David Rosenhan in 1973

David Rosenhan and his volunteers feigned symptoms to be admitted to psychiatric hospitals.Credit: Denver Post via Getty

The Great Pretender: The Undercover Mission that Changed our Understanding of Madness Susannah Cahalan Grand Central Publishing (2019)

From 1969 to 1972, an extraordinary experiment played out in 12 psychiatric institutions across 5 US states. Eight healthy people — including David Rosenhan, a social psychologist at Stanford University in California, who ran the experiment — convinced psychiatrists that they needed to be committed to mental hospitals. The ensuing paper, published in Science in 1973, opens with the words: “If sanity and insanity exist, how shall we know them?” It claimed that the psychiatric establishment was unable to distinguish between the two.

Rosenhan’s study had far-reaching and much-needed effects on psychiatric care in the United States and elsewhere. By the 1980s, most psychology textbooks were quoting it. It also influenced society more widely, and not always positively: in the law courts, for instance, it undermined the value of expert testimonies from psychiatrists. Now, in The Great Pretender, journalist Susannah Cahalan turns a fresh, critical eye on the experiment and the shockwaves it sent through the field and beyond.

Cahalan quotes a former colleague of Rosenhan’s, who notes that he was a good networker, an excellent lecturer and a generally charismatic character. “But some people in the department called him a bullshitter,” Kenneth Gergen says. And through her deeply researched study, Cahalan seems inclined to agree with them. She discovered that the man whom she had initially admired, and who had done so much to change how mental illness was perceived, was not all that he had seemed. And neither, she argues, was his famous experiment.

Cahalan began her investigation into Rosenhan’s experiment in good faith. Ten years ago, she developed paranoia, hallucinations and, eventually, seizures. She was dosed with antipsychotics before being correctly diagnosed with a very rare type of autoimmune encephalitis, an ordeal she describes in her first book, Brain On Fire.

After it was published in 2012, a casual conversation with McLean Hospital psychiatrists in Boston, Massachusetts, alerted Cahalan to Rosenhan’s experiment. She immediately wanted to know more — about the experiences of those who volunteered, and the challenges that such a risk-laden experiment would have posed decades ago.

Rosenhan was not the first to infiltrate a psychiatric hospital and report on conditions. Cahalan tells, for example, of the nineteenth-century journalist Nellie Bly, who deceived doctors to spend ten days in an overcrowded women’s asylum on Blackwell’s Island, New York. Bly’s reports of the appalling conditions there shamed politicians into increasing the asylum’s budget.

But Rosenhan was the first to carry out a formal experiment involving a number of “pseudopatients”. All eight, including Rosenhan, reported the same symptom to different doctors: that they heard voices uttering “thud, empty, hollow”, denoting existential doom. Seven were diagnosed with schizophrenia; one with manic depression. Once admitted to hospital, the volunteers stopped simulating symptoms of abnormality. Rosenhan noted in the Science paper that genuine patients often realized that the pseudopatients did not have a mental-health disorder, and accused them of being undercover journalists or academics checking up on the hospital. Psychiatrists seemed less perceptive: it was several weeks before some of the pseudopatients got discharged.

Although Rosenhan died in 2012, Cahalan easily tracked down his archives, held by social psychologist Lee Ross, his friend and colleague at Stanford. They included the first 200 pages of Rosenhan’s unfinished draft of a book about the experiment.

At first, it seemed that Cahalan’s research was going to be easy, even though Rosenhan had given fictitious names to the pseudopatients she wished to track down, along with the hospitals they went to. Ross warned her that Rosenhan had been secretive. As her attempts to identify the pseudonymous pseudopatients hit one dead end after the other, she realized Ross’s prescience.

The archives did allow Cahalan to piece together the beginnings of the experiment in 1969, when Rosenhan was teaching psychology at Swarthmore College in Pennsylvania. The students complained that the course was too abstract, so Rosenhan suggested that they check into a psychiatric hospital to get to know people with schizophrenia personally. The superintendent of the local Haverford State Hospital was willing to take them on, but Rosenhan cautiously decided to check things out for himself first. He emerged humbled from nine traumatizing days in a locked ward, and abandoned the idea of putting students through the experience. But it set him thinking about a scientific experiment aimed at exposing the system’s travesties.

According to Rosenhan’s draft, it was at a conference dinner that he met his first recruits: a recently retired psychiatrist and his psychologist wife. The psychiatrist’s sister also signed up. But the draft didn’t explain how, when and why subsequent recruits signed up.

Cahalan interviewed numerous people who had known Rosenhan personally or indirectly. She also chased down the medical records of individuals whom she suspected could have been involved in the experiment, and spoke with their families and friends. But her sleuthing brought her to only one participant, a former Stanford graduate student called Bill Underwood.

Underwood and his wife were happy to talk, but two of their comments jarred. Rosenhan’s draft described how he prepared his volunteers very carefully, over weeks. Underwood, however, remembered only brief guidance on how to avoid swallowing medication by hiding pills in his cheek. His wife recalled Rosenhan telling her that he had prepared writs of habeas corpus for each pseudopatient, in case an institution would not discharge them. But Cahalan had already worked out that that wasn’t so.

Comparing the Science report with documents in Rosenhan’s archives, she also noted many mismatches in numbers. For instance, Rosenhan’s draft, and the Science paper, stated that Underwood had spent seven days in a hospital with 8,000 patients, whereas he spent eight days in a hospital with 1,500 patients.

When all of the leads from her contacts led to ground, she published a commentary in The Lancet Psychiatry asking for help in finding them — to no avail. Had Rosenhan invented them, she found herself asking?

In recent years, other heroes of social psychology have been found to have misrepresented their data. The most prominent case is that of Dutch social psychologist Diederik Stapel, who was forced to retract 58 papers. Those who have followed these cases might be appalled by the Rosenhan story, but will not be surprised.

Cahalan, whose life was saved by front-line medical science in the context of psychiatry, was shocked by what she found. She writes that she cannot be completely certain that Rosenhan cheated. But she is confident enough to call her engrossing, dismaying book The Great Pretender.