are simply packets of information carrying directions. This is the way humans, plants and animals have been evolving for thousands of years. Nevertheless, in the past 50 years or so, a revolution in the field of psychology has happened known as molecular biology or genomics. Genomics provides a new lens through which we could see the relationships between behaviour and genes.
The molecular basis for human and behaviors memory is in fact quite simple – it is all about the epigenome. The Epigenome is a mobile memory storage that determines whether a behavior will be expressed 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 amounts. Most of the variations come from the variation in the copies of genes within the mobile memory storage of the individual. 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 was revealed 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 significance of the epigenome in human behavior and its link to abnormal behavioral disorders such as autism.
Even though the significance of the Epigenome in psychology was established, many in the psychological field are reluctant to accept its potential as a significant factor in mental illness. One reason for this is that it is hard to define an actual genetic sequence or locus that leads to a behavioral disorder. Another issue is that there are just 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 find out the role that genetics play in complex diseases such as schizophrenia. If this finding holds true, it may be utilised as a foundation for studying other complicated diseases that have complex genetic elements.
If you are interested in learning more about Epigenetics and how it applies to psychology, I strongly advise that you follow the links below. My website discusses the exciting new technologies that are available today 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 centered on understanding the environmental causes of disease, but I have also been involved in studying the relationship between Epigenetics and Autism. My future posts will also talk about diseases of the mind that can be affected by Epigenetics.