Does Second Impact Syndrome Exist?

It has often been reported that when a person suffers a second concussion (mild traumatic brain injury) before recovery from the first concussion takes place, that catastrophic brain swelling and death can result. This has been alleged to occur based on anecdotal information and when it happens (usually in young male athletes) it is referred to as “second impact syndrome” (SIS). SIS is often reported as a factual entity in the media and in the medical literature.


However, when one assess the evidence-based data for whether SIS truly exists, we are left with far more questions than answers. As Dr. Paul McCrory and colleagues (2012) put it, “The phenomenon of the second impact syndrome (SIS) continues to appear in the medical literature in spite of the lack of systemic evidence for its existence.” While McCrory's work is accessible through medical libraries, I have never seen in discussed in mainstream media coverage of SIS. Thus, a brief summary is presented below for ease of access for those who are interested.

Dr. McCrory has been studying SIS with evidence-based methods for over a decade. In fact, the seminal empirical study on this topic was performed by McCrory and Berkovic (1998). This was followed by a classic 2001 paper by McCrory entitled “Does Second Impact Syndrome Exist?,” which is the basis of the title of this blog entry.

In the 2001 paper, McCrory noted that 35 cases from the National Center for Catastrophic Sport Injury (NCCSI)  were cited as probable cases of SIS but not published in scientific journals due to lack of confirmatory details. McCrory referenced his 1998 study, in which he and Berkovic independently applied four basic criteria to 17 published SIS cases to determine how many would result in a diagnosis of definite SIS. Those criteria were as follows:

1) Medical review after a witnessed first impact.

2) Documentation of ongoing symptoms following the first impact up to the time of the second impact.

3) Witnessed second head impact with a subsequent rapid cerebral (brain) deterioration.

4) Neuropathological or neuroimaging evidence of cerebral swelling without significant intracranial hematoma (bleeding) or other cause for edema (swelling).

Not a single patient met all four criteria. Thus, there was not a single confirmed case of definite SIS in any of the cases reviewed despite the fact that all of them had been previously described or quoted as examples of SIS. Further analysis of the study revealed even more interesting details. For example, in 11 of 17 published cases, there was no evidence that a second impact actually occurred despite the fact that four of those cases had been heralded as “classic” examples of SIS in the literature. They also found that most of the evidence used to support a first impact was based on teammate recall (subjective evidence) rather than video tape (objective evidence).

Rather than merely accepting that the teammate recall was correct, McCrory and Berkovic performed a study of 102 football players to assess the reliability of their recall for concussive injuries sustained by their teammates. Their recall was compared to video-taped reviews and recall of the injured player. McCrory and Berkovic found that the teammates significantly over-reported the presence of initial impacts. In other words, they tended to report that a concussion occurred when objective evidence indicated otherwise. In only 11% of cases was there immediate medical documentation after the reported initial impact. Seventy-one percent of the cases were described as not meeting SIS criteria, whereas five of the 17 cases (29%) met three of the four criteria, with neither having a medical review after a witnessed first impact. These cases were described as probable (but not definite) SIS.

In McCrory’s 2001 article, he questioned why it is that SIS only tends to be reported in the United States despite the fact that similar or greater concussion rates occur in competitive sports throughout the world. To research this issue further, McCrory (who is from Australia) analyzed all deaths due to Australian football from 1968-1999. In these 32, there were 25 player deaths. Of these, nine were due to a neurological trauma and the others were due to non-neurological factors. Of the nine traumatic brain injury deaths, how many met criteria for SIS? None. No cases of SIS despite the fact that McCrory notes that the concussion risk in Australian football is about eight times that of American football. The risk of death from brain injury in this sample was 1 in 30 million player games. McCrory also questioned why there are not more cases of SIS in boxing compared to other sports due to the frequent concussive head trauma experienced in most fights.

McCrory also stated in his 2001 paper was that the published 1984 case by Saunders and Harbaugh that first used the term “second impact” to describe the death of a 19-year-old college football player actually did not have a described second impact. It is true that the wording used by Sanders and Harbuagh did not describe the second impact but it is also true that their wording does not preclude that some type of second impact to the head occurred. Specifically, all that they say about the second impact is as follows, “Despite accounts of no unusual head trauma, he walked from the field and collapsed.” The key word is “unusual.” This technically does not mean that no head trauma occurred but it means that there was no head trauma that anyone observed that was out of the ordinary. One could argue, however, that a head injury significant enough to cause a concussion would be considered unusual.
  
