Background: Allelic variation in the promoter region of a gene that encodes tryptophan hydroxylase isoform 2 (TPH2), a rate-limiting enzyme of serotonin synthesis in the central nervous system, has been associated with variations in cognitive function and vulnerability to affective spectrum disorders. Little is known about the effects of this gene…

An account of studies conducted by author and others concerning Piaget's view of object concept development in infants. (HS)

Three children were observed in their homes approximately once a month for one year, from their 11th through 22nd month of life. Based on observation of the children's changing nonverbal behaviors, a five-level developmental sequence documenting the evolution of the cognitive notion of agent was developed. (Author)

Two experiments investigated 8-, 10-, and 12-month-old infants' levels of searching for mothers, strangers, and objects. Found that, overall, 10- and 12-month-old infants had higher levels of searching for mothers, whereas youngest infants showed no differences for searching. This discrepancy is likely due to social cognitive development and…

Maintains that Muller and Overton (1998) challenge the current Zeitgeist regarding infant cognitive development. Suggests that researchers reconsider infants as developing actors in a meaningful environment, not as born philosophers. Notes the need to explore processes underlying key transitions in infancy and the relation between action and…

Finds that the object concept scores of 104 infants were relatively independent of IQ and background variables, showing that object concept is the most stable developing function in infants and an accurate reflection of infant cognitive potential. (RL)

Nine experiments examined 6- to 10-month-olds' formation of an abstract category representation for "between." Findings indicated that older, but not younger infants, could form an abstract category representation for "between" when performing in an object-variation version of the between categorization task. Six- to…

This paper is a response to a review of the conference titled, "Unintegration, Disintegration and Integration", written by Cathy Urwin and Maria Rhode in the ACP Bulletin. The review mentioned Michael Fordham, noting that he referred to a "good" kind of unintegration. In this paper, I point out that this is a somewhat misleading reference to what…

Some of the findings of a longitudinal study of three infants between their 11th and 22nd months to document development of linguistic expression of the agent concept indicated that first vocalizations were inconsistently associated with nonverbal agentive behaviors and later mature utterances coded agent-action-recipient events. (MC)

Evaluates the degree to which the social-referencing perspective provides a valid explanation of some features of infant behavior. (MP)

Presents a study of the development of self-recognition in infants from 6 to 24 months of age. The development of self-recognition is compared to the development of object permanence. (BD)

Presents a study of decalage between object permanence and person permanence. Decalage was influenced by environmental as well as stimulus factors with infants tested between 6- and 81/4-months/of-age. (BD)

Two experiments examined development of the ordinality concept in infants. Found that 11-month-olds successfully discriminated, whereas 9-month-olds failed to discriminate sequences that descended in numerical value from sequences increasing in numerical value. Nine-month-olds could discriminate the ordinal direction of sequences that varied in…

A case study of the period of repetitive babbling in one Dutch infant is reported. Repetitive babbling is seen as a systematic and continuous process, during which the child is applying certain strategies in order to form concepts concerning the possibilities of his or her articulatory apparatus. Strategies identified are: (1) variation…

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.…