BRUTE FORCE BRINGS BLUNT TRAUMA.
DANIEL EXAMINES THE BRAIN UNDER INJURY.

Call me crazy, but I'm obsessed with mixed martial arts (MMA). This admission comes, oddly enough, from a fledgling neuroscientist and part-time practitioner of Brazilian Jiu-jitsu and Muay Thai. There is something undoubtedly insane about MMA—from its combination of precision technique and strategy, to its simple objective: literally beating the piss out of one's opponent.

Combat sports have uniquely fascinating implications in terms of mental and neurological pathology. One clinical issue I’ve encountered in MMA is that of Chronic Traumatic Encephalopathy (CTE), which is called Dementia Pugilistica (DP) when referred to in the context of boxing. CTE is a somewhat mysterious condition that affects practitioners of contact sports: mostly boxers, professional wrestlers, hockey players and football players. Produced by repetitive concussive and subconcussive blows to the head, CTE produces a constellation of symptoms, particularly disorders of the frontal lobes.

CTE can produce a Parkinson's-like syndrome, complete with uncontrollable tremors and loss of coordination. Behaviorally, CTE/DP is associated with personality changes such as heightened aggression, memory loss, behavioral disinhibition and suicidal tendencies. The most obvious and noticeable symptom to the casual observer is an acquired stutter in speech, as well as a loss of ability to express oneself verbally. Postmortem studies have definitively confirmed the presence of the organic markers of CTE in a significant number of football and hockey players. DP has also been confirmed in scores of boxers, with its overall prevalence estimated at between 15-20% of all athletes with professional boxing experience. In MMA, however, the condition is all but unheard of, even controlling for the novelty of the sport. Given that MMA revolves around punches, kicks, elbows, knees and slams to the head, this lower incidence of damage is a source of much speculation.

The other aspect of fighting that so intrigues me is the psychology of controlled violence. In the cage, fighters seek to inflict maximal physical damage to their opponent. It seems to be sadistic. The question is then raised: How do these fighters reconcile the personalized application of violence (intrinsic to their avocation) with their outside-the-cage persona—which may be loving, compassionate, and not at all violent? Unfortunately, this question is largely outside the domain of questions that can be answered with empirical, neuroscientific techniques.

It is an area of inquiry, however, that I intend to pursue wherever my scientific career takes me.

Before I dive into the neuroscientific aspects of my interest in combat sports, I'd like to digress into a general history of MMA and the nature of my involvement with it. Until discovering MMA in 2007, I had no interest at all in the sporting world. Sure, I'd watch a football game every now and then, but I couldn't have given you any more information than who was playing in the annual Super Bowl. In the four short years since I started following MMA, I've gone far beyond the typical fan who follows main card fighters of the premiere MMA league, the Ultimate Fighting Championship (UFC).  I now check blogs obsessively, watch Strikeforce and follow the obscure and foreign leagues (M-1, Bellator, Titan, and DEEP).  I've also been training in the premiere striking and grappling aspects of the sport, Muay Thai and Brazilian Jiu-jitsu, for four to five days a week.

There are a number of elements that have converged to generate my addiction to MMA. On a visceral level, it gets my adrenaline pumping. While the safety record of the sport is excellent,  there is something primal and dangerous about MMA that I’ve never seen in any other competition. The sheer complexity of the sport is at first overwhelming. To the untrained eye, an MMA match looks first like a mindless, brutal dance of violence. Blows by elbows and knees are legal. Only tiny gloves are worn. Spurts of blood are possible—even likely. MMA can look like, as John McCain described it so famously, human cockfighting. Then, as a match progresses, the stand-up striking and clinch fighting give way to the ground phase (my personal favorite, which many a layman observes as so much dry humping). Truthfully, however, MMA is a game of kinetic chess. Unlike boxing, or even wrestling, the techniques used in MMA incorporate the entire body. It shows the full potential of the human corpus like no sport I've seen before. Each fighter (at least, the ones who expect to win) must bring a comprehensive strategy—tailored to the style of his or her new opponent—to the fight.

Early televised MMA matches were essentially an informercial for the ground grappling style of Brazilian Jiu-jitsu (BJJ). Boxers, kickboxers, Kung Fu and Karate stylists were flabbergasted to find, as they stepped into the cage, that their vaunted prowess was impotent against a stylist who had taken the time to consider how the other would fight. Royce Gracie, BJJ black belt and the first UFC champion, punctured the dreams of many wannabe ninjas and Kung Fu-ers by studying the striking aspect of practitioners of traditional martial arts. In absorbing early strikes and dragging an opponent to the ground—where complex mechanics of leverage and posture can overwhelm advantages in strength and athleticism—Gracie demonstrated the superiority of a fully thought-out, scientific approach to fighting.

Since the days of Royce Gracie, MMA strategy has evolved considerably. Japanese and American Greco-Roman wrestlers like Mark Coleman, Kazushi Sakuraba, Randy Couture and Dan Severn incorporated submission techniques and defenses into their arsenals, demonstrating how dominating ground control could yield ground-and-pound victory. Eventually, high-level strikers became wise to ground techniques and began incorporating defensive grappling techniques to keep fights standing where they had the advantage. Mirko Cro Cop and Chuck Liddell stood out as top fighters in the sport.

