Football and hockey don’t necessarily doom players’ brains to serious damage | Science News for Students

Football and hockey don’t necessarily doom players’ brains to serious damage

Tests of former pro athletes showed their brains appear better than even the players had expected
Sep 11, 2018 — 6:45 am EST
a computer generated image of a football player tackling another football player holding the football

Football tackles can leave players sore — and sometimes suffering a concussion. But new data from professional athletes suggest that not all players sustain serious long-term brain damage from years of play.


A career of hard knocks to the head will not necessarily leave pro athletes with serious, permanent brain damage. That’s the take-home message from a small study. It included pro athletes who had taken a lot of hard hits during their career — including to the head. The findings now challenge what had been suggested by other studies that had autopsied the brains of former college and pro football players.

The new data come from tests of 21 retired athletes. All had been football players with New York’s Buffalo Bills or hockey players with the Buffalo Sabres.

Each player allowed researchers to extensively scan his brain. The players also took behavioral tests. From these, the scientists turned up no signs of early dementia or unusual rates of mental decline. Both can point to a brain disease known as CTE. That’s short for chronic traumatic encephalopathy (KRON-ik Traw-MAA-tik En-seff-uh-LAH-puh-thee). Today, doctors diagnose CTE only by looking at a brain after someone has died.

For the new study, University of Buffalo researchers gave the athletes a battery of clinical tests. These measured brain function and mental health. Other tests probed such health features as diet, obesity and history of drug or alcohol use. Findings from these men were then compared to those from 21 noncontact athletes (such as runners and cyclists). 

The former hockey and football players had expected bad news. They “were pretty much their own worst critics,” says Barry Willer, an author of the new research. This psychiatrist studies traumatic brain injury at the University of Buffalo in New York. The athletes had believed their brains to be impaired, he notes.

In fact, the new tests did not find high rates of problems with memory, solving problems, decision making or being able to plan things. The researchers also found no evidence of declines in the men’s attention, language and spatial abilities. Based on these tests, none of the former football and hockey players appeared to have early-onset dementia.

The good news “was a big surprise to us — and a big surprise to the athletes,” Willer says. The results are in line with several earlier studies of living athletes. This includes one published last year. It, too, found no major problems in the mental abilities of 33 retired hockey pros.

The authors shared their latest findings in a series of papers. All were published August 7 in the Journal of Head Trauma Rehabilitation.

Not all athletes were totally fine

Eight of the 21 contact athletes appeared to show mild mental impairment. So did three of the 21 other athletes. Such mental problems could hint that dementia will develop. But the difference in rates between the two groups may not be due solely to more head knocks in the hockey and football players. Education, IQ and a man’s weight also could have contributed to some of the apparent difference. As such, the authors say they cannot firmly link rates of mild mental decline seen to which sport a man had played.

Brain scans told a similar story. Several types of magnetic-resonance imaging, or MRI, turned up no big differences. They showed no big differences in brain anatomy. They also didn’t show big links to behaviors in athletes with a history of contact versus noncontact sports. Still, seven of the non-contact athletes showed microbleeds. Scientists have linked these tiny ruptures in brain blood vessels with poorer brain function. The same microbleeds showed up in only two of football and hockey players.

Carrie Esopenko works at Rutgers University in Newark, N.J. She’s trained as a cognitive neuroscientist and a psychologist. Studies of the living, as here, “are exactly what we really need,” she says. Such studies “are really going to help us understand what’s going on in these lives.”

The new study also may ease some recent concerns. Last year, researchers had reported in JAMA that 110 of 111 autopsies turned up CTE in the brains of former pro football players. Those brains had been donated by family members who had suspected something was amiss. However, such concerns and symptoms may mean this sample represented the sickest of former players.

Indeed, notes neurologist Rodolfo Savica: “People who do not have symptoms do not donate their brains.” Savica works at the Mayo Clinic in Rochester, Minn., and was not involved in either study.

Athletes who took part in the new study were in their mid-50s. So they would have been relatively young for a dementia diagnosis. Still, based on earlier reports of brain damage, the researchers had expected to find some signs of dementia in these football and hockey players.  

To better understand the prevalence of CTE, though, more research will be needed. Researchers want to see a larger sample of athletes who suffer blows to the head as well as those who don’t. “There’s a lot more that we don’t know than we do know,” says coauthor John Leddy of the University of Buffalo’s Concussion Management Clinic.

