"Do you like feet? Would you like a free brain scan and 90$?"
When Allison Leeming posted those words on the website Reddit, she hoped the boldness of her opening sentence would catch a few eyes.
Previous attempts to recruit foot aficionados received responses that were "not that great," the University of Ottawa clinical psychology PhD candidate said.
But she didn't expect to set a small corner of the internet ablaze with her latest foray to find test subjects for a new brain imaging study on erotic responses.
"It blew up," Leeming, who works at the Royal Ottawa Hospital, told CBC Radio's All In A Day.
"You should see my email inbox. It is absolutely overwhelmed. I think I'm gonna break the hospital internet."
The study won't just look at harmless erotic urges that would elicit a giggle at a dinner party.
As part of the study, Leeming and the Royal are looking for male subjects from three groups: those with no strong unusual erotic interests, those with strong interests in women's feet, and males with strong erotic interest in prepubescent girls.
Previous studies examined pedophilic men with lengthy criminal histories, especially involving assault, but Leeming hopes to exclude individuals with frequent run-ins with the law this time around.
Their checkered pasts can make comparisons "muddy," difficult to attribute results "to criminality versus pedophilic interest," she said.
By adding men who love feet into the mix, the study hopes to put fetishism under the microscope, or rather, brain scanner.
"Fetishism is really not well known in terms of what it looks like in the brain so including that third group is also really unique," she said.
Foot fetishes 'really, really popular'
Alongside the study's lead investigator Michael Seto, Leeming believes pedophilic brains will still show noticeable differences — in structure and function — when placed side-by-side to other sexual fetishes.
"[The research] allows us to test hypotheses for these differences that have been shown in previous research," Seto said. "Are they unique to pedophilia? Or is it something more general about having unusual sexual interest?"
Not only are foot fetishes legal, but according to Leeming they're "really, really popular in the community," which made them a good fit for their work.
It's also a fetish with a focus on a person or object rather than a specific sexual act, another important distinction when comparing with the two other groups.
Seto said it's an under-researched topic and that, beyond the expenses of neuroimaging, can be an uphill battle due to certain barriers.
"It's not always easy to be able to recruit people, especially if they have unusual sexual interests," he said. "They might be concerned about being embarrassed or being identified."
The researchers have recruited some men receiving treatment for their pedophilic urges and are in peer-support groups; individuals who seek answers and want to be part of the fight, Leeming said.
She will be the only one to have face-to-face interactions with participants, which she hopes encourages some to come forward.
Those who do will be interviewed, fill out questionnaires, and have their brain scanned before reviewing the pictures.
While the bulk of the research remains ahead, Leeming believes the huge interest in her Reddit post has at least started her study off on the right foot.
"We've really seen an increase in men, especially with interest in feet coming forward," she said. "Now that all of the outpatient groups for sexual interest in children have moved online, it's a lot easier to access for some people. … Things are looking good."