The first introduction to psychology normally comes in the form of biology classes. Many biology students already come into class with at least basic understanding of psychology. They know 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 hardly any of these students have an understandable comprehension 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 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 foundation for this programming is that 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 behavior.
In terms of understanding what is happening genetically, we are still in the era of molecular biology. Within this frame, genes are simply packets of information carrying instructions. This is how humans, plants and animals have been growing 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 can 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 cellular memory storage which determines whether or not a behavior is going to 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. 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 that determines the behaviour is known as the epigome. It is this specific copy that we call the epigenome.
The importance of the epigenome in psychology and its relationship to individual differences was shown in a landmark study on twins. For 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 quite 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.
Although the importance of the Epigenome in psychology was established, many in the psychological field are hesitant to accept its potential as a substantial factor in mental illness. 1 reason for this is it is hard to define a real genetic sequence or locus that causes 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 research on the Epigenome has been promising, more work needs 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 foundation for studying other complex diseases that have complicated genetic elements.
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 also hear me speak on my epigenetics and autism blog. My research into Epigenetics is centered on understanding the ecological causes of disease, but I have also been involved in analyzing the relationship between Epigenetics and Autism. My future articles will also talk about diseases of the mind that can be affected by Epigenetics.