Predicting recovery after brain injury

Dr. Loretta Norton, Assistant Professor of Psychology and one of the first researchers in the world to measure brain activity in the ICU, led an interdisciplinary team of researchers, including neurologists at London Health Sciences Centre and Lawson Health Research Institute, to tackle the question of which intensive care unit (ICU) patients will survive severe brain injuries.

“We know that predicting meaningful functional recovery after an acute severe brain injury is a substantial clinical challenge in the ICU,” explains Dr. Norton. “It is an important endeavour because meaningful conversations surrounding the continuation or withdrawal of life-sustaining therapies occur.”

Currently, clinical tools exist to predict poor outcomes following injury from traumatic brain injury and cardiac arrest. Still, there is a lack of reliable clinical tools to predict a good recovery. In the absence of those negative findings, an individual is thought to have an indeterminate outcome.

“Simply put, we just don’t know how well an individual will do following their injury,” says Dr. Norton. “I hope my research will have a meaningful impact on those families and healthcare professionals tasked with making such difficult life and death decisions.”

Dr. Norton’s research uses functional MRI (termed fMRI) to determine brain function in patients. “I try to determine if patients can hear, perceive speech, understand language, or even follow our commands by examining their brain activity,” she explains. “Sometimes it comforts families to know that many patients still retain the ability to hear sounds and speech.”

Her team measured brain activity in 25 patients at one of London’s two ICUs in the fi rst few days after a serious brain injury and tested whether it could predict who would survive and who would not. Combining fMRI with an AI application known as machine learning, the team looked at certain brain networks that are thought to be active even when your brain is at rest. They found they could predict patients who would recover with an accuracy of 80 per cent, which is higher than the current standard of care.

Although it is an exciting discovery and a step in the right direction for more accurately predicting recovery, more data is needed to create a better prediction tool. Dr. Norton and her team are continuing to collect datasets. They are also moving much of their research to bedside tools, such as functional near-infrared spectroscopy (fNIRS), so patients don’t have to be transported to the MRI suite for imaging. They can also extend their work with fMRI to patients who can’t otherwise communicate, such as two patients Dr. Norton studied with Guillain-Barre Syndrome.

Currently, Dr. Norton’s research team in the ICU and hospital setting includes two King’s psychology alumni. Sophie Kelly '21 is a second-year master’s student in Neuroscience at Western University. She is researching sex differences in the neurocognitive recovery of patients after cardiac arrest. Hassan Al-Hayawi '22 is also a second-year master’s student at Western University. He uses high-density EEG to understand cognitive processing in critically ill patients.