A team led by Western neuroscientist Jörn Diedrichsen has received $1 million in funding from the Once Upon a Time Foundation to develop a growth chart for the human cerebellum across an entire lifespan from birth to 80 years.
The cerebellum is the part of the brain that was historically thought to be primarily responsible for motor control and balance. New research has revealed that it supports cognitive and social functions as well, and cerebellar dysfunction has been linked to conditions such as autism, dyslexia and schizophrenia. The growth chart will allow clinicians for the first time to track neural development across a lifespan, providing a framework for diagnosis and prognosis.
Over the next three years, Diedrichsen and his collaborators will create an analytics pipeline that will estimate the volume of different parts of the cerebellum from individual MRI scans, include those from full-term and pre-term infants, and provide age-dependent norms of what constitutes normal development.
This pipeline will allow clinicians around the world to estimate the influence of specific clinical risk factors informed by a large population of children who developed neurologically in expected ways. In children born prematurely, clinicians can use the growth map to also be able to predict anatomical and behavioural development in motor, social, language and executive domains.
Jörn Diedrichsen
"If you go to the pediatrician, they might tell you that your child is in the 20th percentile for body weight. That is not alarming, but it can be a warning sign if a year ago the child was in the 70th percentile," said Diedrichsen, the Western Research Chair for Motor Control and Computational Neuroscience. "As such, growth charts have been a cornerstone in pediatric medicine since the 1950s. Surprisingly, however, growth charts for the human brain are not currently in common practice."
There has been a lot of excitement in the last four to five years about developing growth charts for the human brain, says Diedrichsen, but these efforts do not cover the cerebellum, or if they do, do not cover it with precision despite the fact medical imaging has been commonplace for decades. The cerebellum is not just involved in motor control, it has many different functions, which makes it important to develop growth charts in high resolution. One technical advancement the team will deliver is to introduce growth charts that quantify the development of different, functionally defined subregions of the cerebellum. For example, it will allow clinical researchers to identify exactly the parts of the cerebellum where lesions or impaired development increase the risk of developing autism.
"Luckily, we can rely on mostly established algorithms and use the large open data sets available," said Diedrichsen, a computer science professor. "We will be able to integrate data from an estimated 70,000 brain scans from people between the ages of 0 and 80 years."
The Raynor Cerebellum Project, part of the Once Upon a Time Foundation, aims to improve the lives of individuals with disorders like cerebellar degeneration, cerebellar hypoplasia or Joubert syndrome in the next seven to 10 years, through new research initiatives like the Diedrichsen-led "growth chart" and the fostering of a research culture of collaboration between labs at multiple institutions across multiple disciplines.
"This project is not the standard scientific project that ends in a few peer-reviewed publications," said Diedrichsen. "Instead, our measure of success is how many researchers in the community will use our system, how well it serves the clinical community, and whether we will be successful in an ultimate clinical translation."
Diedrichsen, a faculty member in the Western Institute for Neuroscience, says it is not easy to get funding for this type of project, which makes the Raynor Cerebellum Project so unique.
"We are approaching this project with a different mindset - it is as much a software engineering challenge to build a system that can run stably across different data sets and in different hospitals, as it is a scientific challenge. The support of the Raynor Cerebellar Project will really accelerate science in this area," said Diedrichsen.
For the growth chart, Diedrichsen has partnered with collaborators at Western and beyond, including Ryan Muetzel at Erasmus MC (Netherlands), Andre Marquand at Radboud University (Netherlands), Steven Miller at The University of British Columbia, Jessie Guo at Sick Kids, Carlos Hernandez-Castillo at Dalhousie University and Mallar Chakravarty at McGill University.
