Identify one known major application of crystallization.

There are a number of methods to test intelligence and these methods have often been used to support the eugenics movement. Explore the history of intelligence testing and the evolution of the eugenics movement.

Charles Spearman was an experimental psychologist who was interested in intelligence. Read about Spearman's background, his g factor theory and how Spearman's work continues to influence the field of psychology today.

Alfred Binet designed the first intelligence test to identify students who needed extra support. Explore Binet's theories on intelligence, then discover his impact on intelligence testing in education.

Sexuality is an important part of most adults' lives, but as people age, they can experience changes in their sexuality. Learn about sexual functioning and the changes regarding sex that often occur in middle adulthood, including sexual dysfunction and changes in the frequency of sex.

Lewis Terman was an American psychologist whose early 20th century work has been profoundly influential in the field of educational psychology. Through this lesson, you'll explore his biography and learn about his contributions to the testing of intelligence quotients.

Research approaches to intelligence mainly involve various methods of measurement. Learn about measuring constructs, psychometrics, information processing, and cognitive structural approaches.

Postformal thought in cognitive development involves understanding the existence of contradictions in the world. Explore the concept of postformal thought, learn how to explain relativistic thinking and dialectical reasoning, and identify how the cognitive skills that develop during early adulthood differ.

The study of intelligence centers around two key influences: environment and genetics. Read evidence relating to both of these major factors, learn information from studies of identical and fraternal twins, and consider the steady rise of IQ scores.

Adult intelligence and creativity do not change as a person ages, but the components of intelligence can. Learn how age impacts intelligence, explore challenges to traditional thought, and then learn about the changing components of intelligence, including fluid and crystallized intelligence.

The Flynn effect refers to James Flynn's discovery that average intelligence scores have increased steadily over the past century in Western industrialized nations. Explore the definition/explanation of the Flynn effect, the types of intelligence, and nature vs. nurture.

Panic disorders are characterized by the frequency of panic attacks paired with the fear of more attacks occurring, which leads to a change in behavior to avoid such anxieties. Learn more about panic disorders, panic attacks and their causes, and specific phobias such as agoraphobia.

David Wechsler introduced the theory that intelligence is a multidimensional global capacity that should be measured as an age-appropriate performance skill. Explore an overview of Wechsler's definition of intelligence and discover the tests he created for measuring it.

Wisdom is defined as knowledge that is gained from personal experience. Learn more about the philosophical application of wisdom vs. the practical, the difference between formal and post-formal operations, and how wisdom relates to morality.

Psychologist George Miller theorized it is possible to commit no more than seven new items to one's short-term memory, plus or minus two. Explore short-term memory and discover more about Miller's landmark research.

This lesson provides biographical information on the psychologist Raymond Cattell and also explains his theory on personality, which was a major contribution to the field of psychology.

During middle age, adults may notice that some of their cognitive processes are not as sharp as before. Explore mental skills that decline in middle adulthood, including information processing and working memory.