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 degree, how they behave or what illnesses they might develop. But very few of these students have an understandable 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 development, the genes passed from one generation to the next just need to survive. Genes are merely instructions for doing things. People, 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 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, siblings, 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 framework, genes are simply packets of information carrying instructions. This is how humans, plants and animals have been growing for thousands of years. However, in the past 50 years or so, a revolution in the field of psychology has happened 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 behaviors and human memory is in fact quite simple – it’s all about the epigenome. The Epigenome is a mobile 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 behaviour exists in all of us, but in varying quantities. Most 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 behaviour is called 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 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 that existed between individuals who had identical twins but whose traits were very different. This study provided the first evidence of the significance of the epigenome in human behaviour and its link to abnormal behavioral disorders like autism.
Although the importance of the Epigenome in psychology has been established, many in the psychological field are hesitant to accept its potential as a significant element in mental illness. 1 reason for this is that it is hard 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 individuals 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 used as a basis 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 strongly advise 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 focused on understanding the environmental causes of disease, but I have also been involved in analyzing the relationship between Epigenetics and Autism. My future posts will also talk about diseases of the mind which can be affected by Epigenetics.