Tag: brain

Posted in Science & Nature

Vision

Posted on by Jinavie

Consider this: if you see something that is not there, or not see something correctly, is that due to a problem in your eyes or your brain? An interesting anatomical fact is that the eyes are part of the brain. They originally evolved from the brain and drifted further and further forwards, connected to the brain by the optic nerves. If you lift a brain out from the skull, the eyes would be pulled backwards too. But technically speaking, eyes are distinct organs by themselves that have merely originated from a portion of the brain. It does not think or make decisions by itself. Just like a camera, an eye records things as it sees it and transmits it to the brain via the optic nerve via electrical signals. The brain then processes the signals in the occipital lobe, located at the back of the head (this is why you “see stars” when you bang the back of your head).

This means that vision can be altered anywhere along the pathway. If you have cataracts, where the lens of the eye becomes clouded, you lose portions of your visual field. If you have a large pituitary gland tumour, it presses on the optic nerve and causes double vision (diplopia) or vision loss. If you have a stroke in the occipital lobe, you can lose your vision. The brain’s role in producing vision can easily be demonstrated in the form of optical illusions. The eye merely records and transmits what it sees, but the brain becomes confused by what information it receives and tries to make sense of it. In the process, we experience bizarre illusions such as static images moving by themselves.

Because of this intricate pathway, some pathologies present with fascinating symptoms. A condition called Anton’s blindness (or Anton-Babinski syndrome) causes a patient to “see” despite being blind. Patients with Anton’s blindness are adamant that they can see perfectly clearly, and will even describe what they are seeing. However, what they “see” is completely different to what the object actually looks like. For example, if the patient looked at a blonde woman wearing a yellow blouse and a red skirt, they may describe her as a brunette woman wearing a blue shirt and black jeans.

The reason for their blindness is that their occipital lobe was damaged (usually by a stroke), leading to an inability to process the information from the eyes. Although the eyes are pristine and record what they see in perfect detail, the brain is incapable of interpreting the signals. The brain then goes on to confabulate, where the brain fills the gap by conjuring up false information. This makes Anton’s blindness quite hard to pick up on as the patient will not complain of it. It is only found when someone pays close attention to the patient and notices subtle cues like the patient bumping into furniture or talking in the direction where they think a person is at (even after they move). Ergo, the patient adamantly believes that they can see as their brain thinks it is seeing things (even though it is not receiving the information from the eyes properly).

Seeing is not believing. You see what you believe.

Posted in Psychology & Medicine

Berry Aneurysm

Posted on by Jinavie

Stroke is a disease often associated with the elderly, but this is not necessarily true. As much as 5% of the population carry a ticking time bomb in their brain, known as a berry aneurysm. An aneurysm is a weakening of the arterial wall, causing a localised ballooning of the vessel. A berry aneurysm is a common type of aneurysm where the ballooning resembles a berry. What is most troubling is that a large proportion of these aneurysms can present very early (usually congenital, meaning you are born with it), with one research suggesting that 1.3% of the population in the age group of 20 to 39 has a berry aneurysm. If this berry aneurysm was to burst, no matter how young and fit you are, you will bleed into the area around your brain (subarachnoid haemorrhage), suddenly develop a severe, crippling headache (“thunderclap headache”), become confused, show signs of stroke such as speech or movement problems, or simply drop dead.

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Fortunately, only 10% of people carrying a berry aneurysm suffer a ruptured aneurysm and subsequent brain bleed. The other 90% will carry on living their lives, without ever knowing that they had a time bomb in their brain.

Certain factors make the risk of the aneurysm bursting go up, such as high blood pressure, which can be caused by a stressful lifestyle or smoking. But in some cases, as explained above, even a healthy teenager could suddenly drop to the ground with a massive brain haemorrhage.

Berry aneurysms are only one of many ways death could strike unnoticed, no matter how young you may be. You could live a long and healthy life and die peacefully in your sleep when you are 90 years old, or you may have a stroke and drop dead in a few minutes’ time. For all you know, a bus might run you over tomorrow, with no warning whatsoever. Ergo, youth is not an excuse to waste the day you are given. You do not have to achieve something great, or be productive, but at least spend your day knowing that you are doing everything in your power to make yourself happy, without harming your health, your future or other people.

Carpe diem. Seize the day.

