Four new studies point to evidence that diversity can improve colleges students' critical thinking skills, according to the Chronicle of Higher Education on Monday.

The research, presented at the Association for the Study of Higher Education meeting in Las Vegas, found that students studied in various ways seemed to improve on standardized tests of critical thinking after coming into contact with students whose backgrounds differ from their own. And white students seemed to benefit the most.

The studies were largely focused on a pool of data in which students were measured using widely accepted critical theory tests at three points during their college careers, once before starting freshman year, once after completing freshman year, and once near the end of their senior year.

One of the studies, however, lead by Nicholas A. Bowman, an assistant professor of higher education and student affairs at Bowling Green State University, pointed out that the returns on critical thinking only occurred after repeated contact with students unlike themselves. After first contact with a student of a different background, Bowman warned, the measures of critical thinking actually go down because those encounters can reinforce long-held stereotypes. After "two or more" encounters, the rise in critical thinking increases rapidly.

"College diversity interactions only lead to educational benefits when these experiences occur frequently," he wrote in the paper, according to the Chronicle.

This comes as the Supreme Court is set to weigh in on the constitutionality of affirmative action in higher education admissions in Fisher v. University of Texas at Austin, which will determine if the state can use race as one factor in determining whether a student may be admitted.