In YIVO's first decades, Tcherikover headed the historical research section, which also included Simon Dubnow, Saul M. Ginsburg, Abraham Menes, and Jacob Shatzky. Leibush Lehrer (1887–1964) headed a section including psychologists and educators Abraham Golomb, H. S. Kasdan, and Abraham Aaron Roback. Jacob Lestschinsky (1876–1966) headed a section of economists and demographers Ben-Adir, Liebmann Hersch, and Moshe Shalit. Weinreich's language and literature section included Judah Leib Cahan, Alexander Harkavy, Judah A. Joffe, Zelig Kalmanovich, Shmuel Niger, Noach Pryłucki, and Zalman Reisen. YIVO also collected and preserved ethnographic materials under the direction of its Ethnographic Committee. In 1925, YIVO's honorary board of trustees or "Curatorium" consisted of Simon Dubnow, Albert Einstein, Sigmund Freud, Moses Gaster, Edward Sapir and Chaim Zhitlowsky.