To test mental reaction time the tester will use a stop watch and ask this question. ' How old is someone born in 1943? Then the questioner will time the length of the response and distribute it...
Some examples are the MMPI (Minnesota Multiphasic Personality Inventory), MBTI (Myers-Briggs Type Indicator), SLOAN/Big 5 personality test, and the MCMI (Millon Clinical Multiaxial Inventory).