A professor has been testing the brains of people who say they’ve experienced a UFO encounter — and these are the symptoms they display.

Dr. Garry Nolan, a Professor of Pathology at Stanford University who has published more than 300 research articles and holds 40 US patents, has spent the past decade analyzing materials from alleged Unidentified Aerial Phenomenon (UAP).

Speaking to Vice’s Motherboard, Nolan opened up about his work and revealed what sparked his interest in UAP.

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