Series consists of a drawer of catalogue cards with information concerning most MNI Fellows from between the institute's opening to the 1970s. Much of this information consists of mailing addresses which were compiled in the late 1970s and early 1980s, and is thus likely no longer accurate. Many of the cards are also accompanied by photographs of the particular Fellow.

This series consists of most of Dr. Penfield's correspondence. The series is composed of three sub-series corresponding to Dr. Penfield's "Simple System." (C = Correspondence)

This series includes records of events, biographical and historical data, and many visual materials. Much of this material is ephemeral and was originally found in Dr. Penfield and Mrs. Penfield's boxes of memorabilia. The series is divided into 15 subseries, each of which may be grouped into two divisions: general and personal (indicated by addition of WGP to file identifier).

This series consists of objects or artifacts that belonged to Dr. Penfield.

Series consists of newspaper and magazine article clippings collected by Dr. Penfield.

Series consists of reports and notes collected and produced by Dr. Penfield as part of his work on committees of the National Research Council of Canada during the Second World War. The documents found in the series include American, British, and Canadian reports on different kinds of medical tests, as well as committee meeting minutes. (WP-CTEE = Wilder Penfield - Committees)

This series contains the final drafts of Dr. Penfield's various published books.

Series consists of notes produced by Dr. Penfield on books and articles he had read.

Series consists of miscellaneous material produced and collected by Dr. Penfield. This series includes art work, notes, and correspondence, as well as Dr. Penfield's academic robes and hats. This includes copies of the French 'Bulletin de l'Académie Royale de medecine', 'Bulletin de l'Académie nationale de medecine' and 3 editions of the Montreal La Lancette Canadienne journal. The series also includes less than 1 cm of photographs (found in file J 13-1), a framed diploma (file J 2-3) and selections for an exhibit from 1991 by William Feindel.