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hearing

Scientists Are Figuring Out Why Some People Can ‘Hear’ The Voices of The Dead

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Scientists have identified the traits that may make a person more likely to claim they hear the voices of the dead.

According to new research, a predisposition to high levels of absorption in tasks, unusual auditory experiences in childhood, and a high susceptibility to auditory hallucinations all occur more strongly in self-described clairaudient mediums than the general population.

 

The finding could help us to better understand the upsetting auditory hallucinations that accompany mental illnesses such as schizophrenia, the researchers say.

The Spiritualist experiences of clairvoyance and clairaudience – the experience of seeing or hearing something in the absence of an external stimulus, and attributed to the spirits of the dead – is of great scientific interest, both for anthropologists studying religious and spiritual experiences, and scientists studying pathological hallucinatory experiences.

In particular, researchers would like to better understand why some people with auditory experiences report a Spiritualist experience, while others find them more distressing, and receive a mental health diagnosis.

“Spiritualists tend to report unusual auditory experiences which are positive, start early in life and which they are often then able to control,” explained psychologist Peter Moseley of Northumbria University in the UK.

“Understanding how these develop is important because it could help us understand more about distressing or non-controllable experiences of hearing voices too.”

He and his colleague psychologist Adam Powell of Durham University in the UK recruited and surveyed 65 clairaudient mediums from the UK’s Spiritualists’ National Union, and 143 members of the general population recruited through social media, to determine what differentiated Spiritualists from the general public, who don’t (usually) report hearing the voices of the dead.

 

Overall, 44.6 percent of the Spiritualists reported hearing voices daily, and 79 percent said the experiences were part of their daily lives. And while most reported hearing the voices inside their head, 31.7 percent reported that the voices were external, too.

The results of the survey were striking.

Compared to the general population, the Spiritualists reported much higher belief in the paranormal, and were less likely to care what other people thought of them.

The Spiritualists on the whole had their first auditory experience young, at an average age of 21.7 years, and reported a high level of absorption. That’s a term that describes total immersion in mental tasks and activities or altered states, and how effective the individual is at tuning out the world around them.

In addition, they reported that they were more prone to hallucination-like experiences. The researchers noted that they hadn’t usually heard of Spiritualism prior to their experiences; rather, they had come across it while looking for answers.

In the general population, high levels of absorption were also strongly correlated with belief in the paranormal – but little or no susceptibility to auditory hallucinations. And in both groups, there were no differences in the levels of belief in the paranormal and susceptibility to visual hallucinations.

 

These results, the researchers say, suggest that experiencing the ‘voices of the dead’ is therefore unlikely to be a result of peer pressure, a positive social context, or suggestibility due to belief in the paranormal. Instead, these individuals adopt Spiritualism because it aligns with their experience and is personally meaningful to them.

“Our findings say a lot about ‘learning and yearning’. For our participants, the tenets of Spiritualism seem to make sense of both extraordinary childhood experiences as well as the frequent auditory phenomena they experience as practising mediums,” Powell said.

“But all of those experiences may result more from having certain tendencies or early abilities than from simply believing in the possibility of contacting the dead if one tries hard enough.”

Future research, they concluded, should explore a variety of cultural context to better understand the relationship between absorption, belief, and the strange, spiritual experience of ghosts whispering in one’s ear.

The research has been published in Mental Health, Religion and Culture.

 



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Creating Hallucinations Without Any Drugs Is Actually Surprisingly Easy

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The human brain is a remarkable thing; our most complex machines are not even close to competing with our powers of higher consciousness and ingenuity. And yet, those 80 billion or so neurons are also incredibly fragile.

 

If the tiniest thing goes wrong with a particular connection – maybe something misfires, or a certain neural pathway is blocked – things can fall apart very quickly.

And, oddly enough, even without any injuries or structural malfunctions, the human brain can get weird all by itself – turns out, it’s surprisingly easy to trick it into seeing and hearing things that aren’t actually there.

We’re not talking about taking a bunch of drugs to make yourself hallucinate. The brain can do all that on its own – you just have to know how to manipulate it.

