Many tests which attempt to produce intelligence quotient or mental age scores for children rely on time taken to complete the task for a valid result to be obtained. A number of tests were carried out with both Down's Syndrome and normal children (128 Down's Syndrome; 162 normal) in order to determine (1) relative abilities to complete the tasks…

This study examines the effects of sex, socioeconomic status, birth order and birth spacing on the cognitive performance of 12-week-old infants. A brief review of research on neonatal cognitive ability is followed by a description of the study itself. The subjects, 189 three-month-old Caucasian infants (61 first borns, 58 second borns, and 49…