Cognitive variables are means people use every day to process information. These variables are used to describe why one person is lacking in artistic ability, yet exhibits high competence in a specific area, such as electronics. Each person seems to have these variables in differing degrees, and scientists seek correlations between the variables, perhaps hoping to see if one might cause or add to another.

Semantic and Episodic Memory

"Memory" is the storage of information and past experiences for the purpose of present-day application or use. In semantic memory, an individual relies on schemes to order his memories so as to make sense of himself and others. This occurs through language, which gives memories meaning or semantic importance. "Episodic memory" refers to events in a person's life that are retold as narratives. Episodic memories coalesce to form semantic memories. For instance, one's college career may be related in a series of episodes that are synthesized into a semantic whole, or meaning.

Intelligence

Intelligence is often measured in terms of the Intelligence Quotient, or IQ. IQ is a measure of your ability to solve problems and understand concepts. There is a strong correlation between having a high IQ and academic success. Intelligence is considered separately from knowledge, as the acquisition of facts does not necessarily indicate an ability to apply the concepts or use them in a problem-solving context. There is debate as to whether genetics or environment affect IQ more, but it does appear to remain steady as a person ages.

Aptitude

"Aptitude" generally refers to an individual's verbal, numerical or abstract reasoning skills. For the sake of practical application, aptitude refers to a person's ability to learn or adapt certain new skills. For instance, a potential surgeon may be tested for cognitive knowledge and psychomotor ability, two areas deemed pertinent to the career of a surgeon. Others may exhibit strengths in different aptitudes, as aptitudes are seen as distinct and independent of one another.

Cognitive Style

People have different ways in which they acquire and process information, methods collectively called cognitive style. Cognitive style is considered a stable part of a person's personality, as it forms the basis of how he interacts with his world, both in thought and action. For instance, some may have a holistic style, which sees tasks in a broad perspective to gain an overview and context. Others may exhibit a serialistic style, which sees tasks and arguments in terms of their steps. With a narrow focus, serialists break down each step of an argument or task, seeking to avoid wasteful redundancies.