Power Words

(more about Power Words)

anatomy     (adj. anatomical) The study of the organs and tissues of animals. Or the characterization of the body or parts of the body on the basis of its structure and tissues. Scientists who work in this field are known as anatomists.

behavior     The way something, often a person or other organism, acts towards others, or conducts itself.

blood vessel     A tubular structure that carries blood through the tissues and organs.

brain scan     A technique to view structures inside the brain, typically with X-rays or a magnetic resonance imaging (or MRI) machine. With MRI technology — especially the type known as functional MRI (or fMRI) — the activity of different brain regions can be viewed during an event, such as viewing pictures, computing sums or listening to music.

chronic traumatic encephalopathy     Also known as CTE, it's a term for long-lasting brain disease brought on by head injuries (often sustained in sports or military service). This disease often is progressive, meaning it worsens with time.

clinical     (in medicine) A term that refers to diagnoses, treatments or experiments involving people.

coauthor     One of a group (two or more people) who together had prepared a written work, such as a book, report or research paper. Not all coauthors may have contributed equally.

cognitive     A term that relates to mental activities, such as thinking, learning, remembering and solving puzzles.

concussion     Temporary unconsciousness, or headache, dizziness or forgetfulness due to a severe blow to the head.

dementia     A type of mental disorder caused by disease or injury that causes people to gradually lose all or part of their memory. It may start out temporary and build to a permanent condition where the ability to reason also is impaired.

develop     To emerge or come into being, either naturally or through human intervention, such as by manufacturing. (in biology) To grow as an organism from conception through adulthood, often undergoing changes in chemistry, size and sometimes even shape.

diagnose     To analyze clues or symptoms in the search for their cause. The conclusion usually results in a diagnosis — identification of the causal problem or disease.

diet     The foods and liquids ingested by an animal to provide the nutrition it needs to grow and maintain health.

encephalopathy     A term for any type of disease that alters the structure of the brain or how well it functions.

function     A relationship between two or more variables in which one variable (the dependent one) is exactly determined by the value of the other variables.

IQ     Short for intelligence quotient. It’s a number representing a person’s reasoning ability. It’s determined by dividing a person’s score on a special test by his or her age, then multiplying by 100.

link     A connection between two people or things.

mental health     A term for someone’s emotional, psychological and social well-being. It refers to how people behave on their own and how they interact with others. It includes how people make choices, handle stress and manage fear or anxiety. Poor mental health can be triggered by disease or merely reflect a short-term response to life’s challenges. It can occur in people of any age, from babies to the elderly.

magnetic resonance imaging     Also known as MRI. It’s an imaging technique to visualize soft, internal organs, like the brain, muscles, heart and cancerous tumors. MRI uses strong magnetic fields to record the activity of individual atoms.

neurology     A research field that studies the anatomy and function of the brain and nerves. People who work in this field are known as neurologists (if they are medical doctors) or neuroscientists if they are researchers with a PhD.

neuroscientist     Someone who studies the structure or function of the brain and other parts of the nervous system.

obesity     (adj. obese) Extreme overweight. Obesity is associated with a wide range of health problems, including type 2 diabetes and high blood pressure.

psychiatrist     A medical doctor who spends many years learning to study and treat diseases of the human mind. Treatments may consist of talking therapies, prescription drugs or both. This medical field is known as psychiatry.

psychologist     A scientist or mental-health professional who studies the human mind, especially in relation to actions and behaviors. 

rehabilitation     The act of restoring something to its original state. Often called “rehab” for short, the term is used commonly for both physical injuries (such as regaining muscle strength after an accident, for example) and mental problems (such as addiction to drugs, alcohol or other substances).

spatial     An adjective for things having to do with the space where something is located or the relationships in space between two or more objects.

symptom     A physical or mental indicator generally regarded to be characteristic of a disease. Sometimes a single symptom — especially a general one, such as fever or pain — can be a sign of any of many different types of injury or disease.

trauma     (in medicine) An injury, often a fairly severe one. This term also can refer to a severely disturbing incident (such as witnessing a battlefield death) or memory.

traumatic brain injury     Damage to the brain that results from an external shock, such as an explosion, or a direct impact (as can occur in a car accident). Also called TBI, the damage can lead to either temporary or permanent impairment of thinking, memory and movements of the body.


Journal: B. Willer et al. A preliminary study of early-onset dementia of former professional football and hockey players. Journal of Head Trauma Rehabilitation. Published online August 7, 2018. doi: 10.1097/HTR.0000000000000421.

Journal: B. Willer et al. Evaluation of executive function and mental health in retired contact sports athletes. Journal of Head Trauma Rehabilitation. Published online August 7, 2018. doi: 10.1097/HTR.0000000000000423 .

Journal: R. Zivadinov et al. Multimodal imaging of retired professional contact sports athletes does not provide evidence of structural and functional brain damage. Journal of Head Trauma Rehabilitation. Published online August 7, 2018. doi: 10.1097/HTR.0000000000000422 .

Journal: J. Baker et al. An exploratory study of mild cognitive impairment of retired professional contact sport athletes. Journal of Head Trauma Rehabilitation. Published online August 7, 2018. doi: 10.1097/HTR.0000000000000420.