Intelligence
Intelligence is shaped by a combination of genetic and environmental factors, influencing cognitive abilities and learning potential. This section explores intellectual disability, highlighting the challenges individuals may face and the support systems that can enhance their development.
By the end of this section, you should know about:
- Intellectual Disability
- Heredity and Environment
- Beyond Psychometric Intelligence
- Intelligent Intelligence Testing
Let’s take a closer look at them.
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Intellectual Disability
Intellectual disability refers to significant limitations in intellectual functioning (IQ below 70) and behavioral variables (skills needed for daily living such as communication, self-care, socializing, etc.) Psychologically disabilities can range from mild to profound, with varying degrees of severity affecting daily life and independence.
While IQ scores are an important measurement, it’s also important to recognize that people with intellectual disabilities have emotional lives and deserve respect just like everyone else. They can feel the pain of rejection and thrive on love, support and inclusion in society.
Levels of Intellectual Disability
Intellectual disabilities are classified on the basis of intelligence level and variable behavior:
• Mild (IQ 50-70): About 85% of individuals with intellectual disabilities fall into this category. They are generally able to live independently, hold jobs, and have relationships.
• Moderate (IQ 35-50): These individuals typically need some assistance with daily living but are able to perform basic self-care tasks and work on reservations.
• Severe (IQ 20-35): Individuals with severe intellectual disabilities may require considerable care and supervision, but many can learn to communicate with animals and control basic functions.
The key to helping people with intellectual disabilities is to recognize their potential and provide an environment in which they can live fulfilling+
lives.
• Profound (IQ less than 20): People with severe mental retardation often need constant supervision. These people experience limitless connections and are not fully independent in their adult lives.
Causes of Intellectual Disability
The causes of intellectual disability vary, and in many cases the cause is unknown. However, some common causes include genetics, prenatal conditions and environmental factors. Approximately 30-40% have no known biological cause, especially in simple cases where families often exhibit the same psychological patterns. Many of these cases involve poor socioeconomic backgrounds, emphasizing the importance of nutrition, health care and child rearing in the prevention of intellectual disability
Other causes are more directly biological:
Intelligence: Genetic status:
- Down syndrome: Due to an extra chromosome number 21 (trisomy 21), Down syndrome causes moderate to severe intellectual disability and occurs in 1 in 800 births and is most common in children of parents who their age gave birth among them, especially mothers over 35 years of age.
- Fragile X syndrome: The second most common genetic cause This disorder is hereditary and is associated with a weak spot on the X chromosome. It especially affects men, who exhibit physical features such as large ears and long faces, and tend to be hyperactive and socially challenging.
- Phenylketonuria (PKU): A cellular disorder in which the body cannot process phenylalanine, which, if left untreated, can lead to brain damage. It is detected early through newborn screening and can be treated with special diet to prevent intellectual disabilities.
Prenatal birth and its causes:
- Birth injury: Lack of oxygen during birth can cause brain damage, resulting in intellectual disabilities.
- Fetal exposure: Exposure to harmful substances such as alcohol, drugs, or infections during pregnancy can lead to intellectual disabilities.
- Malnutrition and environmental toxins: Poor nutrition or exposure to lead and other toxic substances in childhood can also cause developmental issues.
Physiological states of the brain:
- Microcephaly: This condition causes an abnormally small head and brain, resulting in severe intellectual disabilities. Individuals may need hospital care, although they are often loving and cooperative.
- Hydrocephalus: caused by an accumulation of cerebrospinal fluid in the brain, causing compression and possible brain damage. Surgical treatment allows many affected people to live normal lives.
- Cretinism: Due to inadequate levels of thyroid hormone, usually iodine deficiency, this condition causes growth retardation and mental retardation but can be effectively treated if diagnosed early.
Diagnosing and Supporting Individuals with Intellectual Disabilities
Intellectual disability is determined by comprehensive assessments that assess cognitive abilities (through IQ tests) and adaptive behaviors. Basic interventions and customized educational programs are essential to progress individuals with intellectual disabilities to their potential.
