Flynn Effect

The Flynn Effect, a phenomenon in intelligence research, reflects the consistent rise in average IQ scores across generations. It is shaped by factors like IQ measures, generational trends, and environmental influences. This effect has applications in education policy and psychological research, offering benefits such as improved education and insights into human intelligence. Challenges include addressing environmental disparities and understanding cultural-genetic interactions. Real-world examples demonstrate educational gains and global variations in IQ score increases.

Introduction to the Flynn Effect

The Flynn Effect is named after James R. Flynn, a political philosopher and intelligence researcher who extensively documented the trend of rising IQ scores over time. The phenomenon was first identified by Flynn in the 1980s when he observed that IQ test scores were increasing across different countries at a rate of approximately 3 points per decade. This finding challenged the long-standing assumption that intelligence, as measured by IQ tests, was relatively stable and genetically determined.

The Flynn Effect has since become a well-documented and widely studied phenomenon, raising important questions about the nature of intelligence, the factors contributing to cognitive gains, and the implications for education and society.

Key Characteristics of the Flynn Effect

To better understand the Flynn Effect, let’s examine its key characteristics:

  1. Consistency: The Flynn Effect is characterized by its consistency across diverse populations and age groups. It has been observed in both developed and developing countries, across different ethnicities, and in individuals of various ages.
  2. Magnitude: The rate of increase in IQ scores associated with the Flynn Effect is substantial, with an average gain of about 3 IQ points per decade. Over the course of a century, this translates into a significant increase in average IQ scores.
  3. Broad Cognitive Gains: The Flynn Effect is not limited to specific cognitive domains but encompasses gains in various areas, including verbal and mathematical abilities, spatial reasoning, and general knowledge.
  4. Age Cohort Differences: One intriguing aspect of the Flynn Effect is that it primarily reflects changes in the scores of younger generations compared to older ones. This suggests that the increase in IQ scores is not due to biological factors but rather environmental or cultural influences.
  5. Normalization of Test Scores: To account for the rising scores and maintain a constant mean IQ of 100, IQ tests are periodically renormed. This means that a person scoring 100 on an IQ test today would likely score higher than 100 on an earlier version of the same test.

Proposed Explanations for the Flynn Effect

The Flynn Effect has sparked numerous hypotheses and explanations, and researchers continue to debate its underlying causes. Some of the leading theories and explanations include:

  1. Environmental Factors: Many researchers believe that environmental factors, such as improvements in nutrition, healthcare, and education, have played a significant role in the Flynn Effect. Better access to education and cognitive stimulation, along with reduced exposure to environmental toxins, may contribute to cognitive gains.
  2. Technological Advances: The rapid advancements in technology and access to information may enhance cognitive abilities. Exposure to digital technology, including computers and the internet, may provide individuals with new opportunities for learning and problem-solving.
  3. Changes in Education: Educational practices have evolved over the decades, with a greater emphasis on cognitive skills, critical thinking, and problem-solving. Improved teaching methods and curricular changes may contribute to cognitive gains.
  4. Socioeconomic Factors: Reductions in poverty and improvements in living conditions may have a positive impact on cognitive development. Socioeconomic factors, such as access to quality healthcare and early childhood education, are linked to cognitive gains.
  5. Test-Taking Skills: Some researchers suggest that individuals today may have better test-taking skills or strategies, which could contribute to higher IQ scores on standardized tests.
  6. Familial Factors: Changes in family structure, parenting practices, and family dynamics may influence cognitive development. Factors such as smaller family sizes and increased parental involvement may contribute to cognitive gains.
  7. Differential Fertility: Some researchers propose that individuals with higher cognitive abilities may be having more children, leading to a genetic component of the Flynn Effect.
  8. Cultural Changes: Shifts in cultural norms, values, and expectations may influence cognitive development. Changes in what is considered important or valued in society may affect the development of cognitive skills.