McCrory noted that belief in SIS has reached “almost mythical proportions” and that the term “second impact syndrome” is misleading. He suggested that SIS be replaced with the term “diffuse cerebral swelling” (a finding that was present in most of the cases he reviewed), and that this extremely rare condition is caused by a single brain injury (emphasis mine). I strongly agree with him. Another point I agree with him is the following conclusion from his 2001 paper:

“Most cases of traumatic cerebral swelling, whether associated with a structural brain injury or not, have no prior evidence of head injury with ongoing symptoms that would support the concept of second impact syndrome as defined in the literature. In those cases that are presumed to represent SIS, the evidence that a prior head injury is a risk factor for this pathophysiological entity is not compelling.”
 
One of the other points McCrory makes in his 2001 article relates to when the initial clinical presentation does not match the objective severity of the injury because of a gradual progressive decline as opposed to an immediate and rapid one. He noted that scientists have commented on this phenomenon dating back to 1891 and that the condition is now commonly referred to as “talk and die syndrome” because the person is initially conversant but then gradually and fatally deteriorates (or comes close to fatally deteriorating). He noted that this delayed response occurs in about 15% of all cases of “severe” head trauma and is caused by an intracranial hematoma (bleed) in 75% of those cases. Sometimes, the bleed is present when the patient’s brain is initially scanned but sometimes the bleed is not observable until after a delay.

It has been over 10 years since McCrory published his 2001 paper and so I contacted him to determine if his views on SIS had changed. McCrory’s response to me on August 11, 2010 was as follows and I am reporting it for the first time here (with permission):

“My conclusions on 'SIS' are unchanged. I have continued to track the literature and claims made on this topic and while I am happy to accept that perhaps someone may be able to satisfy the criteria (as per the original article) and really have the condition, I am yet to see it.  It is worth observing that the US is the only place on the planet where SIS is actually discussed as an entity. Most other countries have moved on from this viewpoint years ago.”

Yet, in the U.S., the most recent (June 2012) Guidelines for Concussion Management in the School Setting, published by the New York State Education Department (SED), states as a fact that "Additionally, children and adolescents are at increased risk of protracted recovery and severe, potential permanent disability (e.g. early dementia also known as chronic traumatic encephalopathy), or even death if they sustain another concussion before fully recovering from the first concussion."  It's a classic example of mythology prevailing over data. As a disclaimer, I served as a formal advisor to SED regarding this document and have asked to be removed due to statements such as these (and others that I strongly oppose) making their way into the final document despite presenting the data described above. There is not even mention of at least a controversy being present about this issue.

McCrory and colleagues (2012) and Randolph and Kirkwood (2009) point out that delayed cerebral swelling does not require multiple injuries to occur, is most likely caused by a genetic susceptibility, and is extremely rare. For example, Randolph and Kirkwood cited statistical data showing that the rarity of this outcome in 10 years of American football (1997-2006) was 1 in 1.8 million players. Despite this rarity, millions of dollars are being spent on baseline cognitive testing, largely with the hopes of preventing this outcome. People are scared by the media reports and schools do not want to be held liable. Hence, the need to want to “do something” and testing fits the bill. The problem is that the bill (using conservative estimates), according to Randolph and Kirkwood, amounts to 36 million dollars over 10 football seasons to try and prevent a 1 in 1.8 million person outcome.

McCrory and I agree that it makes sense to hold patients out of play after they have suffered a concussion (consistent with the 2009 Zurich consensus guidelines on return to play after concussion; which were authored by McCrory) because it reduces that chances of further injury to the brain and/or other parts of the body (due to slower reaction time) but not because it is going to reduce the risk of post-traumatic cerebral swelling. I also agree with Randolph and Kirkwood that the best way to manage patients who suffer head trauma during sports (and to try and reduce a catastrophic outcome) is via close observation to detect a neurological decline and to immediately initiate medical/neurosurgical intervention if such a change is detected.

Related articles:

 1. Junior Seau Did Not Suffer 1500 Concussions
 2. CTE and Suicide Link is Premature Speculation

References:

McCrory PR, Berkovic SF. Second impact syndrome. Neurology; 1998;50(3):677-683.

