The first introduction to psychology normally comes in the kind 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 may develop. But hardly any 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 evolution, the genes passed from one generation to the next just 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 engage 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 behavior.
In terms of understanding what is going on genetically, we are still in the era of molecular biology. Within this framework, genes are simply packets of information carrying directions. This is how humans, plants and animals have been evolving for centuries. 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 behaviors and human memory is in fact quite simple – it’s all about the epigenome. The Epigenome is a cellular memory storage that 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. The majority of the variations come from the variation in the copies of genes within the cellular memory storage of the individual. The copy of the gene which determines the behaviour is called the epigome. It is this specific copy that we call the epigenome.
The significance of the epigenome in psychology and its relationship to individual differences has been shown in a landmark study on twins. For many years, autism research was based upon research on twins. However, it was discovered that there was substantial heritability (hitability) to behavior that 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 link to abnormal behavioral disorders such as autism.
Although the importance of the Epigenome in psychology has been established, many in the psychological area are hesitant to accept its potential as a significant element in mental illness. One reason for this is that it is difficult to define a real genetic sequence or locus that causes a behavioral disorder. Another issue is that there are just too many genetic differences between people to use a single DNA sequence to determine mental illness. Finally, even though the research on the Epigenome has been promising, more work needs 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 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 highly recommend 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 discuss diseases of the brain which can be affected by Epigenetics.