Implications of the Flynn Effect

The Flynn Effect has far-reaching implications for psychology, education, and society:

  1. Redefining Intelligence: The Flynn Effect challenges the notion that intelligence is a fixed and unchanging trait. It suggests that intelligence is malleable and influenced by environmental factors, offering hope for interventions to improve cognitive abilities.
  2. Educational Policy: The recognition that environmental factors contribute to cognitive gains has implications for educational policy. Efforts to improve access to quality education, early childhood interventions, and nutritional support may have a positive impact on cognitive development.
  3. Assessment and Norming: The Flynn Effect necessitates periodic renorming of IQ tests to account for rising scores. This ensures that IQ scores remain a meaningful measure of cognitive abilities.
  4. Cultural Awareness: The Flynn Effect underscores the importance of cultural and environmental factors in shaping cognitive abilities. It highlights the need for cultural sensitivity in educational and psychological assessments.
  5. Societal Changes: The Flynn Effect may be linked to broader societal changes, including shifts in the nature of work, technology, and communication. Understanding these changes can inform strategies for preparing individuals for the challenges of the modern world.

Ongoing Debate and Future Research

While the Flynn Effect has been extensively studied, the debate surrounding its causes and implications continues. Some areas of ongoing research and debate include:

  1. Diminishing Returns: Some researchers have suggested that the Flynn Effect may be slowing down or reaching a plateau in some regions. Understanding whether there are limits to cognitive gains is a topic of interest.
  2. Cross-Cultural Variability: The Flynn Effect is not uniform across all countries and populations. Investigating the factors that contribute to cross-cultural differences in cognitive gains is an area of research.
  3. Long-Term Trends: Examining the long-term trends of the Flynn Effect and its potential reversal or stabilization is an important avenue for future research.
  4. Genetic Contributions: The extent to which genetic factors contribute to the Flynn Effect, such as through differential fertility, remains a topic of exploration.
  5. Impact of Technology: Investigating the role of technology and digital media in cognitive development and the potential trade-offs associated with increased screen time.


The Flynn Effect challenges conventional wisdom about the stability of intelligence and underscores the profound influence of environmental factors on cognitive development. While it has provided valuable insights into the changing nature of intelligence, it also leaves many questions unanswered. As researchers continue to investigate the causes and consequences of the Flynn Effect, it is clear that our understanding of human cognition and its relationship to the changing world is a dynamic and evolving field of study.

Case Studies

  • IQ Test Scores: One of the most prominent examples is the increase in average IQ test scores over the past century, which is a hallmark of the Flynn Effect.
  • Educational Achievement: Educational gains observed in standardized tests and assessments, where students today tend to perform better academically compared to previous generations.
  • Cross-Cultural Variations: Variations in the Flynn Effect across different countries and cultures. For instance, some countries may experience more significant increases in IQ scores than others.
  • Nutrition Impact: Improved nutrition as a contributing factor, with access to better food and nutrition playing a role in cognitive development.
  • Access to Education: Differences in access to quality education and its influence on the Flynn Effect. Regions with improved educational opportunities tend to show greater gains in IQ scores.
  • Parenting Practices: Changes in parenting practices and the emphasis on intellectual stimulation in early childhood education, potentially contributing to rising IQ scores.
  • Technology Advancements: The role of technological advancements and increased exposure to information and learning resources in shaping cognitive abilities.
  • Socioeconomic Status: The correlation between socioeconomic status and IQ score increases, where individuals from higher socioeconomic backgrounds may experience more substantial gains.
  • Cultural Shifts: Cultural shifts in attitudes toward education and the value placed on intellectual pursuits as factors that influence IQ trends.
  • Gender Differences: Examining whether gender differences play a role in the Flynn Effect, with studies investigating whether men and women show different patterns of IQ score increases.
  • Generational Changes: Observing how the Flynn Effect manifests in different generations within families, such as grandparents, parents, and grandchildren.
  • Longitudinal Studies: Longitudinal studies tracking individual IQ scores over time, providing insights into how cognitive abilities evolve within individuals.
  • Public Policy Impact: The impact of the Flynn Effect on public policy decisions related to education, workforce development, and social programs.
  • Global Awareness: Increased global awareness of the Flynn Effect and its implications for addressing educational disparities and fostering cognitive development worldwide.
  • Scientific Research: Ongoing scientific research aimed at understanding the underlying causes of the Flynn Effect, including genetic, environmental, and cultural factors.

