Bouts of yawning and rapid open-and-close eye movement are often good indicators that we need a good night’s sleep. As we lay in bed and enter the different stages of sleep, we begin to have lucid or downright mysterious dreams that can leave us in utmost confusion in the morning. Chances are, if we remember these dreams, we’ll tell a friend to decipher their meaning, but our dream description can unveil a lot about our mental health. According to a recent study published in the journal Scientific Reports, dream analysis may reveal whether we’re psychotic or not, based on the speech patterns we use.

In the field of psychology and psychiatry, diagnosing patients is highly subjective and is largely based on qualitative observations rather than quantitative methods. This has triggered major controversy surrounding the publication of the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), because its recommendations did not make an effort to include biological evidence for diagnosis. Mauro Copelli, lead author of the study, and professor from the Department of Physics at the Federal University of Pernambuco (UFPE), aware of this ongoing problem, sought to rectify it, since the method lacks objectivity and most mental disorders have no biomarkers that can help psychiatrists diagnose them more accurately.

“Diagnosing psychotic symptoms is highly subjective,” said Copelli to Agência FAPESP. “That is why the most recent version of the Diagnostic and Statistical Manual of Mental Disorders [published by the American Psychiatric Association in 2013] came under so much fire.”

Since psychologists, such as Sigmund Freud suggested “dreams are the royal road to the unconscious,” in his 1899 book, The Interpretation of Dreams, Copelli and his colleagues, in conjunction with the Brain Institute of the Federal University of Rio Grande do Norte (UFRN) and the Research, Innovation and Dissemination Center for Neuromathematics (Neuromat) — one of the FAPESP Research, Innovation and Dissemination Centers — sought to examine whether the speech patterns in dream descriptions could help psychiatrists distinguish between schizophrenia and bipolar disorder. These two mental illnesses are of particular interest in the field of psychology because they are the most difficult to tell apart. Moreover, patients with these mental disorders often show common psychotic symptoms such as hallucinations, delirium, hyperactivity, and aggressive behavior, which can lead to a misdiagnosis.

The Brazilian researchers recruited a total of 60 people who were either healthy, schizophrenic, or bipolar. The participants were asked to recount a previous dream in which these responses would be transcribed and changed into word graphs. In panel A, each dot represents a word, and the dots are connected based on when the person spoke them. In panel B, schizophrenics and bipolar patients showed distinct word graphs from each other and the healthy controls.

Panels a and b
Photo courtesy of Scientific Reports. Scientific Reports

The findings revealed schizophrenic patients often discuss their dreams using very few words, while those with bipolar disorder tend to speak excessively and repeatedly, according to Business Insider. There were fewer connections seen in participants with schizophrenia, compared to the two other groups of participants, since they are not of many words. Bipolar patients, who tend to have a “flight of ideas,” described as a symptom in psychiatry, had a web of connections in the speech graphs.

The international scientists developed this relatively “simple and inexpensive technique” to serve as a tool for psychiatrists to make more accurate clinical diagnoses of patients with mental disorders. They hope this can be used not only for people with psychotic symptoms, but also those who may suffer from cognitive decline, such as dementia. The speech graphs can help analyze the language structure of these patients and can possibly be applied to the process of learning and developing speech and writing, says Natália Bezerra Mota, first author of the study, psychiatrist, and a doctoral candidate at UFRN.

Freud may have been ahead of his time after all, suggesting dreams do provide a road to the unconscious, which can reveal underlying pathologies that can be crucial for clinical use.

Source: Copelli M, Furtado R, Maia PPC, Mota NB, Ribeiro S. “Graph analysis of dream reports is especially informative about psychosis.” Scientific Reports. 2014.