Vulnerability of the Human Brain

"Instead of looking just at how the head is moving, we can visualize what's happening to a representative brain model inside the head."
"It's next-level information that can be used to validate the computer models used in helmet design."
"We're trying to understand the specific injuries that the cells undergo when the brain stretches. We want to know how the stretch and pull response of the brain might lead to injury and, specifically, where those injuries might be occurring." 
"We want to understand the critical limits of what those cells and those structures can take before they're affected."
"The brain is a very complex system and understanding exactly what leads to injury is not a trivial matter. We're still developing that understanding."
"The ultimate goal of this research is to change the way helmets are designed to improve helmet response, and also to influence in the longer term how helmets are evaluated and the safety standards applied to them."
Oren Petel, researcher, mechanical and aerospace engineering, Carleton University, Ottawa

Folds in a human brain. David Duprey / AP

"In hockey, you don’t see people dying from a hit to the head, and that is because the helmet works reasonably well for catastrophic injury."
“Football, you do get some deaths, but it’s fairly well-managed or mitigated. But neurological disease and concussion are not managed very well by a helmet. So this data will be very helpful for us; it will get us precision. The better data we get to capture the risk of concussion, the more innovation we can do in terms of helmets to reduce that risk."
“So, when we look at trauma related to neurological disease, we are only validating part of the brain and its response to trauma. This study is going to give us a really good opportunity to map different parts of the brain. . . . We are going to be able to get into parts of the brain we think are really important in terms of predicting risk."
"The brain is mostly water, so it doesn’t compress, but it does shear. It’s like jello. You can’t compress jello easily but you can shear it. And when you shear it, you damage it, and that is what is happening in the brain."
"We’re trying to understand trauma associated with sport that put athletes at risk for neurological disease. We connect the trauma to disease."
Dr. Blaine Hoshizaki, director, Neurotrauma Impact Science Laboratory, University of Ottawa

Although research into concussion has advanced in the last ten years more is required to understand what happens in the brain when a high-speed collision occurs. The design of a helmet to increase protection against injury is a high priority. Professor Petal aspires for the research he is engaged with to ultimately ensure greater safety for athletes in sports competitions such as hockey and football. From his position at Carleton University, Professor Petal applied for funding to develop a design he came up with, an X-ray system, and an impact research laboratory.

He found that funding with the Canada Foundation for Innovation and the Ontario Research Fund which came up with the required funding, and at a cost of about $320,000, both the lab and the X-ray system were completed in the space of two years. Ongoing research of Professor Petel's lab has brought contributions to his work from the Canadian Institutes of Health Research and the Natural Sciences and Engineering Research Council.

The completed laboratory is lined with lead to enable his very special type of research, equipped with a linear impactor, capable of delivering a head blow at 12 metres per second. An X-ray system capable of capturing images of the collision at 100,000 frames per second complete the major constituents of this very specialized research lab where Professor Petel and his research team are able to recreate what occurs with a helmet -- and the brain it protects -- during a high-speed collision.



The high-resolution images produced by the X-ray system lend themselves to the creation of a video -- known as cineradiography -- that illustrates interaction between a helmet and a head while at the same time revealing the physical response of the brain to an impact; the manner in which the brain compresses, twists and stretches. This revealing process and the information it contains will lead researchers in their work of designing improved helmets for hockey and football players, soldiers and cyclists.

In partnership with Defence Research and Development Canada, one project is to test what occurs to a synthetic brain within a plastic head model where markers are implanted inside the artificial brain for the purpose of measuring how it deforms in a collision. Yet another project in collaboration with Carleton neuroscience professor Matt Holahan is how pig brains [taken from an abattoir] respond to an impact. Validation of computer models commonly in use in head-injury research, another project.

When Dr. Petel studied at McGill University, he immersed himself in blast research when he joined the Shockwave Physics Group there. "It just sounded like a lot of fun, things impacting each other. And it was really challenging. Your experiments typically last several microseconds, several millionths of a second, and you have to collect all your data in the time before your experiment is destroyed", he explained.

He studied the response of ballistic armour and allied protective materials to an explosion, becoming ever more interested in the dynamics of blast injuries of what was occurring internally when a body was hit by a shock wave. And what made the lungs and brain so susceptible to injury, along with the question of how the tissue was becoming deformed. Which led the researcher to the conclusion that answers to those questions could improve protective equipment design.

