The Promise of Poop: Faecal transplants to treat C. difficile infection – An age old therapy moving into the light?

Clostridium difficile – a hospital superbug?

Clostridium difficile is a bacterium that is commonly found in the environment around us – in soil, air and water. C. difficile is also present in the gut of up to 3% of healthy adults and 66% of infants, but rarely causes any problems in healthy people. This is because it is usually kept in line by the normal bacterial population in the intestine. However, when people undergo antibiotic treatment, this can disrupt the balance of bacteria in the gut, allowing C. difficile to rapidly multiply and cause illness. C. difficile infection (CDI) can result in very mild diarrhoea, but can also result in some particularly nasty, life threatening symptoms, that in the extreme can lead to someone having their colon surgically removed.

Clostridium difficile

Clostridium difficile – a ubiquitous bacterium

CDI is the leading cause of infectious diarrhoea in healthcare institutions worldwide, and the problem doesn’t seem to be going away anytime soon. In fact, over the last decade CDI has become more frequent, more difficult to get rid of fully and more often actually causes death. This is thought to be due to the emergence of more aggressive C. difficile strains.

CDI is commonly treated with antibiotic therapy, but this is by no means the perfect treatment option as it is becoming increasingly associated with treatment failure and return of infection. In addition, CDI weighs a heavy financial burden on healthcare systems across the world, each case costing approximately £4000. This particular conundrum has led to a race in the development of alternative treatment therapies for the disease and has recently reignited the interest in an age old therapy: the faecal transplant.

What is a faecal transplant?

The faecal transplant has been knocking around for centuries, with its first use to treat diarrhoea being described all the way back in 4th century China. Possibly one of the reasons it hasn’t proved so popular is due to the fact that it sounds so disgusting. The faecal transplant involves the transfer of poop from a healthy individual to the gut of a patient to cure their disease. Obviously, there is only one of two routes to administer this lovely load; via a nose tube directly into the stomach (apparently rather unpleasant when the patient burps) or through colonoscopy. I think we can all agree that neither of these options seems at all appealing, but treating patients with CDI with faecal transplants does seem to work.

Indeed, clinical trials suggest that the faecal transplants are both well tolerated and very effective. In the most recent study carried out in the Netherlands, published in the New England Journal of Medicine earlier this year, it was found that that faecal transplants cured 15 out of 16 patients with recurring CDI – a 96% success rate compared to less than 30% for standard antibiotic therapy.

So, what is the science behind a faecal transplant and why does it work?

It is estimated that over 4000 bacterial species reside in the gastrointestinal tract, and amazingly, we are inherently outnumbered by the number of bacteria that live in our body. The human microbiota contains as many as 100 trillion bacteria, which is ten times greater than the number of human cells in our body. Not to worry though folks, these bacteria are friends, not foes.

In fact, it has become very apparent in recent years that friendly bacteria residing in the gut do their bit to keep us healthy. A number of diseases, including cancer, inflammatory bowel disease and arthritis, are linked with changes in the make-up of the types of gut bacteria. With respect to C. difficile infection, the disease most commonly arises in patients who have undergone antibiotic therapy, which results in the disruption of their normal intestinal microbiota. Antibiotics can wipe out the good bacteria in the gut that usually provide a protective defence against C. difficile, allowing it to flourish and cause infection.

With this in mind, a faecal transplant doesn’t seem so daft. Transferring poop from a healthy donor to the gut of a patient with CDI is thought to restore the good bacteria for them to help fight C. difficile, preventing any further disease.

Can we get past the yuck factor?

We know that the results from clinical trials suggest that the faecal transplant not only works, but is well tolerated: the two gold stars with respect to disease therapy. But the fact remains that the faecal transplant is also, quite frankly, gross. People often don’t like the thought of taking others seconds or leftovers – is this treatment taking it one step too far?

Testimonials from patients treated with the faecal transplant suggest quite the opposite; these patients have won their battle with CDI and changed their life thanks to the unusual therapy. They are all more than happy to recommend it to others.

Yes, we know that the faecal transplant is not pretty, but neither is the possibility of major surgery leaving us with a stoma bag because all other treatment has failed.

Which option would you choose?

SSAThis post, by author Hannah Simpson, was kindly donated by the Scouse Science Alliance and the original text can be found here.

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The science behind Game of Thrones:

Spoiler alert: This article refers to events up to Season 4 Episode 2 of Game of Thrones. Please do not continue reading unless you have watched up to this point! Please do not include book spoilers in the comments section.

After taking time to pick my jaw up off the floor in the wake of GOT’s Purple Wedding, this week I’ve decided to indulge my inner geek and take a look at some of the amazing real-world science which courses through the fictional land of Westeros. So sit back, relax and wonder at resurrecting reptiles, ancient beasts, amazing brain imaging and the real-world poisons that finally wiped the smirk of King Joffrey’s face.