Posted in Psychology & Medicine

Child Prodigy

Posted on by Jinavie

At the age of 6, Wolfgang Amadeus Mozart toured Europe to astound audiences with his mastery of the violin, organ and keyboard. At the age of 11, Judit Polgár defeated a Grandmaster in chess, later becoming a Grandmaster herself at the age of 15. By the time he finished elementary school, Saul Kripke had taught himself ancient Hebrew, finished the works of Shakespeare and mastered the works of Descartes and complex mathematical problems.

Each of these people is considered a child prodigy – person who develops and shows extreme talent in a skill at a level far beyond the norm for their age. The term wunderkind (German for “wonder child”) is also used. For some unexplained reason, these people are far beyond the average level of children at their age in terms of intelligence or a certain talent.

Prodigies are actually a subset of a condition known as precocity, where a young child shows unusually early development or maturity, especially in mental aptitude. For example, a German child called Christian Friedrich Heinecken is known to have talked within a few hours after his birth, learnt the key events of the first five books of the Torah within a year, mastered the Bible at age 2 and had a working knowledge of universal history and geography, Latin and French at age 3. Unfortunately, he was struck ill at the age of 4, and shortly after predicting his death, passed away. Heinecken’s case is an extreme example of precocity, but nonetheless most precocious children show at least an outstandingly advanced level of mental maturity compared to other children. Along with prodigies, savants and children with extraordinarily high IQ (over 160) are also considered precocious.

Although precocious children enjoy their extreme talent (for which they usually have deep passion for) and may even become famous for it like Mozart, they are almost always at risk of certain problems. One common issue is that they tend to be placed on pedestals as people constantly praise their ability. This can quickly evolve into narcissism, setting a major expectation that the child battles with throughout his or her life. Children with advanced intellect are often unable to fit in to society as they are far more intelligent than their peers. Not only do other children shy away from them, but they feel too bored and unstimulated by other children and choose to alienate themselves. Furthermore, although they may have the intelligence and maturity to comprehend philosophical concepts, they still have the emotions of a child, meaning they are tormented by the dissonance between the rational mind and their emotions. All of these factors combined lead to a great increase in risk of depression in precocious children.

Essentially, the main conundrum for child prodigies is trying to balance their amazing talent with a happy life in a “normal” society. This could be achieved by parents keeping things real and not placing excessive expectations on the child, and giving the child a way to vent their genius in some way. For example, chess has been a classic way of keeping children with high intellect engaged. Having this kind of vent allows the child to still engage with other members of his or her society (other children), while honing their great skills for an even brighter future. The child must stay engaged and passionately practise and advance their skill so that they do not stay in a perpetual rut all their life.

With great power, comes great responsibility.

Posted in Psychology & Medicine

Phineas Gage

Posted on by Jinavie

On September 13, 1848, a 25-year-old foreman named Phineas P. Gage was working on a railroad with his work team. In an unfortunate turn of events, as he was using a tamping iron (large iron rod with a pointed end, measuring 3 feet 7 inches in length and 1.25 inches in diameter) to pack gunpowder into a hole, the powder detonated. The forceful explosion drove the metal pole skyward through Gage’s left cheek, ripped into his brain and exited through his skull, landing dozens of metres away. His workmates rushed to Gage’s assistance (who they presumed to be dead at the time of the accident), and to their surprise, found that he was still alive.

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In fact, Phineas Gage spoke within a few minutes of the incident, walked without assistance and returned to his lodging in town without much difficulty – albeit with two gaping holes in his head, oozing blood and brain everywhere. He was immediately seen by a physician who remarked at his survival. In fact, it is reported that he was well enough to say: “Here is business enough for you” to the doctor. Another physician named Dr John Harlow took over the case, tended to the wound, fixed up the hole and recorded that he had no immediate neurological, cognitive or life-threatening symptoms.

By November, he was stable and strong enough to return to his home, along with the rod that nearly killed him. His family and friends welcomed him back and did not notice anything other than the scar left by the rod and the fact that his left eye was closed. But this was when things started to get interesting.

Over the following few months, Gage’s friends found him “no longer Gage”, stating that he was behaving very differently to the man who he was before the accident. Dr Harlow wrote that the balance between his “intellectual faculties and animal propensities” had seemingly been destroyed. Gage became more aggressive, inattentive, unable to keep a job, verbally abusive and sexually disinhibited. He would frequently swear using the most offensive profanities and would be as sexually suggestive as a March hare. How did the iron rod cause such a dramatic change in Gage’s personality?

