More than a century after legendary ballet dancer Vaslav Nijinsky penned a diary in a state of psychosis, McGill University researchers have mined the pages to learn more about how mental illness can affect language.
Nijinsky was once considered among the world's greatest dancers, but his career ended abruptly after the onset of psychosis in 1918. A diary he filled with intensely personal reflections was saved by his wife and initially published in an edited form. Only recently did a version much closer to the original become available.
For Alban Voppel, Assistant Professor of AI and Psychiatry at McGill, the diary presented a rare opportunity.
"Language provides a window into someone's mind," said Voppel, the study’s last author and a researcher at the Douglas Research Centre. "Complete book-length texts written during an active psychotic episode are quite rare, giving us a unique opportunity to study language as the illness was unfolding.”
Researchers applied computational language-analysis tools to measure patterns in word use and structure in the diary. They then applied those tools to a text written by Nijinsky's wife, so as to have a point of comparison from the same historical and social context.
The findings , published Medical Humanities, challenge a common assumption about psychosis.
“Nijinsky’s writing was not simply ‘chaotic,' as one might expect from psychosis or thought disorder,” said Voppel.
Instead, the writing displayed a form of repetitive thinking that seemed coherent on the surface but relied on an unusually narrow and repetitive vocabulary.
"It's sort of a fake coherence, a mechanical coherence," Voppel said. "He came back to the same topics and used a lot of the same words, especially 'I,' 'God' and 'love.'"
The findings suggest psychosis can affect language at different levels. A person may retain a broad narrative structure while becoming increasingly restricted in the words and ideas they use.
The next step is to test the findings against modern writing samples to determine whether they reflect a broader linguistic signature of psychosis. Ultimately, the work could contribute to AI-powered tools that help psychiatrists detect subtle clues to mental illness in language and track how symptoms evolve over time.
“ Writing when writhing with psychosis: a computational linguistic autopsy of Vaslav Nijinsky's diary” by Lena Palaniyappan and Alban Voppel et al., was published in Medical Humanities. The research was supported by the Monique H. Bourgeois Chair in Developmental Disorders, the Graham Boeckh Foundation, the Fonds de recherche du Québec-Santé and the Wellcome Trust.
Medical Humanities
Writing when writhing with psychosis: a computational linguistic autopsy of Vaslav Nijinsky's diary
21-Aug-2026