Dragons in stasis:

Who can forget the iconic moment when Daenerys (Dany) Targaryen (mother of dragons) emerged from the flames, unscathed and cradling a small brood of adorable baby dragons. Although I can’t vouch for the scientific realism behind Dany’s apparently flame retardant skin; it seems that George R. R. Martin may have borrowed the idea of embryonic resurrection from real-life reptiles.

DanyA number of reptiles, including turtles and chameleons, show an adaptation known as arrested embryonic development. This adaptation means that developing reptiles can remain arrested (paused) at an early stage of development, safely locked away inside their protective egg shell until environmental conditions are favourable for them to break free and explore the world. Apparently, in the case of dragons, this tends to be during periods of prolonged and intense heat. Interestingly, this form of arrested development is more common in species that lay thicker-shelled more rigid eggs – like dragons perhaps?

However, this theory falls short if you consider the apparent age of Dany’s dragon eggs – these being around 150 years old. Real life reptile eggs expressing arrested development, also known as diapause, tend to only remain dormant for a maximum period of a year – any longer and the embryo is likely to die. This is a fair way off the 150 year mark, however, if we throw invertebrates into the mix, we find reports of life emerging from eggs which have laid dormant on a museum shelf for over 120 years (specifically Tardigrade or waterbear eggs)! So, scientifically speaking, it seems Dany’s dragons are a hybrid between modern day reptiles and invertebrates with the ability to remain dormant for many years; a terrifying mesh of science fiction and science fact which will hopefully soon burn a path directly to the Iron Throne for our bad-ass dragon queen!

Dire wolves:

With wild burning eyes and powerful bone-breaking jaws the dire wolf, sigil of the ill-fated house Stark, is not only a formidable creature, but also one which does not stem purely from science-fiction. Indeed, dire wolves, also known as Canis dirus (meaning fearsome dog) are known to have roamed the Earth along with other megafauna such as giant sloths, woolly mammoths and giant beavers over 10,000 years ago.

Dire_Wolf_SkeletonThe average dire wolf would have been roughly the same size as a grey wolf; averaging about 1.5m (4.9ft) in length, but with a significantly heavier build, weighing between 50kg (110lb) and 79kg (174lb) – making them the largest species in the genus Canis. Their teeth were also relatively large leading palaeontologists to suggest that these were used to crush bone. The animals were once common throughout North and South America; indeed, dozens of dire wolf fossils have been recovered from the La Brea Tar Pits in Los Angeles.

Was Khal Drogo really brain dead?:

khal_drogo_by_sanxtv-d5nxjp1Whether Dany’s feelings for Khal Drogo stemmed from true love or Stockholm syndrome, I couldn’t help but feel sad when this unexpected love story drew to an abrupt and tragic end. The enigmatic powers of blood magic appeared to leave poor Drogo in a vegetative state, but what was really going on behind his inscrutable gaze?

Modern imaging science is now revolutionising our understanding of vegetative states and is providing a window into the minds of otherwise unresponsive patients. A vegetative state is defined as when a patient is awake, but shows no signs of conscious awareness. Due to the unresponsive nature of most vegetative patients, you may be forgiven in assuming that they are actually brain dead and incapable of responding. However, recent ground-breaking work using fMRI has revealed that, in some cases, vegetative patents have an intact conscious mind and, by controlling their brain activity, can clearly provide yes or no answers to simple questions. This can be seen in the astounding video footage below where a Canadian man (Scott Routley) who, for over a decade, was believed to be in an unresponsive ‘vegetative’ state is able to ‘talk’ to scientists through an fMRI and to indicate that he is not in any pain.

Perhaps if Vaes Dothrak had state of the art fMRI equipment this little love story may have had a happier ending?

What killed Joffrey?:

joffrey_baratheon_by_slashaline-d79pz1sOK, so I think we can all agree that no one was particularly upset by the death of this smug teenage tyrant with more power than sense. But, following the particularly graphic and gruesome portrayal of Joff’s final moments, I question; was this death purely a work of fiction or is such an end possible with the use of real-world poisons?

To answer this question we must first consider Joff’s dying minutes:

Joff’s final moments followed from a sip of wine and a bite of pie; either of which could have been the vessel for this deadly dram. The first observable symptoms of this poisoning, manifest as a dryness in his mouth, followed by an intense coughing fit.

Gasping for breath he soon falls to the floor and vomits. Unable to stand, he lays fighting for breath and convulsing. Cersei rushes to help her son, turning him over and, in the process, revealing a grey/blue pallor to his face and lines of fresh blood coursing from his nostrils. After a final plaintive glance towards his mother (which almost convinces us he may actually be human), he rapidly dies in her arms.

