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 know 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 an understandable 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 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 basis 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, grandparents, or other kin will determine such behavior.
Concerning understanding what is happening genetically, we are still in the era of molecular biology. In this frame, genes are simply packets of information carrying instructions. This is how humans, plants and animals have been evolving for centuries. Nevertheless, in the past 50 years or so, a revolution in the field of psychology has occurred known as molecular biology or genomics. Genomics offers a new lens through which we can see the relationships between behavior and genes.
The molecular basis for human and behaviors memory is in fact quite simple – it is 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. Most 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 that determines the behaviour is known as the epigome. It is this particular 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 that existed between people who had identical twins but whose traits were quite different. This study provided the first evidence of the importance of the epigenome in human behaviour and its connection to abnormal behavioral disorders such as autism.
Although the significance of this Epigenome in psychology was established, many in the emotional area are hesitant to accept its potential as a substantial factor in mental illness. 1 reason for this is that it is difficult to define an actual genetic sequence or locus that causes a behavioral disorder. Another problem is that there are simply too many genetic differences between people 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 like schizophrenia. If this finding holds true, it can be utilised as a basis for studying 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 today 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 focused on understanding the environmental 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 mind which can be affected by Epigenetics.