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Phineas Gage would go on to be one of the most famous patient case histories in the history of modern medicine. His case was the first to suggest some sort of link between the brain and personalities. Neurologists noted that the trauma and subsequent infection destroyed much of Gage’s left frontal lobe – the part of the brain that we now attribute to a person’s logical thinking, personality and executive functions. It is in essence the “seat of the mind”. Ergo, Gage’s loss of one of his frontal lobes meant that his control of bodily functions, movement and other important brain functions like memory were undisturbed, while his “higher thinking” was essentially destroyed (he was essentially lobotomised). This explains Dr Harlow’s observation of his “animal propensities”.

Thanks to this case, a great discussion was sparked and the idea that different parts of the brain govern different aspects of the mind was conceived. We are now able to localise almost exactly where the language area is, what part controls movement and how a certain piece of the brain converts short-term memory into long-term memory.

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Posted in Psychology & Medicine

Agonal Breathing

Posted on by Jinavie

When a person is on the verge of death, they may show a very strange pattern of breathing. They will begin gasping for breath, take deep laboured breaths, begin to make strange noises and possibly have some muscle jerks (which may look like a seizure). The breathing makes it look as if the person is taking a deep breath and sighing, while gasping every now and then irregularly. This is called agonal breathing and it is most likely caused by an oxygen-starved brain sending weak signals to try kick up the respiratory drive for more oxygen.

Agonal breathing is not uncommon in cases of cardiac arrest. It is important to note that agonal breathing is not an efficient form of breathing and thus it cannot be said that the victim is “breathing” when this occurs. Because it looks like the patient is taking deep breaths, bystanders may be fooled into thinking that they have been resuscitated and have begun breathing again. But this is not the case and the patient is still clinically dead. Ergo, one should not stop CPR even if the patient begins taking deep breaths and sighs. The presence of agonal breaths usually indicate a better outcome for the patient.

(Link to video examples of what agonal breathing looks like: http://emsbasics.com/2011/04/21/what-it-looks-like-agonal-respirations/)

Posted in Psychology & Medicine

Viscera: Brain

Posted on by Jinavie

(Learn more about the organs of the human bodies in other posts in the Viscera series here: https://jineralknowledge.com/tag/viscera/?order=asc)

(NB: I have written MANY ARK posts about the brain and all the delightful ways it screws up. Some of them are probably the most interesting posts on my blog. Please click the hyperlinks to check out the various related articles! 😀 Alternatively, here’s a convenient list: https://jineralknowledge.com/tag/brain/?order=asc)

Among the many organs of the human body, no organ comes close to the magnificent complexity that is the brain. The brain acts as the command centre of the body. It receives massive amounts of information through the various senses, processes it and sends out electrical signals to control how the body operates. Not only does it control “basic” functions such as movement of muscles, controlling organ functions and regulating homeostasis, it is also responsible for the so-called “higher functions” such as consciousness, emotions and cognition. It is the true seat of the mind and soul.

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The brain is the only major visceral organ not located in the trunk (body). It is enclosed in the cranium of the skull, which acts as a protective casing. Because it is a closed box, even a small increase in volume (such as due to a bleed or a tumour) can cause extreme pressures to build, causing severe problems. The entire brain and spinal cord are bathed in a fluid called cerebrospinal fluid (CSF), all enclosed by a sheath made of three layers (dura, arachnoid and pia maters). The brain sends out nerves to the rest of the body, which act as electrical wiring transmitting signals. These include the cranial nerves and the spinal cord, which leaves the bottom of the skull down the spine. The spinal cord branches off into many nerves that supply every nook and cranny of the body. The brain itself is made up of two large hemispheres, which are connected by a bridge called the corpus callosum. Despite popular belief, the actions of the two hemispheres are much more complicated than “analytical vs. creative”. The brain also encompasses the cerebellum (the small stripey structure at the back), which controls coordination and speech articulation, and the brainstem, which is involved in autonomic control of life-sustaining functions such as breathing, and also the source of the cranial nerves.

