Piaget’s Theory of Cognitive Development Developmental psychologist,
Jean Piaget, theorized that one's cognitive ability, or intelligence – defined as the ability to adapt to all aspects of reality – evolves through a series of four qualitatively distinct stages (the
sensorimotor,
pre-operational,
concrete operational and
formal operational stages). Piaget's theory describes three core cognitive processes that serve as mechanisms for transitioning from one stage to the next. Piaget's core processes for developmental change: •
Assimilation: The process of transforming new information so that it fits with ones' existing way of thinking. Piaget's theory holds that transitioning from one stage of development to the next is not only a result of assimilation, accommodation, and equilibration, but also a result of developmental changes in domain-general mechanisms. As humans mature, various domain-general mechanisms become more sophisticated, and thus, according to Piaget, allow for growth in cognitive functioning. For example, Piaget's theory notes that the humans transition into the concrete operation stage of cognitive development when they acquire the ability to take perspective, and no longer have egocentric thinking (a characteristic of the pre-operational stage). This change can be viewed as the result of developmental changes in information processing capacity. Information processing is a mechanism that is used across many different domains of cognitive functioning, and thus can be seen as a
domain-general mechanism.
Psychometric Theories of Intelligence Psychometric analysis of measurements of human cognitive abilities (intelligence) may suggest that there is a single underlying mechanism that impacts how humans learn. In the early 20th century,
Charles Spearman noticed that children's scores on different measures of cognitive abilities were positively correlated. Spearman believed that these correlations could be attributed to a general mental ability or process that is utilized across all cognitive tasks. Spearman labeled this general mental ability as the
g factor, and believed g could represent an individual's overall cognitive functioning. The presence of this g factor across different cognitive measures is well-established and uncontroversial in statistical research. It may be that this g factor highlights domain-general learning (cognitive mechanisms involved in all cognition), and that this general learning accounts for the positive correlations across seemingly different cognitive tasks. There currently is no consensus to what causes the positive correlations. 's
three stratum theory, an influential contemporary model of cognitive abilities. The broad abilities recognized by the model are fluid intelligence (Gf), crystallized intelligence (Gc), general memory and learning (Gy), broad visual perception (Gv), broad auditory perception (Gu), broad retrieval ability (Gr), broad cognitive speediness (Gs), and processing speed (Gt). Carroll regarded the broad abilities as different "flavors" of
g. Spearman's work was expanded upon by
Raymond B. Cattell, who broke g into two broad abilities: fluid intelligence (Gf) and crystallized intelligence (Gc). Cattell's student, John Horn, added additional broad abilities to Cattell's model of intelligence. In 1993, John B. Carroll added more specificity to Cattell and Horn's G
f-G
c model by adding a third layer of human intelligence factors. Carroll named these factors “narrow abilities”. Narrow abilities are described as abilities that do not correlate with skills outside their domain, following more along the lines of domain-specific learning theories. Despite breaking g into more specific areas, or domains of intelligence, Carroll maintained that a single general ability was essential to intelligence theories. This suggests that Carroll, to some extent, believed cognitive abilities were
domain-general. == Skills That May Be Acquired via Domain-General Mechanisms ==