As he initiated his study into injury biomechanics, at a conference years ago he questioned an experienced researcher why it was that more information relating to the reaction of internal tissue to a blast wasn't available. The response was there was no known way to measure what was happening at such high speeds. "So why isn't someone developing something to measure this?", he asked. "If you think you're so smart, why don't you do it?" was the comeback. So he set about to do just that.

Here, he sets up a machine that hits the “head” with great velocity from which he can measure impact and damage to the head. Julie Oliver / Postmedia

Concussion Awareness in Children

"In our study girls across age groups were more symptomatic [of concussion] than boys, and adolescent girls' symptoms change was slower than that of adolescent boys."
CHEO Research Institute/University of Ottawa study

"It's important to start figuring out what's causing these differences between male and female adolescents, because this is really significant."
"[Researchers] need to tease out exactly what's going on [to enable improved concussion treatment for young patients]."
"When you look at a pediatric brain, the brain of an 18-year-old is very different from the brain of a five-year-old. So the question is: Are the recovery patterns going to be the same?"
"Are they the same between males and females?"
Dr. Andree-Anne Ledoux, Research Associate, Children's Hospital of Eastern Ontario

uOttawa  New Research Shows Symptom Improvement after Concussion in Children Varies Across Age Groups and Sex

According to senior scientist at the CHEO Research Institute, and co-author of the study Dr. Roger Zemek, the findings give doctors a track to guide them in understanding whether a child's recovery from concussion is within expected ranges. One other finding out of the study was its acknowledgement that the rate of reported head injuries in North America during the past decade has increased two to fourfold. Making it even more important for treating physicians to try to fully understand all the variables of recovery from concussion.

This discussion resulted from a large, national study taken on by CHEO Research Institute and the University of Ottawa investigators. They concluded from the evidence they studied that over half of adolescent girls (aged 13 to 18) experience post-concussion symptoms following 12 weeks after the initial injury. Over half of all adolescent boys after four weeks following a concussion were free of symptoms, by contrast.

The study, published recently in the medical journal JAMA Pediatrics found as well that age was a factor in concussion recovery, that symptoms had a tendency to last for a longer period in adolescents than they did in younger children. As the latest published research on the matter, it adds to a growing body of evidence suggesting girls are more vulnerable to concussions and slower to recover from them.

Data from 2,716 children and adolescents diagnosed with concussions at nine pediatric hospitals across Canada was examined by the researchers. Individuals were followed through the research period for up to a year, with patients reporting their symptoms based on a standardized questionnaire. Both the rate of change in symptoms and the point where patients claimed to be fully recovered were tracked. Across all age groups, the first week of recovery was the most critical, according to the study, with many symptoms resolving themselves within the first seven days post-concussion. 

In the youngest patient cohort (ages five to seven) individuals being tracked reported most improvement in the first week. Within that group, 63.8 percent noted their concussion symptoms had abated. Headaches, nausea. anxiety, depression, sleep disturbances, memory or concentration issues and sensitivity to light or noises ranked among the symptoms identified.

In the older age group representing preteens (ages eight to 12) and adolescents (ages 13 to 18), symptoms had a tendency to improve markedly over the first two weeks, then for another two weeks, to plateau. Irrespective of their ages or sex, at least half of all patients fully recovered following four weeks post-concussion. Adolescent girls represented the sole exception as their recovery tended to be substantially protracted, most not free of symptoms a full three months following injury.

The reason for the differences between adolescent males and females in their recovery remains elusive to scientists. Dr. Ledoux hypothesized that testosterone may offer the brain protection of a kind, or that the hormones that puberty releases makes female more vulnerable to the concussion's effects. Other scientists are known to have theorized that adolescent girls are more likely to report their concussion-related symptoms than their male counterparts.

Concussion symptoms

Cognitive (thinking):

• Difficulty concentrating and paying attention
• Trouble with learning and memory
• Problems finding words and putting thoughts into words
• Easily confused and losing track of time and place
• Slower thinking, acting, reading and speaking
• Easily distracted
• Trouble doing more than one thing at a time
• Lack of organization in everyday tasks

Physical:

• Headache, neck pain
• Nausea
• Lack of energy
• Dizziness, light-headedness, loss of balance
• Blurred or double vision and sensitivity to light
• Increased sensitivity to sounds
• Ringing in the ears
• Loss of sense of taste and smell
• Change in sleep patterns, especially waking up at night

Social and emotional:

• Mood changes: irritability, anxiety, depression
• Less motivation
• Easily frustrated, overwhelmed, tearful
• More impulsive and lacking normal inhibitions
• Withdrawn, wanting to avoid social situations with lots of people
• See your family doctor if your child or teen is having trouble coping with moods and emotions. If things don’t improve, you may need to consult a mental health specialist.

