Seeing red: why do we blush?

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Evolution / Health / Myths / Psychology

Do you blush easily? Many of us blush when we feel embarrassed, ashamed, or nervous, generally when we least want to be noticed. It might happen when you meet someone new, receive a compliment or have to speak in front of a group. Why do our cheeks go red, and why can’t we control it? And do our red cheeks serve any purpose?

Why do we blush? Why do some of us blush more than others? And could blushing actually be useful? Image credit rebecca pedro via Flickr

Why do we blush? Why do some of us blush more than others? And could blushing actually be useful? Image credit rebecca pedro via Flickr

The puzzle of blushing

Back in 1872, Charles Darwin wrote a whole chapter about blushing and concluded:

Blushing is the most peculiar and most human of all expressions. Charles Darwin, The Expression of Emotion in Man and Animals 

Darwin wrote letters to colony administrators and missionaries all over the world to find out the answer to one simple question: do all humans blush? The answer is yes, people of all ethnicities blush, although blushing is less visible on darker skin. Fascinatingly, blushing is one of the things that sets us apart from other animals: unlike most expressions, no equivalent has been found in any animal. It’s not that we can’t see an animal blushing under its fur or feathers; animals just don’t blush.

On the one hand, the process of the skin on our faces turning crimson isn’t terribly complicated. The muscles in the walls of your veins relax and allow more blood to flow. Blood flow to your skin is controlled by the sympathetic nervous system (the part of your nervous system responsible for the fight or flight response). When this part of your nervous system is activated, the hormone adrenaline is released into your system. Adrenaline acts as a stimulant. Your heart rate goes up, your pupils dilate so you can take in as much visual information as possible. Your blood vessels dilate to improve blood flow and maximise the delivery of oxygen to your muscles. You’re all ready to put up a good fight or get the hell out of there.

I’m so embarrassed

But sometimes, the veins in your face also respond to the adrenaline, dilating and letting more blood flow through them than usual. This increased blood flow is responsible for the spreading crimson and warmth we call blushing and we have no conscious control over it. You can’t blush on command and neither can you stop blushing when you want to. The interesting thing is veins don’t normally respond to adrenaline: in other parts of your body, your veins don’t do much in the presence of adrenaline. There are other times when your cheeks may become flushed: after a couple of drinks at the pub or when you’re exercising, but these are different to what we call blushing.

So why do our cheeks go bright red? We don’t know for sure, but we do know there are specific triggers for blushing: we blush when we’re feeling embarrassed, ashamed or exposed. Blushing occurs when we are receiving unwanted social attention. It seems cruel that at the exact moment we wish the floor would swallow us up because we’re so embarrassed, our cheeks turn flame-red, drawing even more attention to ourselves. Fear of blushing (erythrophobia) is a recognised social phobia and causes enormous distress to sufferers. Research has shown people who fear blushing believe they will be judged negatively for blushing. Feeling anxious about being judged means blushing can become a self-fulfilling prophecy. Even being told we are blushing when we’re not can cause many of us to actually blush.

When blushing is a problem

Chronic blushing – when a person blushes more often and more obviously than most of us – is also a debilitating condition. About 5% of the population suffer from it and a quick read of an online support page reveals stories of sufferers feeling unable to leave the house. Chronic blushers blush in normal social situations that wouldn’t usually result in blushing, for example, in response to someone saying their name. There are a few different treatment options for chronic blushers: some sufferers use corrective make-up, others have success with medication, others find relief with cognitive behavioural therapy or hypnotherapy.

A more controversial response is surgery. Bilateral Endoscopic Thoracic Sympathectomy involves cutting the nerves responsible for blushing. These are the nerves that cause the veins in the face to dilate and are usually cut under the armpit. This surgery has mixed reviews: while many patients report it solves their blushing problem, some are unhappy. Because the nerves involved with blushing are also involved in sweating, some patients end up with a different, but equally unsettling problem. Post-surgery, patients are unable to sweat from the face, which can lead to excessive sweating in other parts of the body.

The benefits of blushing

All of this begs the question: why have we evolved to blush? Can there be any benefit to that hot glow of embarrassment most of us have experienced? Research suggests the answer is a definite yes. One study demonstrated we are more likely to trust people who are easily embarrassed. For example, we are far more likely to trust and want to hang out with someone who shows embarrassment rather than pride at being told they’ve done well on a test.

And what of blushing itself? A number of studies point to the fact blushing may have evolved as a way of signaling regret or remorse. Blushing signals we know we’ve done something wrong and we’re sorry. It’s reliable evidence of the fact we genuinely feel bad about having done something wrong because it can’t be faked. Because it’s out of your control, blushing is much more reliable than a verbal ‘sorry’. We trust and forgive people who blush more than those who don’t: a number of researchers believe blushing is an important part of the social glue that keeps human societies functioning.

So next time you feel that familiar warm glow of discomfort, try to remember there is an upside. You’re telling the world you can be trusted.

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Can animals count?

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History / Mathematics / Myths / Zoology

We’ve all heard about ‘clever’ animals. Chimpanzees, elephants, dolphins… there are plenty of examples of animals learning to use tools, communicate complex information and solve problems. But how about maths: can animals count?

A horse is a horse, of course, of course, that is of course unless the horse is the famous Clever Hans! Image: public domain

A horse is a horse, of course, of course, that is of course unless the horse is the famous Clever Hans! Image: public domain.