From these symptoms we could conclude that whatever poison was used must have the following properties:

1) It must be fast acting.

2) It must cause respiratory distress, perhaps through pulmonary oedema (a build-up of fluid in the lungs).

3) It must cause haemorrhage, perhaps by thinning the blood, or preventing clotting.

Although there are no real-world poisons which can create this exact collection of symptoms alone, a number may induce similar effects and, in combination, may replicate George R. R. Martin’s fictional strangler.

One substance which fulfils both criteria 1 and 2 is cyanide. It only takes a small amount of cyanide to produce a toxic effect and the poison is quickly adsorbed into the body through the gut. This poison causes a burning sensation in the throat and also leads to pulmonary oedema which, more often than not, can trigger violent coughing fits. Cyanide poisoning also fits well with the observation of vomiting and a bluing of the skin. Since cyanide interferes with the body’s ability to generate energy in its cells, these cells begin to die and, as death nears, the affected person’s skin can turn blue – a clinical effect called cyanosis.

Another possible candidate toxin is Deadly nightshade. This potent poison disrupts nerve cell communication, causing convulsions, dry mouth, a sense of choking and dilation of blood vessels – turning the victims face red. However, neither cyanide or Deadly nightshade commonly lead to haemorrhaging.

Haemorrhaging may be caused by agents which prevent clotting and thin the blood, a well known example being warfarin, found in pesticides. However, the effects of warfarin are commonly not seen until several days after ingestion, meaning that this poison is too slow to be our candidate. A number of snake venoms also thin the blood, meaning that perhaps the poison used to kill Joffrey was a mixture of more than one toxin.

It is, however, also possible that the haemorrhaging seen at the purple wedding was simply caused by the violent coughing fit Joff experienced before his death.

So, the most likely candidate poison seems to be cyanide, perhaps mixed with a blood thinning venom. But, whatever the cause of death, the biggest question still remains…who put it there? With such a renowned and despised groom, anyone could be a suspect; sadly though, this is one question science can’t answer…I guess we’ll just have to wait and see!

Note: for a more in-depth discussion of Joff’s poisoning see this great article by Rachel Nuwer.

So there we have it. The fictional world of Westeros is actually awash with scientific fact. Be it ancient wolves or reptilian resurrection, science can give us valuable insights into the dramatic events of Game of Thrones. It probably cannot explain why someone might kill a whole family at a wedding though…

Post by: Sarah Fox

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Is pressure to publish causing scientific fraud?

A paper which was widely regarded as an exciting breakthrough has come under scrutiny, with some people suggesting that the results were false, or even fabricated. This is not the first time that a major study has been subject to accusations of fraud. Is there a reason that some scientists are willing to disregard scientific integrity in order to publish?

scientist stock photoIn January 2014, researchers at the Riken institute in Japan published a paper stating that they had found a simple way to make stem cells from adult cells. All you needed to do was wash the adult cells in acid and they would revert back to their stem cell form. The study was published in the top journal Nature and caused a ripple of excitement in the scientific community – stem cells are an extremely useful but controversial tool and finding a way to make them so easily, and without any ethical problems, was considered a game-changer.

However, doubt began to arise about these so called STAP (Stimulus-Triggered Acquisition of Pluripotency) cells as other labs were not able to reproduce the results. The lead author of the paper, Haruko Obokata, has been found guilty of misconduct after investigators at the Riken institute found that some images had been manipulated. However, this did not directly affect the result of the paper and Nature has not retracted it. Dr Obokata has apologised for the mistakes but maintains that her results are genuine. The latest twist in the tale is that an independent scientist, Kenneth Ka-Ho Lee, has managed to recreate STAP cells using a different method, although his results have yet to be verified.

Dr Obokata and her team are not the only people to have published in a high-level journal to then be suspected of fraud. The most infamous example is ex-Dr Andrew Wakefield, whose study into a link between the triple MMR vaccine and autism was published in the Lancet and widely publicised in the media. Subsequently, a thorough investigation discovered huge amounts of misconduct and fraud. Another example from the field of stem cell research is the South Korean researcher Hwang Woo-Suk, who published a series of high profile articles in Science suggesting that he had achieved human cloning; it later turned out that these results had been falsified.

But this blog post is not about whether the STAP cell result was genuine or not; that is up to the investigators and other stem cell biologists. The question I’m asking here is – how and why does scientific fraud occur in the first place?

