Tag: memory

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

Transactive Memory

Posted on by Jinavie

It is common to find couples, families or teams where someone always asks another member about a certain memory, while the opposite happens for a different memory. For example, a mother might always consult his son about computers and technical difficulties, while the father might always consult the mother about his plans for the month. This kind of “shared memory” is named transactive memory, where a group becomes organised in a way to share memory around in an efficient manner. This is usually done by the group reorganising itself so that each member specialises in a certain field, with the other members only remembering that that person is the expert. This means that instead of memorising every field, you can simply remember who is the expert in that field. It is much like learning where the reference text is rather than learning the contents.

Although it may look like dependence, transactive memory is an extremely useful tool in tight groups such as a couple or a small team. By having members specialise in certain domains of knowledge, the group is able to expand their capacity to acquire knowledge and create innovation. Transactive memory allows for a group to become efficient and effective in learning and retrieving knowledge. Overall, it improves decision making processes and the efficiency of the group, allowing for better outcomes. This is achieved by the division of responsibilities from specialising, shortening the time needed for finding the appropriate knowledge (as everyone knows the “guy” or “gal” to go to) and the shared understanding of the teammates regarding the interpersonal relations in the team. This means that everyone knows exactly who to go to for a certain domain of knowledge, while understanding their strengths and weaknesses, allowing for well coordinated interactions. Because of this, transactive memory only works in groups with limited numbers, with the maximum number being similar to the Monkeysphere (150).

Many studies prove the effectiveness of transactive memory. It has been found that couples have much better memory recollection compared to when they are paired with a stranger. In the modern technological era, transactive memory has expanded to the internet, with studies showing that people are more likely to know the source of information (such as Wikipedia) rather than the actual information. Given the ease of access to the internet and large databases containing all the information we need, sometimes it is far more efficient learning how to find these sources rather than rote learning all the information.

Posted in Life & Happiness

Forgetting

Posted on by Jinavie

“Blessed are the forgetful for they get the better even of their blunders.” ~ Friedrich Nietzsche

If you could forget a horrible memory or experience forever, would you? Although some traumatic experiences are best forgotten, something like a break up may leave painful yet bittersweet memories. Does the cost of heartbreak outweigh all the precious memories you had with that person? There may be doubt that you may miss the lovely memories and regret your decision, but ultimately without the memory you will have no regret either. Is ignorance bliss?

Posted in Psychology & Medicine

Fugue State

Posted on by Jinavie

Any computer user would have had an (unfortunate) experience where their computer crashed and all the information there was destroyed in a second. You may still be able to format it and use it without problems, but the data you had on the computer and any customisation you made would be lost. But what if this exact thing could happen to a human being?

There are many types of amnesia, with causes ranging from neurobiological (where trauma to the brain, a drug or some other pathology causes memory loss) to psychogenic (where there is no apparent biological cause for the amnesia). With psychogenic amnesia, one only experiences retrograde amnesia, where they cannot recall memories from the past. However, anterograde amnesia, where you cannot form new memories and keep forgetting what happened, is absent in psychogenic amnesia. Psychogenic amnesia is often caused by extreme stress or a traumatic event. One type of psychogenic amnesia is situation-specific amnesia, as seen in post-traumatic stress disorder (PTSD) that occurs after a severely stressful experience such as war, rape, child abuse or witnessing a brutal death. In this case, the patient tends to only lose memories regarding the event, as if the brain is trying to protect the person from the hurtful memories.

A more interesting and much rarer type of amnesia is global psychogenic amnesia, also known as a fugue state or dissociative fugue. Unlike situation-specific amnesia, patients in fugue states have absolutely no memory of their original identity and personality. Simply put, they (usually) retain all their functions such as speaking and social interactions, but their persona has been wiped out like a formatted computer. Fugue states often develop after severe stress and can happen to anyone. Similar to situation-specific amnesia, the brain blocks all memories of the past in an attempt to protect the person’s psyche. Due to the “deletion” of the previous persona, patients in fugue states often generate new identities and begin wandering (sometimes even travelling to another country) away from the place they lost their memories. This is most likely the brain attempting to leave the environment to avoid the stressor that caused the event. 

Fugue states are often short-lived, lasting from days to months. However, very rarely they can last for years. Once out of a fugue state, the patient recovers all of their past memories but have no recollection of what happened during the fugue state. This creates a hole in their memory. For obvious reasons, this usually causes intense confusion and distress in the patient and treatment is often based around helping the person come to an understanding about the episode and cope with the stressor that caused it.

Posted in Psychology & Medicine

Korsakoff’s Syndrome

Posted on by Jinavie

It is a well-known fact that excessive drinking leads to a so-called “blackout”. This form of memory loss is common in normal people and cannot be seen as a major illness. However, there is another disease that can be caused by excessive drinking called Korsakoff’s syndrome. Strictly speaking, this is not caused by alcohol but due to a thiamine (vitamin B1) deficiency and is commonly found in alcoholics and malnourished patients (it has also been reported to be caused by mercury poisoning and after centipede bites in Japan).