Clever Hans and Alex the African Parrot

Clever Hans, an Arabian stallion, was famous for his ability to count. Beginning in 1891, retired high school maths teacher William van Osten wowed European crowds with shows of Hans’ extraordinary abilities. When asked what two plus three equaled, Hans had no trouble giving the correct answer by the number of times he tapped his hoof. Many scientists observed Hans answering maths questions and couldn’t find any evidence of fraud or trickery. It wasn’t until 1907 that the truth was uncovered. Hans’ brilliance didn’t lie with his sums, but rather with his incredible ability to read human body language. Even his trainer wasn’t aware Hans would simply tap until tiny changes in the facial expressions or other body language of his observers indicated he had reached the correct number of taps. When his observers relaxed, Hans stopped tapping.

Unlike Clever Hans, Alex the African Grey Parrot appeared to have genuine mathematical ability. When he died aged 31, Alex could count up to eight and perform a variety of sums. For example, he could tell you that two plus one plus two jellybeans made five. Alex also had a vocabulary of more than 100 English words, which he could use correctly. No, he wasn’t just parroting them. Alex’s trainer says he also had an understanding of zero, which is more impressive than it might sound. Alex’s maths was on par with chimpanzees and other non-human primates and his abilities have been the focus of dozens of scientific papers.

Maths and mammals

It’s not surprising primates have been found to be top maths students in the animal world. Since the 1980s, many researchers have demonstrated the capacity of primates, particularly chimpanzees and rhesus monkeys, to do maths at a similar level to very young kids. This means not only being able to do basic adding up, but also understanding what zero is. Chimpanzees have no trouble learning to match an empty food tray with ‘zero’. Monkeys are also able to match the number of sounds they hear with the right number of objects. More recent research has focused on understanding what is actually going on inside a monkey’s head while doing sums.

What about other mammals; is it only primates who can learn maths? Not at all. Brutus the black bear can discriminate between larger and smaller numbers and dogs can count up to four or five. Like monkeys, elephants can rank small numbers in order and compare the answers of very simple sums. When lions hear the roars of other lions intruding into their territory, they decide to attack only if they outnumber them. Similarly, hyenas can tell the difference between one, two, or three intruders on the basis of calls. And if you’re concerned Clever Hans tarnished the mathematical reputation of all horses, don’t worry. We now know horses really can tell the difference between small numbers.

Counting crows

In the bird world, having some basic maths smarts isn’t limited to Alex the parrot. We’ve known for a long time crows are brainy: they use tools and solve problems. Crows can also learn to count – tell the difference between different numbers of dots. What’s more, researchers have worked out which brain cells are involved in the process. New Zealand robins watch researchers hide tasty beetle larvae in holes in logs and then immediately go to the hole where the largest number of larvae were stashed. If the scientists removed some of the larvae when the robins weren’t looking, the birds got agitated and kept searching: they knew they’d been tricked.

Newborn chicks, without any training, can tell the difference between a small number, and larger number of balls. American coots appear to count the number of eggs in their nest, as well as in the nest of birds around them. Even the humble pigeon can tell the difference between many (six or seven) and few (one or two) dots. In fact, in some maths tasks (like ranking numbers from smallest to largest), pigeons are just as good as monkeys.

Ants on stilts

There’s plenty of evidence you don’t even need a backbone to be able to count: invertebrates can do it too. Honeybees can count up to four objects they encounter while out searching for food. Ingenious experiments making use of tiny stilts showed that desert ants use a perception of number steps to find their way back home to their nest after searching for food. The researchers suggest the ants have something acting like a pedometer in their brains. Recent research showed that cuttlefish can accurately tell the difference between different numbers of tasty shrimp, up to the count of five.

Animals may not be doing long division but in many cases, they can count, or at least tell the difference between bigger and smaller numbers. We shouldn’t be surprised: whether an animal is searching for food, or working out how many enemies are invading, being able to tell the difference between more and less makes a lot of sense.

And hey, even plants can count. Venus flytraps decide whether to snap shut their traps and start producing a cocktail of enzymes to digest their prey on the basis of how many times their trigger hairs get touched. No point wasting energy on a false alarm.

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Just doodle it!

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Health / History / Myths / Psychology

Do you doodle? Sketch? Or like many people, were you told at some point you were bad at drawing and gave it up completely? While virtually all kids draw, few adults do. But there’s good evidence we should all pull out our coloured pencils: drawing and doodling improve focus and memory and can help us learn.

Do you doodle? Your ‘mindless’ scribbles could actually be helping your brain stay focused, process thoughts and retain Information. Image credit: Loes van Voorthuijsen via Flickr

Are you a doodler? Your ‘mindless’ scribbles could actually be helping your brain stay focused, process thoughts and retain information. Image credit: Loes van Voorthuijsen via Flickr

Is drawing a thing of the past?

In days gone by, drawing was an important and valued skill in a variety of jobs. Before cameras, printers, scanners and Flickr, if you wanted a picture of something, you drew it. And humans have been drawing for a long time: the oldest drawings we have found so far are on cave walls on the Indonesian Island of Sulawesi. They date back more than 35,000 years.

In our own lives, drawing tends to be a big part of childhood but then peters out. Kids start scribbling at about two and from around the age of four, begin to draw shapes. By the age of seven, kids are accurately portraying the people, animals and scenes around them: kids in detention centres often draw fences and barbed wire. But by the age of nine or ten, many kids become critical of their drawings and declare ‘I’m no good at drawing’. When they discover they don’t have the skills to draw their reality accurately, many give up. There have been recent calls for drawing to be brought back into school curricula. The argument is that drawing is a learned skill and more of us would continue to draw if we were taught how to do it better.

