Theory of Intelligence | Psychology for UPSC Optional (Notes) PDF Download

What Is Intelligence?

• Intelligence is a simple word, but its definition has been widely debated in psychology.
• Various definitions of intelligence exist, including higher-level abilities like abstract reasoning, problem-solving, and decision-making.
• Intelligence can also encompass the ability to learn, emotional knowledge, creativity, and effective adaptation to the environment.
• Psychologist Robert Sternberg defined intelligence as the mental abilities required for adapting to, shaping, and selecting any environmental context (1997, p. 1).

History Of Intelligence

• The study of human intelligence began in the late 1800s, with Sir Francis Galton as one of the early researchers in this area.
• Galton aimed to understand gifted individuals and created a lab to measure reaction times and physical traits to explore the idea that intelligence is a general mental ability shaped by biological evolution.
• He believed that quickness and other physical attributes could serve as indicators of general mental ability.
• Galton operationalized intelligence as reaction time, a key step in research to make an unmeasurable concept measurable.
• His work laid the foundation for future research and debates on intelligence, particularly regarding its heritability.

Theories Of Intelligence

• There is a debate among researchers regarding intelligence, with some seeing it as a general ability and others viewing it as a collection of specific skills and talents.
• Psychologists are divided on the genetic and environmental influences on intelligence, with some suggesting it is genetic and others emphasizing environmental factors.
• To address these varying perspectives, psychologists have developed different theories of intelligence and created individual tests to measure it.

Spearman’s General Intelligence (g)

• General intelligence, or the g factor, is a broad mental ability that Charles Spearman believed underlies various specific skills like verbal, spatial, numerical, and mechanical abilities.
• In 1904, Charles Spearman introduced the two-factor theory of intelligence.
• He used factor analysis, a technique that examines correlations between related variables to identify an underlying factor.
• Spearman observed that individuals excelling in one area of intelligence (e.g., math) tended to excel in others (e.g., music).
• He attributed this correlation to a central factor, general intelligence (g).
• Spearman proposed that there is a single g-factor representing an individual's general intelligence and a second factor, s, indicating specific abilities in particular areas.
• These two factors together form Spearman's two-factor theory of intelligence.

Thurstone’s Primary Mental Abilities

• Thurstone (1938) challenged the concept of a single g-factor for intelligence.
• He analyzed data from 56 mental ability tests and identified several primary mental abilities that together constitute intelligence, rather than a single general factor.
• Thurstone's model includes seven primary mental abilities: verbal comprehension, verbal fluency, number facility, spatial visualization, perceptual speed, memory, and inductive reasoning.
• While Thurstone didn't entirely reject the idea of general intelligence proposed by Spearman, he believed that intelligence encompasses both a general ability and multiple specific abilities.
  
• Thurstone's work paved the way for further research into the various facets of intelligence.

Gardner’s Multiple Intelligences

• Howard Gardner, following Thurstone's work, proposed the idea of multiple intelligences, rejecting the notion of a single intelligence.
• Gardner introduced the concept that distinct, independent intelligences exist, each related to specific skills and talents in different domains.
• Initially, Gardner identified seven multiple intelligences: linguistic, logical-mathematical, spatial, musical, bodily-kinesthetic, interpersonal, and intrapersonal. He later added naturalist intelligence.
• Gardner suggests that most activities involve a combination of these multiple intelligences, enhancing our understanding of concepts like creativity and leadership.
• However, this theory has faced criticism due to limited empirical studies supporting it and its omission of other potential types of intelligence beyond Gardner's list, as pointed out by Sternberg (2003).

Triarchic Theory of Intelligence

• In 1985, Robert Sternberg introduced a three-category theory of intelligence as an alternative to Gardner's theory, aiming to address its limitations.
• Sternberg's theory defines intelligence as the ability to achieve success based on personal standards and sociocultural context.
• The triarchic theory of intelligence consists of three aspects: analytical, creative, and practical intelligence.
• Analytical intelligence, also known as componential intelligence, involves problem analysis, evaluation, and finding solutions, which traditional IQ tests measure.
• Creative intelligence pertains to generating novel and interesting ideas, relying on imagination, innovation, and problem-solving.
• Practical intelligence is the ability to effectively solve everyday problems by aligning oneself with the demands of the environment, which can involve adapting, shaping, or selecting different environments.