McCrory P. Does second impact syndrome exist? Clinical Journal of Sport Medicine; 2001;11(3):144-149.

McCrory P, Meeuwisse W, Johnston K, et al. Consensus statement on concussion in sport - the Third International Conference on Concussion in Sport held in Zurich, 2008. Phys Sportsmed. 2009;37(2):141-159.

McCrory PR, Davis, G, Makdissi, M. Second Impact Syndrome or Cerebral Swelling after Sporting Head Injury. Current Sports Medicine Reports; 2012; 11(1),21-3.

Randolph, C. & Kirkwood, M. What are the real risks of sport-related concussion, and are they modifiable? Journal of the International Neuropsychological Society; 2009;15, 512–520 .

Saunders RL, Harbaugh RE. The second impact in catastrophic contact-sports head trauma. JAMA; 1984; 252(4):538-9.

Why You Need to Be Cautious When Shopping for Homeopathic Medications

I’m all for natural (homeopathic) treatment of health care problems if there is scientific evidence that it is effective.  As in the old days, people still rely on word of mouth recommendations from friends and family, casual review of non-scientific literature, and the advice of someone selling homeopathic products  to decide what medications to take to treat their ailments. These days, people have the added option of searching for such medication on the internet. No prescription is needed and the consumer proceeds at his/her own risk since the Food and Drug Administration does  not require that homeopathic medications undergo testing for safety and effectiveness.  

Many people are not aware of this and simply assume that since the medications are contained in a fancy looking bottle with scientific words, have stated indications for use, and/ or are sold on a website that looks legitimate, that they are safe and effective. While ineffective homeopathic medications may not directly cause harm, they can indirectly cause harm if the person fails substitutes an unproven treatment with a scientifically proven treatment. In some cases, this choice can mean the difference between life and death. A good example is How Fruits and Vegetables Killed Steve Jobs.

In perusing the internet tonight, I can across an advertisement for  oxydendrum arboreum (pictured above), also known as the sourwood or sorrel tree.  The ad states that it Is used for the following: “A remedy for dropsy - ascites and anasarca. Urine suppressed. Deranged portal circulation. Prostatic enlargement. Vesical calculi. Irritation of neck of bladder. Great difficulty of breathing. Tincture. Compare: Cerefolius (dropsy, Bright’s disease, cystitis).”

Let’s go through some of these terms. If you are not in the medical field, you may not realize that although this sounds fancy, that dropsy is an outdated term for edema or swelling. Ascities means fluid build-up in the space between layers that line the belly. Anasarca is extreme generalized edema. Suppression of urine output is obvious, as is difficulty breathing, prostate enlargement, and neck/bladder irritation. Vesical calculi is another terms for a bladder stone. Tincture refers to an herbal tincture, which is an alcoholic extraction of plant material by combining it with a liquid, typically alcohol. In other words, the medication is available in liquid form. It was also available in tablet form. On the last line, the ad compares the medication to another homeopathic treatment (Cerefolius) used to treat dropsy, cystitis (bladder inflammation), and Bright’s disease. Bright’s disease is an obsolete term used to describe acute or chronic kidney inflammation.

The use of obsolete words such as dropsy and Bright’s disease on a modern medical ad made me suspicious, so I did some more research and found this old advertisement from 1908:

Lo and behold what do we see?  Terms such as Bright’s disease, dropsical effusions (a reference to dropsy), anasarca, ascites, and edema as conditions that can be treated by a medication known as oxydendrine. Oxydendrine’s first ingredient is listed as oxydendrum, the plant being sold above on the internet today. Oxydendrine was the trade name for a medication that combined oxydendrum with other plant treatments including iris, sambucus,  and scilla (squill).  In 1908, it was being recommended that when used to treat dropsy due to heart disease, that the medication be taken with each meal and at bed time. For most people that is four times a day, which is a lot of pills. In fact, in severe cases, up to 8 pills a day were suggested. More pills equals more money. 

It does not seem that Oxydendrine was around long based on my own research into the topic, although I am happy to be provided any information to the contrary on that.  I can confirm that it was in use between 1907 and 1908. There is no scientific literature available in PubMed (repository of peer reviewed scientific research studies) that support the use of Oxydendrine or the primary ingredient, oxydendrum, for any medical treatments.  It seems like it was yet another type of patent medication such as Pink Pills for Pale People, which purported to treat various ailments without proof of safety or effectiveness.

