It is commonly believed that intelligence declines as we age, but this is an erroneous belief. Countless people will argue that there are various cognitive processes associated with changes in the brain that deteriorate over time, but that there are also other areas of the brain that increase their activity in old age. I believe that a person's ability to perform certain tasks may become slower as they age, but that does not automatically mean that they become cognitively less intelligent. There are many ways to define intelligence, although it is commonly defined as general cognitive skills, this means that it is a mental ability involved in the ability to learn, reason, perceive relationships and analogies, understanding, facts, meanings, etc. . (Dictionary definition). However, Raymond Cattell (1963) argued that "intelligence does not generally consist of cognitive performance alone." Cattell and Horns' theory developed in 1966 and emphasizes that intelligence is made up of a number of different abilities that interact to form the general term intelligence. The two main factors are crystallized and fluid intelligence. Several people have developed the idea that as a person ages their intelligence will decrease, this hypothesis was developed through the idea that as an individual's age increases their intelligence abilities fluid deteriorate. However, there is more to intelligence than just fluid intelligence. Crystallized intelligence works in much the same way, except in reverse, with older generations having more crystallized intelligence than younger adolescents. Crystallized intelligence consists of learned skills and knowledge that come from...... middle of article...... March 17, 2014. http://psych.answers.com/research-methods /defining-and- providing examples of fluid intelligence Horn, JL and Cattell, RB (1967). "Age differences in fluid and crystallized intelligence". Acta Psychological, 26, 107-129. Knapton, S 2014, “Older people's brains slow down because they know so much” Telegraph Media Group, published in the Journal of Topics in Cognitive Science, accessed March 22, 2014 http://www.telegraph.co. uk/science/science-news/10584927/Brains-of-elderly-slow-because-they-know-so-much.html Williams, Y 2003, “Retrieval cues: definition, examples and quizzes” Education portal, viewed on 22 March 2014 http://education-portal.com/academy/lesson/retrieval-cues-definition-examples-quiz.html#lesson 2013, 'Dementia' Australian Institute of Health and Welfare, accessed 26 March http://www .aihw.gov.au/dementia/