In the last century, scientists have learned that specific parts of the brain play a specific role. This thought started with the field of phrenology, where small areas of the brain were mapped to a certain mental faculty, such as love, wit or destructiveness. Although this turned out to be complete hokum, the idea stayed and we now know the actual functions of each part of the brain. The brain is broadly divided into four lobes: frontal, parietal, temporal and occipital. The frontal lobe is the domain of thought, personality, motor function and other higher functions. The parietal lobe is related to spatial awareness and sensory functions (such as touch). The temporal lobe is linked to hearing, comprehension of language and storing new memories. The occipital lobe is primarily associated with vision. The brain can then be subdivided into more focussed areas, such as Broca’s area that governs speech and Wernicke’s area that governs listening. It should be noted that the four lobes only describe areas on the surface of the brain (cerebral cortex) where the higher functions belong. The inside of the brain is just as complicated and has many different parts, such as the hypothalamus that is involved in homeostasis, and the hippocampus that converts short-term memories into long-term memories.

How does a lump of cells weighing around 1.5kg produce such wondrous abilities such as philosophical thought, deduction, emotions and calculation? The truth is that we still do not know how the brain functions exactly. However, we know that the brain is composed of a large number of neurons (nerve cells) – about 100 billion of them. These neurons connect to one another via a synapse, which is a gap between two nerve cells where neurotransmitters travel to and fro (allowing electrical impulses to jump from one neuron to another). Using these connections, neurons form an unbelievably intricate and complex network of electrical activity. Because one neuron can connect to many more others, the number of synapses is estimated to be around 100~1000 trillion – significantly more powerful compared to any computer in the world. The number of synapses directly correlates to intelligence and it seems intellectual activities such as reading a book increases the number of synapses in the brain. We have yet to understand exactly how the brain uses this incredible computational power to produce cognition and self-awareness.

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(Video of neuronal activities in a zebrafish brain)

Because the brain uses electrical impulses for most of its functions, a common abnormality that is seen with the brain is when the electrical activity becomes disorganised and out of control – a seizure. This abnormal electrical activity may be due to a focal problem such as a tumour, or a generalised misfiring of neurons or altered regulation of electrical activity. When a seizure happens, the disorganised activity results in the brain not being able to function normally. For example, the most common consequence is a fit (tonic-clonic seizure) where every muscle spasms out of control, because the muscles are overloaded with chaotic signals. Focal seizures can cause fascinating symptoms depending on the location, such as temporal lobe seizures causing religious visions (hallucination). This also disrupts consciousness, which is why most epilepsy patients do not remember the event.

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Posted in Life & Happiness

Life Review

Posted on by Jinavie

They say that when you face your mortality, your entire life flashes before your eyes like a sped-up autobiographical film. This tends to happen in situation where a person feels they are in danger of imminent death, such as moments before a car crash. Reports say that the event typically lasts anywhere between less than a second to few seconds, and what they perceive as major life events flash before their eyes, usually in chronological order. However, reports are very subjective and variable.

This phenomenon sounds very clichéd, but it has been widely reported throughout time and space. Over 8 million people in the United States of America stated that they experienced this “life review” in a near-death experience, with countless records in historical texts, reaching far back as at least 1795 in a letter by Rear-Admiral Sir Francis Beaufort. It is fascinating to see that there is even a set name or phrase for this phenomenon deeply ingrained in various languages, such as English, German, French, Dutch, Russian, Persian, Arabian and Korean, suggesting that the phenomenon is widespread and common.

There is no strong evidence for why this phenomenon occurs, but there is one theory that is persuading. The brain is always subconsciously referring to past experiences and knowledge to apply to the present to help solve a problem. It has been suggested that when you are at the brink of death, the brain frantically searches through everything in an attempt to save you from demise. This is a rather messy process as the brain does not routinely encounter such near-death experiences and does not have much information to refer to immediately. In this process, it brings up every memory that you thought you had forgotten, which you see as a montage flashing before your eyes. For example, a man who was attacked by a great white shark reported that out of nowhere, he recalled his son watching a documentary on sharks and remembered that putting your hands down a shark’s gills will incapacitate it. Thanks to this, he survived.

The brain does indeed have an amazing ability to alter your speed of thought and delay time perception when you are in danger, or the so-called “fight-or-flight” mode. There is much anecdotal evidence of firefighters instinctively knowing that a building will collapse very soon, or emergency physicians making complex clinical decisions in the blink of an eye by drawing from a well of past experiences.