Key highlights

  • IQ Score Increase: The Flynn Effect refers to the consistent and substantial increase in average IQ scores over successive generations.
  • Environmental Influence: Environmental factors, such as improved nutrition, access to education, and changes in parenting practices, play a significant role in driving the effect.
  • Generational Trend: The effect is characterized by a generational trend where each new generation tends to score higher on IQ tests than the previous one.
  • Educational Implications: The Flynn Effect has important implications for education policy, curriculum development, and teaching strategies to accommodate rising IQ scores.
  • Psychological Research: It serves as a valuable framework for psychological research on intelligence and cognitive development, shedding light on the malleability of human intelligence.
  • Improved Education: Understanding the Flynn Effect has led to improved education methods and better learning outcomes, benefiting students and educators.
  • Insights into Human Intelligence: The phenomenon offers insights into the complex interplay of genetic, environmental, and cultural factors that shape human intelligence.
  • Global Variations: While a global phenomenon, the rate of IQ score increases varies across countries and regions, highlighting the influence of local factors.
  • Challenges: Addressing disparities in environmental factors and exploring cultural and genetic interactions are ongoing challenges in understanding the Flynn Effect.
  • Longitudinal Studies: Longitudinal studies and ongoing scientific research continue to provide insights into the causes and consequences of this intriguing phenomenon.

Connected Thinking Frameworks

Convergent vs. Divergent Thinking

Convergent thinking occurs when the solution to a problem can be found by applying established rules and logical reasoning. Whereas divergent thinking is an unstructured problem-solving method where participants are encouraged to develop many innovative ideas or solutions to a given problem. Where convergent thinking might work for larger, mature organizations where divergent thinking is more suited for startups and innovative companies.

Critical Thinking

Critical thinking involves analyzing observations, facts, evidence, and arguments to form a judgment about what someone reads, hears, says, or writes.


The concept of cognitive biases was introduced and popularized by the work of Amos Tversky and Daniel Kahneman in 1972. Biases are seen as systematic errors and flaws that make humans deviate from the standards of rationality, thus making us inept at making good decisions under uncertainty.

Second-Order Thinking

Second-order thinking is a means of assessing the implications of our decisions by considering future consequences. Second-order thinking is a mental model that considers all future possibilities. It encourages individuals to think outside of the box so that they can prepare for every and eventuality. It also discourages the tendency for individuals to default to the most obvious choice.

Lateral Thinking

Lateral thinking is a business strategy that involves approaching a problem from a different direction. The strategy attempts to remove traditionally formulaic and routine approaches to problem-solving by advocating creative thinking, therefore finding unconventional ways to solve a known problem. This sort of non-linear approach to problem-solving, can at times, create a big impact.

Bounded Rationality

Bounded rationality is a concept attributed to Herbert Simon, an economist and political scientist interested in decision-making and how we make decisions in the real world. In fact, he believed that rather than optimizing (which was the mainstream view in the past decades) humans follow what he called satisficing.

Dunning-Kruger Effect

The Dunning-Kruger effect describes a cognitive bias where people with low ability in a task overestimate their ability to perform that task well. Consumers or businesses that do not possess the requisite knowledge make bad decisions. What’s more, knowledge gaps prevent the person or business from seeing their mistakes.

Occam’s Razor

Occam’s Razor states that one should not increase (beyond reason) the number of entities required to explain anything. All things being equal, the simplest solution is often the best one. The principle is attributed to 14th-century English theologian William of Ockham.

Lindy Effect

The Lindy Effect is a theory about the ageing of non-perishable things, like technology or ideas. Popularized by author Nicholas Nassim Taleb, the Lindy Effect states that non-perishable things like technology age – linearly – in reverse. Therefore, the older an idea or a technology, the same will be its life expectancy.


Antifragility was first coined as a term by author, and options trader Nassim Nicholas Taleb. Antifragility is a characteristic of systems that thrive as a result of stressors, volatility, and randomness. Therefore, Antifragile is the opposite of fragile. Where a fragile thing breaks up to volatility; a robust thing resists volatility. An antifragile thing gets stronger from volatility (provided the level of stressors and randomness doesn’t pass a certain threshold).

Systems Thinking

Systems thinking is a holistic means of investigating the factors and interactions that could contribute to a potential outcome. It is about thinking non-linearly, and understanding the second-order consequences of actions and input into the system.