Doodling is a long way from being a bad habit

Of course some adults do continue to draw. But often we draw during meetings, on the margins of the agenda papers. We try to hide the fact we’re drawing because we’re worried about the impression it creates. The thing is, we tend to think someone who’s doodling is not doing what they are supposed to be doing: that is, listening. Even the word doodle carries negative connotations. In the 18th century, to doodle meant to swindle or ridicule someone. A century later, a doodle was a corrupt politician.

The irony is we now know just how wrong many assumptions about doodling are. Doodles aren’t meaningless marks and doodling isn’t a waste of time. I’ve written before about the calming benefits of the colouring-in craze. And many people find doodling to be enjoyable and relaxing. But doodling is also a powerful way to improve listening, thinking, focus and concentration. We rarely set out to doodle; doodling is just what happens when our brains are processing information. There are a number of well-known instances of U.S Presidents doodling while making decisions.

One of the first studies that aimed to test whether doodling improves concentration asked people to listen to a monotonous telephone message. Their job was to listen out for the names of people coming to a party amongst lots of irrelevant information. Half of the listeners were asked to doodle: shade printed shapes while listening to the call. The rest had to listen without anything else to do. When they were given a surprise memory test, the doodlers remembered a third more names than those who had concentrated only on the message. The researchers believe doodling prevented the listeners from daydreaming and getting distracted.

Drawing to remember

Forget surprise memory tests: if you know you need to remember something, try drawing it. In one study, 14-year olds were given 850 words to read about the biology of flu. It was a hard read, and the students knew they were going to be tested on what they had learned. Importantly, half the students were asked to make a drawing to represent each of the seven paragraphs. The remainder simply read the text. When they were later tested on how much of the science they had understood and remembered, the drawers did way better. In a second experiment the same was true even when the reading-only group was given the text with drawings already provided. It was the act of drawing their own pictures that resulted in those students remembering what they had read. It seems science is now demonstrating what artists have known for a long time.

“When you draw an object, the mind becomes deeply, intensely attentive. And it’s that act of attention that allows you to really grasp something, to become fully conscious of it.”                 Designer Milton Glaser

In another series of experiments, researchers tested whether it was easier to memorise a series of words by writing or drawing. University students were given a list of easily-drawn words like ‘apple’. For each word, they students had 40 seconds to either draw the object, or write the word repeatedly. Later the students were given a minute to remember as many of the words as they could. The drawing students remembered twice as many words as the writing ones. Again, looking at pictures drawn by someone else didn’t have the same effect. Even when the students were only given four seconds for their drawings, these students had a huge advantage in later memory: the quality of the drawing didn’t matter.

So it doesn’t matter whether we think we’re any good at it or not. The time has come for us all to get doodling.

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Breaking bad… habits

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Health / Myths / Psychology

Got any bad habits? Smoking, biting your nails, compulsively checking your email or heading to the vending machine every day at 3pm? We’ve all got habits we’d like to break. Perhaps there are a few new habits you’d like to adopt too. What can science tell us about how to do it?

Breaking habits can be hard, so why not tackle them all at once? Image credit: Vaping#60.com via Flickr

Breaking habits can be hard, so why not tackle them all at once? Image credit: Vaping360 via Flickr

Your brain on autopilot

Ever arrived somewhere in your car and realised you have no memory of having driven there? Do you remember putting on your shoes this morning, or brushing your teeth? Probably not. There are plenty of times during the day that we act on autopilot. And this is precisely why habits are hard to break: we find ourselves doing the very thing we want to stop doing before we’ve even noticed we’re doing it. Habits are unbelievably powerful and account for about 40% of our behaviours on any given day.

Habits are deeply ingrained in our brains and changing them can prove extremely difficult. Rats that have been trained to seek out chocolate milk continue to do so even after a chemical is added to the milk that causes nausea. People who like to eat popcorn at the movies eat just as much even if it’s horribly stale. Breaking one habit means establishing a new one and despite many people claiming you can form a new habit in 21 days, a 2009 study found for some people it took more than 200 days.

Baby steps

The conventional wisdom on how to change habits is to take a gentle approach. If you want to lose your sweet tooth, cut back on sugar gradually rather than going cold turkey. Another popular recommendation is to tackle one habit at a time. The argument is that if you start small – exceedingly small – long-term change becomes far easier to achieve. Makes sense, right?

Except that maybe we are underestimating our capacity for change. Research published earlier this year suggests we may be up for a way bigger challenge. The researchers put a group of university students to the test. Before the experiment began, they gave the students a series of mental and physical tests, and scanned their brains. The students were split into two groups, one of which went about their daily lives.

The other group made major changes to many different parts of their lives. Every morning they spent an hour in a stretching, resistance training and balance class. Next they spent an hour learning meditation and other stress reduction techniques. In the afternoon they spent another hour and a half exercising and twice a week they did intense interval workouts. They also went to lectures about nutrition and sleep and kept daily records of their moods, diet and sleep patterns.

Does a major overhaul work?

