The first introduction to psychology usually comes in the kind of biology classes. Many biology students already come into class with at least basic understanding of psychology. They know that their genes determine how their bodies work, how they physically 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 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 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 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 behavior.
Concerning understanding what is going on genetically, we are still in the era of molecular biology. Within this frame, genes are just packets of information carrying directions. This is the way humans, plants and animals have been evolving for centuries. 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 behaviour and genes.
The molecular basis for behaviors and human memory is actually quite simple – it’s all about the epigenome. The Epigenome is a cellular 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 amounts. Most of the variations come from the variation in the copies of genes within the cellular memory storage of the person. The copy of the gene that determines the behaviour is known as the epigome. It’s this specific copy that we call the epigenome.
The significance of the epigenome in psychology and its relationship to individual differences has been shown 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 that existed between individuals who had identical twins but whose traits were quite different. This study provided the first evidence of the importance of the epigenome in human behaviour and its link to abnormal behavioral disorders like autism.
Even though the importance of this Epigenome in psychology was established, many in the emotional area are hesitant to accept its potential as a substantial element in mental illness. 1 reason for this is it is difficult 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, although 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 like schizophrenia. If this finding holds true, it may be used as a foundation for analyzing other complicated diseases that have complicated genetic elements.
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 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 centered on understanding the environmental causes of disease, but I also have been involved in analyzing the relationship between Epigenetics and Autism. My future posts will also discuss diseases of the mind that can be impacted by Epigenetics.