The first introduction to psychology normally comes in the kind 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 act or what illnesses they may develop. But hardly any of these students have an understandable comprehension 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 have to survive. Genes are nothing more than instructions for doing things. People, as all living things, are programmed through thousands of years of natural selection to engage in behavior that is 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, siblings, or other kin will determine such behaviour.
Concerning understanding what is going on genetically, we are 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 thousands of years. However, in the last 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’s all about the epigenome. The Epigenome is a mobile memory storage which determines whether or not 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 behaviour exists in all of us, but in varying quantities. Most of the variations come from the variation in the copies of genes inside the cellular memory storage of the person. The copy of the gene which determines the behavior is called the epigome. It is this particular copy that we call the epigenome.
The importance 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 which existed between individuals who had identical twins but whose traits were very different. This study provided the first evidence of the importance of the epigenome in human behaviour and its link to abnormal behavioral disorders such as autism.
Although the importance of the Epigenome in psychology has been established, many in the psychological field are hesitant to accept its potential as a substantial element in mental illness. One reason for this is it is hard to define an actual genetic sequence or locus that leads to a behavioral disorder. Another problem is that there are just too many genetic differences between people to use a single DNA sequence to determine mental illness. Finally, although the research on the Epigenome has been promising, more work has to be done to find out the role that genetics play in complex diseases like schizophrenia. If this finding holds true, it may be used as a foundation for studying other complex diseases that have complex genetic components.
If you are interested in knowing 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 now to better understand how Epigenetics affects behavior and the susceptibility to disease. You can even hear me speak on my epigenetics and autism blog. My research into Epigenetics is focused on understanding the ecological causes of disease, but I have also been involved in analyzing the relationship between Epigenetics and Autism. My future posts will also discuss diseases of the brain which can be affected by Epigenetics.