“Why Professional Football Players Chose Not to Reveal Their Concussion Symptoms during a Practice or Game”

"What can be difficult to rationalize is that this type of behaviour is occurring at a time when athletes have never been better educated about concussions."
"This is not a problem isolated to CFL (Canadian Football League) players, as we have seen identical behaviour in male and female university athletes."
"What we have to figure out now is how we get athletes to change their behaviour when routine concussion education may not be enough."
Dr. Scott Delaney, assistant professor, researcher, McGill University

"Oh, there's definitely a lot more awareness. We have a guy watching from the press box now, and if they think there's a player who needs to be pulled from the game, he has no choice."
"It happened to a guy on our team. He caught a ball and fell on his head. He was OK, but he just sat there, didn't want to jump up too fast, and the spotter pulled him and made him go through the protocol."
"He was fine and came back later in the game, but they checked him out."
Ernest Jackson, wide receiver, Ottawa Redblacks, Montreal Alouettes

Ottawa Redblacks wide receiver Ernest Jackson (9) catches a touchdown pass during overtime CFL Grey Cup action Sunday, November 27, 2016 in Toronto. Nathan Denette / THE CANADIAN PRESS

A study conducted by a team of researchers from the McGill University Health Centre seems to conclude that though those involved in professional sport are now aware of the dangers inherent in concussions, particularly in sports where repeat concussions were always accepted as part of the game, now equating with long-term, extremely dangerous health effects, the players themselves tend to minimize the dangers they face, reluctant to take precautionary measures after a concussion to ensure they heal well before continuing to play.

The study resulted from a 2016 survey where players voluntarily reported on their experiences from the 2015 season. Published in January 2018's Clinical Journey of Sports Medicine, roughly one quarter (23.4 percent) of the 454 players responding to the survey reported having suffered at least one concussion during practise or a game, while 82 percent of that one quarter kept silent about the concussion rather than reporting it to a coach or training staff member. Moreover a mere 6 percent of players who had claimed they intended to seek medical treatment post-game, did.

Dr. Delaney, team physician for the CFL's Montreal Alouettes, led the study whose results present as no big surprise in recognition of the competitive nature of the athletic community and their traditional reaction to injuries, seeing them as an impediment to continue playing the entire game, and thus minimizing injury to themselves, keeping it from those who might insist they sit out the rest of the game and seek medical help. It is largely the players themselves for whom head trauma is a matter to be kept to themselves.

Now, however, that the sport industry itself has recognized the reluctance of players to reveal their injuries, independent concussion spotters have been deployed to identify those instances where players appear to have suffered serious injury, so they could intervene and remove them from the game. Dr. Delaney distributed 100 questionnaires to each of the nine head trainers and therapists in the CFL to distribute to players at the 2016 training camps. In total 662 players had taken part in at least one game.

And of that 662 number, there were 454 voluntary respondents, casting their minds back over the 2015 season of play to recall incidents of injury and how they had reacted to them. Of the respondents, 106 felt reason to believe that had suffered a concussion, while 87 of that number admitted they hadn't sought out medical attention; the most common reason cited (from 49 of the 106) being they failed to identify the concussion as serious, feeling that no further harm would result when they continued to play after sustaining the injury.

Other reasons fell into place when 42 players revealed they hadn't wanted to be removed from a specific game, and 41 claimed to have been concerned with the prospect of missing future games should they admit to having suffered a concussion. Dr. Delaney concluded that awareness of concussion symptoms and the follow-up medical protocol often fails to translate to "safe and appropriate behaviour at the time of the injury".

He speculated, along with the other researchers in discussion whether the perception among players of the seriousness of the issue might be brought home more effectively, causing players to react differently should the word 'concussion' be replaced with the term 'brain injury'. Brain injury necessarily conjures up deep-seated fears of possible lethal end-results, while the word concussion seems far less urgent, given the fact that so many children, let alone adults, at some time in their lives do suffer a concussion.