After six weeks, the researchers asked the students to repeat the original tests. Unsurprisingly, there hadn’t been any change for the students who continued with their normal habits. But the group who overhauled their lives were happier, calmer, fitter, stronger, more flexible and improved their test results for thinking and memory. Their brain scans suggested these students were now much better able to focus on any particular task at hand. Six weeks later and the improvements were still there even though the students weren’t exercising or meditating as often.

This study has obvious flaws. For a start it only included a small number of people. And those of us with commitments like jobs and families are unlikely to be in a position to make such major changes to how we spend our time. They also didn’t have a group of people who changed just one daily habit to compare with. But the fact remains that with support and guidance, these students made concurrent and major changes to many of their daily habits.

The limits of the human capacity for change may be much greater than we, as scientists, have given people credit for.

Michael Mrazek, University of California

Despite its shortcomings, I think the study has something interesting to say. Under the right circumstances we may be far more adaptable than we give ourselves credit for. Rather than trying to make small and incremental changes, it may be that the best way to change bad habits is to unceremoniously dump them all at once.

Habits be gone

But if trying to change everything at once doesn’t appeal, there are a number of other strategies you can try. There are still plenty of people advocating for the “start so small you can’t fail” approach. Other people like the Pavlok (yes, it was named after Pavlov of drooling dog fame), a device you wear on your wrist to give yourself a painful electric shock every time you slip back into old habits.

There’s also evidence that simply walking a different route to work may be enough to break your habit of stopping by the bakery for a bagel every morning. You just have to interrupt your autopilot. And of course like everything else these days, there are apps to help you keep track of your habits.

Some of the most striking evidence for habit change comes from mindfulness research. When it comes to quitting smoking, mindfulness training was twice as good as other quit programs. Mindfulness can also help with emotional eating, checking your phone while driving and other addictive behaviours. The key is to notice your compulsion to do certain things and become curious about what’s going on in your body and mind at the time.

I’ll take being curious and aware over an electric shock any day.

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Gotta spot ’em all!

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Ecology / Myths / Psychology / Zoology

Can’t get enough of Pokémon Go? There’s no shortage of people glued to their screens desperate to catch a Snorlax or Vaporeon. At the same time, thousands of people are hooked on Wildlife Spotter: a National Science Week project that involves spotting real animals. Why is the search for these real and imaginary creatures so addictive?

Thousands of citizen scientists are identifying animals from millions of iamges taken by automated cameras across Australia. But why is it so addictive? Image credit: Stebbing via Flickr

Thousands of citizen scientists are identifying animals from millions of images taken by automated cameras across Australia. But why is it so addictive? Image credit: Stebbing via Flickr

When you don’t know what you’re going to get

Back in the 1950s, psychologist B. F. Skinner made a fascinating discovery. Inside a Skinner Box, lab rats had learned to press a lever to get food. Rats that received the same amount of food each time they pressed the lever pressed it regularly in order to get their treat. But in a different experiment, things became less predictable for the rats. Despite pressing the same lever in the same way, sometimes the rats got a tiny treat and other times they got a big one. At other times, the rats got nothing at all. You might think these rats would get frustrated and give up. Quite the opposite: rats that couldn’t predict what treat they were going to get ended up pressing the lever obsessively.

Research ever since has shown rewards that are unpredictable, or variable, affect us profoundly. It’s the times we don’t know what we’re going to get that we seek out a reward most compulsively. If you think I’m talking about playing the pokies, that’s a good example. No one can never predict when, or how much they’re going to win. But someone wins just often enough to keep everyone coming back for more.

An unexpected reward has much more power in driving behavior than one that is regular. This has been known for a very long time.

– Nora Volkow, Head of the U.S. National Institute on Drug Abuse.

Dopamine made me do it

Even if you’ve never put a coin in a slot machine, I’m guessing you’ve still experienced the power of variable rewards. Ever found yourself compulsively checking your email? Facebook? Twitter? It’s the same deal. Every time you refresh your inbox, there’s a chance you’ll find a new and exciting email. Every time you check, it’s possible someone – or lots of people – will have liked or commented on something you posted. But it’s very hard to predict which of your photos, posts or tweets will be the popular ones. You just never know. And that’s what keeps you checking again and again.

Our reward-seeking behaviour is driven largely by the chemical messenger dopamine. Dopamine has lots of functions in our brains, including playing a role in our perception of rewards. When we get a reward, dopamine systems in our brains are activated and as a result, dopamine motivates us to seek out more rewards. Dopamine is released in our brains in response to lots of pleasurable things like social contact, eating food and listening to music. Explaining our love of social media, research has shown that our dopamine system also activates when we share information about ourselves. Self-affirmation also appears to activate our brain’s reward pathways. Dopamine leads us to anticipate rewards and is particularly stimulated by the unpredictable rewards we’ve just been talking about.

Wildlife Spotter

What does all this have to do with spotting wildlife? I’ll explain shortly.

Wildlife Spotter is the ABC’s National Science Week Citizen Science Project for 2016. It asks the public to help scientists in their efforts to conserve Australia’s precious native animals. One of the exciting ways wildlife researchers can work out where particular animals occur is using camera traps. These are remotely-triggered cameras that are motion sensitive. So when an animal moves, the camera snaps a photo of it, day or night. Camera traps allow scientists to keep an eye on their research sites 24-hours a day for months, or even year at a time. This is particularly beneficial in a country the size of Australia where much of the wildlife we want to monitor lives in remote areas.

