On the development of procedural knowledge

Amnesic patients demonstrate by their performance on a serial reaction time task that they learned a repeating spatial sequence despite their lack of awareness of the repetition (Nissen & Bullemer, 1987). In the experiments reported here, we investigated this form of procedural learning in normal subjects. A subgroup of subjects showed substantial procedural learning of the sequence in the absence of explicit declarative knowledge of it. Their ability to generate the sequence was effectively at chance and showed no savings in learning. Additional amounts of training increased both procedural and declarative knowledge of the sequence. Development of knowledge in one system seems not to depend on knowledge in the other. Procedural learning in this situation is neither solely perceptual nor solely motor. The learning shows minimal transfer to a situation employing the same motor sequence.     

The development of scientific knowledge of the Earth

Investigation of children's knowledge of the Earth can reveal much about the origins, content and structure of scientific knowledge, and the processes of conceptual change and development. Vosniadou and Brewer (1992 , claim that children construct coherent mental models of a flat, flattened, or hollow Earth based on a framework theory and intuitive constraints of flatness and support. To examine this account, 62 children, aged 5–10 years, and 31 adults ranked 16 pictures according to how well they were thought to represent the Earth. Even young children showed scientific knowledge of the shape of the Earth. There was little or no evidence of naïve mental models, indicating that any intuitions or constraints must be very weak. Instead, before they acquire the scientific view, children's knowledge of the Earth appears to be incoherent and fragmented.     

On the development of knowledge during problem solving

A person might solve a problem progressing very quickly after an initial period of very little progress, as if new insight was suddenly gained, without that person possessing anything that merits being called insight. This is demonstrated in a series of studies as an extension of the experiments of Kotovsky and Simon (1990). A total of 68 undergraduate students solved an isomorph of the Chinese Ring Puzzle. The first study showed that the verbal protocols of participants thinking aloud contained accumulating explicit knowledge. In the second study, the participants' move records were analysed in a novel way, and it was shown that the choices of moves gradually improved. In the third study the knowledge about the puzzle was tested after the puzzle was solved. The participants demonstrated that they knew, although imperfectly, which move was possible in a given situation. The fourth study showed that verbalising did not alter problem solving profoundly. Together, the four studies demonstrated that solving the puzzle took place after a gradual development of knowledge, instead of a flash of insight.     

Occupational knowledge and career development in adolescence

In an effort to extend our knowledge of career development, two indices of career maturity were investigated in a sample of 6029 high school seniors sampled from 57 Texas public school districts. The study investigated both the degree to which late adolescents choose occupations whose educational requirements match their stated educational goals and the degree to which students' vocational interests are compatible with their occupational choices. The correlations between educational plans and educational requirements of the chosen occupations were .41 or less. Of the subjects who claimed to have at least considerable understanding of their first choice career, only about half planned to achieve the amount of education appropriate to enter that occupation. Subjects' perceptions of how well they understood their occupational choices were also negligibly related to the compatibility of their vocational interests and their career choices. Although educational understanding and interest compatibility both contribute to realism of occupational choices, the correlation between these two indices of career maturity accounted for less than 1% of the variance.     

The development of attribute dominance in the knowledge base

Two cuing, free-recall studies were conducted to test Bach and Underwood's (1970) hypothesis that acoustic encoding is dominant among second graders and semantic encoding is dominant among sixth graders. When retrieval cues were presented with to-be-remembered items at both input and output (Experiment 1), and when cues were presented only at output (Experiment 2), semantic cues were more efficient in elevating recall than were acoustic cues for both second and sixth graders. When these and other results generally found using recognition, sorting, incidental learning, and free-recall experimental designs are compared, it seems plausible that item presentation and memory-testing formats interact with age, and that these factors account for the different patterns of attribute dominance found in the literature. The knowledge base cannot be understood by focusing on either subject or task analyses, but only by focusing on interactions between subject and task variables as they change over time. The educational implications for young grade-school children are discussed.     