As demonstrated by the guys in this 2016 Scam Nation video on YouTube, if you create a situation of intense sensory deprivation using some common household objects, you can induce some really strong hallucinations that mess with both your sense of sight and sound. 

You’re going to need:

  • Sheets of light, white paper
  • Cotton padding
  • Rubber bands
  • Stationery, including scissors, tape, a stapler, and string
  • A YouTube video of old television white noise or static that runs uninterrupted for at least 30 minutes
  • Noise-cancelling headphones

 

Watch the video to find out how they use each of these things to basically deprive themselves of any sensory input. The effects usually start to show after about 10 to 30 minutes.

After 20 minutes, the Scam Nation guys reported seeing “blooms of colour” – like those you see when you rub your eyelids – that would soon form shapes, such as dinosaur silhouettes, jellyfish, and the Eye of Sauron.

One heard screams, and the other heard laughter.

Sounds like nonsense? Well, sure, we have to take the word of two dudes on YouTube for this particular scenario, but what they’re doing actually follows the principles of a scientific phenomenon known as the Ganzfeld effect.

The Ganzfeld effect describes how when you’re exposed to “an unstructured, uniform stimulation field” – such as seeing blackness and hearing constant television static – your brain responds by amplifying neural noise in an effort to find missing visual signals.

This can result in both visual and aural hallucinations like the guys in the video describe. 

Of course, every person will experience the effect in different ways.

 

When Derek Muller from Veritasium tried his own version of sensory deprivation – locking himself in a pitch-black, ultra-quiet anechoic chamber for 45 minutes – he debunked the myth that the lack of stimulation would send you mad, but did report a few odd sensations. 

“Perhaps the weirdest thing I noticed was the sense of my heart,” he says.

“I just felt like it was pumping really hard, and I could feel, almost like the blood pushing up through me. It wasn’t like I was hearing it, it was like I was feeling it. And I was feeling as though, in a way, my heart was shaking my body. That was something weird.”

In this situation, Derek didn’t exactly experience hallucinations, but what he describes with his heart does suggest his brain was amplifying things in the absence of any stimuli.

Interestingly, researchers demonstrated a similar effect in an experiment in 2015, where they asked volunteers to stare into each other’s eyes for 10 minutes straight.

“The participants in the eye-staring group said they’d had a compelling experience unlike anything they’d felt before,” Christian Jarrett reported for the British Psychological Society’s Research Digest at the time. 

It’s an imprecise science, to be sure, because every person’s brain responds differently to the weird things we throw at it (figuratively), but you could give the Scam Nation method a try and see what happens to you. Just, if the Supreme Being from Time Bandits gives you a hard time, don’t blame us, okay?

A version of this article was first published in April 2016.

 



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Our World Really Has Been Quieter During The Pandemic, Study Reveals

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The coronavirus pandemic has been tough on so many people in so many ways, but we’ll take what bits of good news we can at this point – and one benefit of social distancing and household lockdowns is that we’re being exposed to much less environmental noise.

 

Researchers looked at decibel data collected by 5,894 Apple Watch and iPhone owners, covering over half a million daily noise levels in total, before and after the start of the pandemic. Daily average sound levels were down almost 3 decibels in March and April, compared with January and February.

Whatever the other effects of the virus and our response to it, that’s a positive development as far as our ears are concerned – chronic sound exposure is associated with hearing loss, cardiovascular disease, and other health issues.

“That is a huge reduction in terms of exposure and it could have a great effect on people’s overall health outcomes over time,” says exposure scientist Rick Neitzel, from the University of Michigan. “The analysis demonstrates the utility of everyday use of digital devices in evaluating daily behaviours and exposures.”

The average 3 decibel drop represents a halving of the sound energy that the participants were exposed to – across all the samples, the fall was from a daily average of 73.2 dBA before lockdown measures were introduced to 70.6 dBA afterwards. Anything above the 70 dBA mark comes with the risk of damaging hearing over time.