Pressure to publish well

doctor with a headache - pressureWhen the validity of a scientific article comes into doubt, it is often retracted by the journal (the website Retraction Watch monitors this). Journals are ascribed an “impact factor”, giving an idea of how influential the journal is in scientific circles. Those with the highest impact factors include Nature, Science and Cell. These high-impact journals have amongst the highest rates of retraction. This indicates that the more prestigious the journal, the more likely it is that people may fake their results to get published in them.

Why would people fake results to get published in a better journal? The answer is simple and unsurprising: money. The more papers you publish in high-impact journals, the more publicity you get and the more likely you are to be able to secure grants to continue your investigations.

Researchers at the beginning of their careers, like Dr Obokata, may feel under pressure to perform almost-miracles to get their results published in a high-impact journal. The pressure may come from their immediate boss, or the institution, or the fact that other researchers are working on the same thing – publishing breakthrough results first is always the key to getting into high-impact journals. In some cases, this may lead to the fabrication of good results in order to try and relieve some this pressure.

Just plain old greed

moneyThere are some researchers, Andrew Wakefield and Hwang Woo-Suk amongst them, who wilfully commit fraud for monetary gain – not just through increased grants but from private companies. Wakefield was developing his own single vaccine for measles, and so had a vested monetary interest in discrediting the triple MMR vaccine. Woo-Suk embezzled a lot of the money given to him to carry out this research.

It should be pointed out that scientists such as this are extremely rare. Ethics and good lab practice are taught and enforced throughout degrees and at PhD level. The majority of scientists realise that faking results would ultimately lead nowhere.

An honest mistake

One of the reasons that the warning flags went up about the STAP cells is that other labs could not reproduce the results as described in the paper. Reproducibility is the cornerstone of a good scientific finding – it is only considered to be a genuine result if independent labs can recreate it. However, there are many differences between labs – techniques, reagents and work ethic are variable. This means that it may actually be quite difficult to exactly recreate someone else’s work. Therefore it may be that a difference in techniques or practices is causing these problems, rather than direct fraud. If this is the case, it does not mean that the result is fraudulent, but maybe that it is not as far-reaching or ground-breaking as first thought.

A lot of scientific “fraud” or retracted papers could possibly be attributed to the researchers accidentally misinterpreting results or unwittingly doing something during the protocol which has affected the result. Scientists are people too and mistakes are made; some are just more high profile than others.

This point comes back around to the pressure to publish. With the need to get good results out quickly, it’s possible that these mistakes happen because the researchers are rushing to get their results out to the good journals.

A problem with the peer-review process?

magnifying glassArticles published in high-impact journals have to go through a process called peer review, where study results are scrutinised by other top scientists in the field. This is supposed to filter out the questionable results, so that only good science gets published. However, peer reviewers can only study the presented results; it is not always possible to detect a fraudulent result this way. The benefits versus problems with peer review are outside of the scope of this article and have been discussed at length elsewhere, but the fact that the peer reviewers can be fooled by fraudulent results may contribute to the reason that some scientists risk it.

Scientific fraud is still relatively rare but does exist. So far it is unclear what the best way is to combat it, because publication in high-impact, peer-reviewed journals remains the best way to get results out to the scientific community. Possibly more transparency between different labs would help – then results can be tried for reproducibility prior to initial publication.

Whatever the answer, this example and others alike represent a problem that must be addressed. Apart from the obvious impact on the scientific community, the public’s belief in scientists and scientific research is strengthening all the time; stories like the STAP cell report are damaging this fragile trust. Steps must be taken to prevent researchers sacrificing scientific ethics and integrity under the pressure to publish well and for monetary gain.

Post by: Louise Walker

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The elephant: the largest living land animal

Elephas_maximus_(Bandipur)From the killer whale whose heart is large enough to fit a small car inside, to the crocodile whose lungs are able to move around within its body cavity to alter its centre of gravity: the animal kingdom contains some of the most fascinating and unusual organisms that live on the Earth. It’s the fascinating adaptations found throughout the animal world that fuels our interests in these animals.

For years the extraordinary elephant has roamed south-eastern Asia and Africa.  Weighing up to six tonnes and reaching up to four metres in height, the elephant is an extremely impressive animal; in fact the largest of all land animals. Despite their vegetarian diet, getting into a fight with an animal of this size should be avoided at all costs!

The big question is how have their systems adapted to meet the needs of this monstrous body?

We know the elephant has in excess of 200 bones that make up its skeleton- hardly surprising given that it needs to support its sheer size. In keeping with its frame, the elephant also has a huge skull, but what is perhaps surprising is its relatively small mouth.  Due to the nature of the tough vegetation that elephants eat, they have evolved to have 8 teeth the size of bricks.  The surface of the teeth are covered in tough enamel ridges that grind vegetation into a pulp as the jaw moves back and forwards.  As old teeth become excessively worn, new teeth are produced at the back of the mouth. The new tooth gradually moves forward, pushing the worn one towards the front of the jaw.  It is this conveyor belt action that allows elephants to eat throughout their entire lifetime.