Vertical Thinking

Vertical thinking, on the other hand, is a problem-solving approach that favors a selective, analytical, structured, and sequential mindset. The focus of vertical thinking is to arrive at a reasoned, defined solution.

Maslow’s Hammer

Maslow’s Hammer, otherwise known as the law of the instrument or the Einstellung effect, is a cognitive bias causing an over-reliance on a familiar tool. This can be expressed as the tendency to overuse a known tool (perhaps a hammer) to solve issues that might require a different tool. This problem is persistent in the business world where perhaps known tools or frameworks might be used in the wrong context (like business plans used as planning tools instead of only investors’ pitches).

Peter Principle

The Peter Principle was first described by Canadian sociologist Lawrence J. Peter in his 1969 book The Peter Principle. The Peter Principle states that people are continually promoted within an organization until they reach their level of incompetence.

Straw Man Fallacy

The straw man fallacy describes an argument that misrepresents an opponent’s stance to make rebuttal more convenient. The straw man fallacy is a type of informal logical fallacy, defined as a flaw in the structure of an argument that renders it invalid.

Streisand Effect

The Streisand Effect is a paradoxical phenomenon where the act of suppressing information to reduce visibility causes it to become more visible. In 2003, Streisand attempted to suppress aerial photographs of her Californian home by suing photographer Kenneth Adelman for an invasion of privacy. Adelman, who Streisand assumed was paparazzi, was instead taking photographs to document and study coastal erosion. In her quest for more privacy, Streisand’s efforts had the opposite effect.


As highlighted by German psychologist Gerd Gigerenzer in the paper “Heuristic Decision Making,” the term heuristic is of Greek origin, meaning “serving to find out or discover.” More precisely, a heuristic is a fast and accurate way to make decisions in the real world, which is driven by uncertainty.

Recognition Heuristic

The recognition heuristic is a psychological model of judgment and decision making. It is part of a suite of simple and economical heuristics proposed by psychologists Daniel Goldstein and Gerd Gigerenzer. The recognition heuristic argues that inferences are made about an object based on whether it is recognized or not.

Representativeness Heuristic

The representativeness heuristic was first described by psychologists Daniel Kahneman and Amos Tversky. The representativeness heuristic judges the probability of an event according to the degree to which that event resembles a broader class. When queried, most will choose the first option because the description of John matches the stereotype we may hold for an archaeologist.

Take-The-Best Heuristic

The take-the-best heuristic is a decision-making shortcut that helps an individual choose between several alternatives. The take-the-best (TTB) heuristic decides between two or more alternatives based on a single good attribute, otherwise known as a cue. In the process, less desirable attributes are ignored.

Bundling Bias

The bundling bias is a cognitive bias in e-commerce where a consumer tends not to use all of the products bought as a group, or bundle. Bundling occurs when individual products or services are sold together as a bundle. Common examples are tickets and experiences. The bundling bias dictates that consumers are less likely to use each item in the bundle. This means that the value of the bundle and indeed the value of each item in the bundle is decreased.

Barnum Effect

The Barnum Effect is a cognitive bias where individuals believe that generic information – which applies to most people – is specifically tailored for themselves.

First-Principles Thinking

First-principles thinking – sometimes called reasoning from first principles – is used to reverse-engineer complex problems and encourage creativity. It involves breaking down problems into basic elements and reassembling them from the ground up. Elon Musk is among the strongest proponents of this way of thinking.

Ladder Of Inference

The ladder of inference is a conscious or subconscious thinking process where an individual moves from a fact to a decision or action. The ladder of inference was created by academic Chris Argyris to illustrate how people form and then use mental models to make decisions.

Goodhart’s Law

Goodhart’s Law is named after British monetary policy theorist and economist Charles Goodhart. Speaking at a conference in Sydney in 1975, Goodhart said that “any observed statistical regularity will tend to collapse once pressure is placed upon it for control purposes.” Goodhart’s Law states that when a measure becomes a target, it ceases to be a good measure.

Six Thinking Hats Model

The Six Thinking Hats model was created by psychologist Edward de Bono in 1986, who noted that personality type was a key driver of how people approached problem-solving. For example, optimists view situations differently from pessimists. Analytical individuals may generate ideas that a more emotional person would not, and vice versa.

