The first introduction to psychology usually 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 function and, to a certain extent, 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 is 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 merely 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 foundation 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 happening genetically, we are still in the age of molecular biology. Within this framework, genes are simply packets of information carrying directions. This is how humans, plants and animals have been growing 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 provides a new lens through which we could view the relationships between behavior and genes.
The molecular basis for human and behaviors memory is actually quite simple – it’s all about the epigenome. The Epigenome is a cellular memory storage which determines whether or not a behavior will 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. 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 specific copy that we call the epigenome.
The significance 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 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 connection to abnormal behavioral disorders like autism.
Even though the importance of this Epigenome in psychology has been established, many in the psychological field are reluctant 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 leads to a behavioral disorder. Another problem 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 has to be done to find out the role that genetics play in complex diseases like schizophrenia. If this finding holds true, it can be utilised as a foundation for studying other complex diseases that have complex genetic components.
If you’re 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 now 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 centered 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 discuss diseases of the mind which can be affected by Epigenetics.