Tag: experiment

Posted in Psychology & Medicine

Rat Park

Posted on by Jinavie

In the mid-20th century, rat models were used by psychologists to study the science of drug addiction. Rats would be placed into cages, connected to a pump that would deliver a dose of morphine when a switch was pressed. These rats would press the switch to get more “hits”, with some rats pressing the button in preference to food and water, eventually dying from dehydration.

In the 1970’s, Professor Bruce Alexander questioned whether this was an accurate description of the nature of drug addiction in humans. He posited that given that rats are social animals, placing them in isolation would put them in an environment where the drugs were the only “escape”. To study this, his team designed a large enclosure that they nicknamed “Rat Park”.

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Rat Park was designed to be a utopia for rats. It was 200 times the size of a standard cage, filled with comfortable cedar shaving floors, plenty of nesting areas, toys and abundant food. Most importantly, the enclosure had all 16 rats living in the same enclosure, so that they could interact with each other. The control group were placed individually in 16 separate isolated cages.

The researchers gave the rats a choice of two fluids to drink from – water and water laced with morphine. Although the rats initially stayed away from the morphine due to the bitterness, they eventually started drinking from it when they realised the euphoric sensation they got from drinking it. Interestingly, rats in cages would follow the traditionally predicted path of drinking more and more morphine, becoming addicted. However, rats living in Rat Park would barely touch the morphine water. Even when the morphine was sweetened with sugar, the rats would still not drink much of it.

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Through rigorous experiments, the researchers deduced that the Rat Park residents preferred social interaction over the drug-induced haze from drinking morphine. Rats under the effects of morphine were less able to socialise and in an environment with adequate social stimulus, this was a good enough reason to avoid drugs.

In a different experiment, Professor Alexander’s team put rats already dependent on morphine into Rat Park. They found that despite withdrawal symptoms, rats would prefer staying away from morphine and would attempt to socialise.

Although it remains controversial, Alexander’s research into Rat Park offered new insights into the study of drug addiction. It raised the question of whether drug addiction was purely an issue of biochemistry and how much effect our social environment has on our life choices.

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Posted in Science & Nature

Hammer And Feather

Posted on by Jinavie

What would happen if you dropped a 1kg ball and a 10kg ball at the same time from a high building? Most people would think that the 10kg ball would obviously fall faster and thus hit the ground faster, but the truth is they would fall at exactly the same time. The reason for this is that the force that accelerates a falling object is gravity, which on Earth is constant at 9.81ms-2. This means that no matter how heavy the object is, they will always accelerate by 9.81 metres per second per second. This was hypothesised by Galileo Galilei, who came up with the thought experiment of dropping two balls of different mass from the Leaning Tower of Pisa (there is debate as to whether he actually performed the experiment). The theory was later solidified by a certain Isaac Newton, who devised the laws of universal gravitation and the three laws of motion.

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However, if the two balls were dropped from an extremely high place, they may land at different times as mass affects the terminal velocity – when the force of gravity equals the force of drag caused by air resistance, leading to a constant velocity. A heavier object will keep accelerating to a greater velocity than a lighter object, which would have reached terminal velocity before the heavier object.

One place where this will not happen is in a vacuum where there is no drag force. To prove that the hypothesis that two objects of different masses will fall at the same time in the absence of air resistance, Commander David Scott of the Apollo 15 moon mission took a hammer and a feather with him. Once he landed on the moon, he dropped the hammer and feather in front of a live camera, showing that the two landed at exactly the same time. He thus proved that Galileo’s conclusion from two hundred years ago was in fact correct.

Posted in Psychology & Medicine

Overpopulation

Posted on by Jinavie

In 1972, John B. Calhoun designed a very specific mice cage called Universe 25, also known as the Mortality-Inhibiting Environment for Mice. Universe 25 was designed as a practical utopia for mice. It was constantly replenished with food and water, each wall had an intricate grid of nesting boxes connected by mesh tunnels and stairwells (like an apartment) and the cage was cleaned periodically. There were no predators, the temperature was set at a comfortable level and all mice resident were disease-free. In all ways, Universe 25 was an idyllic home for the mice.

Calhoun’s aim of this experiment was the same as the countless experiments before Universe 25: to see the effects of abundance on a population, and the consequences of that. Biologically speaking, a population only grows to the point that the environment can sustain it and then plateaus. So if the environment is completely abundant, the population will grow and grow without limitations (other than space). Thus, Calhoun’s main focus was overpopulation in societies. What did he find?

