The Secret Twin Study: Files Sealed Until 2065

The Secret Twin Study: Files Sealed Until 2065

From Conspiracy Theories by Spotify Studios

April 15, 2026 · 51 min

About this episode

The episode explores the controversial twin study hidden for decades and features expert Dr. Nancy Segal.

Does nature or nurture shape who we are? Does our personality come from our genes, or the environment we live in? Countless scientific studies on the subject have been published. But one such study – a collaboration between a psychoanalyst and a New York adoption agency – was instead hidden away for decades. Could it be because the study was founded on lies? Because it was unethical? Or might there be some other secrets hiding in the files of Dr. Peter Neubauer? Today, we welcome a special guest: twin studies expert Dr. Nancy Segal. Check out her book! Deliberately Divided: Inside the Controversial Study of Twins and Triplets Adopted Apart Help us reach 10k followers on Instagram! @⁠theconspiracypod⁠ Learn more about your ad choices. Visit podcastchoices.com/adchoices

People in this episode

Guest: Dr Nancy Segal

Topics covered

  • nature vs nurture
  • twin studies
  • psychology
  • ethics in research

Keywords

  • Peter Neubauer
  • adoption
  • scientific studies
  • controversy

Mentioned in this episode

Products: Deliberately Divided: Inside the Controversial Study of Twins and Triplets Adopted Apart

Books & works: Deliberately Divided: Inside the Controversial Study of Twins and Triplets Adopted Apart Help

Places: New York

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