Mandela Effect

The Mandela effect is a phenomenon where a large group of people remembers an event differently from how it occurred. The Mandela effect was first described in relation to Fiona Broome, who believed that former South African President Nelson Mandela died in prison during the 1980s. While Mandela was released from prison in 1990 and died 23 years later, Broome remembered news coverage of his death in prison and even a speech from his widow. Of course, neither event occurred in reality. But Broome was later to discover that she was not the only one with the same recollection of events.

Crowding-Out Effect

The crowding-out effect occurs when public sector spending reduces spending in the private sector.

Bandwagon Effect

The bandwagon effect tells us that the more a belief or idea has been adopted by more people within a group, the more the individual adoption of that idea might increase within the same group. This is the psychological effect that leads to herd mentality. What in marketing can be associated with social proof.

Moore’s Law

Moore’s law states that the number of transistors on a microchip doubles approximately every two years. This observation was made by Intel co-founder Gordon Moore in 1965 and it become a guiding principle for the semiconductor industry and has had far-reaching implications for technology as a whole.

Disruptive Innovation

Disruptive innovation as a term was first described by Clayton M. Christensen, an American academic and business consultant whom The Economist called “the most influential management thinker of his time.” Disruptive innovation describes the process by which a product or service takes hold at the bottom of a market and eventually displaces established competitors, products, firms, or alliances.

Value Migration

Value migration was first described by author Adrian Slywotzky in his 1996 book Value Migration – How to Think Several Moves Ahead of the Competition. Value migration is the transferal of value-creating forces from outdated business models to something better able to satisfy consumer demands.

Bye-Now Effect

The bye-now effect describes the tendency for consumers to think of the word “buy” when they read the word “bye”. In a study that tracked diners at a name-your-own-price restaurant, each diner was asked to read one of two phrases before ordering their meal. The first phrase, “so long”, resulted in diners paying an average of $32 per meal. But when diners recited the phrase “bye bye” before ordering, the average price per meal rose to $45.


Groupthink occurs when well-intentioned individuals make non-optimal or irrational decisions based on a belief that dissent is impossible or on a motivation to conform. Groupthink occurs when members of a group reach a consensus without critical reasoning or evaluation of the alternatives and their consequences.


A stereotype is a fixed and over-generalized belief about a particular group or class of people. These beliefs are based on the false assumption that certain characteristics are common to every individual residing in that group. Many stereotypes have a long and sometimes controversial history and are a direct consequence of various political, social, or economic events. Stereotyping is the process of making assumptions about a person or group of people based on various attributes, including gender, race, religion, or physical traits.

Murphy’s Law

Murphy’s Law states that if anything can go wrong, it will go wrong. Murphy’s Law was named after aerospace engineer Edward A. Murphy. During his time working at Edwards Air Force Base in 1949, Murphy cursed a technician who had improperly wired an electrical component and said, “If there is any way to do it wrong, he’ll find it.”

Law of Unintended Consequences

The law of unintended consequences was first mentioned by British philosopher John Locke when writing to parliament about the unintended effects of interest rate rises. However, it was popularized in 1936 by American sociologist Robert K. Merton who looked at unexpected, unanticipated, and unintended consequences and their impact on society.

Fundamental Attribution Error

Fundamental attribution error is a bias people display when judging the behavior of others. The tendency is to over-emphasize personal characteristics and under-emphasize environmental and situational factors.

Outcome Bias

Outcome bias describes a tendency to evaluate a decision based on its outcome and not on the process by which the decision was reached. In other words, the quality of a decision is only determined once the outcome is known. Outcome bias occurs when a decision is based on the outcome of previous events without regard for how those events developed.

Hindsight Bias

Hindsight bias is the tendency for people to perceive past events as more predictable than they actually were. The result of a presidential election, for example, seems more obvious when the winner is announced. The same can also be said for the avid sports fan who predicted the correct outcome of a match regardless of whether their team won or lost. Hindsight bias, therefore, is the tendency for an individual to convince themselves that they accurately predicted an event before it happened.

Read Next: BiasesBounded RationalityMandela EffectDunning-Kruger EffectLindy EffectCrowding Out EffectBandwagon Effect.

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