This study compared the regulation of cognitive activity in 30 children (ages 15 to 95 months) with autism or mental retardation matched for global, verbal, and nonverbal developmental ages. Testing on tasks of object permanence indicated that the autistic children had a pervasive difficulty in maintenance set, made more perseverative errors, and…

Nine- to 18-month-old infants were presented with simple two-location manual search tasks involving invisible displacements of objects with sequence of displacements occurring before infants search. Results provided insights into age differences associated with development of logical search strategies, information-processing skills, and temporal…