Other Types Of Intelligence

• Different theories propose diverse perspectives on intelligence.
• Spearman suggests that intelligence is a general ability applicable in various life domains.
• Thurstone, Gardner, and Sternberg argue that intelligence consists of multiple distinct forms or branches, each representing specific skills.
• These varying viewpoints add complexity to the concept of intelligence, with each theory highlighting different facets.
• Additionally, there are more types of intelligence to consider, further enriching the discussion.

Emotional Intelligence

• Emotional Intelligence (EI) is defined as the ability to monitor and understand both one's own and others' emotions, distinguish between various emotions, label them appropriately, and use emotional information to guide thoughts and actions (Salovey and Mayer, 1990).
• EI is highly relevant in daily life, given the constant experience of emotions.
• Emotional intelligence encompasses recognizing emotional meanings and using them for reasoning and problem-solving (Mayer, Caruso, & Salovey, 1999).
• It consists of four key components:
  • self-awareness,
  • self-management,
  • social awareness, and
  • relationship management.
• High emotional intelligence entails accurately perceiving emotions in oneself and others, utilizing emotions in thinking, comprehending the reasons behind emotions, and effectively managing them (Salovey & Mayer, 1990).

Fluid vs. Crystallized Intelligence

• Raymond Cattell (1963) introduced the concepts of fluid and crystallized intelligence, which were further developed with John Horn.
• Fluid intelligence involves problem-solving in novel situations through logic and abstract thinking, without relying on prior knowledge.
• Fluid intelligence is applicable to any new problem, as it doesn't depend on specific prior knowledge.
• Fluid intelligence tends to increase with age but starts declining in the late 20s.
• Crystallized intelligence uses previously-acquired knowledge, like facts learned in school or specific skills.
• As individuals accumulate knowledge with age, crystallized intelligence increases.
• The Cattell-Horn (1966) theory posits that intelligence comprises various interacting abilities that contribute to overall individual intelligence.
• In practical situations, both fluid and crystallized intelligence can come into play. For example, while taking a math test, crystallized intelligence processes numbers and question meanings, whereas fluid intelligence helps solve novel problems.
• Fluid intelligence can potentially become crystallized intelligence over time, as novel solutions are integrated into long-term memory.
• These interactions between different forms of intelligence illustrate the dynamic nature of intelligence.

Intelligence Testing

Binet-Simon Scale

• In the early 1900s, the French government enlisted psychologist Alfred Binet to identify children who might need additional classroom assistance (Binet et al., 1912).
• Binet and his colleague Theodore Simon developed a set of questions focusing on memory and problem-solving skills.
• They standardized these questions by testing them on groups of students aged three to twelve (Binet et al., 1912).
• Binet introduced the concept of mental age, representing how well an individual's intellectual performance compares to the average performance at their age (Cherry, 2020).
• He created the Binet-Simon scale, which became the foundation for modern intelligence tests.
• The 1905 Binet-Simon scale consisted of 30 items measuring judgment, comprehension, and reasoning, considered key aspects of intelligence by Binet.

Stanford-Binet Intelligence Scale

• In the United States, Stanford psychologist Lewis Terman adapted the Binet-Simon scale to create the Stanford-Binet Intelligence Scale in 1916 (Cherry, 2020).
• The Stanford-Binet Scale assesses intelligence based on five cognitive abilities: fluid reasoning, knowledge, quantitative reasoning, visual-spatial processing, and working memory. It evaluates both verbal and nonverbal responses.
• The test provides an intelligence quotient (IQ) as a single number to represent an individual's score.
• An average score on the test is 100, with a range from 90 to 109 considered average intelligence.
• Scores from 110 to 119 fall into the High Average range, while those from 120 to 129 are considered Superior.
• Scores over 130 are classified as Very Superior.
• IQ is calculated by dividing the individual's mental age by their chronological (actual) age and then multiplying the result by 100.
• For example, if your mental age matches your chronological age, your IQ is 100 (average). If your mental age is 12 while your chronological age is 10, you would have an above-average IQ of 120.