 It also seems that information about Oxydendrine was taken from medical ads from over 100 years ago and used as the basis for a modern ad for a homeopathic treatment on the internet. While oxydendrum may indeed have some unknown medical properties, buyers beware when purchasing this substance or others that you have not properly vetted scientifically. If you need suggestions on how to do that, see my Five Ways for Evaluating Suspicious Medical Treatment Claims.

Cannibal Icepick Killer Luka Magnotta was Not Born Evil

While I may be wrong, I have never bought into the notion that people are born evil. It seems like a far too simplistic explanation and can serve as a way to conveniently ignore the ways in which negative life experiences (e.g., abuse, neglect, and poor parenting) combined with a lack of positive coping resources and other factors, can lead to depression, anxiety, low self-esteem, building to anger, rage, revenge fantasies, and abusive tendencies. For sure, people are born with biological temperament, but this temperament interacts with life experiences to shape who we are as individuals.

This brings me to the disturbing case of Luka Rocco Magnotta, who was widely known for videos he posted on Youtube involving the torturing and killing of kittens, followed by bestiality. More recently, he has recently been arrested for videotaping himself murdering a college student, Jun Lin, with an icepick, dismembering him, cannibalizing the corpse, engaging in sexual acts with it, posting the video on the internet, and mailing the body parts throughout Canada. Was he really born to do this? Nothing could have stopped it? He could have had no other type of life? I’m not buying it.

While new information is emerging daily, we know that Magnotta was born as Eric Clinton Kirk Newman on 7/24/82 in Scarborough, Ontario, to Don Newman and Anna Yourkin. At some point in childhood, it is known that he went to live with his grandmother in Lindsay, Ontario. While I have never met him, and I am not trained in psychological profiling, as a psychologist, my informal perspective on the matter is that the following played key roles in leading to where we are today. This perspective is based on media reports and is contingent upon the accuracy of the information in those reports.

1. Traumatic childhood: While details from his early childhood are very hard to come by, it has been reported (by one of his own family members) that his family life was very dysfunctional. His parents did not remain together. Based on comments he has made on the internet, he described a “horrible” childhood and did not feel loved by his family. He has been said to report on the internet that he had been sexually abused multiple times. Whether that is true or not is unknown at this time, but I am inclined to believe it given what we know about his sexually abusive behavior. While everyone responds to abuse differently,  some people hold in significant anger and seek ways to reverse roles, regain a sense of lost power,  and become the abuser against a helpless victim. This was popularized on the popular TV show, The Shield, when police captain David Aceveda responded to male rape by being abusive to women and eventually having the offender killed. As described in a prior blog post, animal abuse is often the precipitant to human abuse, and Magnotta engaged in numerous such actions against kittens and possibly other animals as well.

2. Not feeling loved: There are many victims of child abuse who go on to live successful and productive lives, which is aided by having a positive support system in place. For Magnotta, however, that does not appear to be the case. His father was reportedly not a significant presence in his life (he claims not to have even known him), his mother does not appear to have been around him much (and when she was they reportedly did not get along), and he was reportedly raised by a domineering grandmother. So now we have alleged abuse combined with what appears to be a lack of emotional support and further experiences of being under aversive control. Not a good combination. His grandmother has been described “…as a domineering personality who would beat up people with submissive personalities and get them to do what she wants.”  He was been quoted as saying about himself on the internet that “All he wanted was love.”

3.  Low self-esteem and narcissism:  A past filled with trauma and emotional neglect can easily lead to low self-esteem. One maladaptive defense mechanism for this is the development of narcissistic personality disorder, the essential features of which is a pervasive pattern of grandiosity, need for admiration, and lack of empathy that begins by early adulthood and is present in a variety of contexts. An ex-girlfriend described him as emotionally cold. He clearly was obsessed with his self-image, which he admitted during an audition for a plastic surgery show. He posted a large volume of model shots of himself online (just do a Google Image search to see this) which often show him in provocative poses,  fancy cars, and prominently worn designer clothes, all of which are designed to convey self-importance. He had more than 70 Facebook accounts about himself whereas the average person has one. He is known to have created numerous fake usernames on internet message boards in which he wrote about himself, spread rumors to create an additional sense of self-importance, and then denied them to draw further attention to himself. Despite all of his attempts at success, he was a continued failure, including his botched attempts to become a porn star and reality TV show contestant. These failures may have fueled his rage against society. Ironically, as police predicted, his narcissism led to his arrest when he was found in an internet cafe reading stories about himself.

