A Biological Component of Personality: Temperament

A Biological Component of Personality: Temperament

Assignment Instructions

The Learning Reflection Journal is a compilation of weekly learning reflections you’ll independently write about across Weeks 2, 3, 5, 6 and 7. During each of the assigned weeks, you will write two paragraphs, each 300 words in length (i.e., 600 words total). The first paragraph will describe a topic that you found particularly interesting during that week and what made it interesting, and the second paragraph will describe something that you have observed occurring in the real world that exemplified that topic. Only one topic may be recorded in the journal for each assigned week and your observed real word occurrence must be clearly related to it.


A Biological Component of Personality: Temperament






Let’s look at how we can see this genetic impact through its effect on temperament. Just what is temperament? It refers to individual differences in behavioral inclinations that are biologically based and remain relatively stable over time. We can see these differences very easily in babies. Some are shy and slow to warm up to new situations while others are outgoing seemingly at ease and ready to explore novel situations. There are different models of temperament, but these four seem to garner the most agreement among personality theorists: activity, sociability, impulsivity, and emotionality.

A Unique Research Methodology: Twin Studies

Twin studies have long been used to link genetics to personality. Identical twins share the same genetic makeup due to the splitting of one fertilized ovum. Fraternal twins, on the other hand, who are the result of two separate eggs being fertilized at the same time, do not share any more of an identical genetic makeup than two siblings who are not twins. The Minnesota Twin Study revealed that even identical twins raised apart from each other share many of the same traits and habits. However, it has also been shown that twins raised apart from each other have less similarity of traits than those raised together. This suggests that there is an environmental influence also at work. Similarities in personality are greater in identical twins than fraternal twins.

It is important to note that twins and siblings do not necessarily experience the same upbringing. This diversity in how children in the same household experience the environment differently is called nonshared environmental variance. For example, the first born child is often treated differently than the last born child or a boy child may be treated differently than a girl. This results in a shared environment being experienced differently by each child.

Many studies have shown that schizophrenia can run in families and has a genetic link. Thus, if one has a schizophrenic parent or sibling the odds of schizophrenia rise. If one has an identical twin with the disease the odds rise even more dramatically. This correlation exists even if the twins were raised in different households. It is not clear; however, if schizophrenia is purely a genetic disease. Structural abnormalities of the brain have been found in those suffering from schizophrenia. Concordance or the probability of a match between identical twins is neither conclusive nor exclusive.

There is not much solid, noncontradictory research findings on a genetic link to homosexuality partly, due to the values and mores of society, which have served to stigmatize homosexuality. Twin studies have shown that homosexuality appears to have some biological foundation, but genes are not the whole answer. We cannot rule out the role culture and rearing may play. How can we look at homosexuality from an evolutionary perspective? Perhaps the kin selection hypothesis will give us an answer or perhaps there is some other answer that further research will yield.

Illness and Disease

Illness, environmental toxins, and drugs can all cause disturbances in our personality and behavior. Many of us have heard the expression mad as a hatter, but how many of you know that its origin is the result of hatters being poisoned by the mercury used to make the felt hats? This continual exposure to mercury led to brain damage and subsequent alterations of brain function and behavior. Even today children are still being poisoned by being exposed to lead and other toxic heavy metals. Lead is known to damage a child’s nervous system and impair both cognitive and behavioral function. This can translate into personality problems such as antisocial behavior. There are known personality changes associated with both illegal drugs such as cocaine and prescription drugs such as thyroid medications.

Diseases can also impact our personality and subsequent behavior. It is known that Vincent Van Gogh suffered from Meniere’s disease. This disease is an inner ear disorder whose symptoms include:

  • dizziness
  • nausea
  • disturbance in hearing

Alzheimer’s disease is a disease that mainly affects older persons. It is characterized by memory loss and behavioral changes. As the disease progresses profound personality changes are present right up to the loss of the personality itself. Strokes can also initiate serious changes in personality. Depending on the region of the brain that is damaged noted changes can be increased or decreased aggression and uncooperative behavior.


