Through a groundbreaking investigation into the link between disrupted sleep and depression, greater understanding of mental illness – alongside the potential to develop new treatments – is becoming closer every day.
By investigating the flow of cerebrospinal fluid (CSF) during sleep – which is essential for removing metabolic waste products from the brain – the new research project aims to learn more about its role in causing depression.
The first-of-its-kind study, led by Dr Laura Lewis of Boston University, will examine the impact of the waves of CSF known to flow through the brain during sleep, and how that is affected by disturbances to sleep.
The project – Linking Sleep, CSF Flow and Inflammation in Depression – hypothesises that sleep disruption could contribute to depression by reducing CSF flow in the brain. This idea has not yet been tested.
It will use methods for fast MRI imaging, pioneered in Boston, to make new measurements of brain fluid flow.
The outcome of the two-year study – which has secured an Inaugural Trailblazer Research Award Fellowship from the 1907 Foundation – will investigate “an entirely new direction in depression research”, says Dr Lewis.
“We know sleep is important in mental health and it is linked to the emergence of depression, but we wanted to understand if what might be happening during sleep may be one of the causes of depression,” she says.
“The mechanism by which chronic sleep disruption might contribute to inflammation and depression is not yet well understood, but studying CSF flow in psychiatric disorders is a new conceptual direction. No studies on CSF flow waves in depression currently exist.
“We are bringing in new types of advanced imaging to look at the fluid flow; we know there are waves in the brain but we don’t know what they do.
“We don’t know what we are going to find, it’s very novel and exploratory, but we will look at the different consequences of not sleeping long enough and how that could contribute to depression; maybe some people sleep for too long; maybe the sleep is not restorative.
“My deep interest is why sleep is so critical to brain health, it has very wide-ranging consequences to how we feel and think, and our goal is to better understand what sleep does. It could be a guide for potential future interventions.
“Whatever we find here will hopefully be valuable new information toward the ultimate goal of developing treatments for people with mental illness.”
With increasingly-advanced techniques in neuroimaging and fMRI becoming available – with Dr Lewis collaborating with imaging partners including the world-leading Athinoula A. Martinos Center for Biomedical Imaging – the scientists can track faster changes in brain activity and fluid flow.
“We can see through the MRI scanner the blood and CSF in the brain, how the fluid flows in waves, how it cushions and protects the brain, and how the fluid is moving. We’re bringing together imaging techniques to do that,” says Dr Lewis.
“I’m very fortunate to be in Boston where my collaborators have developed a new sequence in MRI imaging, which is much faster. That is now becoming available to scanners throughout the world.
“We are refining and developing methods here which are also now available to scientists around the world to help our understanding of mental health and neurological conditions.
“The project also builds on fascinating research that has been done previously which has shown that sleep is related to mood disturbances, and the work from Rochester which showed how waste was cleared from the brain in sleeping rodents.
“I’m very excited about the project and hopefully the new information we discover.”
The project is being supported with grant funding through the Fellowship from 1907 Foundation, a charity that funds medical research for mental health and supports young scientists in their search for mental illness causes and cures.
“I applied to 1907 Foundation because they invited high risk new ideas,” says Dr Lewis.
“I’m very lucky to have had Federal funding for previous studies, but that is usually given for well developed projects.
“Here, I wanted to do something really new which gives the opportunity to explore a new phenomenon where we genuinely don’t know the outcome.
“1907 are very committed to advancing understanding and research in mental health and brain illness and wellness and I’m grateful to have their support with this study.”
Brady Smith, director of partnerships at 1907 Foundation, said: “Dr. Lewis’s research is the perfect example of what 1907 Foundation believes in; new science that will help us understand the biological causes of mental health issues.
“The answers are out there and we’re committed to working with like minded people in every industry to make real progress.”