 

Initially the largest drop in sound exposure was seen on weekends, but as people started working from home, this began to level off. As lockdowns came into force there was little difference between weekends and weekdays in terms of sound levels.

The data were collected over four different states in the US, and the patterns of noise reduction reflected the lockdown measures put in place by each of these regions, with some shutting down more completely than others.

“California and New York both had really drastic reductions in sound that happened very quickly, whereas Florida and Texas had somewhat less of a reduction,” says Neitzel.

The results come as part of the ongoing Michigan Public Health Apple Hearing Study (which you can also sign up for). One key advantage of using wearables and phones for this monitoring is that it’s very personal and specific – it’s a much better reflection of an individual’s noise exposure than sound sensors set up in public spaces, for example.

Newer versions of the Apple Watch and iPhone come with noise measuring built in, and will warn users if they’re exposed to an unsafe level of noise for a prolonged period of time. Bear in mind that in this study, the data are only representative of iPhone and Apple Watch users, so a broader sample would be needed to get a more representative look at noise levels.

The researchers say this kind of always-on, personalised noise monitoring allows for more detailed analysis – data can be broken down to provide information categorised by an individual’s age, location, or existing conditions, for example.

“These are questions we’ve had for years and now we’re starting to have data that will allow us to answer them,” says Neitzel. “We’re thankful to the participants who contributed unprecedented amounts of data. This is data that never existed or was even possible before.”

The research has been published in Environmental Research Letters.



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Naked Mole Rats Would Deafen Themselves if They Weren’t Already Hard of Hearing

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Hearing loss in humans can make life challenging in our hustle-bustle landscape. But when your world is literally as silent as a grave, being hard of hearing just might be something of a superpower.

 

For naked mole rats and their cousins, the loss of genes that would usually amplify noises is another extraordinary adaptation in a long line of tricks they’ve evolved to withstand the stresses of a subterranean lifestyle.

Pale and bald with saggy skin, big teeth and rudimentary eyes, these thumb-sized East-African mammals aren’t exactly blessed in the looks department. Not that it matters when you spend virtually your entire existence in darkness.

Being social animals, what does matter is an ability to communicate with other members of your clan in some way, so it shouldn’t be all that surprising that mole rats like them tend to be chatty little critters.

What is surprising is that all of that talk falls on ears that might have trouble hearing much of it.

“Naked mole rats are constantly chirping and squeaking,” says neuroscientist Thomas Park, from the University of Illinois Chicago.

“We were curious about their hearing since they are so vocal, but research had suggested that their hearing is actually quite bad.”

Just how bad their hearing is – and why – is the question Park and his colleagues set out to answer.

 

Using similar technology to that used to test the hearing of human newborns, the researchers measured the response of auditory nerves to sound stimulation in two species of mole rat, the naked mole rat (Heterocephalus glaber) and a slightly more dapper cousin, the Damaraland mole rat (Fukomys damarensis).

As a point of comparison they also measured the hearing in mice in the same way.

Much as they expected, their hearing wasn’t the best. In fact, it was so bad, if their subjects were humans they’d easily qualify for hearing aids.

Typical human hearing is anywhere from 20 hertz to 20 kilohertz, though for those of us hitting middle age anything above 14 kilohertz is a gift.

Subjected to tones ranging from 250 hertz to 6 kilohertz, the two naked mole rats they tested could only detect sounds between 500 hertz and 4 kilohertz. The four Damaraland mole rats they tested on came out even worse, topping out at 2 kilohertz.

For mice, the hearing went all the way up to 32 kilohertz. Though they also couldn’t pick up the same, smooth bass tones as the mole rats, hearing nothing below 6 kilohertz.

 

Given so few mole rats were used in the study, it’s possible they just happened to snatch up a couple of unlucky grandpas. But the hearing test was just for starters.

Confident that previous studies were on the money as far as their poor hearing goes, the team turned their attention to the genes behind the mole rat’s hearing.

Again, previous research had suggested there was something going on. A look at the transcriptome – the library of genes expressing themselves in particular tissues – had already revealed genes related to hearing that evolution had seemed to favour.

