TWINS AND THE NATURE-NURTURE OF INTELLIGENCE: Intelligence is defined by psychologists as “the ability to reason, plan, solve problems, think abstractly, comprehend complex ideas, learn quickly and learn from experience” (Dr. C. George Boeree 2003). It is an interesting aspect of the human being that psychologists try to understand in terms of the various factors that influence it. The variation in the level of intelligence in human beings is scored using the IQ. It is evaluated across a spectrum of perspectives ranging from biological, psychoanalysis, cognitive psychology, humanism and behaviorism. But the most debated is how nature and nurture influence intelligence. Nature follows with a biological approach focusing on genetic, hormonal and neuro-chemical explanations of behavior that are acquired, while nurture focuses on all behavior learnt from the environment through conditioning. “Nature is what we think of as pre-wiring and is influenced by genetic inheritance and other biological factors. Nurture is generally taken as the influence of external factors after conception e.g. the product of exposure, experience and learning on an individual” (Saul McLeod , 2007). How nature or nurture influence intelligence or which of them is more influential, is highly studied psychologists. Such studies have been attempted by using twins by isolating from their siblings, and evaluating whether genetic or environmental factors has influence on their intelligence. In their use, identical (monozygote) twins are separated and made to grow in different environmental conditions such as socioeconomic status, parents’ behavior, alcoholism, criminal behavior, emotional adaptation and nutrition while non-identical twins are used as controls. This is done by testing their IQ. (Nature vs Nurture in Intelligence, 2005) The influence of nature on genetic is easily studied using heritability or traits that are considered inherited, including intelligence. Psychologists try to compare the influence of heritability and the environment by taking advantage of the idea that monozygotic twins share 100 percent of their genes while dizygotic twins share 50 percent. Consequently identical twins are expected to display the same
1. Some people have argued that the Johns Hopkins psychologist used this opportunity as an experiment to test his nurture theory of gender identity. What are the expected results of this experiment, assuming that the nurture theory is valid?
Many psychologists agree that nurture play a greater part in the development of a human being. Studies such as those performed on monozygotic twins (identical), who share the same genetics and those performed
“Trying to separate out nature and nurture as explanations for behavior, as in classic genetic studies of twins and families, is now said to be both impossible and unproductive” (Levitt, 1). Social scientists have declared the nature-nurture debate to be unnecessary. Similarly, scientists feel that such debate is not only unhelpful, but also outdated. From geneticists’ perspective, nurture and nature interact to influence
The debate on nature versus nurture is an old philosophical issue in psychology. Nature involves all genes as well as hereditary factors, which influence who we are. These range from the physical appearance to the personality features of a person. Nurture involves all environmental variables, which determine who we are: experiences during early childhood, how one is raised, the surrounding culture, and one’s social relationships. Biological psychology today insists on the significance of genet is as well as biological influences. When it comes to behavioral psychology, the most important thing is how the environment affects behavior. Unlike earlier when debates on relative contributions of the concept took a one-sided approach, experts currently
The brain is one of the most complex, unknown organs of the human body. Researchers often break down the characteristics of the brain to whether tendencies are achieved through nurtured environments or the inheritability of genetics. Intelligence is one of the most controversial topics when it comes to deciding whether environment or genetics are most influential. Many argue that intelligence is based on environmental factors and the unique ability to work hard, but fail to realize the essential cognitive qualities concerning what truly defines intelligence. Although some may consider this trait as based on environment, intelligence is a cognitive attribute established by the nature of genetics.