At the start of the experiment, four breeding pairs of mice were introduced to Universe 25. They began reproducing after 104 days of familiarisation and the population increased exponentially. The mice flourished in the prosperous environment. Around day 315, population growth slowed. By this stage, the mice population had grown to over 600, which made Universe 25 very crowded. Although there were still plenty of resources, the problem of overpopulation still remained. As the population grew and space became limited, male mice found it too difficult to defend their territory and eventually gave up doing so. The mice began losing their ability to form social bonds and these mice (“failures”) began congregating at the centre of the cage. This group of mice gave up on all normal social behaviour, leading to constant violence. The violence soon spread throughout the cage, with the mice society descending into chaos. The females, stressed and confused by the violence, attacked and cannibalised their own young, after which they retreated to the highest nest boxes where they isolated themselves. Certain males (termed “the beautiful ones” by Calhoun) did not show violence or any interest in females, choosing only to eat, sleep and groom themselves, wrapped in narcissistic introspection. Because of these two isolated groups, procreation slumped and population growth slowed. Elsewhere, in the “inner city” group at the middle of the cage, cannibalism, pansexualism and violence became common. The entire society had collapsed.

On day 560, the population ceased to grow at a peak population of 2200. After this, the number of pregnancies dwindled to nothing and no young survived past infancy. Adult mice were also affected, with mortality rates skyrocketing at all ages and increased rates of diseases. It was clear that the population was headed towards extinction. Even after the population dwindled down to a much more sustainable number, the mice were incapable of (or chose not to) reproducing to regenerate the population. Not only did mice society die, but the mice themselves met a grim fate as well.

This result was repeated in all of Calhoun’s experiments, conclusively showing that overpopulation leads to the demise of a society. Calhoun described this as “crowding into the behavioural sink”. He explained that the mice served as a warning to what human societies are headed towards if we do not solve the problem of overpopulation. We can already see the effect overpopulation has on societies. It is a known fact that people living in the inner areas of a city are more prone to poverty, crime, violence and a lower quality of life. However, Calhoun was not a nihilist. Instead of saying “humanity is doomed”, he explored different ways of resolving the problem. The most effective idea he came up with was space colonisation.

Posted in History & Literature

Mary Celeste

Posted on by Jinavie

In 1872, a ship by the name of Mary Celeste was spotted off the Azores in the Atlantic Ocean – completely intact and undisturbed aside from its missing crew. Not a single person, alive or dead, could be found, despite everyone’s personal belongings still sitting undisturbed where they had been left. Even little things such as valuables and piano music were right where they should have been. It was as if its crew had simply evaporated. There were no signs of a struggle and no cargo was missing. To this day, the case of the disappearing crew of the merchant ship Mary Celeste is one of the most famous maritime mysteries in history.

So what happened to the ship’s crew? Historians have been trying to figure out their fate for decades, but the question was finally solved by scientists. One fact that is known about the Mary Celeste is that of its cargo of 1701 barrels of alcohol, 9 were empty. Although an obvious answer is that the sailors went overboard with a party, the truth is even more spectacular. In 2006, Dr. Andrea Sella, a professor of chemistry at University College London, created a replica of the Mary Celeste’s hold to find out how to create an explosion without leaving a trace of fire. He simulated a leak of the ship’s nine barrels of alcohol and found that once the vapour was ignited, say by a pipe or a spark, it created a pressure-wave type of explosion. There was a spectacular wave of flame but, behind it was relatively cool air. No soot was left behind and there was no burning or scorching.

Ergo, the mystery of the Mary Celeste is most likely as follows: there was a leak of the alcohol, the vapour of which fuelled a massive ghost explosion that swept through the ship. The sailors, completely unscathed but utterly horrified, would have piled into the ship’s lifeboat without any useful things like food or water, eventually sinking or dying of thirst and exposure. The Mary Celeste would have still looked perfectly fine as it drifted the vast ocean, all by itself.

Posted in Psychology & Medicine

Doorway Amnesia

Posted on by Jinavie

Have you ever experienced the curious phenomenon where you walk into the kitchen and completely forget why you came there? Or why you stepped out of the house? Almost everyone is struck with this bizarre amnesia at some point in their lives. But why does it happen? Do Men in Black come in and wipe your memory because there was an alien in the room or something? The answer lies in the doors.