The six characteristic symptoms of this syndrome are: anterograde (cannot form new memories) and retrograde (cannot remember old memories) amnesia, confabulation, lack of detail in conversation, lack of insight and apathy.

Korsakoff’s syndrome patients show a very peculiar behaviour. As stated before they suffer from both anterograde and retrograde amnesia so not only can they not remember the past but they cannot make new memories either. Ergo, the brain uses information from its surroundings and attempts to recreate the lost memories, the result being confabulation. Confabulation is essentially what happens when the brain tries to fill in blanks in memories with false information. Confabulation is seen in everyday life too with healthy people but in the case of Korsakoff’s patients the effects are significantly more profound. For example, if you ask a patient what she did yesterday, she may look at your horse-print tie and claim she was horse-riding. If you ask the same question an hour later without your tie and instead holding a book with a photo of a Ferris wheel on the cover, she’ll state that she was at the amusement park. As one of the leading causes of amnesia and confabulation, Korsakoff’s should be suspected in any alcoholic or very underweight patient who keeps changing their stories around. 

As previously explained, the disease is caused by thiamine deficiency – therefore, the treatment is administering thiamine. But if the syndrome has persisted for a long time, the brain injury may be permanent. Also, treating the underlying alcoholism and malnutrition is important. 

If the thiamine deficiency is prolonged, it may lead to another disease called Wernicke’s encephalopathy. This is known as Wernicke-Korsakoff’s syndrome and in addition to the above symptoms, the patient may also experience confusion, tremors, nystagmus, paralysis of eye muscles, ataxia, coma and can eventually lead to death. All because of a deficiency of a single vitamin.

Who said nutrition is not important?

image

(NB: Dory from Finding Nemo is one of the most accurate portrayals of amnesia in films)

Posted in Psychology & Medicine

Cranial Nerves

Posted on by Jinavie

Nerves can be divided broadly as spinal nerves and cranial nerves: the latter which is directly from the brain. There are 12 pairs of cranial nerves:

  1. CN I – Olfactory nerve (smell)
  2. CN II – Optic nerve (sight)
  3. CN III – Oculomotor nerve (eye movements, control of pupil and lens)
  4. CN IV – Trochlear nerve (eye movements)
  5. CN V – Trigeminal nerve (sensory information from face and mouth, chewing)
  6. CN VI – Abducens nerve (eye movements)
  7. CN VII – Facial nerve (taste, tear and salivary glands secretion, facial expressions)
  8. CN VIII – Vestibulocochlear nerve (hearing and sense of balance)
  9. CN IX – Glossopharyngeal nerve (taste, swallowing, parotid gland secretion, sensory information from oral cavity, information about blood)
  10. CN X – Vagus nerve (sensory and motor signals to and from many internal organs, glands and muscles)
  11. CN XI – Accessory nerve (movement of SCM and trapezius, which are neck/shoulder muscles)
  12. CN XII – Hypoglossal nerve (tongue movements)

As there are so many nerves and the names are all varied, there is a simple (yet very obscene) mnemonic to help medical students remember the names and order of nerves:

Oh, Oh, Oh, To Touch And Feel Virgin Girls’ Vaginas And Hymens
or
Oh, Oh, Oh, To Touch And Feel A Girl’s Very Soft Hands
(where vestibulocochlear -> auditory)

It is also worth noting the mnemonic for the types of nerves is:

Some Say Marry Money, But My Brother Says Big Boobs Matter More

Perhaps the only way to survive medical school is through humour.

Posted in Philosophy

Evidence

Posted on by Jinavie

When a person dies, what do they leave in the world? As an old proverb states, tigers leave their hide after death and people leave their name after death. Little is left after death: bodies slowly decay and return to the ground, wealth is split up and taken by others. If you think about it, the only thing that remains as evidence that the person existed is their name, and people’s memories regarding that name. Official records or photos can be lost among time and forgotten about, but a strong bond between people is hard to forget.

But as even memories fade away, a person who you met once or twice will be forgotten eventually. Therefore, a person who never was close to people or make an impact in someone’s life would “not have existed” to anyone other than a select few, such as family. Therefore, his or her life would have had no meaning, as it may have never existed. Although some may argue that there would have been meaning while the person was alive, there is no greater meaning outside of the past and present, with no impact in the future.

However, if one is close to many people and actively leaves some mark in someone’s life, they will be remembered for those “marks”. In other words, the way people see you is how you will be remembered after death, and by extension, it will define who you were. If you were generous and kind, you become a “good person” forever, but if you did not interact with people or treated them with little respect, you are then defined as a “not so good person”, or even worse, not defined at all. This is regardless of what kind of person you are on the inside, as that would be completely destroyed after death.

The main point of this thought process is that if you do not leave some evidence that you existed, more specifically a good mark, whatever you did in your life will be meaningless. One could accomplish a great feat and have their name known across the world, or leave a work of art or literature that will be seen and read, or even just befriend many people and leave an everlasting impression of yourself in their mind. 

But if you do not want your life to have any impact on the future, there is the option of simply enjoying the present and disappear as Andersen’s Little Mermaid did.
Ergo, it is ultimately your choice whether you want to leave a mark in the world or not.