Biology and Environment Interactions

Biology can affect the environments we live in. A perfect example is a baby who continually cries and is difficult to soothe. Before very long the parents become increasingly frustrated and irritated. This leads to the infant now living in an environment of exasperation and vexation. This type of environment then influences our personality. The process is repeated with certain characteristics of temperament inclining us to particular experiences which will help shape our personality. This tendency to seek out certain types of environments is called tropism. We are either moving in the direction of health-promoting or health-threatening environs.

Does how we look uncover our personality? W.H. Sheldon expanded on the work of Ernst Kretschmer, a German psychiatrist who pondered if there was an association between physique and mental maladies. Sheldon measured people’s physical ratios and came up with a theory about how underlying physiological body type was related to the types of experiences we choose. His body types or somatotypes as he labeled them are endomorphs, ectomorphs, and mesomorphs.

The way other people react to how we look has a great influence on how we view ourselves. There has been much research done on correlating beauty with goodness, smartness, and kindness. This idea then influences how people treat us which in turn shapes our worldview and our personality.

Evolution of Social Behavior

Sociobiologists study the function of the evolution of social behavior. The attachment of a child to its primary caregiver is an example of a biologically based social behavior. Sociobiological analyses are most often applied to human aggression, mating rituals, and family interactions. The motivation to give preferential treatment to one’s own children over-step or adopted children is motivated by self-interest and the desire to enhance and preserve one’s own genetic matter. This is termed by sociobiologists as the Cinderella Effect.

Over time there has been much misuse and misinterpretation of knowledge in regard to genetics. One of the most misunderstood concepts is Charles Darwin’s idea about the survival of the fittest. Simply stated it proposes that the fittest individuals evolve and reproduce and those who are less able to compete well in their environment will be less likely to grow up and reproduce. It does not mean that weaker individuals and cultures should not survive. This idea of Social Darwinism prompted American immigration laws to exclude so-called inferior groups, the Nazi dream of a master race which led to genocide, and eugenics and the forced sterilization of different groups.

The Human Genome Project is an effort to isolate all of the genes in our chromosomes. What if we succeed in doing so? What implications does this have for our future? Do we stop genetic tinkering after we have neutralized or eliminated some undesirable genetic problems as we have discussed? Or do we resurrect the idea of genetic purity and a master race?

The Behaviorist and Operant Conditioning

What is a behaviorist or learning approach to personality? Let’s look at the behaviorist approach first. Unlike Freud’s psychoanalytic approach to personality, which concerns itself with thinking and emotion, the behaviorist is primarily interested in observable behaviors which are linked to a stimulus. It posits that behaviors are learned through the application of positive and negative reinforcers.

The foundation of behaviorist thought was laid down by Ivan Pavlov, who discovered the principle of classical conditioning, which pairs an unconditioned stimulus and response with a neutral stimulus so that the conditioned stimulus will elicit a conditioned response. Other terms commonly used are generalization, discrimination, and extinction. In more modern terms we can say that many of our reaction patterns are the result of classical conditioning. Our likes and dislikes are often the result of positive or negative pairings of stimuli. These factors also help us to clarify some emotional qualities of personality. Some behavioral responses can be conditioned. It does not answer some more complex dimensions such as neuroticism.

John Watson is considered the father of the behaviorist approach. He advanced several views such as that psychology should be studied scientifically by observing behavior. He argued that no matter how complex a behavior is, it can eventually be reduced to stimulus and response and the environment determines behavior. He applied conditioning to condition fear of furry objects in an eleven-month-old baby named Little Albert. This was a demonstration in humans of Pavlov’s theory of conditioning in animals. He also developed the process of systematic desensitization. This process gradually extinguishes a phobia by presenting the feared object in small steps until the fear response is ended.

Classical Conditioning

B.F. Skinner was a psychologist whose views were a bit less rigid than those of Watson. He believed that while we had a mind it was more useful to study observable behavior than the internal workings of mental events. He felt that classical conditioning was too one-dimensional to give a complete explanation of human behavior and that one needed to sift out the causes of an act and its consequences. He called this operant conditioning. Operant conditioning is about consequences. By that, it is meant positive versus negative reinforcement and negative reinforcement versus punishment. He developed various schedules of reinforcement in order to demonstrate the success rate of the different levels of contingencies. His schedules are continuous versus partial reinforcement, ratio versus interval schedules and fixed versus variable schedules. We still see these principles being used today in so-called token economies in treatment centers and school for children and adults with certain mental disabilities.