It has been scientifically proven that doorways have a magical property of causing memory loss. To be exact, doors do not cause amnesia, but the physical act of passing through a doorway causes the brain to lose memories. The reason for the phenomenon is this. The human brain stores information in a very unique way where it compartmentalises information by physical location. Because of this “filing system”, the thought “I really want cake from the kitchen” that you had in the living room is difficult to access when you are in the kitchen. By crossing a doorway, the brain recognises that the physical location has changed and opens a different “folder”, metaphorically speaking. This system allows for smooth mental functioning usually as it lessens the load on the brain, but also creates confusing situations where you just stand in front of the door, questioning whether you are losing your memory.

In an experiment in France, it was found that when students were told to memorise certain objects and then walk into another room, they had much worse recollection of the objects compared to the control group (students who walked the same distance but not through a door). It was even found that a person did not even have to physically walk through a door to lose their memory. When students were made to repeat the experiment in a virtual setting (i.e. moving a computer character through a door in a game), the same thing happened. The effect was so powerful that the researchers dubbed doorways event erasers.

Although it seems like an inconvenient system, the brain’s special way of compartmentalising information according to physical location can be used to harness the power of complete memory. This is done by using the method of loci, also called the memory palace. This is a mnemonic device first devised by ancient Romans to help memorise a large amount of information. To use the memory palace, you must first visualise a certain location – one that you are familiar enough with to recall with great detail. This may be your room, house, the street you live on, or even a fictional palace. The object of the memory palace is to convert a piece of information into an item which you can place in a certain location in the palace. For example, if you have to memorise a shopping list, you can conjure a mental shelf in your mental palace and put all the items in the shelf. To enhance this effect, make the image as bizarre and fancy as possible, as the mind is prone to remembering weird things more (e.g. a massive apple with eyes and a mouth is more memorable than a normal apple). Once your memory palace is complete, you can take a “mental walk” through the palace, go to the room where the memory you need is stored, and just browse the contents to recall the information. With practice and a vivid imagination, this is an infallible method of remembering anything you want, for as long as you want.

Posted in Psychology & Medicine

Learned Helplessness

Posted on by Jinavie

The following is an incidental finding from an experiment studying conditioning in dogs. In stage 1, a dog was tied on a leash in a room with electrified floors to prevent it from running away and was shocked for a day. Next, the dog from stage 1 and another dog were left in the same room without any leashes, leaving the door opened so that they could run away when they were shocked. Although the dog that did not pass stage 1 (fresh dog) immediately ran to the next room, the dog from stage 1 just helplessly lay down on the floor, receiving the electric shock. In stage 3, the same dog from stage 1 was taught that going to the next room prevents it from getting shocked. However, even after learning this, the dog refused to move and stayed in the room and accepted the shock. It had learned helplessness.

Everyone has depressing moments in their lives, but when these repeat over time it can cause you to feel that life is an inescapable pit of despair. You will learn a sense of helplessness that no matter what you do, the result will be failure and disappointment. But the moment you accept this helplessness, the nightmarish fate that you loathe so much becomes reality. There is no such thing as fate or destiny. If you do not like the fate given to you, free yourself the restraints of life, break away from the fetters and pioneer a new future for yourself. 

Posted in Psychology & Medicine

Pleasure Centre

Posted on by Jinavie

During the 1950’s when the field of neuroscience was making many research breakthroughs, a fascinating fact was discovered. Scientists had located the specific part of the brain responsible for feeling pleasure. In 1954, two Canadian neuroscientists named James Olds and Peter Milner were undertaking research to find the association between electrical stimulation of the brain and sensation in rodents. During their research, they found that if they stimulated a certain part of the brain, the rats would interpret the signal as pleasure. Based on this, they inserted electrodes into the rats’ limbic system (the part responsible for emotions) and connected it to a lever in the cage. Thus, they had devised a device that allowed the rat to feel pleasure by stimulating its own brain with the press of a lever. The results were astounding. The rat furiously pumped at the lever, forgetting to eat or sleep, until it ultimately died of exhaustion (over 26 hours, the rat pressed the lever 50,000 times).

Pleasure is not the same as happiness. Happiness awards us with satisfaction and contentment, but pleasure only brings greed, obsession and addiction. Pleasure was originally a mechanism devised to reward behaviour that aided survival (such as mating and eating), but addictive things like alcohol, smoking and drugs ruin your life and any chance at happiness instead of helping you survive.

The foolish run around to seek temporary pleasure while the wise seek permanent happiness.

