2.4. Procedure
Participants first completed a short social and demographic
questionnaire which asked questions about their age, gender,
education (number of years in full-time education), and
occupation (the SOC2000, based on the UK's standard classification
of occupations; Rose & Pevalin, 2003). The younger group
was asked about their parents' occupations. They then completed
the tasks in the following order: Reaction Time Task
(a), Matrix Reasoning, Reaction Time Task (b), WTAR, Digit–
Symbol Coding, and Reaction Time Task (c). Note that there are
three reaction time tasks and that one is not reported here. The
order in which the different reaction time tasks were completed
was varied equally among the participants.