4. Immersion in fantasy life:  While most people are able to differentiate fantasy from reality, some people become obsessed with fictional characters or develop fantasy relationships with non-fictional individuals. For example, he was known to be obsessed with James Dean, the famous actor best known for portraying a troubled teen with a dysfunctional family defying society in Rebel Without a Cause. Dean and Magnotta bear somewhat of a physical resemblance, which helps make the fantasy immersion more real. He became obsessed with plastic surgery, partly to help him look more like Dean, and he was known to pose like Dean in various photos. He spread rumors that he dated Karla Homolka, a famous Candia murderer who videotaped rape and murders she was involved with. He was known to use the name, Kirk Tramell, as an alias, a likely take on Catherine Tramell in the movie, Basic Instinct, who kills a lover with an icepick. His name change to Luka Rocco Magnotta on 8/12/06 reflects a combination of low self-esteem (not liking his original identity) and appears to reflect his latching on to fantasy characters. It is widely believed that he chose the name Magnotta after the character Vince Magnotta from a video game called Ripper. The character is a serial killer who butchers his victims. It is unclear where his cannibalistic urges came from but cannibal themes are actually quite prevalent in fiction and non-fiction, that he likely glommed on to one or more of these characters/individuals as a morbid curiosity.

In conclusion, I do not believe that Luka Magnotta was born evil. He may have been born with a negative temperament, but his crimes were shaped by negative events in his life, a lack of pro-social coping resources, an increasing sense of alienation, emotional pathology, revenge and power fantasies, immersion in fantasy life, and an obsession to draw attention to himself. Lastly, this article should not be taken as excusing his criminal actions, but as a way to explain his behaviors from a psychological perspective. For the record, I find his behaviors reprehensible, abhorrent, and believe he should be prosecuted and punished to the fullest extent of the law.

Related blog entries:
A Psychological profile of Wade Michael Page: The Sikh Shooter
A Psychological Profile of James Holmes: The Joker Killer
A Psychological Profile of Chardon School Shooter, T.J. Lane

Stopping Pet Abuse Helps Stop Cannibal Killers and Other Violent Criminals

There is a very good reason why society should have zero tolerance for the abuse of animals and children: because they are the essence of innocence, uncorrupted by society. However, the innocence that most of society cherishes in animals and children is exactly what makes them so alluring to sociopaths. They enjoy the power they have over a life that is defenseless and enjoy using that power to corrupt it. Animal abuse can involve killing, torturing, neglect and/or defiling the body of animal.

For many people who go on to commit unspeakable crimes against humans, non-human animals usually serve as the first targets. There are many examples of this. Jeffrey Dahmer, who became a human cannibal as an adult and experimented on his victims, dissected dead animals and impaled a dog’s head on a stake. Alleged murderer, Luka Rocco Magnotta, who allegedly stabbed a man repeatedly with an ice pick, dismembered him, and ate part of his body, began his criminal acts with animals, feeding a kitten to a python and also killing two kittens by placing them in a plastic bag, sucking the air out with a vacuum, dismembering them, and performing sexual acts with their body parts.

I can go on and on with many other revolting examples, but the two examples above make the point. While very difficult to hear and even write about, society needs to make the capture, prosecution, and sentencing of animal abusers a much higher priority. For example, it is amazing to me that Magnotta was never arrested by law enforcement for his kitten murders despite widespread outrage by many on the internet to identify and stop him. If he had been arrested and prosecuted for kitten murders, then the person he killed would probably still be alive today provided a meaningful sentence was implemented. 

Fortunately, most states have felony provisions for animal abuse, but it is unacceptable that three do not: Idaho, North Dakota, and South Dakota. Across all states, the average maximum jail time for animal abuse is 47.2 months (about 4 years). The states that take this issue the most seriously are Alabama and Louisiana (10 year maximum sentences) and the state with the shortest sentence is North Carolina (6 months maximum sentence). The average fine for animal abuse across the U.S. is $24,420. However, that average is significantly skewed by Colorado imposing a maximum fine at $500,000, followed by Arizona at $150,000 and Oregon at $100,000. The fines from most states are actually $5,000 or less. The lowest maximum fine is $1,000, which occurs in North Carolina, Arkansas, Rhode Island, and South Dakota. One state (Tennessee) does not appear to have a fine.