Another fascinating, and obvious, feature of the elephant is their tusks. They are basically huge incisor teeth, used primarily as a defence mechanism (who wouldn’t be scared of two huge sword-like projections?) as well as for foraging food.  Male elephants also use their tusks to dominate other males, and to help find themselves a mate. The pair of huge tusks is an obvious show of natural selection; in this case, the bigger the tusks the better. The largest known tusk was a whopping 3.5 metres in length.

However, in recent years we have seen a dramatic reversal in the tusk stakes. Due to pressures from hunters and poachers, having large tusks makes these elephants a prime target. It is for this very reason that we are now seeing a very obvious reduction in the size of elephant tusks.

Elephant_snorkelingYet another amazing adaptation we see in elephants originates from within their lungs. Unlike most other mammals, elephants’ lungs lack a pleural space separating their lungs from the ribs.  Instead, connective tissue connects the lungs to their ribcage and diaphragm. But what advantage might this have? Scientists believe that this incredible anomaly may have arisen to aid elephants in ‘snorkelling'; elephants are the only land mammal that are able to entirely submerge themselves in water whilst taking in air from above the surface. Without the lung-rib connective tissue, blood vessels in the lungs would most likely not survive the huge changes in pressure exerted on them whilst snorkelling. By covering these vessels in a much tougher membrane, they are protected from damage from changes in pressure. The downside to this tough casing is that the blood vessels aren’t able to produce a lubricating fluid necessary to ensure that the lungs and rib cage slide over one another during respiration. Without the fluid, the tough connective tissue only allows a small degree of movement. Despite perhaps negatively impacting upon respiration, the benefits that this connective tissue confers to the elephant far outweigh the negatives.

Angry_elephant_earsPerhaps even more fascinating is how an animal of this size, living in extremely hot regions of the world, manages to prevent overheating. They haven’t exactly been blessed with the ideal body shape to stay cool. To address this mystery, scientists used heat-mapping techniques to measure the external temperature of an elephant throughout the day, while also measuring the temperature from within the elephant.  Results found that whilst the surface of the elephant can reach up to 55 degrees Celsius, internal temperatures are kept far lower at around 35 degrees. So what exactly is allowing the elephant to remain cool?  We know that the answer lies with their ears. As with their skull, elephants have the largest ears in the animal kingdom. But these ears serve a very important purpose; they act as a massive fan working to cool down the elephant. By effectively ‘flapping’ the ears back and forth, air is forced back over the body. Big arteries from the body carry blood close to the ears surface via a series of smaller vessels. The ears are well equipped to deal with this, as they are extremely thin. It is this flapping motion of the ears that allow much of the heat from the body to be carried away, and hence prevents overheating.

Elephant_trunk_(1)And finally, I couldn’t talk about the mighty elephant without mentioning its most recognisable piece of anatomy. The trunk. This ingenious piece of machinery is involved in many things that elephants do; feeding and drinking, snorkelling, washing, playing, communicating, feeling, and manipulating amongst many others. This original piece of anatomy seemed to have evolved long ago through natural selection. The sheer size of an elephant’s body and head made bending down to pickup food an onerous task. This difficulty caused the trunk to evolve. Over many years it is thought that these animals slowly evolved to have a shorter jaw, but with a longer top lip.  As they became taller and taller, the upper lip gradually elongated until it resembled a trunk that was able to feed without having to bend down.

You might think of these animals as large, bulky and clumsy, but this is in fact far from the truth. They are amazing feats of engineering. We know that elephants are actually very elegantly made and adapted to suit their body’s needs from their trunk, their cooling system and to their lungs. Today elephants are the only animals of such size, so it is obvious that their size doesn’t hamper them; their body is doing something right.

Post by Samantha Lawrence

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Neuromarketing: a whole lot of fluff?

The camera pans across a dimly lit swamp. It picks up a bullfrog letting out a deep, loud “BUD”. Another frog joins in with a shrill “Weisssss”; their friend finishes off with a baritone “Er”. At first they call out haphazardly before synchronously calling to each other, “Bud” – “Weis” – “Er”. The camera zooms out, revealing a neon sign with the insignia, Budweiser.

This was a famous TV commercial from the beer manufacturer Budweiser that debuted during the Super Bowl in 1995. The memory of this advert remains with me today, and always puts a smile on my face, I’m not sure why, I’m not sure whether it necessarily makes me more likely to buy a Bud either, but it does stay with me.