WISC and WAIS

• Dissatisfied with the limitations of the Stanford-Binet test, American psychologist David Wechsler developed the Wechsler Intelligence Scale for Children (WISC) and the Wechsler Adult Intelligence Scale (WAIS) in 1955 (Cherry, 2020).
• Wechsler believed in the multifaceted nature of intelligence, contrasting the idea of a single general intelligence.
• The WISC is designed for children aged 6 to 16 and has been updated to its fourth edition (WISC-V) in 2014 by Pearson.
• The WAIS is intended for adults and older adolescents, measuring cognitive abilities including verbal comprehension, perceptual reasoning, working memory, and processing speed.
• The latest version of the WAIS, the WAIS-IV, was standardized on a diverse group of 2,200 individuals aged 16 to 90 (Brooks et al., 2011).
• Standardization involves administering the test to various age groups to calculate average scores for each age level.
• The overall IQ score is based on the test taker's performance across all four categories (Cherry, 2020).
• Unlike the Binet-Simon approach of comparing mental and chronological age, the WAIS compares an individual's score to the average score for their age level, as determined through the standardization process.

The Flynn Effect

• Regular standardization of intelligence tests is essential due to potential changes in the overall level of intelligence in a population over time.
• The Flynn effect, named after New Zealand researcher James Flynn, describes the phenomenon of increasing scores on intelligence tests globally over successive decades (Flynn, 1984).

Aptitude vs. Achievement Tests

• Aptitude and achievement tests are designed to assess intellectual capabilities.
• Achievement tests gauge what a student has already learned, such as subject-specific exams like history or math.
• Aptitude tests, on the other hand, evaluate a student's potential or capacity to learn (Anastasi, 1984).
• Unlike IQ tests, aptitude tests often focus on measuring specific abilities within particular domains.

Criticism Of Intelligence Testing

• Criticisms of IQ tests include claims of bias in favor of white, middle-class individuals.
• Negative stereotypes related to ethnicity, gender, or age can lead to stereotype threat, where individuals experience self-doubt about their abilities due to these stereotypes.
• Stereotype threat can generate anxiety and subsequently lead to lower scores on IQ tests.

Reliability and Construct Validity

• Intelligence tests are reliable and possess high construct validity, assuring their credibility.
• Reliability implies consistency over time, and IQ scores tend to remain relatively stable when taking the same test on multiple occasions (Tuma & Appelbaum, 1980).
• Although some fluctuations may occur, intelligence tests generally exhibit high reliability.
• These tests also demonstrate strong construct validity, indicating that they genuinely measure intelligence rather than something else.
• Researchers invest significant effort in developing, standardizing, and adapting these tests to ensure their accuracy and relevance.
• Nevertheless, intelligence tests are not without flaws; errors can arise in scoring and interpreting the multiple scores they provide.
• Some studies question the overall validity, reliability, and clinical utility of these tests for individual use (Canivez, 2013).
• Intelligence scores may be influenced by the underlying theory upon which a test is based, affecting their interpretation (Canivez, 2013).

Cultural Specificity

• Intelligence tests were primarily developed by Western psychologists and reflect Euro-centric values.
• The cultural specificity of these tests is crucial, as the majority of the world's population resides outside Europe and North America.
• Different cultures have distinct values and perceptions of intelligence, challenging the idea of a universal marker for this complex concept.
• For example, Kenyan parents defined intelligence as the ability to act without being told what to do around the homestead (Harkness et al., 1992), whereas some Ugandans consider intelligent individuals to be slow in thought and action (Wober, 1974).
• These examples highlight the flexibility in defining intelligence, making it challenging to capture in a single test or number.
• Even within the United States, perceptions of intelligence can differ. For instance, in San Jose, California, Latino, Asian, and Anglo parents had varying definitions of intelligence.
• Teachers' understanding of intelligence was more aligned with the Asian and Anglo communities, and this similarity correlated with students' academic performance (Okagaki & Sternberg, 1993).
• Intelligence varies across countries and cultures, and while IQ tests may measure academic intelligence reliably and validly, understanding the role of culture is crucial for a comprehensive understanding of an individual's intelligence.
• More research is needed to determine whether IQ tests accurately measure practical intelligence and general intelligence across all cultures.