With all of this in mind, the researchers dug even deeper, comparing the kinds of changes in half a dozen mole rat genes with mutations responsible for hearing impairment in humans.

The ultimate cause of the mole rat’s reduced range of hearing can be traced to the absence of a functional cochlear amplifier, an otherwise common biological system among vertebrates.

This arrangement of microscopic hairs improves sensitivity to both frequency and volume. Two things mole rats, it seems, really have no need for.

 

In fact, not only do they have no need for better hearing, having it just might damage their sensitivity to the narrow range of frequencies they do have.

“Because the naked mole-rats lack functional cochlear amplification, the sounds they hear don’t ever get up to a level where they are lethal to hair cells, and so the naked mole-rats can withstand this constant cacophony without going totally deaf,” Park says.

“They are the only mammals we know of that lack cochlear amplification.”

It’s mostly speculation for now, but further research could help confirm the cause of their hearing loss.

Standing alone in its field is nothing all that new for this odd little underground rodent. Cancer isn’t a word you’ll find in their dictionary. They not only tolerate high levels of carbon dioxide and the irritating effects of its acidic touch, they rely on the gas for their health.

And who needs to shout commands when you can just force your family into looking after your babies through the mind-controlling pheromones leaking out of your faeces?

Further research into their unique senses might help us better understand how hearing loss occurs in humans, or even how we might go about repairing it.

It’s just one more thing that makes the mole rat more than just a pretty face.

This research was published in Current Biology.

 



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A Man Lost His Hearing And Suffered Inflamed Eyes After Getting a Standard Back Tattoo

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Getting inked isn’t without its share of risks. We’re not just talking regrets over your ex’s name either – there’s the slim chance of an allergic reaction, possibility of infection, and even the potential you’ll hide warning signs of cancer.

 

Thankfully, hearing loss, lung lesions, and eye inflammation aren’t usually concerns for the freshly tattooed. But when specialists at Fukuoka University Hospital in Japan encountered these symptoms in a 35-year-old male patient, they were able to link them back to his recent art piece.

Tattoos were probably the furthest thing from the patient’s mind when he presented to the Department of Ophthalmology after suffering abnormal vision for the past four months.

Doctors diagnosed the man with an inflammatory condition called uveitis, which gets its name because it affects the middle layer of tissue in the eye’s wall called the uvea.

Without any obvious signs of trauma or infection that could be blamed for the condition, medical specialists suspected that accumulations of inflammatory cells called granulomas might be behind the swelling and redness.

The condition itself is referred to as sarcoidosis. Although it’s associated with an immune response, its trigger isn’t always obvious.

Sure enough, blood tests showed elevated levels of the sorts of hormones expected in an immune response. A CT scan of the patient’s chest also revealed a bunch of tiny nodules, another feature common in cases of sarcoidosis.

 

Shortly after receiving treatment, the man came down with yet another symptom – a loss of hearing in both ears.

Though not overly common, a quick look through the literature reveals cases where those granuloma parties can accumulate around nerves in the skull and around the face, interfering with hearing.

Fortunately a couple of weeks on corticosteroids did the trick, clearing up not just the eye inflammation but returning the patient’s hearing.

As to the cause, while investigating his symptoms the doctors took a close look at the six-month-old tattoo on the man’s back.

They found signs of granulomas in the skin eruptions within the tattoo’s inked lines. It’s not uncommon to find these painless lesions popping up as a reaction to the metals in certain inks, especially months following injection.

It’s probably not all that surprising that tattoos can occasionally trigger reactions in hypersensitive individuals. In recent years we’ve learned more about how white blood cells are the caretakers of the ink, going as far as passing it down through the generations.

With the immune system playing such a central role in maintaining a tattoo, there’s bound to be cases where biology goes a little astray.

 

Luckily the course of corticosteroids cleared up the patient’s tattoo granulomas too, leaving him with skin as clear as his hearing.

