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 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 an understandable understanding 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 only have 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 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, siblings, or other kin will determine such behaviour.
Concerning understanding what is happening genetically, we’re still in the era of molecular biology. Within this frame, genes are just packets of information carrying directions. This is how humans, plants and animals have been evolving for thousands of years. Nevertheless, in the last 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 behaviors and human memory is actually quite simple – it is all about the epigenome. The Epigenome is a cellular memory storage that 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 amounts. The majority 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 that determines the behavior is known as 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 has been revealed 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 which existed between individuals who had identical twins but whose traits were quite 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 significance of the Epigenome in psychology has been established, many in the emotional area are reluctant to accept its potential as a significant factor in mental illness. One reason for this is that it is difficult 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, although the research on the Epigenome has been promising, more work needs to be done to determine the role that genetics play in complex diseases like schizophrenia. If this finding holds true, it may be utilised as a foundation for studying 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 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 studying the relationship between Epigenetics and Autism. My future posts will also talk about diseases of the brain which can be affected by Epigenetics.