Calvin and Hobbes

Posted in Science & Nature

Lizard People

Posted on by Jinavie

What would the world be like if the dinosaurs had not gone extinct? In 1982, palaeontologist Dale Russell proposed a thought experiment regarding the possible evolutionary path of a species called Troodons. The Troodons were small, bird-like dinosaurs from the later periods of the reign of dinosaurs. They grew up to 2.4m in length and about 50kg in weight, standing on two slender hind legs. The most interesting feature of Troodons was their very large brain – six times larger than any other dinosaurs relative to their body weight. This would have most likely allowed the Troodons to be quite intelligent relative to other species, allowing it to utilise crude tools such as rolling a boulder off a cliff.

Russell believed that had the Cretaceous-Paleogene extinction event did not happen 65 million years ago (when a giant meteor struck Earth), the Troodons could have evolved in a path similar to humans, expanding their brain size and using intelligence as a tool of survival. Although its brain size was substantially lower than that of a human, he believes that through evolution, by the present its brain would be the size of a modern human’s. He also believed that evolution would have shaped the Troodons into a “dinosauroid” form, much closer to the shape of a human being. The Dinosauroid (nicknamed lizard people) would have had two fingers and a thumb, large eyes, no hair, internal genitalia (like reptiles), no breasts and a navel (the placenta is instrumental in giving birth to large-brained offspring). Their language would probably have sounded like a bird song.

Given the history of Homo sapiens and our competition and ultimate demise of similar sapient species, it is unclear whether we would have won the survival war against the Dinosauroids, or whether we would have even had the chance to evolve to our stage, as mammals rapidly filled the niche after dinosaurs were wiped out. There is much criticism of Russell’s thought experiment of the Dinosauroid being “too anthropomorphic” (too human-looking), but as suggested in the book K-PAX by Prot, perhaps the humanoid form is the most efficient natural design for an intelligent life form. Realistic or not, it is a fascinating projection of a world that could have been.

Posted in Psychology & Medicine

Memories

Posted on by Jinavie

When you remember a scene from the past, you are not remembering the past. You are remembering a memory of the past. Your brain works in a very funny way where it does not record memories like film. Instead, it seems to remember things as a collage. Everytime you recall a memory – whether it be a happy memory of your first love, or a sad memory of lost love – your brain recalls your last recollection of the event. Simply put, every time you “remember” something, you are merely remembering the latest memory of the event. Each time you replay an event in your mind, it is rewriting a version of the memory over itself.

This means that the more you dwell on a memory, the more it is distorted. You romanticise the good parts and dramaticise the bad parts. The memory is ultimately warped beyond the point of telling the true story. Instead, it becomes something akin to a movie script or a fairy tale. But if it truly is a memory you deem special and hold dear, then maybe it isn’t too bad keeping a romanticised, “perfect” version of it somewhere in your heart to look back on every now and then.

Posted in Psychology & Medicine

Autopilot

Posted on by Jinavie

Anyone who drives to work knows the strange sensation of realising that you have no memory of driving the last few kilometres. It is as if you turn on an autopilot in your brain. Because your brain is a master of pattern recognition, it analyses the route and all the movements like handle turning that takes you to the destination then converts it into a habit. After many commutes, the habit is so strong that the brain does not need to spare any thought on the activity. Ergo, your brain literally turns on an autopilot for you so to spare brainpower.

Thanks to this autopilot, the brain does not have to think about the drive to work. This means that it creates no new memories about the commute and you come out the other side not remembering the drive. An analogy would be to think of your brain’s information processing ability as if it was taking photos. The more new information it processes, the more photos it takes. Because your commute is an automatic process, the brain takes hardly any photos. Therefore, the “album” has few photos and takes little time to flip through. In comparison, your brain takes far more photos if you were to spend an equal time exploring a new scenic route. When you look back on this drive, the album is much thicker and you perceive it as a longer, more detailed memory.

Of course, this is extremely dangerous as your brain’s autopilot does not protect you from changes to your usual commute, such as a car swerving into you by accident. The automatic process means your brain is less ready for information processing and you have a delayed reaction, which may cost you your life.

The same goes for meeting a new person. On a first date, you learn many things about the other person and your brain frantically takes as many photos as it can. Looking back on it, it feels as if every second lasted forever and you can remember every little detail like the song that was playing in the background or the colour of her nails. But twenty years down the line, a day with that same person might feel less special and more “automatic”. Just like your drive to work, such an “autopilot” might result in a horrible accident.

So never stop paying attention to details, avoid forming ruts with surprises and new things. Don’t let your relationship turn into a boring commute.