Only 14 states have laws that allow for a temporary or permanent ban on animal ownership as part of sentencing. That means 36 do not. Only 7 states have laws that allow allows for animals to be included in protective orders (known as pet protective orders). That means 43 do not. Thirty-two states include mandated counseling for animal abusers. That means 28 do not.

There are a few things worth noting from the existing penalties for animal abuse, which is courtesy of Pet-Abuse.com. First, in many states, it costs more to purchase a pure breed animal than it costs to torture and kill it. That should never be the case and should be changed. Second, all states should have mandated counseling for animal abusers, allow for a permanent ban on pet ownership (after you abuse a pet you should not get a second chance), and should allow for pet protective orders. Third, the states of South Dakota and North Carolina appear to take animal abuse the least seriously since the former does not include animal abuse as a felony and has one of the lowest fines while the latter has the shortest maximum jail sentences and one of the lowest fines.

Of course, people need to use common sense when it comes to what constitutes a crime in the death of animals, since there are people who have licenses to hunt and fish, companies that slaughter animals for food, and who among us has not swatted a fly in the house to prevent the spread of germs? All of these instances, however, are vastly different from somebody who kills an animal for the express purposes of gaining pleasure from watching it suffer and/or die. These are the people who need to be identified, prosecuted, and stopped, not only in the pursuit of justice, but also to prevent hard to human beings.

Children need to be taught from early on to respect life and to follow the Golden Rule. This means no killing of animals, including insects, purely for pleasure or entertainment. This teaches empathy, which is something lacking in many people who go on to become violent criminals.

If you want to see just how common animal abuse is, just do a zipcode search in the national searchable database at Pet-Abuse.com to see the shocking results near you. Those very people may go on to abduct and kill one of your family members or someone in your community. Visit Pet-Abuse.com to find out more about how you can help. 

Why All of the Recent Human Cannibalism?

Warning: This blog entry contains information that is graphic and disturbing. Do not read further if you are not so inclined. Ta Ta.

It began on Saturday, 5/26/12. The nation was shocked to hear that 31-year-old Rudy Eugene, a resident of Ft. Lauderdale, ran naked down the Miami Causeway, came across a 65-year-old homeless man (Ronald Poppo) lying innocently in the shade, pummeled him in broad daylight, and devoured most of his face.

I had actually recently posted a blog entry about my personal observation of an obese, naked, mentally ill man rolling around Ft. Lauderdale Beach for years, but the Rudy Eugene story was something well beyond that. There are news reports that Eugene had a history of aggression, paranoia, religious pre-occupation, and poverty. Given his age, it is possible that he may have had a mental illness such as schizophrenia, but even if this is true, cannibalism is not common in schizophrenia. It is unclear if Eugene was intoxicated at the time and there has been much speculation that he showed tell-tale signs of delirium and aggression on that day due to ingestion of bath salt stimulants that he may have ingested at a Miami concert the night before.

Then on 5/30/11, it was revealed that a 29-year-old gay porn actor named Luka Rocco Magnotta (real name Eric Clinton Newman), who was known for killing kittens and posting the videos online, shipped human body parts (i.e., foot, hand) to political parties in Canada. I joked that night that I was scared to see what tomorrow’s news will bring. Indeed, on 5/31/12, it was revealed that Magnotta videotaped himself killing the victim, eating parts of him, and then releasing the video on the internet. This was after his animal abuse exploits went unaccounted for. And if that wasn’t enough, a 21-year-old Maryland college student named Alexander Kinyua was arrested the same day for killing his 37-year-old housemate, cutting him up, eating his heart, and part of his brains.

That’s three human cannibal stories in less than one week, which is extremely bizarre.
As a scientist who studies the causes of human behavior, I wanted an explanation as to why this was happening and why someone would ever decide to eat another human besides starvation in extreme conditions. Below is a basic summary of what I have found, thought about, and hypothesized, to understand this issue more but I welcome your comments as well because I sure do not have all the answers.

