In simple rule-switching tests, 3- and 4-year-olds can follow each of two sorting rules but sometimes make perseverative errors when switching. Older children make few errors but respond slowly when switching. These age-related changes might reflect the maturation of executive functions (e.g., inhibition). However, they might also reflect…

Representational theory of mind (RTM) development follows a universal developmental timetable whereby major advances in reasoning about mental representations occur between the ages of 3 and 5 years old. This progression appears to be only absent in the case of specific neurodevelopmental impairments, such as autism. Taken together, this suggests…