There are two downsides to this otherwise brilliant technology. One: the cameras are very sensitive, so even leaves swaying in a breeze can prompt the camera to snap an image. This means plenty of camera trap images don’t have any animals in them at all. Two: partly as a result of downside one, and also because of the long periods of time camera traps can operate, researchers end up with enormous numbers of camera trap images they need to look at.

This is where citizen scientists come in: members of the public who are keen to volunteer their time to assist scientists from around Australia who have contributed their camera trap images to Wildlife Spotter. Since Wildlife Spotter was launched just over two weeks ago, around 26,000 people have identified nearly 700,000 animals in 570,000 photos. These are some extremely impressive numbers.

Spotting ’em all

Why has Wildlife Spotter captivated so many people? I think it’s because of the random nature of the reward. Camera traps give us a fascinating insight into a world we would otherwise never get to see: what animals do when we’re not around. But you never know what you’re going to get. With each new image that appears on your screen you may see a common animal like an emu or wombat. Or you may get to spot a rare and threatened animal like a bettong, malleefowl or bandicoot. But you may also see nothing more than some trees and grass. You just never know. And that’s what keeps you looking at a new photo again and again.

So if you’re a keen Pokémon Go player, how about switching your allegiance for a few hours (or days) and using your keen spotting skills to help conserve Australia’s wildlife? You might just find it even more rewarding.

 

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Remembering what never happened

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Health / Myths / Psychology

Do you often forget things? Wish you had a better memory? Me too. But there’s a far more sinister way your memory may be failing you. Being positive you remember an event is no guarantee it ever happened.

Could your memory be fooled into believing you had taken a ride on this balloon, just from the photograph? Balloon image credit Jayson via Flickr

Could you be fooled into believing you had taken a ride on this balloon? Balloon image credit Jayson via Flickr

Your memory is fickle

It’s tempting to think our memories work like video recorders: faithfully recording our surroundings, thoughts and feelings. We can accept our brains might not have room for everything, so we only end up holding onto the most important, (or traumatic, or embarrassing) bits. But do our brains construct entirely made-up memories? Sometimes, yes.

It’s not surprising our recollections of past events can be hazy and that we get small details wrong. For example, seven weeks after the event itself, a researcher asked people about their memories of September 11, 2001. Among other questions, was “on September 11th, did you see the videotape on television of the first plane striking the first tower?” Three-quarters were confident they remembered watching the footage on that day. Seems reasonable, except that the footage wasn’t actually aired until a day later. A tiny detail, but a good illustration of the way we misremember events.

Research has shown we constantly fill in the gaps between real pieces of memory, and along the way we make assumptions, and plenty of mistakes. We construct our memories, without even being aware we’re doing it. Emotional memories may be more accurate, but no memories are immune to contamination. Memories that are not quite right might lead to arguments with our loved ones, and probably won’t serve us well at trivia night. But at least our memories always vaguely resemble the truth. Right? Wrong!

The question isn’t whether our memories are false, it’s how false are our memories. Dr Julia Shaw, psychologist.

How was your balloon ride?

Far more unsettling than misremembering some aspects of a real-life event is remembering an event that never took place. Researchers now know exactly how to implant a false memory. It turns out to be an easy-to-follow recipe, particularly successful when applied to people who are ‘prone to suggestion’. What sort of false memories can you implant? Unsurprisingly, it’s easy to lead people to recall small, made-up details about a real event they witnessed. Hey, most of us have trouble recalling the small details of our lives anyway.

But under the right circumstances, you can lead people to create wholly fake memories. Psychologists showed people doctored photos of themselves in a hot air balloon. They followed up with guided imagery and voila: half of the study participants had memories of the completely fictitious balloon ride. Researchers also successfully got people to remember they had accidently spilled a bowl of punch on the parents of the bride at a wedding reception, despite the fact it never happened.

Participants in another study were asked to recall as many details as they could about childhood events – one that was entirely made up, involving being lost at the shops. About 30 percent of the study participants later recalled being lost, some creating specific details about a kind adult who had helped them. Recollections of the fake event were less detailed than those of real events but nonetheless, these people were convinced the event had happened.

Did you commit the crime? (Are you sure?)

Can you imagine ever confessing to a crime you didn’t commit? Seems unlikely, but research has shown how easily it can happen. In one experiment, people were falsely accused of making a computer crash by pressing the wrong key during a study supposedly about reaction times. All of those accused were completely innocent. Initially, all denied the charge. But after a witness admitted to having seen it happen, many signed a confession, felt guilty and went on to form their own memories of the ‘crime’.

In another study, seventy per cent of people became convinced that as teenagers, they had committed an assault with a weapon, which led to an encounter with the police. Half of these recounted specifics of their dealings with the police. A little bit of suggestion from someone with authority goes a long way.

And of course, witnesses aren’t immune to false memories. In a series of experiments back in the 1970s, students were shown images depicting an accident between a car and pedestrian. These students were then exposed to further information about the accident: either true (the car had been at a stop sign), or misleading (the car had been at a give way sign). The results showed witnesses integrated this additional information into their memory of the event. Those who had been given the suggestion tended to claim they’d seen a give way sign.

Given how powerful confessions are, what does all this mean for our legal system? Plenty. In particular, that the questioning of suspects (and witnesses) must be done very, very carefully.

Will the real memory please raise its hand?

How can you tell the difference between real and false memories? With great difficulty. Because once they’ve taken hold in your brain, false memories and real memories are pretty much indistinguishable. Corroboration is your best bet so if you want to be sure something really happened, you need reliable witnesses to validate your memories for you.

