Tag: smell

Posted in Psychology & Medicine

Proust Effect

Posted on by Jinavie

In his novel In Search of Lost Time, French writer Marcel Proust explored the power of smell in invoking memories. He tells a story of how he would have tea-soaked madeleine to trigger memories from his childhood. Proust called these memories involuntary memories, because it is not recalled on purpose, but automatically triggered by a sensory stimulus such as smell.

Our brain processes memory in a strange, abstract way. Because it doesn’t record memories like a photograph or video, memories become unreliable the older they are. We have very limited memories of our childhood, unless they are paired with specific emotions or memorable events.

Smell triggers involuntary memories because the part of the brain that senses smell, the olfactory bulb, lies right next to the hippocampus and amygdala. These sections of the brain handle memory and emotion respectively, so there is a theory that we form memories linked to different smells, especially if it is an emotional one. There is also some research to suggest a phenomenon called reminiscence bump, where we have a tendency to recall more triggered memories from adolescence and early adulthood. This may be because these are the years when we form our self-identity.

This may be why smells of certain dishes or baking may act as powerful mediums to recall treasured childhood memories, such as the love we received from our parents. Even as adults, we all have specific dishes that we crave to comfort us when we are feeling stressed or lonely. More often than not, these dishes will have a story behind them, whether you remember it consciously or not. When we smell the dish being prepared, we become drowned in nostalgia. The emotions of happiness, safety and love linked to these memories distract us from the pains of life for just long enough that we can have the strength to make it through another day.

Proust talked about a tea-soaked madeleine being his key to his memories. What food is the proverbial madeleine to you?

What food triggers your nostalgia?

Posted in Psychology & Medicine

A Sensational Experience

Posted on by Jinavie

We use our senses to interpret the world around us. Thanks to photography, video and sound recording, we are able to preserve what we see and hear in our lives. If you have the good fortune of seeing an incredible view such as a beautiful sunset, you can take a photo, look at it ten years later and remember what it was like watching it with your own eyes. If you miss the sound of your loved one’s voice, you can record the sound and play it again.

However, we are still unable to record senses such as taste, smell and touch. No matter how hard you try, you can never perfectly describe the taste of your mother’s cooking, the soft touch that you felt during your first kiss, or the scent of the person you love to another person using just words. This means that these sensations are only in your memories – and yours alone.

It is a shame that you cannot recall these experiences perfectly, as some of our best memories are associated with them. But perhaps you could think of it from a romantic point of view. You can share a photo or a sound clip with others to share your experience – even make it public so that everyone can know of it. However, with things like taste and smell, only you will know and remember that specific sensation. It is a truly unique experience that belongs only to you (and the few others who were lucky to have tasted your mother’s cooking).

Furthermore, as it is only in your memories, the moment you forget about it, the experience will disappear forever. Maybe that is why people cling to nostalgia of these senses – because it is a fragile yet precious thing that is worth treasuring and holding on to.

Posted in Science & Nature

Shrew

Posted on by Jinavie

A shrew is a small rodent, similar in size to a rat, that has many fascinating characteristics.

Funnily enough, this animal has a notorious name in history. Ancient Egyptians considered shrews the spirits of darkness and the English believed that if a shrew ran over a lying animal, the animal would suffer great pain. The name shrew comes from the Middle Age English word shrewe, which meant “evil” or “scolding person”.
This is probably attributable to the putrid smell a shrew makes when threatened, and its poisonous bite.

Despite its tiny figure, the shrew has the greatest surface-area-to-weight ratio out of any mammal on the face of the Earth. Because of this, they also have a high heat expenditure, meaning they have to eat constantly to replenish the energy. This means that they sometimes die from starvation during prolonged naps.
Also, they have an extremely high heart rate, averaging about 700 beats per minute. When they are frightened, the heart rate can spike leading to cardiac arrest. For example, shrews are known to die from being frightened by the sound of thunder.

An animal that dies if it naps too much or when thunder strikes – the shrew is a very sad animal.