Posted in Psychology & Medicine

Time Perception

Posted on by Jinavie

What exactly is the present? The present is the middle point between the past and future, the world that we experience and perceive on a real-time basis. But would you believe it if the world you perceive is not the true “present”? To experience the world, we use our five senses. The brain collates all these sensory information and processes it to construct “the present”. This process takes about 80 milliseconds. Ergo, the world we experience is actually the world as it was 80 milliseconds ago. For a similar phenomenon, consider the stars. The stars we observe are not what they look like now, but what the stars looked liked when they emitted the light that we see. Thus, the star you are looking at may not even exist anymore.

But 80 milliseconds is a very short time; surely it has no impact on our everyday life? To prove that this delay has a critical impact on our understanding of cause and effect, neuroscientists designed the following experiment. The researchers would ask the participant to press a button that caused a light to blink after a short delay. After about ten tries, the participants reported that the delay had disappeared and the light flashed immediately after they pressed the button. This was due to their brain editing out the time delay and directly connecting the cause (button) and the effect (flash). But a much more peculiar phenomenon was seen when the researches removed the delay between the button press and the flash. Participants reported that they saw the light flash before they even pressed the button. The participant’s brain had become so used to the editing process that it was confusing the order of the cause and the effect.

The brain’s time-editing ability can be seen in the following simple experiment. If you touch your nose and toe at the same time, logic dictates that as the toe is further from your brain, the signal will have to travel further and it will be felt later. But in reality, you feel both at the exact same time. This is because your brain uses a map of the body to edit the relative time the signal takes to reach the brain to better construct a “real-time present”.

Posted in Science & Nature

Pitch Drop Experiment

Posted on by Jinavie

When you refine crude oil, you get a black by-product called pitch, which looks like a sticky solid. However, two scientists of University of Queensland, Professors Thomas Parnell and John Mainstone, designed an experiment to prove that pitch is actually a liquid. They simply poured pitch into a funnel and placed a beaker under it to see if it will drip. Eight years after the experiment started, the first drop fell and it was found that pitch is a (extremely viscous) liquid. For the second drop to fall, another nine years had to pass, and by the time the third drop fell another nine years later, Professor Thomas Parnell had already passed away. This experiment began in 1927 and is still ongoing (the longest experiment in history) and so far eight drops of tar have fallen. The experiment is now recorded via a webcam for better observation, but in 2000, the eighth drop was never recorded due to a very untimely camera malfunction.

Posted in Psychology & Medicine

Spinach

Posted on by Jinavie

Spinach is a vegetable that is excellent for your health as it is rich in nutrients such as vitamins and minerals. If you ask someone the first two things that come to mind regarding spinach, they will most likely reply Popeye and iron. Popeye is a cartoon that began airing in the 1930’s and every child knows that the man gains superhuman powers from eating a can of spinach. In fact, after Popeye began airing, US consumption of spinach grew 33%. Most people believe that Popeye gains powers due to spinach having a high iron content. Thus, adults always tell children that if they want to be as strong as Popeye, they must eat their spinach.

Unfortunately, eating spinach does not make you as strong as Popeye. In fact, it is not even related to iron either. Firstly, the reason why Popeye eats spinach was because the producers wanted to advertise the high vitamin A content in spinach. Furthermore, spinach does not have a high iron content. The spinach iron myth originated from a German scientist named Emil von Wolff. In 1870, von Wolff was analysing the nutrition contents of different foods when he, from severe fatigue, accidentally misplaced a decimal point while recording the iron content of spinach. This led to spinach being known to have ten times the amount iron it actually has (to the level of red meat).

One problem with this is that this story is not true either. There are no detailed records of von Wolff’s experiments and no one knows if he misplaced a decimal point or not. The myth most likely originates from a 1980 article in The British Medical Journal that first brought up the story. Does that mean spinach is actually is a good source of iron? Wrong. Vegetarians often claim that spinach has iron levels close to red meat, but there is something about iron that they do not know. Many plants have a high iron content (it is found in chlorophyll which is used for photosynthesis), but this is mostly non-heme iron. There are two types of iron the human body can absorb: heme and non-heme. Heme iron can be used directly after absorption whereas non-heme iron needs to be metabolised by the liver to be usable. This takes a long time and is inefficient meaning it is far more effective to eat foods rich in heme iron. Plant iron is all non-heme iron while 40% of iron in red meat is heme iron, meaning it is a much better source of iron. Furthermore, spinach has a high oxalate content, which is an iron absorption inhibiting agent, making what little usable iron it has unabsorbable. 

In short, it is true that spinach has “iron” but as we cannot absorb it or use it, it practically has no iron content. But if you tell this to your parents and refuse to eat spinach, you may get into a lot of trouble.