In this case, the link between the back tattoo and sarcoidosis isn’t confirmed beyond all doubt. Nonetheless, the authors advise signs of granulomas in relatively recent ink should be a reason to look for signs of inflammation elsewhere in the body.

Just one more thing to keep in mind when getting your partner’s name inked into your back.

This research was published in BMJ Case Reports.

 



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Creating Hallucinations Without Any Drugs Is Surprisingly Easy

in Science News by


The human brain is a remarkable thing. It can do things our primate relatives are thousands – maybe even millions – of years of evolution away from, and our most complex machines are not even close to competing with our powers of higher consciousness and ingenuity.

 

And yet, those 80 billion or so neurons are also incredibly fragile.

If the tiniest thing goes wrong with a particular connection – maybe something misfires, or a certain neural pathway is blocked – things can fall apart very quickly.

And, oddly enough, even without any injuries or structural malfunctions, the human brain can get weird all by itself – turns out, it’s surprisingly easy to trick it into seeing and hearing things that aren’t actually there.

And no, we’re not talking about taking a bunch of drugs to make yourself hallucinate. The brain can do all that on its own, you just have to know how to manipulate it.

As demonstrated by the guys in this 2016 Scam Nation video on YouTube, if you create a situation of intense sensory deprivation using some common household objects, you can induce some really strong hallucinations that mess with both your sense of sight and sound. 

You’re going to need:

  • Sheets of light, white paper
  • Cotton padding
  • Rubber bands
  • Stationery, including scissors, tape, a stapler, and string
  • A YouTube video of old television white noise or static that runs uninterrupted for at least 30 minutes
  • Noise-cancelling headphones

 

Watch the video to find out how they use each of these things to basically deprive themselves of any sensory input, and have a try yourself.

The effects usually start to show after about 10 to 30 minutes.

After 20 minutes, the Scam Nation guys reported seeing “blooms of colour” – like those you see when you rub your eyelids – that would soon form shapes, such as dinosaur silhouettes, jellyfish, and the Eye of Sauron.

One heard screams, and the other heard laughter.

Sounds like nonsense? Well, sure, we have to take the word of two dudes on YouTube for this particular scenario, but what they’re doing actually follows the principles of a scientific phenomenon known as the Ganzfeld effect.

The Ganzfeld effect describes how when you’re exposed to “an unstructured, uniform stimulation field” – such as seeing blackness and hearing constant television static – your brain responds by amplifying neural noise in an effort to find missing visual signals.

This can result in both visual and aural hallucinations like the guys in the video describe. 

Of course, every person will experience the effect in different ways.

 

When Derek Muller from Veritasium tried his own version of sensory deprivation – locking himself in a pitch-black, ultra-quiet anechoic chamber for 45 minutes – he debunked the myth that the lack of stimulation would send you mad, but did report a few odd sensations. 

“Perhaps the weirdest thing I noticed was the sense of my heart,” he says.

“I just felt like it was pumping really hard, and I could feel, almost like the blood pushing up through me. It wasn’t like I was hearing it, it was like I was feeling it. And I was feeling as though, in a way, my heart was shaking my body. That was something weird.”

In this situation, Derek didn’t exactly experience hallucinations, but what he describes with his heart does suggest his brain was amplifying things in the absence of any stimuli.

Interestingly, researchers demonstrated a similar effect in an experiment in 2015, where they asked volunteers to stare into each other’s eyes for 10 minutes straight.

“The participants in the eye-staring group said they’d had a compelling experience unlike anything they’d felt before,” Christian Jarrett reported for the British Psychological Society’s Research Digest at the time. 

It’s an imprecise science, to be sure, because every person’s brain responds differently to the weird things we throw at it (figuratively), but you could give the Scam Nation method a try and see what happens to you. Just, if the Supreme Being from Time Bandits gives you a hard time, don’t blame us, okay?

A version of this story was first published in April 2016.

 



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Cuban ‘Sonic Attack’ Survivors Have Structural Changes in Their Brains, Study Finds

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Starting in late 2016, a number of US government personnel stationed in Havana, Cuba started reporting something strange: they heard intensely loud sounds emanating from a single direction.

