Brain Concussion: How Easily Does It Occur?

As an increasing number of professional athletes are choosing early retirement over continued risk for head injury, the subject of concussions is heating up again. In recent years traumatic damage has been discovered during the autopsies of former football players, but NFL players aren’t the only ones who feel alarmed; active and competitive individuals of all ages are equally concerned.

With so much attention focused on head injuries, most lay people understand the concept of a concussion and the types of situations which generally cause it. What they may not know is exactly how much bumping around it takes to damage the brain. We tend to imagine the brain as being in a fixed position within the skull, when in fact it floats in cerebrospinal fluid. This protective design allows the brain to move, but that movement becomes a liability when concussion occurs.

The Center for Disease Control and Prevention (CDC) describes a concussion as being “… caused by a bump, blow, or jolt to the head or by a hit to the body that causes the head and brain to move rapidly back and forth. This sudden movement can cause the brain to bounce around or twist in the skull, creating chemical changes in the brain and sometimes stretching and damaging brain cells.”

Brain Concussion
Brain Concussion

Experts call the injuries from that back and forth movement coup and countercoup. When the brain suffers an initial (primary) impact to one side within the skull, this is known as a coup injury. When the brain then bounces back to the other side, this is known as a secondary contrecoup injury. The result is damage to two sections in the brain, which can cause the stretching and twisting of the cells in the brain.

How much force is required to cause those injuries? According to an article from the University of North Carolina at Chapel Hill, researchers estimate that any hit that occurs above 85g would likely cause a concussion. “In a roller coaster or fighter jet, a person withstands about 4.5g. In a car crash at 25 miles per hour, a test dummy hits the windshield at 100g. In football the majority of impacts fall between 20g and 25g. But hits of 50g to 120g are common, and some approach 200g.”

Given those calculations, concussions likely occur more often than most people realize, many times resulting in brain injury that alters quality of life. What might that look like? Concussion Symptoms can range from headaches, problems with memory, mood and appetite changes to difficulty with work and school. The impacts of concussion continue long after the injury occurs, and those who experience concussion often need ongoing medical help. Many will need the expertise of the legal community as well. With wrap-around support, clients can access the services they need to cope with their injuries.

VIDEO: The Unfixed Brain. (University of Utah Neuroscience Initiative)


In this teaching video, Suzanne Stensaas, Ph.D., Professor of Neurobiology and Anatomy at the University of Utah School of Medicine, demonstrates the properties and anatomy of an unfixed brain. WARNING: The video contains graphic images, a human brain from a recent autopsy. Background noise is unrelated to this brain or the deceased.

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