As far as how an individual personality is biologically determined, no one really knows just in what manner it is accumulated. In an article conducted by John Hockett, he describes the differences as such; “Nature is a trait which does not change with age, while nurture is an influence, uncorrelated with nature and making for individual differences which change with the length over time or number of years through which it acts”. In other words, nature is permanent and nurture causes it to fluctuate (Hockett). Early childhood experiences are often linked with personality changes in people. This goes along with theories that maybe personality is only determined from your own experiences after you’re born. Many people also believe that personality is pre-determined by your biological make-up even before you are born. The truth in the matter is that your personality is made up by a combination of both nature(Biological Genotype) and nurture (your personal life experiences).
There are many problems involving the nature vs. nurture debate. The idea that peoples personality/disition making is strictly biological at birth and cannot be changed throughout their life could be used to argue that people charged with major crimes should not be given the chance to be rehabilitated. This would be because we believe that people cannot change their moral being, even if put through helpful services. For people who believe that nurture (or your environment you are in growing up) is the only factors for personality development would have to argue that you are not born with your personality, that it is created from your own life expirience. This conclusion would make it very hard to show hereditary links between personality and mood disorders in family trees.
I personally have heard of studies that show that there is a correlation between the two (nature & nurture theories) In present day, most psychiatrists can agree that personality is shown in early
Cited: Plomin, R. (1994). Nature, nurture, and social development. Social Development, 3(1), 37-53. doi: http://dx.doi.org/10.1111/j.1467-9507.1994.tb00022.x Symonds, P. M. (1926). Nature vs. nurture. Journal of Educational Psychology, 17(7), 498-500. doi: http://dx.doi.org/10.1037/h0067291