Skinner wrote a novel entitled Walden Two which describes a utopian community of a behaviorally planned society in which the principles of operant conditioning are applied. There is only positive reinforcement and all people live in contentment. His later book Beyond Freedom and Dignity reinforced these ideas. Skinner was a determinist, which means that he believed all behavior was caused. He believed that physical factors enhanced or hindered the organism’s ability to learn in response to reinforcers. He did not believe that people had a free will and while he acknowledged emotions, he felt them to be irrelevant in the study of behavior.

Other approaches in opposition to the idea that behavior is strictly a response to environmental factors take into account the person’s state of being. For example, whether the person is tired or hungry would be taken into account while trying to explain the observed behavior.

To view a video overview of the role that behavioralism and operant conditioning have played in the field of psychology and our understanding of what might be construed as personality, click here.

Other Learning Theorists

Clark Hull was interested in the nature of habits. These are simple associations in learning theory between stimulus and response. He concerned himself with the primary drives such as hunger and thirst and he turned his attention to the internal condition of the subject during learning while also acknowledging environmental factors.

The social learning theory proposed by Dollard and Miller concerns itself with a hierarchy of acquired drives. This theory posits that this is how habits are built. Say, you were attracted to a guy or gal who was physically very attractive and you went out on a date with him. During the date, the person became very physically aggressive with you and you were assaulted. According to this theory, you now have learned to avoid very good looking people and actually become anxious in their presence. This acquired drive of anxiety may force you to learn a new behavior such as dating very attractive people only if it is a double date with someone you know is not dangerous. This learned secondary drive is a habit hierarchy or particular responses in particular situations. According to this theory, mental illness can be explained as approach avoidance conflict, approach conflict, and avoidance avoidance conflict. Finally, we come to the frustration aggression hypothesis which states that aggression is the result of thwarting a person’s ability to attain a goal.



In summary, biological and learning approaches brought a degree of empiricism to the study of personality that heretofore had not been used by early theorists in the field. This emphasis on observable and measurable phenomenon has yielded important discoveries with regard to how individuals develop across the lifespan. In addition, because these approaches place a premium on hypotheses being testable, as opposed to early theorists in the field, new hypotheses and theories in these areas can be proven or disproven and, as such, the field can advance accordingly and avoid being stuck with ideas that haven’t been proven to have real utility.

Personality Theory

           The social learning theorists observed that the complexity of human behavior cannot easily be explained by traditional behavioral theories.  Bandura recognized that people learn a great deal from watching other people and seeing the rewards and/or punishments that other people receive.  Social learning theorists do not deny the influence of reinforcement and punishment, but rather, they suggest that it can be experienced through observation and does not require direct, personal experience as Skinner would argue.  In addition, observational learning requires cognition, something that radical behaviorists consider outside the realm of psychological research, since cognition cannot be observed.  Bandura took a broad theoretical perspective on social learning, whereas Rotter and Mischel focused more closely on specific cognitive aspects of social learning and behavior.

           It is also important to point out an artificial distinction that is difficult to avoid in the chapters of this section.  Chapters 10, 11, and 12 are roughly set up as chapters on radical behaviorism and formal learning theory, followed by social learning, and then concluding with cognitive theories on personality development.  However, as will be evident, the chapters overlap a great deal.  For example, Dollard and Miller’s attempt to find a middle ground between Freud and Skinner led to their initial descriptions of social learning, which provided a prelude to this chapter.  Bandura, Rotter, and Mischel address a number of aspects of cognition in their theories, but they are not as completely focused on cognition as are Kelly, Beck, and Ellis, hence the separation of this chapter from the following one.  In Social Learning Theory, Bandura had this to say:

           A valid criticism of extreme behaviorism is that, in a vigorous effort to avoid spurious inner causes, it has neglected determinants of behavior arising from cognitive functioning…

Because some of the inner causes invoked by theorists over the years have been ill-founded does not justify excluding all internal determinants from scientific inquiry…such studies reveal that people learn and retain behavior much better by using cognitive aids that they generate than by reinforced repetitive performance…A theory that denies that thoughts can regulate actions does not lend itself readily to the explanation of complex human behavior. (pg. 10; Bandura, 1977).