It is important to provide an inclusive environment where people with intellectual disabilities are valued and supported. Whether through education, work programs, or social integration, they need to focus on their potential rather than limitations. Appropriate care, social support, and community acceptance significantly improve the quality of life for people with intellectual disabilities.
Heredity and Environment
Genes do play an important role in intelligence, but they don’t work everywhere. The text begins with an example from Tryon’s (1929) study of “maze-bright” and “maze-dull” rats. Initially, Tryon theorized that intelligence was innate because he bred two mice who excelled or struggled in maze learning. But later findings showed that the “shiny” mice were more motivated and less distracted by food alone. This suggests that behaviors such as motivation can be innate, but true intelligence is difficult to measure with such tests.
The text then delves into two studies to further examine genetic influences on intelligence. It shows that identical twins, who share 100% of their genes, are much more intelligent than fraternal twins, who share only 50% of their genes Interestingly, if identical twins are raised differently, their IQ is still the same, but not so much as when they are raised together. This suggests that although genetics play a major role (about 50% of variation in intelligence), environmental factors also contribute to differences.
Environmental Influences
While genetics are important, environmental factors can also have a profound effect on intelligence. Studies show that children adopted by parents of higher socioeconomic status (SES) have higher IQs. Higher SES is generally associated with better nutrition, educational opportunities, and intellectual stimulation. In contrast, children raised in low-SES neighborhoods may have fewer benefits, but children placed in more affluent neighborhoods may have greater psychological benefits
For example, children adopted from orphanages to families in a stimulating home environment had an average IQ score of 29. On the other hand, children left in orphanages averaged 29 points lost 26 IQ points.This highlights the power of the environment in cognitive development.
The Flynn effect also supports the idea that environment plays a role in intelligence. Over the last few decades, the average IQ has risen by 5 to 25 points in many countries, too rapidly to be explained by genetics alone. Higher levels of education, better nutrition and exposure to more complex environments may contribute.
Teaching Intelligence
While part of intelligence may be hereditary, it is clear that cognitive abilities can be nurtured and developed. Early childhood programs have been shown to have a positive impact on the IQ of children from disadvantaged backgrounds. In addition, cognitive training such as problem-solving exercises and formative educational experiences have been shown to improve cognitive abilities
The concept of “academic intelligence” suggests that although intelligence scores may not increase significantly, cognitive training can improve cognitive skills and enhance a child’s ability to succeed in life This suggests that intelligence is not the fully intended, can provide the right opportunity and environment.
Beyond Psychometric Intelligence
The psychoanalytic approach to intelligence focuses on measuring intelligence through tests such as IQ, but many psychologists have expanded the concept of intelligence in different ways These new approaches provide a broader understanding of human’s abilities, focusing on brain function, cognitive processes, artificial intelligence and multiple intelligences.
The Intelligent Nervous System
One line of research in intelligence research seeks to understand how the neural system contributes to cognitive ability. The researchers examined whether highly intelligent individuals had “agile” brains and processed information faster. This is often measured in terms of reaction time—the faster a person responds to a stimulus, the higher their IQ is likely to be. Moreover, brain imaging studies suggest that certain brain regions, particularly the frontal lobe and parietal cortex, are active in higher order tasks. Although these studies suggest a relationship between brain activity and intelligence, the exact nature of this relationship remains uncertain.
Intelligent Information Processing
Psychologists say that intelligent behavior is an expression of positive thinking. According to David Perkins, intelligence is influenced by three factors:
- Neural intelligence (brain speed and efficiency), .
- Experiential intelligence (knowledge and skills accumulated through experience), .
- Reflective intelligence (metacognitive skills—how well we manage our thinking).
Thinking intelligence includes breaking down problems, setting goals, tracking progress, and improving. These skills can be developed through training and experience, increasing the ability to think rationally.
Artificial Intelligence (AI)
Artificial intelligence (AI) is another way to gain insight into human intelligence. AI refers to the development of machines capable of performing tasks that require human intelligence. One notable example is IBM’s “Watson” supercomputer, which outperformed human contestants on Jeopardy. AI has also made great strides in specific areas such as chess, defeating world chess champions with programs such as “Deep Blue.” While AI is currently still a long way from mimicking human intelligence, it provides a valuable model for understanding how we perform cognitive tasks. For example, AI can mimic human decision-making and problem-solving, reflecting how our minds work.
