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 know that their genes determine how their bodies work, how they function and, to a certain extent, how they behave or what illnesses they may 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 changed.
In the case of development, the genes passed from one generation to the next just need 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 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 are still in the age of molecular biology. In this framework, genes are simply packets of information carrying instructions. This is the way humans, plants and animals have been evolving 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 can view the relationships between behavior and genes.
The molecular basis for human and behaviors memory is actually quite simple – it is all about the epigenome. The Epigenome is a cellular memory storage which determines whether 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 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 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 discovered that there was substantial heritability (hitability) to behavior which existed between people who had identical twins but whose traits were quite different. This study provided the first evidence of the significance of the epigenome in human behaviour and its connection to abnormal behavioral disorders such as autism.
Although the importance of this Epigenome in psychology was established, many in the psychological field are hesitant to accept its potential as a substantial element in mental illness. 1 reason for this is that it is difficult to define a real genetic sequence or locus that leads to 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 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 basis for studying other complex diseases that have complicated genetic elements.
If you’re 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 even 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 analyzing the relationship between Epigenetics and Autism. My future posts will also talk about diseases of the brain that can be affected by Epigenetics.