Marketing has traditionally been thought of as an art. A creative business fronted by creative types who work hard to develop amusing, emotional and memorable campaigns which convince us we want/need to buy their product. Any metrics assigned to this process have classically been via standard market researcher questionnaires.

The problem with this, so the argument goes, is that people lie. They either tell you what they think you want to hear, genuinely can’t remember or just cannot imagine themselves in a real-life scenario which would allow them to give an accurate answer.

Becoming more and more prominent in this industry is a segment of advertising that claims to eliminate these problems by basing the research on science. Welcome to the increasingly lucrative world of neuromarketing.

Neuromarketing uses neuroscience techniques to try to understand why we buy what we buy, what is that certain je ne sais quoi that turns a product into a must-have?

One of the basic techniques is the use of eye-tracking software. Sensors on the edges of your eyes can track where you are looking at any time. Portable versions have been developed that allow companies to track your eyes as you look around a supermarket or watch a commercial. Companies can tell from this whether you’re looking at what they want you to look at.

In the video below you can see a 2011 advert from the car manufacturer Volkswagen where a child is dressed as Darth Vader and tries to use ‘the force’ to move things around the house. This is overlaid with research carried out at Sands Research Inc. in Texas, United States. In the top left of the video you can see the results of eye-tracking showing what subjects are likely to be looking at any one time.

From this we can see that viewers were looking at faces more than anything else. Also present in this analysis are brain recordings using electroencephalography (EEG). EEG electrodes can be placed all over the scalp and used to record electrical activity from various brain regions. Sands Research’s analysis ranked this advert from Volkswagen as the most engaging in their analysis of all adverts from the 2011 Super Bowl.

EEGDr. Sands, Chairman and Chief Scientific Officer of Sands Research, said, “As you will see in the Volkswagen ad, the positive and negative emotional response flows with the commercial and ends on an extremely positive point. By creating an engaging and emotional storyline with strong positive response, viewers were extensively engaged and strongly recalled the spot and more importantly, specifically recalled the brand associated with the commercial.”

This is where the field of neuromarketing gets hazier. Very few people would dispute the relevance of eye-tracking to make sure that viewers are focusing on what they should be focusing on. If the scene is too busy and there are too many distractions then the message will be lost. But, there is much scepticism around the idea that EEG recordings can tell us when people are more engaged.

For one thing, EEG recordings have poor spatial resolution. EEG electrodes are attached to the scalp, this means that electrical changes deep within the brain struggle to reach these electrodes and the signals that do reach them smear out to the point where you can’t really isolate the exact origin of this activity. Secondly, there is significant debate in the neuroscience community about what ‘activity’ in a certain region even means… For examples, see herehere and here – a more scientific explanation of some of the issues behind imaging experiments can be found here.

The main reason why scientists are sceptical of this type of analysis is that a number of the methods have not been published in peer-reviewed journals. There is some interesting published work (here for example) and some companies do publish some details of their methods, but scepticism is always necessary, even for published works.

Those in the scientific community who discuss these issues daily disagree about the best ways to analyse this type of data and what interpretations can be made. The idea that regions perform specific jobs and that measuring these areas can give us a score of complex human behaviour, such as how engaged or emotional we are, is therefore debatable.

Even so, the corporate world seems to be lapping these techniques up. Many campaigns are built on these data. Volvo had a large campaign at the end of 2013 claiming that their “car design [was] proven to be on a par with the most basic of human emotions”. Brain imaging is being used to understand what makes us enjoy a blockbuster film. It has also been used to see what effect celebrities have in a marketing campaign’s success.

It is hard to know how reliable this research really is as some of it has not been scientifically reported or scrutinised. There is a heavy amount of bias attached to these claims and if not properly reported, ‘neuromania’ can ensue. For now, be sceptical about what claims companies make about what your brain is telling you that you want. Even if a ‘neuromarketed’ magazine cover can increase sales.

Post by: Olly Freeman @ojfreeman

  • This post was altered on 30 March 2014. The original implied that all of this work was “based on methods which have not been published in peer-reviewed literature”. This is incorrect and reference has now been made to some peer-reviewed literature.

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The Health Benefits of Kissing

Pucker up, because it seems kissing has a number of important health benefits ranging Kissing1from improving mood and stress levels, to actually enhancing our bodies natural immunity to illness.

Mouth to mouth kissing is a behaviour seen in almost 90% of all human cultures, and used as a non-verbal communication of intimacy, affection and love. For centuries scientists have been pondering the origins of this primitive behaviour and whether it has a functional purpose in our lives.

