Whose research on the negative effects of school segregation on African American children was cited by the United States Supreme Court when it overturned the ""separate but equal"" school doctrine in 1954?

The Clark's doll test study

Explanation:

Studies by Dr. Kenneth and Mamie Clark in the 1940s which was known as the doll test was cited by the Supreme Court in the decision which overturned  separate but equal doctrine which was established in 1954 in the case of Plessy v. Ferguson.

The doll test was aimed at studying the psychological effect of segregation on African American children in which children between the ages of 3 to 7 were asked to identify the dolls they preferred and majority of them picked the white and attributed good qualities to it.

During the case between Brown and the Board of Education of Topeka, this experiment was cited by the Supreme Court in delivering their verdicts in favour of Brown prohibited segregation of black children in the education system.

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