A good reason to make sure you’ve got at least one friend with an excellent memory.

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The sense of claustrophobia

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Evolution / Health / Myths / Psychology

Your panic is rising. The walls are closing in. You’re sweating, trembling, having trouble breathing and on the verge of fainting. It’s claustrophobia and it’s all-consuming. Many people experience claustrophobia and it can be utterly debilitating. Why, and what can be done?

Claustrophobia: like the walls are closing in... arrrgh! Image credit Catalina Olavarria via Flickr

Claustrophobia: like the walls are closing in… arrrgh! Image credit Catalina Olavarria via Flickr

When the ceiling is too close

Last week, I had an MRI. And for the first time, I had an inkling of what claustrophobia must feel like. I couldn’t see out either end of the MRI tunnel, and the ceiling did feel remarkably close to my face. Curiosity, rather than anxiety, filled my mind. But it wasn’t hard to imagine being engulfed by panic in that situation.

The word claustrophobia comes from the Latin, meaning fear of being shut in a place. Some of the most common places people experience claustrophobia are tunnels, cupboards, lifts, aeroplanes and MRI machines. Around 5% of the world’s population is thought to experience claustrophobia and women are more likely to suffer than men.  The severity of symptoms vary: in extreme cases a person may choose to walk dozens of flights of stairs rather than take a lift, avoid tunnels at all costs, or refuse to get into an underground train for decades.

Get outta my space

Why do only some people experience claustrophobia when few of us would claim to like feeling trapped? There are a few different theories as to what causes it. Of course, in many cases, claustrophobia is the result of a traumatic experience like being stuck in a lift – or an MRI machine. It’s hardly surprising that after being trapped somewhere we feel anxious about going back into that place. But research suggests some people are also predisposed to feeling claustrophobic.

One study found people with panic disorders have a smaller amygdala than average. Your amygdalae – there are two in your brain and they’re shaped like almonds – process emotions like fear. Perhaps someone with smaller amygdalae perceives the risk of danger differently and these are the people more likely to experience claustrophobia. A few years ago, other researchers announced they’d found that a mistake in a single gene causes claustrophobia symptoms in mice. Humans have the same gene, found in an area of a chromosome linked to panic disorders. If a defect in this gene can also explain claustrophobia in people, the fact is some of us simply have claustrophobia in our genes.

A fascinating study connected people’s perception of their personal space to their experience of claustrophobia. We all have a perception of how far our personal space extends beyond our body – interestingly this distance is related to arm length. This personal space is our comfort zone, and we are very aware of anything entering it. But people who experience claustrophobic fear tend to feel their personal space extends further than we would predict. For these people, the larger space means there are more frequent intrusions into that personal space. They are more likely to feel like someone or something is ‘in their face’.

Claustrophobia makes sense

There are a variety of treatments for claustrophobia. Virtual reality has been successfully used to reduce fear of confined spaces and cognitive behavioural therapy has also helped many claustrophobes. There’s no lack of internet sites claiming to have the answer to solving claustrophobia. Some claustrophobes find that being forced to face their fears head on, for example, by being trapped in a lift is actually a good thing. Although terrifying at the time, people find their panic eventually disappears.

I completely understand that claustrophobia sufferers are desperate to find a cure for their fears. But it’s worth considering why we experience claustrophobia. If you think about it from an evolutionary point of view, claustrophobia makes very good sense. Of course we’ve evolved to be fearful of being trapped in a confined space. Throughout our past, and still today, many of the situations that result in us feeling trapped are life-threatening. Whether a collapsed cave, or collapsed building, we have every reason to fear for our lives. It’s to be expected that we’ve evolved to hate the feeling of being confined: claustrophobia makes complete sense.

The problem comes when a completely non-life-threatening situation evokes the same paralysing fear. I feel fortunate to be someone who can endure an MRI without panic. Although it did mean I got to focus all my attention on the terrible musac blaring through the headphones I was told to wear. The music is intended to mask the loud and decidedly unsettling noises made by the machine itself. To be honest I’m not sure which was worse.

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Blink and you won’t miss a thing

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Biology / Health / Myths / Psychology

You may not have noticed, but you spend about ten per cent of the time you’re awake with your eyes closed. I’m talking about the fact you blink your eyes every few seconds. Why do we blink so often and why don’t we notice the world plunge into darkness every time we do?

Don't be afraid to blink; you won't miss anything! Image credit Randy Wick via Flickr

Don’t be afraid to blink; you won’t miss anything! Image credit Randy Wick via Flickr

Be clean, eyeball

If you’re awake for 16 hours a day, you have your eyes closed for more than an hour and a half each day. That seems a lot and suggests blinking must be doing something important. The most obvious explanation for blinking is the fact a blink clears away any pesky dust particles that might have landed on your eye. Blinking also keeps your eyeball moist. Each blink lasts only a fraction of a second, but that’s enough time to spread the perfect mix of lubricating fluids across the surface of your eye. Is it as simple as that? Yes, and no.

The act of blinking does keep our eyes clean and lubricated, but research has shown we wouldn’t need to blink nearly so often if that were the main game. Think about the last time you had a staring competition: you were easily able to stop blinking for far longer than a few seconds. There’s more going on when we blink than just a cleaning service.

