There are only two factors that affect intelligence: genes and the environment. Since then, there has been a constant tug of war between the importance of “nature or nurture”, to assess a person’s mental and physical prowess. Whereas a person may inherit a certain set of genes, what happens to him/her depends upon environmental factors. This can be reflected in the case of identical twins, where IQs (intelligence quotients) can be quite similar, but if they are raised apart, differences in levels become much wider. On the other hand, fraternal twins have less similarity; siblings raised in the same household will have IQs that are like adopted children, raised together in the same environment.
Genetic Factors
Without doubt, genes play an important part in influencing intelligence. Even before the baby is born, a mother’s age, health, nutrition, smoking, and drinking habits can greatly affect the fetus. Hereditary factors like blood type, mother’s red blood cell count, and even RH ( a protein found in red blood cells) compatibility to the baby can affect its intelligence. A mother’s history of number of pregnancies, and the time between pregnancies also come into play. Even excessive exposure to X-rays or large amounts of lead can be strikes against a baby’s intelligence.
It is believed breastfed babies rank higher on IQ tests at the age of 6, than their counterparts who drank milk from a bottle. Birth order also affects IQ. It is believed every successive sibling will rank .7 lower on their test scores. This is also reflected in scholastic achievement. However, the argument might be the oldest and youngest of siblings usually receive more parental attention, resulting in more or less motivation than middle children. Birth order appears to place a part in their intelligence development and growth.
Environmental Factors
There is no evidence that having good nutrition factors into childhood intelligence, but a prolonged period of malnutrition can affect IQ. Children who purportedly eat breakfast every day, score ten points higher on an IQ test than those who do not. This might constitute good argument for children not to go to school hungry; eat their breakfast every morning; to learn better at school.
Early years – Growing up in a spacious house and in a good neighborhood have profound effects on a child’s mental and emotional development. Parental background such as education, occupation, and family income also play a large role in the factoring of IQ.
Quality of toys, books, magazines; external stimuli such as travel; going to an organized institution; even taking music or dance lessons can affect a child’s intelligence. Quality of the school does not appear to affect intelligence, but school attendance does play a major part, especially during elementary school. Stability appears to be an important portion of a child’s upbringing when it comes to intelligence.
While there are questions concerning the interplay between heredity and environment, there are also theories that categorize different kinds of intelligence. Some scientists believe in a single general ability while others claim there are many and multiple intelligences: verbal, visual, kinesthetic (muscular movement), logic, social, musical, intrapersonal (within oneself), and natural (having the ability to be at one with nature).
Age also factors into intelligence, as the very young have the ability to do abstract thinking and reasoning, without the previous experience of education or learning. At this young age, they can create strategies for problem-solving and solving puzzles as well.
However, as one ages, this kind of abstract thinking decreases after the age of 30-40. People who are older tend to think along the terms of past learning and past experience. This intelligence makes use of facts, new knowledge and cumulative understanding in order to learn. This kind of learning, reasoning, and solving problems continues throughout adulthood.
In addition, there is a new intelligence to be added to the list of multiple intelligences, and that is emotional intelligence. Emotional intelligence can be a genetic ability from birth or it can be learned or strengthened by environmental elements. In 1990, a couple of scientists/psychologists determined that emotional intelligence is an offshoot of social intelligence – having the ability to observe one’s and other people’s feelings or emotions. This is an ability to discriminate or guide one’s emotional thinking and therefore one’s actions.
Since there are many facets of intelligence, all kinds of environmental factors can affect the genetic makeup of any given individual.
