Can Bumps to the Head Change Behavior?

Repeated brain trauma changed behavior and thinking of athletes in study

/ Author:  / Reviewed by: Chris Galloway, M.D. Beth Bolt, RPh

(RxWiki News) Athletes in contact sports generally wear protective gear and take various other safety precautions. Even so, injuries do occur, including ones that can lead to brain damage.

Multiple concussions and other brain injuries have been associated with brain disease.

A new study suggests that one of those diseases, chronic traumatic encephalopathy, may significantly and negatively affect the behavior, mood, memory and thinking ability of former athletes who develop it.

"Protect yourself from repeated brain injury."

Robert A. Stern, PhD, a neurology and neurosurgery professor at Boston University School of Medicine, was this study's main author.

Dr. Stern and his team of researchers examined the brain health of 36 amateur and professional athletes who had died and whose cases were on file with the Boston University Center for the Study of Traumatic Encephalopathy brain bank.

Football players accounted for 29 of the study subjects; 22 of them had played professionally. Four were college football players, and three played only high school football. The other study subjects included professional and amateur wrestlers, boxers and hockey players.

The researchers reviewed the athletes' medical records and examined their brain tissue. They also interviewed relatives of 23 of the 36 athletes.

Based on their findings, the researchers concluded that behavioral and mood problems were the first signs of chronic traumatic encephalopathy (CTE) in 22 of those athletes. For 11 of them, memory and thinking problems were their first symptoms of CTE. Three athletes had displayed no symptoms of CTE before they died.

CTE is diagnosed after a person has passed away and the brain can be examined. In addition to athletes, CTE also has been reported in military personnel exposed repeatedly to explosions and in others with repeated brain injury.

Among the 36 former athletes, those who showed signs of mood changes were more "...explosive, out of control, physically and verbally violent and depressed" than those whose CTE symptoms mainly involved declining memory and thinking skills, the researchers wrote.

The athletes' family members reported that 73 percent of those with altered moods and behavior were “explosive,” while 27 percent of those with memory and thinking problems were described as explosive, the researchers wrote.

"Out of control" was how family members described 64 percent of the athletes with mood and behavioral symptoms and 27 percent of the athletes with declining memory and thinking skills.

Also, 68 percent of those with mood and behavior problems were described as physically violent, while 18 percent of those with memory and thinking difficulty were described that way.

A total of 74 percent of those with mood and behavior problems and 18 percent of those with memory and thinking challenges were verbally abusive.

Depression was experienced by 86 percent of those in the behavioral group and 18 percent of those in the group with memory and thinking difficulty. Sadness, hopelessness, suicidal thoughts and paranoia were other problems that the researchers found in the study subjects.

According to these researchers, those with behavior and mood problems began to show symptoms of those problems by an average age of 35. On average, those with memory and thinking problems began to show symptoms when they were 59.

On average, the study subjects died when they were about 57 years old.

The researchers said it was worth noting that the size of their studied population was small. That fact makes it "...unclear whether these two [groups with CTE] are representative of all individuals with CTE," the researchers wrote. "Further research is needed to clarify and validate these findings."

The researchers also noted that they did not compare athletes with CTE to those who did not have CTE, a comparison that also would help prove the validity or invalidity of their findings.

These researchers also wrote that additional research is needed to determine the validity of another part of their findings: ten of the CTE study subjects also had been  diagnosed with dementia, a decline in brain functions that affect mental skills. Four of them were diagnosed with Alzheimer's disease, a form of dementia that gets worse as time passes.

In addition, four of the subjects were diagnosed with dementia pugilistica, also known as football-related dementia, the researchers wrote. Football-related dementia may affect a person's ability to walk and other physical abilities, in addition to their mental skills.

On average, those with dementia were diagnosed when they are almost 73 years old. Their symptoms of dementia were first seen when they were almost 58 years old.

In addition to athletes, military personnel and others suffering repeated head injuries have developed CTE.

“With the increased interest in head injuries and their long-term effects in athletes, this study adds more interesting data to the knowledge that we currently have. While we still cannot diagnose this condition in living patients, studies like this allow us to gather information that may help us identify people with this type of damage earlier and perhaps develop therapies that may be helpful during the person's life," Dr. Kenneth Podell, co-director of the Houston Methodist Concussion Center in Houston, Texas, told dailyRx News.

"Although more research is needed, we can also apply the new findings to help researchers, coaches, parents, equipment manufacturers, sport organizations and others to better protect athletes - both young and old - so that we can try to decrease the risk of developing CTE and ultimately prevent it from developing in the first place," said Dr. Podell. 

“It is a very important study. Contact sports are so common in this country and repeated contact injuries can lead to both behavioral disorders and serious cognitive difficulty," Shanker Dixit, MD, medical director of the Neurology Center of Las Vegas, NV, told dailyRx.

Two of Dr. Dixit's own patients are former boxers, including one who developed Parkinson's disease. Parkinson's is a brain disorder that causes a person to tremble, have difficulty walking and talking, among other problems.

Dr. Dixit has helped led efforts to safeguard boxer's health, requiring them to undergo a brain exam before they are allowed into the boxing ring. "That's a good thing," Dr. Dixit said.

Especially in a sports-oriented culture, he added, "We have to be very careful. For people who are risk for impact concussions, we must monitor their neurological status."

The study was published online August 21 in Neurology.

The National Institutes of Health, US Department of Veterans Affairs, National Operating Committee on Standards for Athletic Equipment, Sports Legacy Institute, National Football League and Andlinger Foundation funded the study.

Its authors included individuals who have been paid consultants to pharmaceutical companies, the NFL and other government agencies and private health organizations.

Review Date: 
August 19, 2013
Last Updated:
August 28, 2013