Primary Mental Abilities

Primary Mental Abilities refer to 7 factors identified by Louis Leon Thurstone. These 7 factors, or primary mental abilities, are word fluency, verbal comprehension, spatial visualization, number facility, associative memory, reasoning, and perceptual speed. Some intelligence tests, such as the Wechsler Adult Intelligence Scale (WAIS), have sections that test for these 7 factors though they might have different names, e.g. perceptual speed is called processing speed on the WAIS.