Many explanations have been proposed for the evolution of our anomalously large brains, including social, ecological, and epiphenomenal hypotheses. Recently, an additional hypothesis has emerged, suggesting that advanced cognition and, by inference, increases in brain size, have been driven over evolutionary time by the need to deal with…

The essay integrates the psychometric intelligence approach with the cognitive-developmental approach or the stage theory erected by Piaget and his disciples. The latter led to Piagetian Cross-Cultural Psychology and the accumulation of an immense body of data. It shows that different IQ levels are indicative of the peculiar stages of cognitive…

The current study tests if the type of children's daily main meal (slow versus fast food) mediates the association of socioeconomic status (SES) with cognitive ability and cognitive growth in childhood. A Scottish birth cohort (Growing Up in Scotland) was assessed at ages 3 (N = 4512) and 5 years (N = 3833) on cognitive ability (i.e. vocabulary…

Sex differences in the latent general and broad cognitive abilities underlying the Woodcock-Johnson Tests of Cognitive Abilities were investigated for children, youth, and adults ages 6 through 59. A developmental, multiple indicator-multiple cause, structural equation model was used to investigate sex differences in latent cognitive abilities as…

The association between intelligence and diet at 3.5 and 7 years was examined in 591 children of European descent. Approximately half of the children were born small-for-gestational age (birth weight @?10th percentile). The relationship between IQ and diet (measured by food frequency) was investigated using multiple regression analyses. Eating…

An approach to intelligence which emphasizes domain-specific constraints on knowledge structures is compared to information processing approaches. The evaluation of any cognitive ability as being intelligent crucially depends on prior specification of the formal constraints on the domains of knowledge from which that ability originates. (Author/RD)

A reanalysis of Stephens' intercorrelations of Wechsler subtests, achievement tests, and Piagetian tasks was conducted. (EJ 055 112) Piagetian tasks contributed almost equally to the definition of the general factor in intelligence along with the Wechsler subtests and the achievement tests. Communality outweighed differences between intelligence…

To study age-related improvements in information processing, a release from proactive interference (PI) procedure was used with 144 children in conjunction with a running memory task. For class of item and acoustic similarity, evidence was found for PI release with age, but there was no evidence of a relationship between short-term memory (STM)…

Based on the construct of classical IQ, a model of the proportions of the population at various stages of cognitive development as a function of age is proposed. The model compares well with other theoretical models and provides evidence of the salience of the construct of general cognitive capacity. (SLD)

Memory-based searching was compared in 15 developmentally delayed and 24 normal two-year-olds. In a relatively easy memory task, individual differences were minimal, but searching for a plausible alternative location based on memory revealed marked individual differences and an important difference in the cognitive functioning of the delayed…

Do stage-related patterns of early cognitive development reported for normally developing children also characterize at-risk and handicapped children when mental age organization of data is used? Mental age predicted Piagetian-based cognitive levels one to three but did not predict highest-level symbolic functioning in 95 handicapped children.…

Available from: Ablex Publishing Corporation, 355 Chestnut Street, Norwood, New Jersey 07648. Two groups (high and low functioning) of educable mentally handicapped children consisting of 70 Ss' average age 127 months' were tested for strategies in their approach to memory and problem solving tasks and for their responsiveness to strategy…

The degree to which reading ability and intelligence, as measured by the Raven Progressive Matrices Test, were related was studied for 486 students in grades 2 through 12 in a small town, rural school system. Results indicate the strong and consistent relationship between general intelligence and reading ability. (SLD)

Change in cognitive functioning is an important aspect of human aging and a key outcome in many medical conditions. However, cognitive change can rarely be measured directly, since prior cognitive data do not exist for most people. We examined the criterion validity and one-year stability of the difference between National Adult Reading Test…