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 physically function and, to a certain extent, how they behave or what illnesses they might develop. But very few of these students have an understandable understanding of what exactly DNA is, where it is 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. Humans, as all living things, are programmed through thousands of years of natural selection to engage in behavior that’s survival oriented. The basis for this programming is the expression of specific 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 are still in the age of molecular biology. In 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 last 50 years or so, a revolution in the field of psychology has occurred known as molecular biology or genomics. Genomics provides a new lens through which we could see the relationships between behavior and genes.
The molecular basis for behaviors and human memory is in fact quite simple – it is all about the epigenome. The Epigenome is a cellular memory storage which determines whether a behavior will 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 behaviour exists in all of us, but in varying quantities. Most 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 behaviour is known as the epigome. It’s this particular 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 found that there was substantial heritability (hitability) to behavior that existed between people who had identical twins but whose traits were very different. This study provided the first evidence of the importance of the epigenome in human behavior and its connection to abnormal behavioral disorders such as autism.
Even though the importance of this Epigenome in psychology has been established, many in the psychological area are reluctant to accept its potential as a significant factor in mental illness. One reason for this is that it is difficult to define an actual genetic sequence or locus that leads to a behavioral disorder. Another problem 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 such as schizophrenia. If this finding holds true, it may be used as a basis for analyzing other complicated diseases that have complicated genetic components.
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 focused 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 discuss diseases of the mind which can be impacted by Epigenetics.