The first introduction to psychology usually 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 function and, to a certain degree, how they act or what illnesses they may develop. But hardly any of these students have a clear comprehension 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 need to survive. Genes are merely instructions for doing things. Humans, as all living things, are programmed through thousands of years of natural selection to participate in behavior that’s 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, grandparents, or other kin will determine such behavior.
Concerning understanding what is happening genetically, we are still in the era of molecular biology. Within this framework, genes are simply packets of information carrying instructions. 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 occurred known as molecular biology or genomics. Genomics provides a new lens through which we can 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 amounts. The majority of the variations come from the variation in the copies of genes inside the cellular memory storage of the person. The copy of the gene which determines the behaviour is known as the epigome. It is this specific copy that we call the epigenome.
The importance 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 found that there was substantial heritability (hitability) to behavior that 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.
Although the importance of this Epigenome in psychology was established, many in the emotional field are hesitant to accept its potential as a substantial factor in mental illness. One reason for this is it is hard to define a real genetic sequence or locus that leads to 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 study 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 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 strongly advise that you follow the links below. My website 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 ecological causes of disease, but I also have been involved in studying the relationship between Epigenetics and Autism. My future articles will also discuss diseases of the mind that can be affected by Epigenetics.