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Scientists suggest invisibility as a cure for anxiety

Neuroscientists have made the surprise discovery that the sensation of invisibly reduces responses to anxiety.

Have you ever felt fear and anxiety from standing in front of a large audience and giving a speech? Or how about having to get up in class and talk to other students? While it's normal in situations like these to wish for the ground to swallow you up, some scientists have suggested a slightly different remedy for anxiety - invisibility.

Invisibility has long featured in myths and fiction, but several advances in material sciences have demonstrated that the cloaking of large (living) objects - just like how the invisibility cloak works in Harry Potter - is becoming a realistic prospect. In the field of material sciences, the general concept of invisibility cloaking is actually fairly simple.

Theoretically, all that's needed is a material that guides visible light (or another wave, like EM waves or heat fluxaround an object, and anything within the gap it leaves will be rendered "invisible" to someone standing at the light source:

Light moves around the object (or person) as though it isn't there. Image: Trevor Johnston/trevorjohnston.com

In practice, this is hard to achieve, as most naturally occurring materials reflect light, cast shadows and produce a reflection. However, hi-tech and exotic materials called "metamaterials" have made light bending possible. (Although latest research suggest that ordinary lenses can do just the trick!)

H G Wells, a man ahead of his time, wrote the The Invisible Man in 1897. The novel is about a protagonist who invents a method to change the human body’s refractory index to that of the air, rendering it invisible. (The twist comes when he performs the method on himself and can’t reverse it - but that’s beside the point.) The refractive index is the ratio between how light passes through a vacuum, and how it passes through any other medium; it’s the reason a spoon will look bent when placed in a glass of water. If water has a negative refractive index, the spoon would look as though as was bending back on itself instead.

In a recent paper in Scientific Reports, graduate students Arvid Guterstam and Zakaryah Abdulkarim and their advisor Henrik Ehrsson, a neuroscience professor at the Karolinska Institutet in Stockholm, said they believe invisibility cloaking of the human body is a thing of the future, and believe it’s high time we delve into what it feels like to be invisible.

To do this, Guterstam, Abdulkarim, and Ehrsson used virtual reality. In one of their experiments, 23 people were provided with a set of head-mounted displays (HMD), and were asked to look at their feet. The experimenter - Abdulkarim - stroked their arms, legs, and torso with a paintbrush with one hand, and at the same time, made identical motions with a second paintbrush with the other hand, on an invisible body or a mannequin. A pair of downward-facing cameras that were either mounted on a tripod or on the head of a mannequin sent a real-time video feed to the participants HMDs, giving them the sensation of being invisible, or making a body swap with a mannequin:

Study co-author Zakaryah Abdulkarim (middle) creates the invisible body illusion on a participant (left) wearing a set of head-mounted displays connected to a pair of cameras. Photo: Staffan Larsson

Here's the surprise: after finishing with the paintbrush, each participant slowly lifted their gaze through their HMDs to find that they were being watched by a scornful-looking audience (consisting of 11 scientists instructed to stare at the participant). Quite creepy, and perhaps enough to through most people off - however, on a 100-point scale, participants reported their stress level as about 25 per cent lower, on average, when in a state of invisibility, and about a third less than in the mannequin version. The state of invisibility also lowered heart rates by a few beats per minute, suggesting that stress is intertwined with physiology.

The researchers write: “Our results demonstrate that healthy individuals can experience the illusion of owning an invisible full body." They suggest their results could spur on better a design for virtual-reality based therapies for social anxiety, and may also help give neuroscientists gain new insight into phantom limb illusions.

Tosin Thompson writes about science and was the New Statesman's 2015 Wellcome Trust Scholar. 

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An antibiotic-resistant superbug is silently spreading through UK hospitals

There have already been outbreaks in Manchester, London, Edinburgh, and Birmingham, but deaths are not centrally recorded. 

Lying in a hospital bed, four months pregnant, Emily Morris felt only terror. She had caught a urinary tract infection and it was resistant to common antibiotics. Doctors needed to treat it as it could harm the baby, but the only drugs that could work hadn’t been tested on pregnant women before; the risks were unknown. Overwhelmed, Emily and her husband were asked to make a decision. A few hours later, gripping each other’s arms, they decided she should be given the drugs.

In Emily’s case, the medicine worked and her son Emerson (pictured below with Emily) was born healthy. But rising antibiotic resistance means people are now suffering infections for which there is no cure. Doctors have long warned that decades of reliance on these drugs will lead to a "post-antibiotic era"– a return to time where a scratch could kill and common operations are too risky.

It sounds like hyperbole – but this is already a reality in the UK. In the last four years 25 patients have suffered infections immune to all the antibiotics Public Health England tests for in its central lab, the Bureau of Investigative Journalism has discovered.

While these cases are rare, reports of a highly resistant superbug are rising, and infection control doctors are worried. Carbapenem resistant enterobacteriaceae (CRE) are not only difficult to pronounce, but deadly. These are bugs that live in the human gut but can cause an infection if they get into the wrong place, like the urinary tract or a wound. They have evolved to become immune to most classes of antibiotics – so if someone does become infected, there are only a few drugs that will still work. If CRE bacteria get into the bloodstream, studies show between 40 per cent and 50 per cent of people die.

These bugs are causing huge problems in India, certain parts of Asia, the Middle East and some countries in southern Europe. Until recently, most infections were seen in people who had travelled abroad, had family members who had, or had been in a foreign hospital. The boom in cheap cosmetic surgery in India was blamed for a spate of infections in Britain.

Now, doctors are finding people who have never boarded a plane are carrying the bug. There have already been outbreaks in Manchester, London, Liverpool, Leeds, Edinburgh, Birmingham, Nottingham, Belfast, Dublin and Limerick among other areas. Patients found with CRE have to be treated in side rooms in hospital so the bacteria does not spread and harm other vulnerable patients. But in many of Britain’s Victorian-built hospitals, single rooms are in sparse supply. Deaths from CRE aren’t centrally recorded by the government - but it is thought hundreds have already died. 

Across the country, doctors are being forced to reach for older, more toxic drugs to treat these infections. The amount of colistin – called the "last hope" antibiotic as it is one of few options still effective against CRE infections - rose dramatically in English hospitals between 2014 and 2015, the Bureau has revealed. Colistin was taken off the shelves soon after it was introduced, as it can harm the kidneys and nervous system in high doses, but was reintroduced when infections became immune to standard treatment. The more we use colistin the more bacteria develop resistance to it. It’s only a matter of time before it stops working too, leaving doctors’ arsenal near-empty when it comes to the most dangerous superbug infections.

Due to a kidney problem, Emily Morris suffers repeat urinary tract infections and has to be hospitalised most months. Her son Emerson comes to visit her, understanding his mummy is ill. If she catches a superbug infection, she can still be given intravenous antibiotics to stem it. But she worries about her son. By the time he is an adult, if he gets ill, there may be no drugs left that work.

Madlen Davies is a health and science reporter for the Bureau of Investigative Journalism