At the moment, high-level American collegiate wrestlers command most of the top-level ranks. Its focus on stifling position control, explosive movements and a wide range of effective takedowns makes wrestling training quite effective for MMA.

The grappling aspect of MMA to some extent accounts for the profoundly lower incidence of CTE in its ranks, as compared to similarly contact-oriented sports. Since fights can be won (occasionally) without a single strike to the face, and since positional control and submission can produce victory, MMA can in principle be an objectively safer sport than boxing or football. More commonly, however, MMA matches include seemingly dangerous features not seen in boxing or football. Knees thrown to the head (while the head is being held stationary in a clinch), or hammerfists to the head of a grounded opponent (first being struck, then bouncing off the unforgiving mat of an MMA cage)? These moves are more potentially injurious than a punch.

Concussions—the accumulation of which is known to produce CTE—occur when the brain accelerates inside the cranium and makes contact with the bony ridges in the front of the skull. When there is a “bounce” effect during the injury, a whiplash effect occurs that rocks the brain back-and-forth. This produces a greater likelihood of significant damage. MMA fights tend to be heavy in these strikes, particularly since the rise of dominating wrestlers, whose preferred strategy is to take their opponent down, battering their head with strikes and beating it against the canvas.

As early as the 1920s, it was suspected that there was a relationship between multiple concussive blows and the development of dementia in boxing. By the 1950s, researchers were calling for a ban on the sport (Corsellis, 1989). In the 1970s, researchers conducted controlled studies in which they became aware of evidence that concussive and subconcussive head injuries have a cumulative effect in terms of cognitive decline (Gronwoll and Wrightson, 1975). More recent research has indicated that survivors of multiple blunt force traumas to the head show heightened elevations of Tau proteins, a substance implicated in the “plaque” associated with Alzheimer’s (Hof, Bouras, Buee, Delacourte, Perl and Morrison, 1992). Unlike in Alzheimer's, however, this plaque accumulates not in deep brain tissue, but in the outermost areas most susceptible to trauma. The frequency, rather than the force of blows, seems to determine the extent of both Tau protein buildup, and cognitive decline.

How, then, can MMA fighters possibly be less prone to CTE/DP than boxers, who are subjected to only standing strikes, padded with 16-ounce gloves? The likely answer is somewhat paradoxical: Boxing gloves, contrary to popular perception, do not exist to protect anyone's head. They protect the hands of the puncher. The skull is made of significantly more extremely hard, dense bone than the hand.

A full-power punch to the head can easily break a person's hand. Hand breaks occur with some frequency in MMA. Off the top of my head, I can rattle off ten or more bouts in which a fighter broke their hand, courtesy of the relative lack of padding in the 4-ounce MMA gloves. Smaller gloves provide less protection to the hand, meaning that repetitive, full-power strikes to the head can be a costly strategy.

Thus, while the smaller gloves of MMA make for more agile hands and the ability to precisely aim knockout shots to the chin, the heavier gloves of boxing allow for more persistent hard shots to the head over the course of a single fight.

An additional factor that renders boxing more brain-injurious than MMA is the standing eight-count. While briefly a feature of some Japanese promotions in the early 1990s, the Unified Rules of MMA no longer allow for this practice; one that is a mainstay in boxing. A fighter is given eight seconds to recover from a knockdown blow—and, in principle, may continue fighting even after having been knocked out. The American Academy of Neurology indicates that for even a mild Grade 1 concussion (characterized by a transient disruption of consciousness), an athlete should wait at least 15 minutes before resuming strenuous activity, or else risk compounding the damage done by the concussion. Boxers given the eight count thus routinely suffer multiple Grade 1 (or worse) concussions over the course of a single evening, sometimes occurring within minutes of each other. This does occur in MMA, but is not systematically engrained in the rules. It is up to the referee's discretion to determine when a fighter is no longer intelligently defending him or herself, which does not necessitate the loss of consciousness in order to stop a fight. To my knowledge, the impact of temporally proximal concussion has never been explicitly studied using an experimental control group. This is something I would very much like to investigate.

It would appear, for the moment, that MMA is a safer sport than boxing (as well as football, hockey and pro-wrestling). That being said, MMA has only been a popular and visible sport for 20 years. Given time and more widespread participation, along with rule and strategy shifts, we may see a rise in CTE symptoms in MMA competitors.  I hope to make it part of my life's work to research the diagnosis and treatment of CTE/DP, as it is clearly correlated with a sport I love and presents fascinating, though tragic symptoms. I am excited to see the sport grow and flourish, and hope to engage with it on a research and treatment level, in addition to as a sportsman.


Notes:

Corsellis JA (1989). "Boxing and the Brain". BMJ 298: 105–109. 

T M McMillan, E E Glucksman,
"The neuropsychology of moderate head injury."
J Neurol Neurosurg Psychiatry. 1987 April; 50(4): 393–397.

Hof, Bouras, Buee, Delacourte,, Perl and Morrison, "Differential distribution on neurofibrillary tangles and sensile plaques in the cerebral cortex in postencephalitic parkinsonism." Neurosci Lett 139 (1992), 10-14.