Multiple Intelligences
The concept of multiple intelligences proposed by Howard Gardner challenges the traditional “g-factor” (general intelligence). Gardner argues that intelligence is not a single capacity but a collection of particular and unique intelligences. He comes up with eight kinds of wisdom:
Language skills: effective use of power (e.g. secretaries, lawyers).
Logical-mathematical intelligence: The ability to think and reason logically (e.g. scientists, mathematicians).
Spatial intelligence: the ability to think graphically and imagine with precision (e.g. artists, architects).
Musical talent: the ability to compose, perform and appreciate music (e.g. musicianship).
Physical Awareness: Ability to control physical movement (e.g. dancers, athletes).
Interpersonal intelligence: the ability to understand oneself (e.g. philosophers, psychologists).
Interpersonal intelligence: the ability to understand and communicate with others (e.g., teachers, politicians).
Biological intelligence: the ability to understand the natural world (e.g., biologists, environmentalists).
According to Gardner, traditional intelligence tests primarily focus on language, mathematics, and spatial abilities, which represent only a portion of all human intelligence.
According to Gardner, traditional IQ tests focus mainly on linguistic, mathematical, and spatial abilities, which represent only a part of the full spectrum of human intelligence. In fact, many schools are now incorporating Gardner’s theory to foster a wider range of skills beyond just academic intelligence.
Implications for Education
These alternative theories of intelligence have profound implications for education. By expanding the definition of intelligence, educators can recognize a broader range of talents and foster different skills in children. For example, incorporating art, music, dance, and drama into education could help students who struggle in traditional academic subjects. Schools are increasingly adopting Gardner’s framework to cultivate students’ strengths across multiple intelligences, ensuring that all forms of intelligence are recognized and nurtured.
Intelligent Intelligence Testing
Intelligence tests, as they are administered to measure intelligence, are often subject to cultural bias. Adrian Dove’s “Dove Test” (1971) was designed to be culturally insensitive to African-Americans, revealing that often standardized tests are for African-American children of European-American middle-class background , the average European-American children The fact that expectations score lower on intelligence tests is due in part to cultural differences in intelligence expectations from genetic This highlights the issue of applicability tests that may or may not be valid in different cultural groups.
Cultural and environmental influences
Intelligence is determined by both cultural factors and environmental influences, such as education and socioeconomic status, such as those from rural areas or ethnic minorities. Cultural values, such as the emphasis on emotion or logic, can influence how people perceive intelligence. For example, tests that value formal thinking may not be compatible with cultures that prioritize other intelligences, such as practical skills.
Intelligence and genetics
The argument that genetic differences explain lower IQ scores in African Americans compared to European Americans is rejected by most psychologists Studies show that intelligence is likely differences from environmental factors, such as poor educational opportunities, rather than genetic differences. In entitlement environmental Research showing improvement in IQ with placement supports view namely that the environment plays an important role
Standardized testing and its limitations
While standardized tests can provide objective assessments of academic performance, they are not always accurate predictors of job success. Exams can also fail to pick up important qualities like creativity, practical wisdom and intelligence. Furthermore, they may be exclusionary, especially for individuals who may have low test scores despite their proficiency in other areas. Critics also say the tests focus too much on passive recall and don’t measure their ability to think critically or solve real-world problems.
Cultural justice in testing
Efforts have been made to create “culturally neutral” tests to reduce the biases associated with language proficiency and cultural awareness. But no test can be completely free of cultural influences, because different cultures emphasize different intelligences. Psychologists have argued that intelligence itself is reassessed in order to better capture its variation across cultures.
Broader Implications
Ultimately, intelligence is not a fixed, immutable trait but a reflection of both natural abilities and the opportunities for learning and development. Intelligence tests are simply tools to measure certain aspects of cognitive functioning and do not define a person’s potential. Wisdom, creativity, and other qualities, such as emotional intelligence or practical skills, are just as important to success in life as raw cognitive ability. As such, intelligence testing should be viewed with caution and complemented by a broader understanding of human potential.