At first glance, the link between photonics and psychiatry might not seem obvious. But, Pierre Marquet knows bringing these two disciplines together could help prevent psychiatric disorders in at-risk children.
“It is true there is a big gap between the disciplines,” says Marquet. “In fact, the challenge is not so much to combine them, but to develop new, cutting-edge technologies dedicated to a brand new field: neurophotonics.”
Marquet is the Canada Excellence Research Chair in Neurophotonics at the Université Laval. He comes to Quebec City from Switzerland, where he was director of a psychiatric neurosciences research unit at the University Hospital of Lausanne, as well as in charge of the hospital’s specialized section for treating mood and personality disorders.
He stresses that treatments currently available for major psychiatric disorders such as schizophrenia, bipolar disorders and major depression are “largely insufficient.” He believes one barrier to significant advancements in treatment is the lack of proper tools to identify biomarkers. This identification would help guide early diagnosis, and ensure that at-risk children are monitored.
Psychiatric disorders are illnesses for which we have practically no reliable biomarkers right now.
“I believe that, if we could detect a serious psychiatric disorder earlier, it is a good bet we would be able to improve the disease’s evolution for the sufferer,” he says.
While spectacular advances in neuroimaging (such as MRIs and PET scans) have given us a glimpse at relationships between our psyche and brain, the discrete brain changes that accompany changes in a person’s mental state are still hard to detect. Marquet, however, believes that “multimodal approaches,” combining existing brain-imaging tools with new—particularly, optical—techniques, could help drastically improve detection of these discrete brain changes. That would lead to earlier diagnosis—perhaps even before any disabling clinical symptoms appear. Such tools would also help doctors follow a disease’s progression in a patient.
“Advanced photonics or optics techniques can be of great help,” says Marquet. “We can, in combination with an MRI, use noninvasive techniques, such as near infrared spectroscopy, to study in detail the complex structural and functional organization of our brain [and] help identify and understand the complex neurobiological processes, in their early stages, that will slowly and significantly alter brain function and lead to the appearance of psychiatric disorders.”
Marquet is working to identify what he calls “new vulnerability biomarkers” (or indicators) of future psychiatric disease—especially in children from families where one or both parents suffer from a psychiatric disorder, since they are more at risk of developing a mental disorder later in life, as young adults.
“Psychiatric disorders are illnesses for which we have practically no reliable biomarkers right now,” says Marquet. “In contrast, for somatic illnesses like cancer or diabetes, you can often detect the illness early and follow its evolution, thanks, specifically, to biomarkers. The earlier we detect it, the better the chance there is of treating the disease—or, at least, of drastically improving its prognosis.”
The idea that major psychiatric disorders have biological determinants that are present in childhood has only recently gained acceptance. Marquet believes studying the dynamics of neuronal cells from patients and their children will make it possible to identify new cellular biomarkers of vulnerability for psychiatric illnesses.