To begin with, the word cannibal comes from the fact that Christopher Columbus wrote about ferocious people from the Carribean islands and parts of South America, known as the Caniba, who ate people. Some anthropologists believe that cannibalism was very common in pre-historic times. There is even a story of cannibalism in the Bible (2 Kings: 25-30). As a neuropsychologist, I am also familiar with the incurable neurodegenerative prion disease known as kuru, which was transmitted when members of the Fore tribe of Papua New Guinea consumed the dead.

There have been many stories throughout history of cannibalism due to necessity from famine. Many may be surprised to know that this happened among U.S. colonists, who dug up corpses for food. One colonist even killed, salted, and ate his pregnant wife. Many are more familiar with the cannibalism among the Donner party, a U.S. settlement group in the mid-1800s. Cannibalism occurred all over the world, such as in Nazi concentration camps, Japanese troops in WWII, China and North Korea (due to famine), and many others. 

Then there are cannibal stories popularized in our culture, such as the hag in Hansel and Gretel who tries to cook and eat little children. We are told of Count Dracula, who didn’t actually eat people, but bit their necks and sucked their blood. The Dracula craze has never died off and is popularized in modern times by the Twilight book and movie series. Zombies have also been very popular as popularized the Living Dead series and their quest for eating human flesh. Then there is the story of Leatherface, in the Texas Chainsaw Massacre, who was a cannibal living amongst a family of cannibals. Leatherface took things one step further and wore the skin of his victims. Perhaps the most famous modern fictional cannibal is Hannibal Lecter, who was famous for eating his victim’s faces (sound familiar?).

Many people perform a very limited form of self-cannibalism, such as biting their fingernails and toenails and eating them although some dispute that this is true self-cannibalism. Some people eat their own skin after it has peeled off from a bad sunburn. Some people also eat their own hair, which is known as trichophagia. Some people eat their own scabs. Some animals (e.g. goats) are known to engage in self-cannibalism as well such as eating the placenta of their young but this is for nutritional benefit. The short-tailed cricket is known to eat its own wings. The North American rat snake has been known to try to consume its own body.

Back to humans, most people all familiar with the cannibalistic crimes of Jeffrey Dahmer. One of the most disturbing cases is that of Albert Fish, who cannibalized young children and tormented parents by sending them notes vividly describing his crimes. Andrein Chikatilo used cannibalism as a way to gratify his sexual needs, in an extreme extension of Count Dracula. Just a few years ago (2008), Tim McLean was savagely decapitated on a Greyhound bus by 40-year-old Vince Weiguang Li, who then proceeded to eat parts of the body.

This year, a German researcher (Hamalainen, 2012) reported the first case of a non-human primate (gray mouse lemur) cannibalizing an adult member of the same species. The body cavity was torn open and the inner organs eaten. The skull had been broken and the brains were consumed. The spinal cord was being devoured as well. It is unknown if the cannibal lemur had killed its victim or if it was scavenging. The authors concluded that “Cannibalism may confer immediate nutritional and energetic benefits to the cannibal and therefore might have adaptive value at the individual level.” Previously, non-human primates had only been known to cannibalize the young. Some insects (e.g., praying mantis), fish, amphibians, and birds have been known to cannibalize adults members of the same species.

Overall, if you think about it, cannibalism has been practiced all over the world and throughout history, sometimes due to famine, sometimes due to crime, and sometimes due to mental illness. It occurs in humans, insects, and various other non-human animals including primates. It is popularized in our culture through scary stories told to children and horror movies designed to scare adults. It is also relatively common for people to eat parts of their own skin (e.g., nails, hair, peeled skin) and scabs. My theory is that what  happened in the Rudy Eugene case is that someone with a probable prior mental illnesses and/or certain form of drug intoxication caused him to become disinhibited and regress to a very primitive evolutionary state. Whether this is what happened in the other two cases is less clear given that not enough information available. Why there have been three cases in less than one week is also unclear but one has to wonder if there is a copycat crime element to this in some people who are already seriously mentally ill.

References:

Hamalainen, A. (2012). A Case of Adult Cannibalism in the Gray Mouse Lemur, Microcebus murinus. American Journal of Primatology 00:1–5 (2012).
Wikipedia cannibalism page
Wikipedia self-cannibalism page