The first introduction to psychology normally comes in the kind 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 degree, how they act or what illnesses they might develop. But hardly any of these students have a clear comprehension of what exactly DNA is, where it is 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 need to survive. Genes are nothing more than 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 behaviour.
In terms of understanding what is happening genetically, we are still in the era of molecular biology. Within this frame, genes are simply packets of information carrying directions. This is the way humans, plants and animals have been growing for centuries. Nevertheless, in the past 50 years or so, a revolution in the field of psychology has happened known as molecular biology or genomics. Genomics offers a new lens through which we can view the relationships between behavior and genes.
The molecular basis for behaviors and human memory is in fact quite simple – it is all about the epigenome. The Epigenome is a cellular memory storage that 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 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 individual. The copy of the gene which determines the behaviour is called the epigome. It is this particular copy that we call the epigenome.
The significance of the epigenome in psychology and its relationship to individual differences was shown 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 people 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 like autism.
Even though the importance of the Epigenome in psychology has been established, many in the psychological area are hesitant to accept its potential as a significant factor in mental illness. One reason for this is 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 find out the role that genetics play in complex diseases such as schizophrenia. If this finding holds true, it may be used as a basis for studying other complicated diseases that have complicated genetic elements.
If you are interested in learning 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 also have been involved in analyzing the relationship between Epigenetics and Autism. My future posts will also talk about diseases of the mind that can be impacted by Epigenetics.