BY THE EARLY 1930S, EGAS MONIZ had already left his mark on the treatment of the human brain. His method of cerebral angiography allowed physicians to observe cranial blood flow for the first time. But on November 12, 1935, the Portuguese neurologist would attempt something more audacious: a surgery to relieve the suffering caused by severe mental disorders.

His patient was a 63-year-old woman suffering from hallucinations, severe anxiety and crying spells, insomnia and paranoia (she believed her pharmacist and physician were trying to poison her).  Few effective treatments were available for psychiatric patients at the time. Moniz believed that mental disorders were caused by “fixed thoughts” brought on by problems in nerve pathways in the brain’s frontal lobes.  Because his hands were distorted by gout, he enlisted his colleague Almeida Lima to assist him with the experimental operation. Lima drilled holes on each side of the woman’s head, inserted a syringe and injected the prefrontal lobe of her brain with pure alcohol, rendering it permanently useless.

A few months after the procedure, a psychiatrist who examined the patient noted that she still seemed somewhat sad, but that her anxiety and paranoia had decreased significantly. The operation, deemed a success, came to be called a lobotomy.

Doctors had been drilling holes in skulls since antiquity to try to ease mental pain. A practice called trepanning was used to treat both head trauma and psychiatric pain by releasing evil spirits. While Moniz coined the term “psychosurgery,” several other doctors had also attempted such operations in the twentieth century, according to neuroscience historian Elliot S. Valenstein in Great and Desperate Cures: The Rise and Decline of Psychosurgery and Other Radical Treatments for Mental Illness.   When Moniz published data describing his success treating a series of 20 patients in 1936, the medical world took notice.

Valenstein questions Moniz’s evidence that he cured many of the patients. But overcrowding in U.S. mental institutions made psychiatrists desperate for new treatments, and the lobotomy quickly became part of mainstream medicine. By one estimate, 60,000 lobotomies were performed in the United States between 1936 and 1956 on patients with a variety of diagnoses, such as depression and schizophrenia. Walter J. Freeman, a neurologist at George Washington University, became the procedure’s most enthusiastic practitioner. Freeman eventually developed his own version, the transorbital lobotomy, in which he inserted an ice pick into the brain by way of the patient’s eye socket, then pounded the tool with a mallet, rocking it back and forth to sever nerve fibers.

Moniz received the Nobel prize in Physiology or Medicine in 1949 for developing the lobotomy. While acknowledging that the award seems controversial today, the official website of the Nobel prize defends the honor, noting that Moniz’s innovation offered a treatment for the mentally ill when no other options were available. Some patients did benefit from the procedure, recovering from previously untreatable depression, anxiety and other conditions.   Yet complications included profound apathy, childish or uninhibited behavior and epilepsy. Freeman’s own records suggest that lobotomies killed or worsened the conditions of 14 percent of patients.

The arrival of psychiatric drugs helped push lobotomies out of favor by the 1960s. (The alarming depiction of the procedure in Ken Kesey’s 1962 novel One Flew Over the Cuckoo’s Nest further soured the procedure’s reputation.) But neurosurgery for psychiatric disorders did not disappear completely. In a cingulotomy, radio waves are used to destroy brain tissue, which can benefit some patients with intractable depression, obsessive-compulsive disorder or other psychiatric disorders. However only a small number of these are performed every year, and the checkered history of psychosurgery has yet to find a robust new chapter.