Partial knowledge in the development of number word understanding

A common measure of number word understanding is the give‐N task. Traditionally, to receive credit for understanding a number, N, children must understand that N does not apply to other set sizes (e.g. a child who gives three when asked for ‘three’ but also when asked for ‘four’ would not be credited with knowing ‘three’). However, it is possible that children who correctly provide the set size directly above their knower level but also provide that number for other number words (‘N + 1 givers’) may be in a partial, transitional knowledge state. In an integrative analysis including 191 preschoolers, subset knowers who correctly gave N + 1 at pretest performed better at posttest than did those who did not correctly give N + 1. This performance was not reflective of ‘full’ knowledge of N + 1, as N + 1 givers performed worse than traditionally coded knowers of that set size on separate measures of number word understanding within a given timepoint. Results support the idea of graded representations (Munakata, Trends in Cognitive Sciences, 5, 309–315, 2001.) in number word development and suggest traditional approaches to coding the give‐N task may not completely capture children's knowledge.     

Magnitude knowledge: the common core of numerical development

The integrated theory of numerical development posits that a central theme of numerical development from infancy to adulthood is progressive broadening of the types and ranges of numbers whose magnitudes are accurately represented. The process includes four overlapping trends: (1) representing increasingly precisely the magnitudes of non‐symbolic numbers, (2) connecting small symbolic numbers to their non‐symbolic referents, (3) extending understanding from smaller to larger whole numbers, and (4) accurately representing the magnitudes of rational numbers. The present review identifies substantial commonalities, as well as differences, in these four aspects of numerical development. With both whole and rational numbers, numerical magnitude knowledge is concurrently correlated with, longitudinally predictive of, and causally related to multiple aspects of mathematical understanding, including arithmetic and overall math achievement. Moreover, interventions focused on increasing numerical magnitude knowledge often generalize to other aspects of mathematics. The cognitive processes of association and analogy seem to play especially large roles in this development. Thus, acquisition of numerical magnitude knowledge can be seen as the common core of numerical development.     

The development of children's knowledge of alcohol and the role of drinking

Eighty children in kindergarten and grades 3, 6, and 8 were interviewed regarding their understanding of adult drinking and their knowledge of the rules of drinking. Understanding of adult drinking motives was assessed by asking them to interpret drinking episodes portrayed in brief vignettes. Their knowledge of drinking rules was inferred from answers to questions on where people drink, who can drink, how much is a lot to drink, and who decides the age of legal drinking. Children were also given a series of questions to assess their knowledge of physical causality. In addition, their parents were interviewed to determine their drinking frequency (in view of the children) and their attempts to talk with their children about drinking. The results indicated that children's understanding of adults' drinking motives followed closely a developmental model. Their motive scores were correlated with physical causality scores and, in the third grade, with their parents' drinking frequency. Girls' motive scores were significantly and consistently more mature than boys' scores. Furthermore, there was a significant relationship between children's stated intentions to drink and their parents' drinking frequency. The results are discussed in terms of the complexity of the concept of drinking; different dimensions have different developmental functions. Some aspects of drinking knowledge conform to other cognitive developmental phenomena (e.g., physical causality) while others are related to specific social context (e.g., parental drinking).     

Effects of knowledge and development on subordinate level categorization

Children and adults with high, moderate, and low levels of dinosaur knowledge were provided with a series of tasks to determine the relative effects of knowledge and development on subordinate category extension, differentiation, and subsequent revision. As knowledge increased, individuals generated higher proportions of category underextensions and lower proportions of overextensions. Adults, but not children, who were highly knowledgeable about dinosaurs demonstrated similar patterns of extension for unfamiliar categories, suggesting that knowledge transfer is mediated by age-related strategies. Adults at all levels of knowledge were more likely to revise their category extensions than children were. The relation between intelligence and expertise in object domains is considered and a preliminary model of the effects of knowledge and development on skill at categorization is presented.     