Social and Environmental Factors

• The social and environmental context in which an individual lives plays a significant role in understanding IQ test-related biases.
• Social factors can contribute to variations in IQ scores, as the threat of social exclusion can hinder the expression of intelligence.
• In a 2002 study, participants received an IQ test and a personality inventory. Some were randomly informed that they were likely to end up alone in life (Baumeister et al., 2002).
• After this feedback, those who were told about potential social isolation answered significantly fewer questions in a second test compared to the earlier one.
• These findings reflect the impact of social exclusion threats on the expression of intelligence, and this effect can extend to real-world situations where not only social exclusion but also perceived threats to physical safety can affect academic performance.
• Poor academic performance in children can be linked to disadvantaged and potentially unsafe communities in which they grow up.

Stereotype Threat

• Stereotype threat is a phenomenon where individuals feel pressured to conform to negative stereotypes about their social group, leading to anxiety and lower performance.
• In a study involving Black and White college students, a verbal section of the GRE was administered.
• In the stereotype threat condition, students were told that the test diagnosed intellectual ability, potentially making the stereotype that Blacks are less intelligent than Whites more salient (Steele & Aronson, 1995).
• Results showed that in the stereotype threat condition, Black students performed worse than White students, while in the no stereotype threat condition, both Black and White students performed equally well.
• Even the simple act of recording one's race can lead to worsened performance, highlighting the real and detrimental impact of stereotype threat on individuals' test performance.

Self-Fulfilling Prophecy

• Stereotype threat is linked to the concept of a self-fulfilling prophecy, where an individual's expectations about someone can lead that person to conform to those expectations.
• An experiment in a California elementary school involved students taking an IQ test, and teachers were informed of the students who were expected to be "intellectual bloomers" based on the test results (Rosenthal & Jacobson, 1968).
• After retesting the students with the same IQ test at the end of the study, those labeled as "intellectual bloomers" significantly increased their scores.
• This experiment illustrates how teachers' subconscious behaviors can influence the success of certain students and impact their achievement (Rosenthal & Jacobson, 1968).
• It emphasizes the importance of considering less visible factors that contribute to an individual's intelligence.
• While IQ scores have benefits in measuring intelligence, it is crucial to understand that a lower score does not necessarily imply lower intelligence.
• Several factors can affect test performance, and these tests may not accurately measure the intended concept of intelligence.

Extremes of Intelligence

• IQ scores generally follow a normal distribution, with approximately 95% of the population falling between IQ scores of 70 and 130 (Moore et al., 2013).
• Individuals outside this range represent the extremes of intelligence.
• Those with IQ scores above 130 are considered gifted (Lally & French, 2018), such as Christopher Langan, who has an IQ score around 200 (Gladwell, 2008).
• Individuals with scores below 70 typically have intellectual disabilities characterized by significant developmental delays, including motor, cognitive, and speech delays (De Light, 2012).
• Some intellectual disabilities result from genetic mutations, like Down syndrome, caused by extra genetic material from the 21st chromosome (Breslin, 2014), leading to below-average IQ scores in many cases (Breslin, 2014).
• Savant syndrome is another example of extreme intelligence, where individuals with significant mental disabilities excel in specific fields like memorization, mathematical calculation, or musical talent (Treffert, 2009).
• Despite lacking in certain areas like social interaction and communication, individuals with savant syndrome demonstrate remarkable abilities, highlighting the complexity of intelligence and its various dimensions.
• Recognizing and measuring intelligence in society requires consideration of all individuals and their unique abilities.

Intelligence Today

• Today, intelligence is generally defined as the capacity to understand and adapt to the environment through a combination of inherited abilities and acquired knowledge.
• Numerous new intelligence tests have emerged, including online assessments like the University of California Matrix Reasoning Task (Pahor et al., 2019).
• These tests are efficient and can be completed quickly, with new scoring methods developed to enhance accuracy (Sansone et al., 2014).
• Admission to universities and graduate schools often relies on aptitude and achievement tests such as the SAT, ACT, and LSAT, which have become integral to our lives.
• Human intelligence is a remarkable attribute, and our species' overall intelligence has been vital to our enduring success across generations.