Biological and Psychological Systems Term Paper

Excerpt from Term Paper :

standing and intense debate as to whether human personality is determined or influenced biologically or psychologically. Those in the pro-biological (or pro-nature) side contend that a person's genes have a stronger or final say about a person's acts and destiny, while those in the psychological (or pro-nurture) side say it is the way the person is/was raised as a child and his peer interaction that determine the personality system that will evolve. Does the human personality derive from nature or from nurture? Is his learning achievement, social or moral formation, habits and viewpoints ingrained in his genes or established by the way he is brought up?

The pro-nature side holds that learning or knowledge acquisition, in particular, is in itself a kind of genetic information that is pre-determined by natural selection (Csongradi 2004). Some of the knowledge a person gains may come from interactions or functionally, but what is genetically established will also change or influence the person's experiences. What he learns about the world from the family, school, religion and society in general is something natural and only reinforced over time. This is demonstrated by studies on the pack behavior of animals that grew out of the best chances of procreation and this understanding of the world enhanced both group and individual survival (Csongradi). As in other illustrations, this animal behavior favored the survival of offspring and perpetuated genes that would guarantee that survival. Studies of highly gifted autistic patients also showed that a person can develop extraordinary artistic or scientific talents without requiring nurture.

Philosophers David Hume, Rene Descartes and Immanuel Kant and the foremost behaviorist Sigmund Freud examined the relationship between inherited/biological and learned/psychological forces in the formation of the human personality (Csongradi). Freud held that nature is a reality that must be reckoned with. Descartes yielded into agreeing that if there were real things outside the mind or beyond human thoughts, God was responsible for their interpretation. Kant moved away from Descartes by proposing that the human mind must be an active participant in the acquisition of learning and in constructing some aspects of experience. Kant also assumed that certain categories or concept forms were inherited that could organize experience.

The purely biological or natural personality system cannot, however, explain the survival of certain values or culture for which there is no pronounced natural selection pressure (Csongradi). Altruism among individuals who are un-related does not have evolutionary basis on which the purely biological or natural personality system depends.

The pro-nurture sector endorses the view that the only major role parents play in shaping a child's personality is their supplying his genes (LeDoux 1998). A child's interaction with peers and the kind of environment in which he grows up have much greater impact and these are grounded by both hard documentation and common sense. A stressful life can and does change significant aspects of the brains development and function, whereby nurture affects or alters nature.

Findings of the Human Genome Project showed that the human person has only 30,000 genes or barely twice those of a fruit fly (Davies 2001). The project was aimed at discovering what genes caused killer diseases and complex behavioral traits and, therefore could be genetically controlled. In the process, it was found out that human personality is developed more from nurture than nature, therefore, not genetically determined or influenced.

As part of the Genome Project conclusion, the defective colon cancer gene existed in each cell of some of the tested patients, but it flared up only in the gut by toxins. Project researchers came to view cancer as an environmental disease. Scandinavian researchers agreed with the Genome researchers on this view of cancer, after studying 45,000 twins. Cancer, then, is seen as a nurture consequence, not a biological one (Davies).

The Project recognizes the significance of human genes as giving rise to many related proteins, each of which plays or is capable of playing a different bodily function or role. The key to establishing the roles of genes in the environment and vice-versa lies with the so-called "snips" - about 3 million of them - litter the DNA and often vary between unrelated people. Of these 3 million snips, only around 10,000 are estimated to have functional consequences, the researchers said. These included increased risks to common diseases and conditions, such as cancer, asthma, diabetes, hypertension and Alzheimer's, some persons' reactions to particular drugs (Davies). If these risks can be identified, doctors can reduce these risks by prescribing responsive regimens and medications in order to avoid them (Davies). But this capability will also threaten one's acquiring and holding jobs, securing insurance and keeping personal information personal and private. Already, 22 states have passed genetic privacy laws because the looming threat on privacy. Researchers believed that there could be laws penalizing people for their "bad" genes, but no one should be punished for his genes.

There have been claims about the discovery of genes that control addiction, shyness, thrill seeking, and sexual orientation, but all that has only been considered media hype. Much attention has, however, been drawn to genes that code for proteins involved in transmitting electrical signals in the brain by drugs like the antidepressant Prozac (Davies) by changing the activity of neurotransmitters. This action illustrates that what is inherited in the proteins that produce those chemicals can also produce desired and dramatic effects on the person's mood, temperament and entire personality system. Despite this drive and outcome, the most stubborn researchers agreed that the environment still plays a most critical role in shaping human behavior, temperament and intelligence Davies).

A study conducted at the University of California in San Francisco revealed the intimate link between genetics and environment. Subjects with high pitch had relatives with the similar gift, meaning that a perfect pitch is genetically predetermined. But the same study showed that the subjects needed to be earlier in music before the age of six in order to manifest that gift, and that only future evidence can prove that perfect pitch is genetically predetermined.

Most studies hold that what is inherited is not a behavior (Wilderdom 2003), but how the person responds to his environment - the orientation, predisposition or tendency to behave in a certain way. Genetic influences on human behavior are polygenic, meaning that not one single gene can account for most behaviors.

Delinquency, criminal lifestyle, and maladaptive criminal behavior are commonly believed to be heritable. Such behavior may be shown as extraversion depression, alcoholism, dominance, neuroticism, mania, impulsiveness and hyperactivity, and individuals with these traits have increased incidence of behavioral problems than those without these traits (Davies).

Studies conducted on adopted children to test the difference between how they were raised by adoptive parents and they biological parents raised their own. Findings revealed strong genetic effects on the criminal or delinquent behavior of adopted children (Wilderdom). They suggest that biological children of relatives with criminal or antisocial behavior have a greater history of criminal records than without. It further maintained that genetic influences on criminality and alcoholism were more violent if the biological parents were both criminal and alcoholic. No direct link, however, was established between criminality/antisocial personality and alcoholism. What these studies pointed to was the profound effect of a criminal adoptive parent on an adopted child's genetic inclination for criminality (Wilderdom). Researchers, in general, held that environmental and genetic factors in personality system development differentially influence behavior.

Other studies argued that both nature and nurture take part in, and contribute to, the development of human personality (LeDoux), although the comparative extents are not yet completely known today. Both nature and nurture alter the synaptic organization of the brain. Synapses are connection points between brain cells through which they communicate and these synapses account for most of the brain's activity. The pattern of synapses and the information these synapses input reveal the person (LeDoux).

Every baby born is already endowed with huge preprogrammed synaptic links, right from the time of crying at birth. But each experience changes synapses or creates new ones. The ability to view the world the same or other way as do others is something also already programmed in each individual, but not that world view. It is only when the right kinds of visual experiences occur can synapses in the brain allow normal personality development. Otherwise, that child's view becomes poorly aligned at a certain point of life or age, during which his brain's visual system of deprived of the input and depth and whereby his perception is impaired.

Experience, too, shapes or replaces synapses and this is referred to as "synaptic plasticity." Large volumes of synaptic plasticity occur in early childhood as the brain develops. This is also the time that learning and memory forms to shape synapses, in turn, throughout life. Memory, for its part, has been revealed to have more than one form, which is explicit, or conscious recall of past information. Recent studies revealed that an implicit or unconscious kind of memory also exists and enables…

Cite This Term Paper:

"Biological And Psychological Systems" (2004, March 21) Retrieved August 21, 2017, from

"Biological And Psychological Systems" 21 March 2004. Web.21 August. 2017. <>

"Biological And Psychological Systems", 21 March 2004, Accessed.21 August. 2017,