The first introduction to psychology usually comes in the kind of biology classes. Many biology students already come into class with at least basic understanding 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 hardly any of these students have a clear comprehension of what exactly DNA is, where it’s found in the body, why it causes problems, and how it can be manipulated or changed.
In the case of development, the genes passed from one generation to the next only have 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’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’re still in the age of molecular biology. In this framework, genes are just packets of information carrying directions. This is how humans, plants and animals have been growing 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 behavior and genes.
The molecular basis for behaviors and human memory is actually quite simple – it is 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 behavior exists in all of us, but in varying quantities. The majority of the variations come from the variation in the copies of genes inside the mobile memory storage of the person. The copy of the gene which determines the behavior is called the epigome. It’s this specific 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 years, autism research was based upon research on twins. However, it was discovered that there was substantial heritability (hitability) to behavior which 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 behaviour and its link to abnormal behavioral disorders like autism.
Even though the importance of the Epigenome in psychology has been established, many in the psychological field are hesitant to accept its potential as a significant element in mental illness. 1 reason for this is it is hard to define an actual genetic sequence or locus that causes 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 research 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 can be used as a foundation for studying other complex diseases that have complex genetic components.
If you’re interested in knowing more about Epigenetics and how it applies to psychology, I highly recommend that you follow the links below. My site discusses the exciting new technologies that are available today 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 impacted by Epigenetics.