Mathematical difficulties have been distinguished as mathematics learning disability (MLD) and persistent low achievement (LA). Based on 1,880 Finnish children who were followed from kindergarten (age 6) to fourth grade, this study examined the early risk factors for MLD and LA. Distinct groups of MLD (6.0% of the sample) and LA (25.7%) children…

Mental abacus (MA) is a technique of performing fast, accurate arithmetic using a mental image of an abacus; experts exhibit astonishing calculation abilities. Over 3 years, 204 elementary school students (age range at outset: 5-7 years old) participated in a randomized, controlled trial to test whether MA expertise (a) can be acquired in standard…

Fundamental to amassing a lexicon of relational terms (i.e., verbs, prepositions) is the ability to abstract and categorize spatial relations such as a figure (e.g., "boy") moving along a path (e.g., "around" the barn). Three studies examine how infants learn to categorize path over changes in "manner," or how an action is performed (e.g., running…

Critically reviews literature relevant to the hypothesis that a major X-linked gene determines spatial ability in man. It is concluded that belief in the validity of the hypothesis is unfounded. (Author/SS)

Young and older nursery school children were taken to three locations in their school and asked to point to five targets on the school grounds. Older children were more accurate than younger children, but children's spatial representations were relatively nonintegrated at both age levels. Consistent sex differences in favor of males were found.…

Examines the ability of six- and eight-year-old children to hide and recover 20 marbles in a large room containing 100 possible sites. Shows that children tend to concentrate activities in sections of the room and are sensitive to clusters of proximal sites. (HOD)

Three studies, involving 72 3-month-old infants, demonstrated that infants remembered some of the original feature combinations of a mobile they had been trained to activate for up to 3 days but forgot all of them after 4 days. Even after 4 days, however, infants remembered the individual features that had entered into the original combinations.…

Examined the longitudinal predictability of spatial ability in late-adolescent females. No timing of puberty or lateralization effects were observed. These findings strengthen evidence that sex-related differences in spatial ability could be experientially determined and may help to focus the search for exactly how this occurs. (Author/GLR)

Examined children's recall of the spatial configurations of an environment after the children followed prearranged paths and encountered barriers to movement. When asked to reconstruct the environmental configuration from memory, males estimated distances more accurately than did females. No age differences were noted. (Author/DB)

Examined the relationship of environmental input to cognitive growth in language, spatial operations, concepts, and associative memory in children tested four times six months apart and differing in the amount of school input received. Found that children made greater growth over periods with greater amounts of school input for language, spatial…