Over the years, in what became a rite of passage, Yale students would break in—by unscrewing a door panel and squeezing inside—to a room in the basement of Harkness Dormitory. It is a daunting trek, dimly lit, beneath oversized heating and ventilation ducts and through spaces that haven’t seen a broom or mop in years. The students came to see the brains. Hundreds were lined up on dusty metal shelves, submerged in cloudy formaldehyde, their gray matter crumbling at the edges. Since the mid-1990s and continuing to this day, students paid their respects by signing a poster in the room, thereby becoming members of the “Brain Society.”

“The pledge on the poster was ‘Take Only Memories,’ ” said Terry Dagradi, a photographer at the medical school who has been working on the preservation and cataloging of the collection’s archive of patient photographs.

The brains belonged to patients of Harvey Cushing, M.D., the pioneering neurosurgeon, who preserved them as part of his tumor registry and left them to Yale upon his death in 1939. In storage since the 1950s, they are about to come to light again. During the 1990s Christopher Wahl, M.D. ’96, wrote his thesis on the collection, bringing new attention to the Cushing brains. Now, under the direction of Dennis D. Spencer, M.D., HS ’76, chair and Harvey and Kate Cushing Professor of Neurosurgery, the collection is being restored and moved to a “brain library” within the medical library. The Cushing Center, designed by architect Turner Brooks, will display all 550 brains in jars. Some will be shown alongside Cushing’s meticulous medical records and striking photographs of patients. “I don’t know of another library that has a collection of autopsied preserved brains as their primary holdings,” said Spencer.

When he began the project in 2005, much of the brains’ formaldehyde had partly evaporated long ago, and what remained was dirty. The jars had leaky seals and were coated in filth. Nicole St. Pierre, who holds a degree in forensic science and will soon begin training as a physician associate, is cleaning them and replacing the preservative. Dagradi and others will coordinate the displays. The Cushing Center will open on June 5, with Kate Cushing, Harvey Cushing’s granddaughter, taking part in the ribbon cutting.

Perhaps the most famous brain in the collection belonged to a well-known figure of the early 1900s: Major General Leonard Wood, M.D. A physician and friend of Theodore Roosevelt, he led the Rough Riders’ charge up San Juan Hill, and was governor of Cuba and the Philippines. In 1904, in his 40s, Wood suffered seizures in his left leg. For a time, he treated them by sniffing chloroform. But after a few years the seizures and a growing lump on his skull could no longer be ignored. Cushing agreed to operate, though no one at the time had much experience in removing brain tumors. In a groundbreaking 1910 operation at Johns Hopkins, Cushing removed a large benign growth; it proved to be a meningioma, a tumor of the lining of the brain. Wood was cured of his seizures and resumed his active life, which included service as Army chief of staff and a candidacy for the Republican presidential nomination in 1920.

The success of the operation so impressed a group of Harvard physicians that they invited Cushing to relocate to the brand-new Peter Bent Brigham Hospital in Boston. He agreed and went on to become the father of neurosurgery.

But Wood’s tumor recurred, forcing him to return from the Philippines in 1927. Cushing, by now far more experienced, operated again, and found a second meningioma almost twice the size of the first. After a difficult operation and much blood loss it was removed and the patient appeared to be recovering. A few hours later, though, Wood became unresponsive and died. Cushing autopsied him and found the ventricles of the brain filled with blood. Devastated, he preserved both brain and tumor and wrote up the case in his 1938 textbook, Meningiomas, which he co-authored with neuropathologist Louise Eisenhardt, M.D. With customary precision and candor, he blamed himself for failures of surgical judgment. He retired five years later.

“It’s amazing how these two men’s careers were so much in parallel,” said Spencer. “They crossed at the beginning of their careers and again at the end.”

Spencer and St. Pierre recently re-autopsied Wood’s brain to learn more about his death; Spencer had suspected that a bleeding vessel from the tumor was the culprit. But he could find none, and he now thinks the primitive blood transfusion practices of the day may have disturbed Wood’s clotting mechanisms and led to the deadly bleed.

It was postmortem examinations like these that made the Cushing brains such an important resource. Before imaging technology was available, surgeons and pathologists studied gross specimens to see damage wrought by strokes, tumors, or injuries. But few brains are saved today, since autopsies are falling out of favor—CT and MRI are the preferred teaching tools. Yet even though they’re not used for didactic purposes, said Spencer, the brains are “beautiful and historic.” And as the students knew, they make an impressive sight. Alongside Cushing’s detailed writings and photographs, they embody memories of neurosurgery’s pioneering era.