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 may develop. But very few of these students have a clear understanding 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 development, the genes passed from one generation to the next only need 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 basis for this programming is 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, grandparents, or other kin will determine such behavior.
In terms of understanding what is happening genetically, we’re still in the age of molecular biology. Within this frame, genes are just packets of information carrying instructions. This is the way humans, plants and animals have been growing for centuries. However, in the past 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 can view the relationships between behaviour and genes.
The molecular basis for behaviors and human memory is in fact quite simple – it’s all about the epigenome. The Epigenome is a mobile memory storage which determines whether 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. Most of the variations come from the variation in the copies of genes inside the cellular memory storage of the individual. The copy of the gene which 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 has been 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 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 behaviour and its connection to abnormal behavioral disorders like autism.
Although the significance of this Epigenome in psychology was established, many in the psychological field are hesitant to accept its potential as a significant element in mental illness. One reason for this is that it is hard to define a real 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, even though 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 utilised as a basis for analyzing other complex diseases that have complicated 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 site 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 also have been involved in analyzing the relationship between Epigenetics and Autism. My future articles will also talk about diseases of the brain that can be impacted by Epigenetics.