 

The source of those sounds is still a complete mystery to this day. Even stranger: the strange sounds seemed to make the staffers physically ill – with reported symptoms ranging from hearing loss and dizziness to intense headaches.

A new analysis published Tuesday in the journal JAMA found that the incident – often labelled as the “Cuban sonic attack” by the media – may have caused alterations in the victims’ brains.

The team of researchers found differing “neuroimaging findings” between control groups and those who were exposed to the attacks by examining brain scans using three different types of imaging techniques.

The findings include “significant differences” in white matter volumes among many patients, as well as lower functional connectivity in the auditory and visual parts of the brain.

The team, led by Ragini Verma, a PhD candidate at the Department of Radiology at the University of Pennsylvania, did note that the results have to be taken with a grain of salt and that the relevance of the differences “may require further study”.

One major caveat: the team did not have access to brain scans prior to being exposed to the phenomena as a point of comparison.

 

According to the BBC, the study was immediately panned by Cuban scientists. Cuban lead scientist Mitchell Valdés-Sosa told the BBC that “the changes in the brain images are very small, very diverse and very diffuse… They do not correspond to a coherent explanation.”

Scientists have been trying to figure out what’s behind “Havana syndrome” ever since the first reports started surfacing in August 2017.

According to a separate 2018 study, the diplomats experienced “moderate to severe sensorineural hearing loss” and “persistent sleep dysfunction” as a result of being exposed to “auditory and sensory phenomena.”

Yet no smoking gun was ever found. A media frenzy of conspiracy theories followed, with some theorizing that the event involved the use of a sonic or microwave weapon.

The Associated Press even obtained a recording of strange sounds the personnel were hearing, but it never ended up helping the investigation.

The embassy in Havana was only reopened in August 2015 after being shut for over 50 years – a major turning point in the relationship between the two countries.

But while the US has yet to publicly voice its own theory as to what went down, Cuba-US relations have taken a hit as a result of the alleged attacks.

This article was originally published by Futurism. Read the original article.

 



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A Boy Almost Lost His Hearing Thanks to a Parasite Burrowed Into His Eardrum

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To be fair, there is no part of your body you’d want to find a tick nestled in for a long liquid lunch.

But if there was any place you’d really consider out of bounds to a tiny bloodsucker, it’s your eardrum.

 

That’s exactly what doctors found when a 9-year-old boy from Connecticut reported a strange sound in his right ear. Yep, cue wincing.

There are two questions you really need to ask in a case like this. How did it get in there? And – far more importantly – how will it come out?

According to Darius Kohan, director of otology at Lenox Hill Hospital in New York City, the ear canal is a perfect place for just about any creepy-crawly to slip inside.

Kohan wasn’t part of the medical team responsible for treating the patient, but he does know a thing or two about ears and the objects they attract.

“We believe the wax in the ear attracts the bugs and they get stuck behind hairs into the wax, or – like in this case – penetrate the skin or eardrum,” Kohan told E.J. Mundell from HealthDay.

To a tick, the warm, moist conditions and protected shelter of an ear canal would be just the place to hide. Exactly how this one got so far inside is a mystery, but it was most likely picked up while the young patient was playing outdoors.

 

With no pain or loss of hearing, the only sign that something was amiss was a buzzing noise that persisted for several days.

On investigation, this is what the attending doctor saw. Try not to make any crying sounds.

tick eardrum eeek(Kohan etal/New England Journal of Medicine, 2019)

For those who aren’t familiar with the 900-odd species of tick on our planet, this one happens to be a prime example of an American dog tick, Dermacentor variabilis.

Common across the US, these tiny arachnids dig mouthparts called capitulum into the skin of their host to hold on tight while they slurp up a generous belly full of blood.

Most insects can be euthanised and flushed out with a good dose of warm mineral oil.

Not this guy. That capitulum anchors it in place, and any attempt to yank it out isn’t going to end nicely for either the tick or its host.