Susan Evers and Sharon McKendrick, the famous identical twins from the movie The Parent Trap, were separated at a young age by their divorcing parents. Sharon grew up in Boston to a socialite mother while Susan grew up in California on her father’s ranch. Sharon had structure while Susan’s life was very laid back. They looked the same and liked many of the same things, yet their personalities were very different. What is responsible for these differences? Is it simply that they are two different people with different interests and preferences? Or did the environments that they grew up in play a part in making who they are? In the nature vs. nurture controversy, nature proclaims that our genetic make-up plays the primary role in human
The nature side of the argument is basically what we are born with, our heredity. The main idea of this is that we are born with predetermined traits that may or may not create psychopathic tendencies in us. Dr. Richard Davidson of the University of Wisconsin at Madison published a report in 2000 that compared brain scans of five
For many years, there has been on the ongoing debate that is referred to as nature vs. nurture. It poses a question that many theorists have contested. Do human personalities and behaviors relate to our genetic makeup, or are we directly influenced by the environment and people that we are subjected to? What is more important, genes or environment? While some theorists take either one side over the other, some believe that both nature and nurture play an active role in human development.
‘Heritability’ refers to how far genetic differences are responsible for variations in traits, characteristics or abilities within a population. Heritability studies may involve twins or adopted children, where it might be possible to distinguish between genetics and environmental influence. These studies generally find that monozygotic twins are more intellectually akin than dizygotic twins; similarly children who have been adopted, remain intellectually comparable with their biological parents. This infers that there must be a genetic component responsible for differences in intelligence. However heritability estimates are inconclusive. (Deary 2001) claims that the heritability estimate tends to be placed between 40% and
A debate on Nature versus Nnurture has been going on for a long time. In this essay I will describe my views on the subject. To examine them side by side we will explore how they both affect intelligence. The Pearson Custom Library Psychology defines nature as “the influence of heredity or genes… (P. 342)” and Nnurture as the “environment (P. 342 Ciccarelli)” affecting one’s personality or intelligence. In other words, how is someone’s environment affecting their mental development compare to their genes?
Over the years, scientists have struggled to prove whether nature or nurture has the key role in the determination of key characteristics and traits that humans have expressed. One characteristic’s development that has been extremely difficult to base solely off of genetic of environmental influence is a human’s intelligence. The question of whether a person’s intelligence comes from the generations before them or does it simply develop from life experiences, lessons, and schooling. The tumultuous amounts of research and ever-changing and advancing theories all seem to agree that both nature and nurture have a partial role in the development of intelligence.
A child is born with many traits, but the environment they grow up in effects that. No child is exactly born dishonest or kind. Parenting styles and their type of punishment play a role in a child’s social behavior. Urie Bronfenbrenner argued with his ecological-systems approach that a person is affected by the systems around them such as school, economic patterns, and peers. If a child has permissive parents the child may think that yelling or stealing from others is acceptable because their parents never enforced rules at home, and then they carry that with them as they grow up. In Kathleen Berger’s textbook “Developing Person Through Childhood and Adolescence Eighth Edition” a study showed that “boys who were mistreated by their parents
As mentioned briefly in my self-introduction post, the nature-nurture portion of our textbook is the one part of this course I stated I looked forward to the most. I have always found myself engaged in a constant internal battle regarding nature versus nurture. Adding to this internal battle is the fact that I am married to an identical twin…a twin who drastically differs from his brother in several ways. These differences between my husband and his twin have resulted in my questioning if the gene + environment additive or the gene + environment interaction was at play. Thus, I find myself stuck in the middle of this often-heated debate, going back and forth between both nature and nurture.
which they act. In the same way, the effects of the environment dependents on genes on with which they work .for-example people are very in height, although height is heritable but the environmental variable can have the large impact to it. An aspect of human intelligence and behavior have involved studies of twins, both monozygotic (identical) and (dizygotic (fraternal); cognitive or behavioral characteristics that entirely under the genetic control would be predicted to be the same or concordant, in monozygotic twins who share in identical.
While this assumption is accepted by a majority of geneticists and behavioral scientists, there is great disagreement on the degree of influence each contributes. Arguments for environmental influences are compelling; at the same time there is growing evidence that genetic influence on intelligence is significant and substantial (Eyesenck, 1998; Mackintosh, 1998; Plomin, 1994; Steen, 1996). The purpose of this paper is to explore the question: "How is intelligence influenced by heredity and environment?"