Final answer:
Crystallized and fluid intelligence help explain age-related changes in IQ scores. Crystallized intelligence refers to acquired knowledge, while fluid intelligence involves problem-solving abilities. Crystallized intelligence tends to hold steady or improve with age, while fluid intelligence declines in late adulthood.
Step-by-step explanation:
Age-related changes in IQ scores can be explained by the concepts of crystallized and fluid intelligence. Crystallized intelligence refers to acquired knowledge and the ability to retrieve it, while fluid intelligence involves the ability to see complex relationships and solve problems. As we age, crystallized intelligence tends to hold steady or even improve, as it is based on the information and skills we have gathered throughout our lives. However, fluid intelligence tends to decline in late adulthood, leading to decreases in IQ scores. Factors such as mental and physical activity can help delay the onset of cognitive decline.