Cognitive psychology studies human perceptions and how cognitive processes operate. Cognitive processes are numerous and include perceiving, recognizing, remembering, conceptualizing, imagining, reasoning, judging, and processing information. One of the important fields of cognitive psychology is the mutual influences of genetics and environment in influencing cognitive capabilities and their development. Other fields of interest include cognitive reaction to stimuli, language acquisition; sensory perception; storage and retrieval of information; cognitive restructuring, and altered states of consciousness.

Jerome Bruner and Leo Postman, who were pioneers of cognitive sociology, studied how motivations, needs, and expectations affect perception. Bruner also worked education and cognitive development of children and developed a theory of cognitive growth. His theory focuses on how the environment and experience influence patterns of development. Another influential cognitive psychologist, Leon Festinger, formulated his theory of cognitive dissonance in 1957. This theory studies how people deal with conflicting notions and ideas and postulates that conflicting ideas (dissonance) result in modifying some of the conflicting ideas to bring them into alinement with other ideas. Psycholinguistics of Noam Chomsky states that in every human there is an underlying and deep logical structure, that is genetically determined, and not learned, and that encompasses all languages, and allows anyone to easily learn any language as its first language. Jerome Bruner and George A. Miller established the Harvard Center for Cognitive Studies, in 1960. The advances in related fields of neuroscience, mathematics, anthropology, and computer science helped cognitive psychology implement new methods and ideas. Other well-known cognitive psychologists are: Daniel E. Berlyne, George Kelly, Herman Witkin, Riley Gardner, George Klein, George Miller, Eugen Galanter, Karl Pribram, and Donald E. Broadbent.

Books: 

Bruner, Jerome. A Study of Thinking (1956);

The Process of Education (1960);

Studies in Cognitive Growth (1966);

Toward a Theory of Instruction (1966);

Processes of Cognitive Growth: Infancy (1968);

Beyond the Information Given: Studies in the Psychology of Knowing (1973);

Chomsky, Noam. Syntactic Structures (1957);

Festinger, Leon. A Theory of Cognitive Dissonance (1957).