The first introduction to psychology normally comes in the form of biology classes. Many biology students already come into class with at least basic understanding of psychology. They understand that their genes determine how their bodies work, how they physically function and, to a certain extent, how they act or what illnesses they might 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 evolution, the genes passed from one generation to the next only have to survive. Genes are nothing more than instructions for doing things. Humans, 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 that the expression of specific 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 going on genetically, we’re still in the era of molecular biology. In this frame, genes are simply packets of information carrying directions. 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 could view the relationships between behavior and genes.
The molecular basis for human and behaviors memory is in fact 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 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 mobile memory storage of the individual. The copy of the gene that determines the behavior is known as the epigome. It’s 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 many 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 quite different. This study provided the first evidence of the importance of the epigenome in human behaviour and its link to abnormal behavioral disorders like autism.
Although the significance of the Epigenome in psychology was established, many in the emotional field are reluctant 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 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 like schizophrenia. If this finding holds true, it may be utilised as a foundation for analyzing other complex diseases that have complex 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 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 mind which can be affected by Epigenetics.