Posted in Psychology & Medicine

Stroke

A stroke is caused by a disruption in the supply of blood to the brain, which leads to cell death as oxygen is required. There are two types: ischaemic (where a clot cuts off blood supply to an area of the brain by blocking an artery) or haemorrhagic (when a blood vessel ruptures and leaks blood instead of delivering it to tissue). The most common cause of a stroke is a clot that made its way up to carotid arteries into the brain until it wedges in small vessel. There are many risk factors for blood clots, such as smoking, high cholesterol levels, atrial fibrillation and long distance flights.

Because the brain is always in high demand of oxygen (taking 20% of the total oxygen available), strokes can produce devastating effects within minutes. 5 minutes of oxygen deprivation can lead to irreversible cell death, a principle that is also used in cases of shock, where the blood pressure is too low to supply organs, or cardiac arrest. Therefore, it is crucial to recognise a stroke early so that an ambulance may arrive and deliver clot-busting medication such as streptokinase.

The FAST mnemonic is an effective way of remembering the common signs of a stroke. It is also useful in reminding people to respond fast.

  • F – Facial weakness: Is the person’s smile crooked? Disrupted brain function causes facial weakness on the opposite side. The weakness is usually seen around the mouth or eyes.
  • A – Arm weakness: Can the person keep both arms outstretched? This is related to motor function of the brain.
  • S – Speech difficulty: Is the person’s speech slurring or are they having problems understanding speech? This is a combined result of impaired motor function and speech centres of the brain.
  • T – Time to act: Call an ambulance. NOW.

Posted in Psychology & Medicine

Hypocrisy

Often in life, we find that other people can be idiots, evil or both. Whether it be the girl working in the cafe that forgot your order, or your girlfriend who says she was late because of traffic, or the bastard that takes the last slice of pizza. But then, when we do that exact same thing that annoyed us so much when someone else did it, we somehow always find an excuse that rationalises our act.

This can be explained by the phenomenon of special pleading. Instead of acknowledging the fact that what you did was incredibly rude or obnoxious, your brain automatically creates an exception to the rule. You forgot that customer’s order because you were having a bad day. You were actually late because of traffic. You took that last slice of pizza because you did not have as much as the others and everyone else looked full. This phenomenon rids us of feeling guilt after an “immoral” act and also enables our hypocrisy.

The best part is that we do not consciously know of our hypocrisy. The brain quickly devises a clever reason to explain why you are the exception to the rule, while everyone else is not. The reason is, as with so many other psychological phenomena, cognitive dissonance. The brain cannot comprehend that you would do something you find so detestable when someone else does it, so it forces itself to believe the reason it pulled out of the air to not feel guilty, as it is the only reason the brain can think of that explains your behaviour. Furthermore, as sometimes the excuses are true, our hypocrisy is reinforced and we continuously disobey the golden rule of “Do unto others as you would have them do unto you”.

Perhaps the more realistic, platinum rule should be: “Do unto others as you would have them do unto you…UNLESS”. It may not be a good moral system, but it sure explains the human condition of being an ass.

(Source: http://this-is-the-life2905.deviantart.com/art/the-only-exception-205009607)

Posted in Psychology & Medicine

Tetanus

Tetanus is an infectious disease caused by a soil-borne bacteria called Clostridium tetani. Patients are often infected soil entering the blood through deep wounds, such as a cut. The bacteria produces a toxin called tetanospasmin which leads to the characteristic symptoms of tetanus involving muscle.

The term tetanus actually refers to a state where skeletal muscle remains contracted and cannot relax due to maximum signalling from the nervous system. Tetanus is associated with some distinct symptoms involving tetanised muscles.

Tetanus starts in the face in the form of lockjaw (jaw clamps shut and cannot be opened) and sardonic risus sardonicus. Risus sardonicus, also known as sardonic grin, is a contorted, malicious-looking smile that is caused by spasms of muscles in the face. A good portrayal of the grin is seen in the Joker’s face from the Batman comic book series.
The disease then progresses to cause stiff neck, spasming of chest and leg muscles and difficulty swallowing. 