So where did kissing come from? Apparently, the earliest record of kissing dates back to 1500 BC where references to  ‘drinking moisture from the lips’ were mentioned in Northern Indian Vedic texts. What’s more is that the Kamusutra, which details over 30 different types of kissing, dates as far back as the 6th century AD. According to Philematologists (scientists that study kissing!), it is hypothesized that kissing evolved from an early primitive behaviour known as the ’maternal permastication of food’, which quite literally involved the mouth to mouth contact between a mother and child in the exchange of food during infancy. Despite kissing not being a necessary requirement for successful reproduction, it is hypothesized that sexual kissing may have evolved from this display of care and affection, to eventually promote pair bonding and to facilitate in assessing mate suitability. While mouth to mouth contact is seen in numerous animals as part of courtship rituals, sexual kissing appears to be unique to our species, and may explain why our inverted shaped lips appear to differ from all other animals, almost as if they were shaped for such a purpose!

Despite the seemingly unhygienic nature of kissing, and the fact that it does expose us to the risk of oral infection, this primitive affectionate behaviour represents an evolutionary benefit in conferring protection from diseases that may impose more serious consequences. Mouth to mouth contact essentially exposes each person to the diseases of the other, which while not sounding particularly clean, can actually enhance our own immunological control of exposure to infection. Kissing2According to research by the journal ‘Medical Hypotheses’, kissing represents an evolutionary conserved biological behaviour that boosts our immunity to the Human Cytomegalovirus (HCMV). HCMV is a particularly nasty type of the Herpes virus that can carry a significant teratogenic risk for women i.e. it can have a severe impact on the their unborn children during development, if primary infection occurs during pregnancy. The risks to infected neotates include a number of serious development abnormalities such as enlargement of the liver and spleen, as well as a number of neurodevelopmental disorders including abnormal brain growth, seizures, cerebral palsy and mental retardation. For 30% of infected fetuses the disease is lethal, and as a result, numerous pregnancies are terminated if infection is detected. HCMV is transmitted in saliva, urine and semen. As the disease is only symptomatic during the active phase, it is not an easy virus to readily detect and thus avoid, especially when trying to conceive. In order to avoid infection of the HCMV during pregnancy,  researchers have hypothesized that kissing has evolved to allow women to control the time of inoculation, and that transmission of small amounts of the virus at this point through the saliva will confer immunity to the condition and prevent the presentation of symptoms.

It is now understood that affectionate behaviour has a number of stress-relieving effects. As stress, mainly via the ‘stress hormone’ cortisol, has a number of detrimental influences on our endocrine, nervous and immune systems, kissing may in fact confer significant health benefits by reducing these effects. Interestingly, not only does kissing improve our mood and thus reduce stress levels, it may actually act to reduce a number of parameters that are exacerbated by stress. Stress can elevate blood cholesterol levels, in one manner through stimulating the release of cortisol. Chronic elevation of cholesterol can lead to the build up of plaques and the clogging of arteries that may eventually trigger the development of coronary heart disease. It was identified that an increase in kissing behaviour between marital couples during a 6-week trial period lead to a decrease in blood cholesterol levels, and thus an improvement of blood lipid composition and reduced risk of cardiovascular complications.

Surprisingly, kissing may also enhance your dental health! While it wouldn’t be recommended as a replacement for brushing your teeth in the morning, the extra saliva generated during a kiss washes bacteria off your teeth, and as a result encourages the break down of oral plaque. Kissing also burns calories and raises your metabolism too. According to the research, a vigorous kiss burns up to two calories a minute and can almost double your metabolic rate (the rate at which you can process food). And it makes sense, as kissing involves the coordinated contraction of more than 30 facial muscles, the constant exercise improves muscular tone in the face.  One in particular, known as the orbicularis oris muscle, is used to pucker the lips and has been informally termed the kissing muscle. It has been suggested that the regular contraction of these muscles during a passionate kiss enhances muscle strength and tone and may actually contribute to maintaining a youthful complexion. So a passionate kiss may be the perfect non-surgical remedy for keeping your face young!

Kissing3On what is seemingly quite an obvious level, kissing enhances the release of endorphins in the brain and has a number of other emotional health boosting benefits that improve mood and mental well-being, reduces depression and stress, and most importantly promotes intimacy and pair bonding. So not that we need an excuse, but it seems that appreciating the importance of a good kiss will benefit your health and mental well-being in more ways than one, and if not for anything else, then use it as a happiness boost!

For more information see;

Hendrie CA and Brewer G (2010): Kissing as an Evolutionary Adaptation to Protect Against Human Cytomegalovirus-like teratogenesis. Medical Hypotheses 74: 222-224.

Floyd K, Boren JP, Hannawa AF, Hesse C, McEwan B and Veksler AE (2009): Kissing in Marital and Cohabiting Relationships: Effects on Blood Lipids, Stress, and Relationship Satisfaction. Western Journal of Communication 73: 113-133.

