How is fluid intelligence generally affected over time?

Fluid intelligence refers to the capacity to think logically and solve problems in novel situations, independent of acquired knowledge. This type of intelligence is generally associated with reasoning, pattern recognition, and abstract thinking. Research has shown that fluid intelligence tends to peak in early adulthood and subsequently decreases with age. This decline can be gradual, reflecting how cognitive processing speed, mental flexibility, and working memory may deteriorate as individuals grow older.

The decrease in fluid intelligence contrasts with crystallized intelligence, which is based on accumulated knowledge and experience and often remains stable or even improves with age. Thus, the idea that fluid intelligence decreases linearly with age accurately captures its typical trajectory throughout the lifespan. Understanding this difference between fluid and crystallized intelligence is essential in developmental psychology as it emphasizes how cognitive capabilities can evolve over time due to aging.