Event knowledge,elaborative propensity,and the development of learning proficiency

An experimental test was made of two hypotheses formulated to account for age differences across adolescence in the learning of arbitrary associations. One hypothesis ascribes such differences to two factors: the propensity to elaborate coherent relationships among initially disparate items, and accessibility to event knowledge that can form the bases of such relationships. The other hypothesis assumes that propensity remains constant across age, and that development stems entirely from increases in the accessibility of relevant event knowledge. These hypotheses are evaluated with reference to the performance of 11- and 17-year-olds in learning relationships among paired nouns. The results discredited both hypotheses, instigating the formulation of a revised conception of the relationship between knowledge and propensity as developmental determinants.     

The role of mutual knowledge in the development of perspective taking

Analysis of research on the development of perspective taking and social cognition leads to a new theoretical synthesis centered around the concept of mutual knowledge. Mutual knowledge is shared, and assumed by the knower to be shared, with other people. Attention to individual mental states, the usual subject matter of social-cognitive research, is necessary only in problematic interactions such as misunderstandings, deceptions, or other strategic interactions in which the ordinary assumption of mutual knowledge must be put aside. The present formulation is able to account for the structural transformations in social-cognitive development while retaining the processing capacity assumptions of the information-processing approaches.     

The classification of children's knowledge: development on the balance-scale and inclined-plane tasks

R.S. Siegler (1981, Monographs of the Society for Research in Child Development, 46 C2, Serial No. 189) has shown that performance on several Piagetian tasks is governed by similar rule structures. The purpose of the first study was to extend his analysis to the inclined-plane task, replicate his original observations about development on the balance-scale task, and determine the consistency in children's rule usage across tasks. We found that Siegler's (1981) binary decision representations adequately characterized development on these tasks, and there was fair correspondence of rule classifications across tasks. An alternative classification procedure, used to diagnose the rules of children who failed our original classification criteria, showed that most of these children's performance patterns were very similar to Siegler's rule patterns. In the second experiment, we improved the diagnosticity of our rule-assessment protocol in light of F. Wilkening and N. H. Anderson's (1982, Psychological Bulletin, 92, 215-237) criticisms, and observed that many Rule III children's predictions were associated with those of integration rules on both tasks. Despite these methodological improvements, many children, especially 5- to 7-year-olds, evidenced use of centration and lexicographic strategies, suggesting that these classifications are not simply an artifact of problem sampling. Some of the problems associated with the classification of children's knowledge are discussed.     

The development of ordinal numerical knowledge in infancy

A critical question in cognitive science concerns how numerical knowledge develops. One essential component of an adult concept of number is ordinality: the greater than and less than relationships between numbers. Here it is shown in two experiments that 11-month-old infants successfully discriminated, whereas 9-month-old infants failed to discriminate, sequences of numerosities that descended in numerical value from sequences that increased in numerical value. These results suggest that by 11 months of age infants possess the ability to appreciate the greater than and less than relations between numerical values but that this ability develops between 9 and 11 months of age. In an additional experiment 9-month-old infants succeeded at discriminating the ordinal direction of sequences that varied in the size of a single square rather than in number, suggesting that a capacity for non-numerical ordinal judgments may develop before a capacity for ordinal numerical judgments. These data raise many questions about how infants represent number and what happens between 9 and 11 months to support ordinal numerical judgments.     

Older adolescent females' knowledge of child development norms

This study, the first of three designed to investigate different age groups' knowledge of developmental norms of children, focused on older adolescent female university students. Data were collected from 280 midwestern university students through a questionnaire consisting of 16 items focusing on physical and social development of children from birth to three years of age. Results showed that knowledge of normal development was both over- and underestimated regardless of age of student or year in school. These findings are discussed within the context of the importance of knowledge of developmental norms for future parents.