A dramatic symptom is opisthotonos, where the patient experiences extremely painful contractions of back muscles causing them to arch their back against their will. Along with lockjaw and risus sardonicus, it is a characteristic sign of tetanus and has been known for centuries. Before it was attributed to tetanus, people used to think the person was possessed by a demon due to the agonised screams and involuntary spasming of the body.

The disease is especially devastating in infants and can be spread to the fetus within the womb. This is because babies do not have a developed passive immune system that can combat the infection. Neonatal tetanus carries a mortality rate of over 90% and is responsible for 15% of all neonatal deaths.

Tetanus is a preventable disease through immunisation. Immunisation is done by injecting an inactive form of the toxin (i.e. cannot cause disease), inducing a reaction by the immune system. This essentially “teaches” the immune system to defend the body against tetanus. By completing a course of three doses and receiving occasional booster shots throughout life, tetanus can be prevented. Pregnant women must be immunised against tetanus to prevent neonatal tetanus (the babies receive scheduled immunisations soon after birth too).

This is one example of how immunisation can effectively prevent fatal diseases in a population.

Posted in Psychology & Medicine

Hypnagogia

Every person has had the experience of having a few seconds of brilliance just before their consciousness slips into sleep. During this short moment, we have some of the most creative and innovative ideas. Unfortunately, this is all lost by the time we wake up. This state is known as the hypnagogic state and has been well known since ancient Greece. Many philosophers and writers such as Aristotle and Edgar Allan Poe have written on the subject and how they received some of their greatest ideas in this state. 

Recent researches show that during hypnagogia, thought processes and cognition vastly differs to normal wakefulness. It appears that hypnagogic cognition is more based on the subconscious mind, with people in this state being more open to suggestion (e.g. hypnosis). Ideas seem to flow in a fluid yet illogical way and they are based on external stimuli, thus explaining the heightened suggestibility as the brain incorporates the surrounding into its thought process. The thought process is also less restricted, leading to openness and sensitivity. A process called autosymbolism occurs where abstract ideas that we are thinking are converted into concrete images. This explains the artistic inspiration seen in hypnagogia.

One of the more pronounced phenomena of hypnagogia is insight. It has been noted by many people throughout history that the moment before sleep is when we have the best ideas. For example, a chemist called August Kekulé realised that benzene was a ring structure after seeing an image of snakes biting each other’s tails to form a ring. Because of this, many famous artists and inventors tried to harness the power of hypnagogia through techniques such as the Dalí nap. Thomas Edison, Isaac Newton, Beethoven and Richard Wagner also practised similar techniques to gain insight into a problem that they were trying to solve or bring fresh ideas.

Another fascinating side of hypnagogia is the strange sensory phenomena associated with it. As in the case of sleep paralysis (which usually occurs in hypnapomp – the state between sleep and waking up), people often report strong hallucinations in the form of bright colours, geometric shapes, or even nightmarish visions (such as a ghost sitting on your chest). Other senses are affected as well, such as hearing whispering (commonly associated with the nightmarish hallucinations mentioned above) or out-of-body experiences. Hypnic jerks are also common, where the person jerks awake just before drifting off to sleep. This is thought to be caused by the brain misinterpreting sleep as “death” or the body shutting down, leading it to jolt the system back to life. 

Finally, an interesting psychological phenomenon is the Tetris effect, where people who have spent a prolonged time on one activity cannot stop seeing images and thinking about that activity in the hypnagogic state. This was seen in people who had played too much Tetris seeing coloured bricks before they went to sleep. Other common versions of the Tetris effect include chess boards and pieces, feeling waves after being at sea and seeing words and numbers after working on documents for a long time.

The combination of insight, creativity and sensory illusions leads to hypnagogia causing strange “experiences”. Ergo, hypnagogia is now thought to explain many supernatural experiences such as ghost sightings, UFO abductions, premonitions and visions.

Posted in Psychology & Medicine

Hedgehog’s Dilemma

Imagine two hedgehogs in the middle of winter. Even though they wish to huddle together to keep warm, they must keep distance to not become stabbed by the other hedgehog. There is no way they can avoid hurting each other without keeping their distance. Although both hedgehogs badly want to be close and intimate, they cannot. Therefore, the hedgehogs sacrifice the potential warmth for their own comfort.

