The study by Shanahan et al. utilized a variety of measures to assess processing speed. These included linguistic measures such as rapid automatized naming (RAN) and the Stroop test as well as non-linguistic mea- sures such as the WISC Coding subtest, the Trailmaking test and the Stop-Signal task. Findings indicated that, despite their differences, these various measures of pro- cessing speed were highly correlated with one another, all apparently reflecting a common factor that contrib- utes to both ADHD and Reading Disorder.