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Diving narcosis and laughing gas

Photo by Derek Keats

I watched a programme the other day about a deep sea mystery. A strangely high number of experienced deep sea divers had been lost on diving trips in a particular bay, and no one seemed to know why. The presenter, being a decent diver himself, went for a dive in the bay and noticed that he could make out the sunlight shining through the water at the other end of an underwater tunnel. His conclusion was that the now deceased divers saw this light and thought they could swim through the tunnel to the other side. What wasn’t obvious to the divers was that this light was deceptively far away and they would have to swim very fast for a long time to make it to the other end of the tunnel before running out of oxygen. But what could cause these supposedly experienced divers to make such a rash, fatal decision?

Nitrogen narcosis can give you tunnel vision, making it harder to read diving instruments. Image by RexxS

Above sea level, nitrogen is a pretty boring gas – it makes up about 80% of the air around us and doesn’t normally do us any harm. However, a problem arises when we breathe it in under high pressure – such as when diving. Several gases, including nitrogen, carbon dioxide, and oxygen are normally dissolved in our bloodstream. When you dive deep underwater, the increase in pressure exerted on your body by the surrounding water causes more of these gases to dissolve into your blood through your lungs when you breathe from the gas tank (because going deep-sea diving without a gas tank would be an even less recommendable thing to do). In fact, for every 10m a diver descends, their blood holds an extra 1.5 litres of dissolved nitrogen.

All that extra nitrogen rushing round in the bloodstream has weird, wonderful, and incompletely understood effects on the brain, collectively known as nitrogen narcosis.

Nitrogen narcosis is experienced by all divers – to varying degrees – and feels essentially like being drunk. Because of this similarity, nitrogen narcosis is often referred to as the ‘Martini effect’. Divers liken every 10m below sea level as the equivalent of having one martini – meaning they feel increasingly intoxicated the deeper they get. Even at comparatively shallow depths (10-30m below the surface), a diver will become less co-ordinated and a bit giddy – 20m lower they’ll start making mistakes and bad decisions and may start laughing for no reason. At 50-70 metres, they may start experiencing hallucinations, sleepiness, terror, poor concentration and confusion, and at 90m they risk losing consciousness or even dying.

So, the worse symptoms of nitrogen narcosis aren’t exactly like getting drunk, because even a huge amount of alcohol doesn’t give people hallucinations (though some alcoholics experience hallucinations when withdrawing from alcohol). Actually, the closest similarity to nitrogen narcosis you can find on dry land is from breathing laughing gas, or nitrous oxide.

A pretty sexist cartoon from ages ago showing some ‘scolding wives’ being prescribed laughing gas. I wonder why they were usually so unhappy with their husbands.

Nitrous oxide has been used by doctors to relax patients since 1794 and it is still used today as a form of pain relief for women during childbirth. It has been in the press a lot recently, dubbed ‘hippie crack’, as it’s often used recreationally (though usually not legally) for its mild hallucinogenic and euphoric ‘feel good’ effects, which have often been likened to nitrogen narcosis. So how does nitrous oxide affect the brain?

Although nitrous oxide is hugely understudied, there are several theories about how it can affect the brain. Because gases like nitrous oxide and nitrogen are really fat-soluble, they may interfere with cell membranes (which are made from fatty molecules) disrupting their normal function. In the case of brain cells, this may alter the way they communicate with one another. In addition, the dissolved gas molecules may directly bind to the receptors on the surface of brain and nerve cells. Nitrous oxide is used as a mild anaesthetic because it has been shown to block NMDA receptors – which normally ‘excite’ the brain – and because it activates potassium channels, which further suppress brain cell excitation. All this means is that brain activity is generally depressed and so users are more prone to making bad decisions or losing concentration.

As I mentioned before, nitrous oxide is also good for pain-relief, as it’s believed to activate opioid centres in the brain. When activated, the opioid system – the same one stimulated by drugs like heroin and morphine – then disinhibits certain adrenergic cells in the spinal cord, which dampen down any feelings of pain.

While there have been reports that nitrogen narcosis also decreases the perception of pain, it’s obviously difficult, and, well, not very practical to test the potential of high pressure deep sea diving on pain relief. Instead, what should be studied more are the effects of nitrous oxide on the nervous system. We’ve used the stuff for more than 200 years and yet the biology behind its uses and its dangers is still not fully understood. What’s more, the fact that people use nitrous oxide recreationally (and probably will continue to do so in spite of its non-legal status in many countries) means we really ought to know what its short and long term effects on the brain are. Unlike the mystery of the missing deep sea divers, the full extent of the ways in which nitrous oxide works remains unsolved.

Post by Natasha Bray

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