In his new version of intelligence testing, David Wechsler included new items that required nonverbal reasoning and discarded the intelligence quotient in favor of a new scoring system based on the normal distribution.

David Wechsler

David Wechsler was a psychologist who developed well-known intelligence scales, such as the Wechsler Adult Intelligence Scale (WAIS).

Intelligence Testing

The assessment of an individual's mental capabilities and cognitive functions through various standardized tests.

Normal Distribution

A bell-shaped curve that represents the distribution of many types of data where most occurrences take place in the middle of the range and fewer occur as you move away from the center.