A clue as to the role of blinking is when we blink. You might think blinking is random, but it’s not. We blink at predictable times. When reading, we blink at the end of a sentence. When listening to someone talking, we blink during natural pauses in speaking. And when watching a movie, we blink during scenes when the action lags. Perhaps just after something important has happened or when the main character is briefly out of shot. And what’s more, if we’re watching with friends, our blinks tend to be synchronised. One fascinating study found skilled magicians take advantage of synchronised blinking to hide the secret of their illusions.

A moment of calm

Scientists interested in the timing of our blinks measured people’s brain activity while watching Mr. Bean. (Apparently Rowan Atkinson is very effective at synchronising blinks). The idea was to work out which parts of the brain were more or less active during blinking. They found during blinking, there’s a spike in activity in the areas of our brain involved with the ‘default mode of brain function’. Default mode is how your brain operates when you’re in a state of calm, wakeful rest, not distracted by what’s going on in the outside world. It’s the same mode of brain function often brought on by silence. Perhaps blinking is a way to snatch a quick mental time-out every few seconds.

To test if this little mental break is simply the result of not seeing anything for a brief moment, the researchers inserted tiny blackouts in the video – a blank screen that lasted for the same amount of time as a blink. But looking at the brain again, the default mode didn’t kick in during the blackouts. So for our brains, blinking is more than not seeing anything for a moment. The researchers suggest these brief moments of calm and introspection may help us focus and to pay more attention to the world around us when we open our eyes again.

I can see the light

An odd thing about blinking is that we’re barely aware we do it. If you were to sit in a windowless room and I turned the lights off and then on again every few seconds, I reckon you’d notice. In fact I’d be willing to bet you’d get pretty annoyed. But that’s similar to what’s happening every time you blink: the world goes dark for a moment. Yet we don’t feel as though our view of the world around us has been interrupted at all.

What is going on in our brains to allow us to be oblivious to these moments of darkness? Research out last week tested two possible answers. Firstly, that after each blink, our brain backdates what we see. In this case, we assume what we see after a blink was also true during the time our eyes were closed. Our brain simply fills in the gap. A second possibility is that our brains hold onto the image of what the world looked like before the blink and assume this to have continued during the time our eyes were closed.

To test these two possibilities, scientists used some nifty experiments involving flashing a letter on a screen. Students taking part in the study had to say how long the letter appeared on the screen when they were allowed to blink and again when they weren’t. But the results of the study suggest neither of these theories is right. The study participants simply underestimated how long the letter was visible for when they blinked. This suggests our brains just ignore blinks, momentarily shutting down our perceptions of the outside world. What we still don’t know is how our brains make the world appear continuous despite our blinks. But I know that next time someone says to me ‘Don’t blink or you’ll miss it’, I’ll remember a blink may be just the time-out my brain needs.

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A phantom menace

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Health / Medicine / Myths / Psychology

Virtually all amputees experience ongoing sensations in their missing limb, and many also experience intense pain: phantom limb pain. How on earth can you treat pain in a body part that doesn’t exist? And what is causing the pain in the first place?

Many amputees feel ‘phantom’ pain in their non-existent limbs.

Many amputees feel ‘phantom’ pain in their non-existent limbs. Image credit David Ingram via Flickr

The pain is real

One of the most famous examples of a phantom limb belonged to Lord Horatio Nelson, a much-decorated British Naval officer. In 1797, he had to have part of his arm amputated after it was shot in battle. He went on to experience severe pain in his missing arm and hand, including the sensation that fingernails were digging into his palm. Nelson used this experience to argue for the existence of the soul: if his arm could ‘survive’ being destroyed, why not an entire person?

Phantom limb pain is extremely common. In a study of 5000 veterans post amputation, 78% experienced it. Sufferers explain that a phantom limb can experience all the same sensations a real limb can: pain, heat, sweating, tingling, paralysis and movement. And phantom sensations don’t only occur in limbs. Up to 80% of women experience phantom breast pain after a mastectomy. Some women also report a phantom uterus with monthly cramps after a hysterectomy.

Perhaps one of the only vaguely similar experiences non-amputees can have of phantom pain is after a local anaesthetic at the dentist. Your nerves go dead, but you don’t feel like your lips and cheek have disappeared. If anything they feel swollen and puffier than usual.

All in the mind

At first glance, phantom pain seems exceedingly odd – and that’s putting it mildly. How can a body part that doesn’t exist experience pain? But if we think about what pain actually is, phantom pain becomes easier to understand. Put very simply, pain is a perception similar to hearing or smelling. If you break your arm, nerve cells in your arm send a message to your spinal cord and then onto the brain to indicate there’s a problem. Your brain translates this message and perceives the feeling of pain. The pain is in your brain.

For a long time, it was thought phantom limb pain derived from inflamed, irritated or frayed nerve endings in the stump sending incorrect messages to the brain. In the past, doctors sometimes performed surgery to remove more of the stump in the hope of fixing the problem. But it didn’t work.

Your plastic brain

Our current understanding of phantom limb pain highlights how extraordinary our brains are. Inside your brain is a virtual, sensory model of your body. In effect, your brain contains a map of your body, but composed of brain cells. Each of your body parts has a corresponding section of the map in your brain. Research suggests that if some parts of the map are inactive (for example, as a result of amputation), adjacent areas of the map begin to take over. So the nerve connections in the brain become reorganised and that’s what we refer to as brain plasticity.