According to the two physicians reporting on the case, David Kasle and Erik Waldman, an initial attempt was made to simply pluck the tiny intruder from the eardrum.

 

“Removal of the tick with guidance from an operative microscope was attempted in the office, but the tick could not be removed,” says their report.

Thankfully they didn’t try all that hard. The membrane making up the eardrum is a delicate piece of biological machinery. Tearing it wouldn’t just cause the poor child immense pain, it would risk his hearing.

Unfortunately leaving it in there also wasn’t an option, risking infection and permanent damage to the eardrum.

To do a proper job of evicting the tick, the physicians brought out the big guns and prepped the young man for surgery.

“We took him to the operating room, put him to sleep, and we were able to use pretty fine utensils to remove the capitulum of the tick,” Kasle told CNN reporter Susan Scutti.

The tale has a happy ending for all but the plucky Dermacentor variabilis. The boy was fine, with a perfectly intact eardrum and no signs of fever or rashes. And the doctors had a cool story to tell their grandkids.

Maybe not as cool as the time doctors found a tick stuck a person’s eyeball. No, really, you don’t want to look.

Ok, if you must. Cue more wincing.

This research was published in the New England Journal of Medicine.

 



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This Strange Quirk in Your Brain Could Explain Why You Can ‘Hear’ Silent Gifs

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By now, you may have already seen some of the ‘noisy GIFs’ floating around the internet. They don’t actually contain any sounds, but plenty of people seem to nonetheless be able to ‘hear’ the noise produced in the image.

 

The skipping powerlines is definitely the most popular one we’ve seen, but you might also be able to hear SpongeBob flipping burgers, or this guy jumping off a bridge and splashing into water.

New research is showing that the reason why so many people can seemingly ‘hear’ these sounds could be due to differences in the way the visual and audio processing parts of the brain work together in some people.

“Our latest study reveals normally-occurring individual differences in how our senses of vision and hearing interact,” explains senior author and psychologist Elliot Freeman, from City University London.

“We found that people with ‘visual ears’ can use both senses together to see and also ‘hear’ silent motion, while for others hearing is inhibited when watching such visual sequences.”

GIFs don’t have sound. They are silent video loops, but some people can ‘hear’ corresponding sounds – like the thump of an electricity pole or a splash of a wave.

We’ve written about the science of these noisy GIFs and other perceived sounds before, but this new research – by the same team – is looking deeper into what causes this sensation, called ‘visual-evoked auditory response’ (vEAR).

 

“We found that as many as 21 percent of people may experience forms of this phenomenon, which makes it considerably more prevalent than other synaesthesias,” said Freeman back in 2018.

There are two popular hypotheses for why this might work. Either there are people who have extra connections between the visual and auditory processing areas of the brain, which causes vEAR; or everyone has the same connections, but only those with vEAR can use them.

The research team had just over 50 participants take part in a couple of experiments. They used a method called transcranial alternating current stimulation in two different wavelengths and measured people’s ‘hearing’ responses to Morse code sequences.

For those that didn’t experience vEAR, the stimulation currents did actually change the way their brains worked. If the stimulation was placed near the visual processing areas of the brain, the non-VEAR participants experienced reduced visual performance but improved audio performance.

This was vice-versa for when the stimulation was placed near the auditory processing parts of the brain.

Meanwhile, for those who did experience vEAR, there was no change.

 

Interestingly, the 50 participants included 16 musicians from the London Royal College of Music, and they were significantly more likely to report experiencing vEAR than non-musicians.

“We were also interested to find that, on average, participants with visual ear performed better on both visual and auditory tasks than those without. Perhaps their audio-visual cooperation benefits performance because more of the brain is engaged in processing visual stimuli,” explains Freeman.

“Such cooperation might also benefit musical performance, explaining why so many of the musicians we tested reported experiencing visual ear.”

This study was pretty small, so the researchers will have to investigate further with a bigger group of people, but even so, it’s an interesting look into a super-weird phenomenon.

You can see more ‘noisy’ GIFs on this subreddit, and the study has been published in the Journal of Cognitive Neuroscience.

 





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