Human relationships are just like the hedgehogs in the allegory. If a relationship is too close, the two people have a serious danger of hurting each other in one way or another. It is crucial to find the balance between keeping distance and having enough intimacy to have a good relationship, but much like the hedgehogs, this is a very difficult task. 

Some people may have the unfortunate experience of being pricked by another hedgehog and learn that getting too close hurts too much. These people try and keep their distance from other people and rely on their internal warmth to not freeze during the winter. This phenomenon is more pronounced in introverted people and clearly seen in those suffering from social anxiety.

This is the dilemma of the hedgehogs: should one sacrifice the warmth of companionship to avoid pain? Or should one overcome the potential pain to attain the intimacy that we all seek? Figuring out where the perfect balance lies and respecting each other’s personal space is quite possibly one of the most important factors in having a healthy relationship.

Posted in Psychology & Medicine

Phantom Limb Pain

In up to 80% cases of amputations, a strange phenomenon occurs where the amputee reports sensation or even severe pain where the limb has been amputated. It was noticed in field hospitals during wars when a soldier would wake up and ask someone to scratch his leg – which was no longer attached to his body. The sensation can be so powerful that victims actively believe that their phantom limb can interact with real objects. For example, there have been case reports of patients trying to pick up a cup with an amputated arm and becoming frustrated with their inability to.

Phantom limb pain may persist even after the amputee realises the limb is no longer there. The basis for phantom limb pain is a neurological system called the cortical homunculus. The cortical homunculus is a concept that the part of the brain responsible for sensation and movement is mapped out so that each part corresponds to a part of the body (see picture). For example, the top of the primary somatosensory and motor cortices (said parts of the brain) is responsible for foot sensation and movement while the side receives information from and sends signals to the face. It lets the brain construct an image of what the body looks like from sensory information it collates from various body parts. It is suggested that phantom limb pain is caused by a remapping of the cortical homunculus, fooling the brain to think that the limb is there even if it has been physically cut off. This also explains a similar condition called supernumerary phantom limb, where the brain believes there is an extra limb (e.g. a third arm).

As the homunculus concept is a recent idea, treatment options had not advanced much until the late 1990s. In 1998, a neuroscientist called Dr. Vilayanur S. Ramachandran devised a method called the mirror box treatment. He noticed that victims of phantom limb pain (PLP) had paralysis or pain in the limb just before the amputation (such as tightly gripping something before the arm got blown up by a mine), suggesting that PLP may be a form of learned paralysis. This means that the brain believes that the arm is still paralysed and any movement causes an uncomfortable sensation as the brain thinks the limb is contorted into a painful position. To fix this problem, Dr. Ramachandran invented a box with two holes, each going into a separate compartment. One compartment is for the good arm while the other has a mirror positioned on an angle to reflect the other arm (instead of seeing the stub they put in the hole). He would then instruct the patient to perform symmetric movements with both hands while looking at the reflected arm. For example, he would tell the patient to squeeze their “fists” tightly as possible and then let go. Through this procedure, the brain is retrained to let go of the perceived paralysis and pain as it is tricked in to thinking that the arm is healthy again. The mirror box therapy drastically improved the outcome and quality of life of PLP patients through the power of illusions.

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Posted in Psychology & Medicine

Alien Hand Syndrome

There is a very rare, disturbing and interesting medical condition called alien hand syndrome (AHS). An individual with this neurological disorder has full sensation in the rogue hand, but is unable to control its movements and does not feel that it is a part of their body. The hand becomes personified, as if it has a will of its own, and its owner will usually deny ownership of the limb.

Though AHS was first identified in 1908, it was not clearly defined until 1972. Depending on the cause of the injury, the movements may be random or purposeful, and may affect the dominant or non-dominant hand. The symptoms are brought on by an injury to the brain, such as head trauma, stroke, tumour, or infection. It can also be a side effect of a certain kind of brain surgery where the patient has the two hemispheres of the brain separated to relieve severe epilepsy.