Researchers have shown the part of the brain’s sensory map that used to represent the now-amputated limb can be taken over by representations of different body parts. In the case of arm amputations, the areas that have been found to take over are the face and lips. This is because in the brain’s map, the face and arm areas are right next to one another. This means touching an affected person in particular places on the face results in corresponding feelings in the phantom limb. Scientists have been able to draw on the faces of amputees (literally, with a texta), to show where the missing limb and digits are felt.

Gaming to tackle pain

For many years, phantom limb pain proved incredibly difficult to treat. Drugs don’t tend to work. How do you treat pain that is perceived to occur in a body part that doesn’t exist? Of course, you don’t; you treat the brain, which is where the sensations originate.

One of the first successful treatments for phantom limb pain is deceptively simple, and impressively cheap. In some cases, all that is required to retrain the brain is a mirror. Mirror therapy provides the brain with an opportunity to match what it sees with what it feels. A person suffering from phantom limb pain can position a mirror so that the reflected limb seen in the mirror appears to be the amputated limb. The limb can be moved and stretched and many people have reported huge reductions in pain as a result.

A slightly higher-tech and very promising treatment for phantom limb pain is augmented reality. This technology enables a wider range of motion of the replacement limb and incorporates gaming to keep patients motivated to do their exercises. Truth be told, we don’t fully understand why these treatments work. But whatever extraordinary brain tricks are going on, I’m guessing phantom limb pain sufferers will be happy to play the game.

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The silent treatment

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Anthropology / Biology / Health / Medicine / Psychology

Stop right now and listen. What can you hear? I’m betting you can hear something: it’s a noisy world we live in. You’re probably well aware that too much noise is bad for you. As well as obvious problems like hearing loss and ringing in the ears, noise has been shown to cause stress, insomnia and even heart disease. New research suggests it’s time we embraced the power of silence.

How's the serenity? Science says silence is good for the brain.

How’s the serenity? Science says silence is good for the brain. Image credit Moya Brenn via Flickr

Silence is golden

If you’re anything like me – young kids, a busy job and an addiction to good conversation, podcasts and audiobooks – there’s probably a distinct lack of quiet in your life. But beyond all the wonderful sounds I choose to surround myself with, there’s also plenty of noise, sounds I’d rather not have to listen to. Traffic, the building site right outside my window at work and annoying mobile ringtones, to name a few.

The word ‘noise’ comes from the Latin meaning pain or queasiness. And noise, now often referred to as noise pollution, has been blamed for a variety of ills. Sleeping problems, high blood pressure, difficulty concentrating and heart disease are some of the main concerns. And noise can also simply get to us, hence the diagnosis of ‘noise annoyance’. Sound vibrates the bones in our ears, which get converted into electrical signals to our brain. Our bodies respond to these signals, often resulting in the release of stress hormones like cortisol. Noise has this effect even if you’re sound asleep, and it’s not good news. If you live in a noisy place, you’re probably also living with permanently high levels of stress. Kids living in noisy places may experience learning difficulties amongst other problems.

What to do about it? Research suggests that it’s not enough to simply seek a little peace and quiet, but that silence is more powerful than we ever guessed.

Of mice, memories and music

Ten years ago, scientists who were also amateur musicians wanted to study how music affects people physiologically. Study participants listened to a two-minute track of each of six different music styles, with a two-minute break between each track. The researchers measured breathing rate, blood pressure and various other physiological changes. They were expecting to find the tempo, rhythm and melody of the music as well as people’s previous musical training and own musical preferences to have an effect. And they did find these things. But the biggest finding of the study was something the researchers didn’t even set out to look at: it was the two minutes of silence between tracks that had the biggest relaxation effect.

More recently, researchers studied the effects of various sounds on the brains of adult mice. The sounds of interest were music, baby mouse calls and white noise. Silence was used as a control for the experiment. Again, without trying to, this study showed the power of silence: none of the actual sounds had a long-term effect on the brain. But two hours of silence a day had a profound effect on the mice brains: they developed new brain cells in the hippocampus, an area of the brain responsible for emotions and memory.

Quieting the mind

At some level we all know quiet is good for us. Sales of noise-cancelling headphones have sky-rocketed in recent years and Finland’s Tourist Board’s slogan ‘Silence, Please’ has been a massively successful way to market the country to the world. Most of us have a strong sense that time in nature will do us the world of good and this is at least partly due to the quiet that can often be found in natural places.

Your brain is always active, but when it’s not distracted by noise, or being required to focus on a particular task, it enters a state called the ‘default mode of brain function.’ This is when our brains get to do a bit of housekeeping: processing messages that come both from the outside world and from within ourselves. In silence, our brain has the opportunity to integrate these messages. We can reflect on who we are, empathise with others, reflect on our own wellbeing and think creatively. Silence allows us to connect with ourselves and replenishes our inner reserves.

Too much of a good thing?

So does all this mean the more quieter the silence, the better? Not so fast. The most silent place on earth, an anechoic chamber in Minnesota is so quiet that the background noise is measured as a negative. This means you can hear your heart beat, your stomach gurgle and sometimes even your nerves firing. It’s a place companies can test the volume of their products and where NASA can send astronauts to get a taste of the silence of space.

But if you think it would be a great place to hang out and grow some new brain cells, you’re wrong. Most people find the room deeply disorientating. Reports are that the longest anyone has even been able to cope with staying in the room is 45 minutes.

I reckon I’d rather head to Finland, thanks.

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