The first introduction to psychology usually 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 degree, 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 only have to survive. Genes are merely instructions for doing things. People, as all living things, are programmed through thousands of years of natural selection to participate in behavior that is survival oriented. The foundation for this programming is that 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 behaviour.
In terms of understanding what is going on genetically, we’re still in the age of molecular biology. In this framework, genes are simply packets of information carrying instructions. This is how humans, plants and animals have been growing 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 behaviour and genes.
The molecular basis for behaviors and human memory is actually 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 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 behavior 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 behavior is known as 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 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 significance of the epigenome in human behavior and its connection to abnormal behavioral disorders like autism.
Although the importance of this Epigenome in psychology was established, many in the emotional field are reluctant to accept its potential as a substantial factor 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 issue 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 can be used as a foundation for studying other complex diseases that have complex 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 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 that can be affected by Epigenetics.