If the AHS is caused by separation of the corpus callosum (the area of the brain that connects the two halves of the brain) by surgery or injury, the movements are usually complex purposeful behaviour, such as compulsive manipulation of tools, undoing buttons, or tearing clothes. For example, a right-handed person is left-hemisphere-dominant, thus their left hand (controlled by the right hemisphere) will become “alien”. Sometimes the sufferer is completely unaware of what the hand is doing until it is brought to his or her attention, or until they happen to see it themselves. 

Strangely, many of the alien hand’s actions are the complete opposite of what the person is doing with the other hand. For example, if they start packing a suitcase, the alien hand will unpack it. It is believed that one half of the brain (usually the right brain) is unaware of why the other hand is doing something (due to the lack of connection between the two hemispheres) and so proceeds to “correct” it. There are also reports of the alien hand attacking the patient by hitting them or even trying to strangle them in their sleep. 

There is currently no treatment for alien hand syndrome, but the symptoms can often be relieved by giving the rogue hand an object to manipulate, to keep it occupied. One patient whose alien hand had a compulsion of holding on to door handles or other objects to stop the man from walking was given a cane. The alien hand would grab on to the cane and not interfere with the patient’s walking.

There is currently no treatment for alien hand syndrome, but the symptoms can often be relieved by giving the rogue hand an object to manipulate to keep it occupied. One patient whose alien hand had a compulsion of holding on to door handles or other objects to stop the man from walking was given a cane. The alien hand would grab on to the cane and not interfere with the patient’s walking.

Although it is a distressing condition, some patients learn to live with the disease. For instance, when one patient’s alien hand kept throwing away the cigarette her dominant hand put in her mouth, she shrugged and said: “I guess ‘he’ doesn’t want me to smoke that”. Perhaps the alien hand is simply a way for the subconscious mind to physically act on the conscious mind.

Posted in Psychology & Medicine

Kuru

European explorers who visited the island of Papua New Guinea in the 1950’s noticed that the Fore tribe suffered from a strange disease. The patient would initially have headaches, joint pains and tremors. They then show signs of weakness and are unable to stand.  The shaking of limbs, a classic symptom of the disease, becomes progressively worse as the disease progresses (“kuru” is a Fore word for “to shake”). In the late stages, the patient shows other neurological symptoms such as uncontrollable laughter and emotional instability. By this point, their tremors and ataxia (lack of coordination) is so severe that they cannot sit without support. They may also suffer from inability to speak or swallow, become unresponsive to their surroundings, develop ulcers on the skin and become incontinent (cannot hold urine/faeces). Within 3 months to 2 years after the symptoms develop, the patient dies.

Kuru is exclusive to the Fore tribe and medical researchers were puzzled by the nature of this disease. It is incurable and takes more than 10 years to develop (from the time of infection). In 1961, Dr Michael Alpers discovered that kuru was spread due to a certain cultural behaviour within the tribe – cannibalism. The Fore tribe had a tradition of eating the corpse of a deceased tribe member at the funeral as to return their life force back in to the tribe. Of course, this involved the consumption of the brain as well.

It was discovered that kuru is caused by a strange pathogen known as a prion. Prions are misfolded pieces of proteins that cause disease by converting the body’s proteins into “wrong” proteins. These new prions then convert more proteins until the body is filled with deposits of such proteins. Prions mainly affect the brain and cause spongiform encephalopathy – meaning that the brain becomes sponge-like and full of holes. The most famous example of prion disease is mad cow disease.

After colonists took over Papua New Guinea, cannibalism was banned and kuru faded away. This was proof that cannibalism was what spread the prion from one victim to another. It was also discovered that women and children had a higher incidence as men would have priority in choosing what part of the body to eat first. As with lions, the men always chose muscles first and women and children would often finish the organs such as the brain. As prions are indestructible, it cannot be treated, cured or prevented (other than not eating brains). It also means that it transmits perfectly from a dead patient to an unsuspecting victim who is feasting on the infected brain.

A disease that causes the brain to disintegrate, causing limb shaking and inability to walk, spread by the ingestion of brains. Is it possible that zombies are caused by eating brains and not the other way around?