Posted in History & Literature

Black Death

Posted on by Jinavie

This disease, also known as Pest or the bubonic plague, was a vicious infectious disease that decimated medieval Europe. It is caused by the bacteria Yersinia pestis, usually transmitted by fleas. The symptoms vary from high fever, malaise, nausea and vomiting, headaches, muscle cramps, seizures, red rashes, coughing and swollen lymph nodes, and causes death within four or five days without treatment.
People did not know about the existence of bacteria back then (it would be 200 more years until Louis Pasteur would suggest germs as the cause of infections). Back then, they considered diseases to transmit through miasma, or bad air. Also, they believed that to prevent transmission, they required a stronger smell to counter it.

Plague doctors, who treated according to the miasma theory of disease, wore a special set of equipments that were known as beak doctor costumes. They wore an overcoat, hat, gloves and boots made from waxed leather, carried a cane to assess the patient and point things out, and a peculiar mask. The mask had a long beak like a bird’s, giving the doctors the nickname beak doctors. The masks had round, glass windows to see through, and two small nostrils at the end of the beak.

Why did they wear this strange mask? The beak was hollow and doctors filled it with flowers, herbs, vinegar and incense that produce a strong smell, so as to “purify” the air coming through the nostrils. 
Although the miasma theory has been falsified by germ theory, this gear was the first hazmat suit in history.

There is another fascinating fact regarding the Plague, miasma theory and beak doctors. It regards the nursery rhyme, Ring a Ring o’ Roses:

Ring-a-ring-a-roses,
A pocket full of posies; 
Atishoo! Atishoo! 
We all fall down. 

This nursery rhyme actually describes the Plague. The ring of roses refers to the red rashes and swelling of lymph nodes – a symptom of the Plague; the posies were herbs used to counter the miasma; coughing and sneezing were end-stage symptoms before death, which is shown in the final line. 

Posted in Philosophy

An Opinion On The Senses

Posted on by Jinavie

There are five physical senses and five mental senses.

The physical senses are sight, hearing, touch, taste and smell.

The mental senses are emotions, imagination, intuition, understanding and inspiration.

If a person only uses their five physical senses to live, that is like using the five fingers on their left hand only.

(Die fünf Sinne (The Five Senses) by Hans Makart, 1840-1884)

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 Psychology & Medicine

Sensory Illusion

Posted on by Jinavie

The five senses we use to experience the world are simply wondrous. However, thanks to our not-so-perfect brain, these senses can easily be distorted. Illusions are a very good way to show how the brain processes sensory information and there are many fascinating examples.

Almost everyone has seen an optical illusion before, such as Penrose’s endless stairs or the Muller-Lyer illusion. There are countless more examples such as static pictures that appear to be moving and illusions in colour perception (A and B are the same colour). This is caused by the brain not recording images like a camera, but rather processing visual information and reconstructing an image. There are four main types of optical illusions: ambiguous (e.g. rabbit or duck), distortion (Café wall illusion), paradoxical (Penrose triangle) and fictional (only seen in hallucinations or by schizophrenics).

(Do you see the dolphins? Children cannot see the man and woman because they cannot comprehend it, whilst adults cannot overpower the sexual image)

Like vision, every other sense can be fooled in a similar fashion.
Auditory illusions that distort what we hear are fairly common, a good example being the infinitely ascending Shepard scale (which are just a series of the same ascending octave scale). Also, the McGurk effect shows how the brain uses a multimodal approach where it involves both hearing and vision when listening.

There are also tactile illusions. For example, if you pull your top lip to left and the bottom lip to the right, then prod the middle of the lips with a pencil, it feels like there are two. However, the more famous case is of the Phantom Limb, where an amputee’s brain still believes that the limb is there, causing it to “feel” the limb or even feel pain.

The other two senses aren’t as famous in terms of illusions, but definitely exist.
Smell is easy to fool through chemicals as it is the physiological method of detecting smell. It also exhibits olfactory fatigue where it becomes desensitised to a strong smell.
Taste illusions are more fascinating and easily seen. They are caused by two or more tastes forming a synergy to produce a completely different taste. For instance, mixing barley tea and milk produces a coffee milk taste, while cucumber and honey tastes like melons.
A more fascinating illusion involves Miracle Fruit Berries, which contain a substance called miraculin that distorts the taste of sourness to sweetness.

This shows how we can fool all five senses, and learn more about the mysterious organ that is the brain.