Racist Costumes to Egging Hazards: The Science of Halloween
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Halloween isn't just an occasion to put on zombie makeup and binge-eat candy. Some researchers embrace Oct. 31 as an opportunity for serious study. From an analysis of racist costumes to an assessment of the hazards of egg throwing, here are a few strange chapters from the annals of Halloween science.

No fear: Woman immune to haunted houses

For years, scientists have been intrigued by a woman who doesn't seem to experience fear. Now in her late 40s, the patient known as SM suffers from a rare condition called Urbach-Wiethe disease that has destroyed her amygdalae. This pair of almond-shaped structures in the brain is associated with fear. [7 Weirdest Medical Conditions]

A few years ago, a group of scientists conducted a battery of unusual tests to try to scare SM. They exposed her to live snakes and spiders. They made her watch clips from "The Ring," "The Shining," "The Silence of the Lambs" and other horror movies. And during Halloween, they took SM to a haunted house set up inside the gothic Waverly Hills Sanatorium in Kentucky. In the journal Current Biology in 2011, the researchers noted SM's bizarre behavior on the tour:

"From the outset, SM voluntarily led the entire group through the haunted house, showing no signs of hesitation while walking around corners or into dark hallways. As the other members of the group lagged behind her, she would repeatedly call out, 'This way guys, follow me!' The hidden monsters attempted to scare SM numerous times, but to no avail. She reacted to the monsters by smiling, laughing or trying to talk to them. In contrast, their scare tactics typically elicited loud screams of fright from the other members of the group."

In the haunted house, SM approached the monsters and tried to touch them. She actually scared one of the characters by poking the person in the head, the researchers said. Before, during and after the haunted house tour, SM reported fear ratings of 0. Instead of fear, she claimed to have a high level of excitement and enthusiasm throughout, describing the experience as similar to the enjoyment she gets while riding a rollercoaster.

Costumed college kids are probably drunk

These studies might have made the cut for Live Science's annual roundup of obvious findings. Between 1978 and 1982, researchers polled more than 1,000 students from two colleges in upstate New York about their Halloween activities. Did they wear a costume? Did they drink? The researchers found that, yes, for college students, dressing in costume is linked to the use of alcohol. About 82 percent of students wore costumes on Halloween, and among that group, 87 percent reported that they drank, according to the findings published in the journal Adolescence in 1993. [13 Halloween Superstitions & Traditions Explained]

Another group of researchers, from Virginia Tech, revisited this rich topic of celebratory drinking with a study published in the journal Environment and Behavior in 2007. But rather than rely on the college students' self-reports, the intrepid researchers went out into the field equipped with breathalyzers on Halloween and St. Patrick's Day. The students who said they were drinking because they were celebrating these holidays had high levels of intoxication, with a mean blood alcohol concentration of 0.096, the researchers found. (For comparison, the legal limit for driving in the United States is 0.08.) Students who were not celebrating, meanwhile, had an average blood alcohol concentration of 0.074.

Eggs can hurt you

Projectile eggs have become part of the repertoire of Halloween mischief. But did you know that a raw egg "can act as a substantial missile" and that it fits right into the eye socket "like a squash ball"? (Apparently, squash players are prone to eye injuries.) That's what a group of doctors wrote in a letter to the journal Eye in 2003, highlighting three cases of eye injuries wrought by flying eggs.

Since an egg can fit so nicely into the eye cavity, "relatively little force is therefore dissipated to the orbital rim, the egg transferring most of its kinetic energy directly to the globe on impact." Ouch.

Maybe you could dress up like a lab scientist or aviator and wear protective goggles. Or, better yet, just refrain from throwing eggs. Eye injuries aside, egging can still take a dangerous turn. Just in New York, at least two dozen people were seriously hurt or killed in stabbings, shootings, beatings or accidents that started out as "egg-throwing confrontations" around Halloween since 1984, The New York Times reported in 2010

Racist and sexist Halloween costumes abound

The public shaming of people wearing racist Halloween costumes has become almost as much of an annual ritual as trick-or-treating. Who could forget the 25-year-old white Florida man dressed as Trayvon Martin last year? Already, pictures of revelers in misguided Ray Rice costumes are invading Facebook feeds and drawing the ire of TV pundits.

Why do people think these kinds of costumes are OK each Halloween? A few years ago, a group of sociologists led by Jennifer Mueller, now an assistant professor at Skidmore College, sought an explanation. The researchers had dozens of college students write down their observations around Halloween in a journal, and they found that racialized costumes are quite common on American campuses. While some students were appalled at seeing their friends or strangers in blackface, others didn't seem all that alarmed. Some were actually amused. One white student wrote that seeing her two white male friends "covered in black paint from head to toe" to dress up as tennis stars Venus and Serena Williams was "the funniest thing [she] had seen in a long time."

Another white male student reported that one of his friends (also white) revealed plans to dress up as "the black girl from [the film] 'Coyote Ugly'" for Halloween. (That character was played by Tyra Banks.) The student wrote: "He then elaborated, 'All I'll have to do is paint my skin and smell bad. Oh, and it'll help if I act like I don't know how to swim.' Everyone got a good laugh out of it."

Dressing up on Halloween might allow people to let go of their inhibitions and defy social norms, the researchers wrote, but in this context, some celebrators might be under the impression that they get a free pass to be offensive. Most of the white students who participated in the study "actively suspended their criticisms or behaved in wholly uncritical ways" despite the clear intentions of some of their fellow students to caricature and degrade blackness with their costumes, Mueller and colleagues wrote in the journal Qualitative Sociology in 2007. And even among the students who seemed upset by racially insensitive getups, few reported that they offered their criticisms out loud.

Halloween is also an annual reminder that gender stereotypes still dominate, even among young kids. Around Halloween in the late 1990s, Adie Nelson, a sociology professor at the University of Waterloo in Canada, looked at 469 children's Halloween costumes in craft stores, department stores and specialty Halloween stores. Less than 10 percent of those costumes could be considered gender neutral, and most of those were for infants. Nelson found that feminine costumes had a predictably narrow range: beauty queens, princesses, cupcakes and brides.

"Decades after the second wave of the women's movement, you would expect more of a gender-neutral range of costumes," Nelson told The New York Times in 2006. Her study was published in 2000 in the journal Psychology of Women Quarterly.

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