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Posted in Psychology & Medicine

Nirvana Fallacy

Humans have a tendency to think in a black-and-white manner, leading us to fall into the trap of the Nirvana fallacy. This is when one compares the real world to some perfect yet unrealistic alternative, causing reality to pale in comparison. Thus, it causes us to believe that many things are not worth doing as they are insignificant compared to this alternative.

For instance, the notion of the drop in the ocean means that we tend not to do altruistic things as we believe that it will not make much of a difference in fixing poverty or cure the world of cancer. Not only does the fallacy apply to how we see the world, but it affects day-to-day life too. People are so afraid of not being able to achieve an ideal, perfect future so ironically they do nothing. This is a major reason procrastination happens, as the person believes that if they do something now, it will be inefficient. They then plan for a perfect opportunity to start doing work, and a vicious cycle begins. Thanks to this way of thinking, people often miss out on a great job opportunity or a lovely girl or a chance to change their life just because it was not perfect and did not live up to their expectations.

In fact, people often fail to see the small steps and only see the big picture. So if someone tries to make an improvement (e.g. going on a diet), others will ridicule that person by saying that going to the gym every week is not going to turn you into an Adonis, ergo it is pointless.

The Nirvana fallacy is also useful in debates. One can create a false dichotomy (that is, a black-and-white argument) and compare someone’s argument to an unrealistic argument. When someone makes a suggestion, you can attack it by pointing out one flaw and show how it is clearly not a perfect solution (even better if you provide an example of the argument failing). This will automatically disintegrate their argument. For example, if someone proposes a new idea, you may point out how someone may abuse the new system or provide a case when a similar idea failed. However, be warned that this method can easily be rebutted with common sense, so one must use it in a convincing way and distract the audience from the fact that it is absolutely ridiculous.

(The Garden of Earthly Delights by Hieronymus Bosch, click for larger image)

Posted in Psychology & Medicine

Munchausen’s Syndrome

Some people are known to overreact regarding their health, such as a hypochondriac thinking that she has kidney failure because her urine looks slightly frothier. However, some people far surpass the level of hypochondrias to the level of psychiatric disease.
Münchausen’s syndrome patients are known to exaggerate or create symptoms so that the doctor would pay attention to them. When the doctor investigates, treats and sympathises with the patient they gain satisfaction from all the attention they are receiving.
Although this may sound like hypochondrias, Münchausen’s is far more serious.

A Münchausen’s patients are known to cause symptoms just to get attention from others. For example, a common manoeuvre used is the injection of insulin to induce a hypoglycaemic seizure. When their symptoms are “treated”, the patient will most likely invent another factitious disease to be treated for a longer time. They will also seek out many different doctors when the attending doctor catches on to their act. In fact, a Münchausen’s patient will do almost anything to prolong medical care, even accepting unnecessary and risky procedures such as surgeries.

The key difference between Münchausen’s syndrome and hypochondriasis is that the patient is aware that they are not actually sick (hypochondriacs actually believe they are sick). The fundamental basis for Münchausen’s syndrome is the desire for attention. Thus, the main risk factor for developing Münchausen’s is childhood experience of seeing someone close (typically a family member) suffering a debilitating disease. For example, if a girl sees her sister suffering from leukaemia and receiving all the attention of everyone around her, she may develop feelings of jealousy and later try to duplicate the scenario. As a patient, the person feels safe and comfortable and this feeds their addiction to medical care.

As Münchausen’s patients are very proficient liars and act completely like an actual patient, doctors must rule out any diseases before suspecting that their patients have a psychiatric problem. However, some signs such as the patient being overly keen on receiving procedures such as biopsies or continuously developing random symptoms may indicate Münchausen’s.

Interestingly, a similar condition called Münchausen’s syndrome by proxy also exists, where a caregiver (e.g. mother) convinces a doctor that the person they are caring for (e.g. child) are sick. Unfortunately, as these patients actually cause illness in the child, it is considered a form of child abuse. Common “symptoms” include: growth problems, asthma, allergies, vomiting, diarrhoea, seizures and infections. This may lead to the child developing Münchausen’s syndrome in the future.