Category: Neuroscience

What Do The Blind See?

By Anupum Pant

If you are here to judge me because you think you clicked on a completely nonsensical headline, well that is what headlines are for – To get you to open the link and read.
However, I have to tell you that this headline isn’t complete nonsense. There is more to the word blind than just the word alone. The word Blind in itself doesn’t completely define the exact state of a person’s visual ability. So the blind can see, or not, depending on the kind of blindness they are affected with.

Functionally Blind or Legally Blind

First, there is this thing called functional blindness. The functionally blind can see a bit, but not enough to do everyday tasks without hindrance.

Then there is legal blindness which classifies people having visual acuity below some point as blind. Even people with poor peripheral vision are labeled as Legally blind.

Some people might even have something called partial vision loss due to eye related ailments like glaucoma or cataract. The vision in such cases could be blurred or narrow.
In short, despite being classified as “blind”, people with functional, partial or legal blindness can see at least something. They can perceive light. But not all kind of blind people can perceive light.

Total Blindness

People who are totally blind cannot see. They see nothing. It is called NLP (No Light of Perception). For the people who can see naturally without making any conscious effort, the concept of being able to see nothing can be a very profound concept to grasp. Explaining the meaning of nothingness to a not-blind person is exactly the same as explaining the concept of color to a totally blind person. Experience of one sense can in no way be explained by referring to some other sense. It is a subjective experience.

Some totally blind people are able to map out a 3D image of the world through their eyes. They literally see through their ears. And this can be learnt. – Read more.

There are also some cases where even totally blind can perceive light to some extent. – Source

Is Black = Nothing?

Contrary to what most of us assume, the color black is NOT nothing. You’d assume that a person who is totally blind would see black, like you do when you close both your eyes. But seeing black is not seeing nothing.

Suppose, if you’d ask a totally blind person to describe the color black because you’d assume he always sees it, he’ll not be able to describe it. To experience nothingness to some extent, you can do this:

Close your left eye. Now you are seeing through your right eye. Focus of things with your right eye. But, what you are seeing with your left eye is nothing. It is not black. You see nothing.

Meet Tommy

Probably the most popular person here on the internet who can talk to you about total Blindness is, Tommy, who runs a splendid YouTube channel.

Tommy has been blind all his life. He makes great videos. If you haven’t subscribed to his channel, you must do it right now. The channel, on the whole, will give you quite an insight into the concept of No Light of Perception from a first person account of a Totally blind person. Here is one video of his which I loved. He talks about what colors mean for completely blind people.

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Cute Aggression – Hugging The Life Out of Your Puppy

By Anupum Pant

Don’t you feel like pinching the cheeks of a chubby little baby or hugging the life out of your puppy? Even if a kid might find it unpleasant you pinching its cheeks really hard, or even if you’d not want to hurt a little kid, you’d still be bubbling to do it. What is it that forces you to vent out a physical reaction towards cuteness?

Most of us do and science proves that intense cuteness can often manifest itself as aggression. Rebecca Dyer, a graduate student in psychology at Yale University, has coined the phrase cute aggression for this feeling. Scientists are not yet sure on what causes this. According to them:

“It might be that how we deal with high positive-emotion is to sort of give it a negative pitch somehow”

Or probably you, in some way, want to take care of something by ensconcing it in your arms. And when you see and are not able to do it, you vent it out on bubble wrap?

Researchers carried out a study involving bubble wraps. It was found that people who were shown slides/videos of cute animals popped higher number of bubbles than the people who were shown something not so cute, funny or neutral videos.

A YouTube channel, SoulPancake, actually recreated the experiment in their studio and recorded positive results. It was found that cuteness evokes a physical reaction in most people.

McGurk Effect – What You See is What You Hear

By Anupum Pant

Do Not Cheat

  1. Close your eyes: Before you watch this video, you should know that, when you watch it for the first time, you have to watch it with closed eyes. Well, you can’t ‘watch’ with closed eyes. It simply means, you have to just hear the sound track first. I’m sure you can do it because closing eyes for 5 seconds is not asking for much. I don’t have any veiled interests here. It is for you. You won’t appreciate the effect if you keep your eyes open during the first go.
  2. Open your eyes: Watch it again with your eyes open. Be calm. It happens to everyone.

So that was the McGurk effect. It is a perfect example to show that accurate perception of reality may involve more than one sense. This is called “Multimodal perception”. In simple words, our senses do not learn from the surroundings independent from each other, they work together and learn together to help us perceive information.

The video

The video shows a man moving his lips as if saying “Ga” or “Da”, although it is just a visual of him saying that, let us call this the visual for the first sound (“Da” sound). The second sound is the “Ba” sound that is actually playing – this is the second sound.

When your eyes are closed, you hear the correct sound, the second sound – the “Ba” sound.
When you watch it again with your eyes open, you hear the “Da” sound. The brain combines the visual and audio signals to make you believe that the sound you are hearing is actually “Da”. Even if you are aware of this illusion, your brain doesn’t correct it for you, no matter how many times you repeat this.

Some interesting things about McGurk effect

  • You can focus anywhere on the face (not just the mouth) to perceive the same effect.
  • Women show a stronger McGurk effect than men.
  • Normally, people with mental disorders do not hear much difference in the sound with eyes open or closed.
  • By the age of 4 months, infants are able to identify facial movements and relate them to sounds. So, even infants show this effect to a certain extent.
  • Information rich perceptions are easier to remember. So, the next time you are trying to learn something, involve more senses. Probably involving a particular smell that goes with a piece of information will help you remember things well. Or a sound, maybe.

Note: Since my posts were getting longer everyday, I’ve tried to keep this one short. I don’t want the posts to be overwhelming for people who are not used to long reading. This blog is meant to make science sound interesting to everybody, not to scare them away from it. I’ll be waiting to receive your feedback on this. You can get in touch through twitter (@indigoanalysis)

Is There a Scientific Explanation for Everything?

By Anupum Pant

Today we have Dr. Eben Alexander III, an American Neurosurgeon and the author of a number one New York Times bestseller, in the house. Well, not really, but let us imagine he is here with us.

Background: Dr. Eben Alexander has been a member of the American Medical Association, a neurosurgeon and has taught at the Harvard school of medical sciences. He has spent a lot of time among scientists believing that there is always a scientific explanation for everything. But, one day, he experienced something that defied all scientific explanation. Turns out, there isn’t a scientific explanation for everything. Later he went on to write a number one New York Times bestselling book – Proof of Heaven: A Neurosurgeon’s Journey into the Afterlife.

Like logical open-minded Possibilians, let us read the book first, to start arguing against it. I haven’t read it yet. So, for now, I’ll stick to writing about just what I’ve learnt about it, rather than formulating theories against it.

The story: In the year 2008, Eben was affected by a severe case of bacterial Meningitis and fell into a coma for 6 days. His Neocortex showed no signs of activity. When he got cured miraculously (with just 2% survival chance) and returned from coma, he had experienced something out of this world. According to him, during the coma, he had experienced a vivid journey into the afterlife – kind of a near death experience.

The experience: When he fell into coma, he found himself in a dark and suffocating place for a very long time. Later a spinning bright light with a beautiful melody came in slowly and “rescued” him out of this agony. It took him to a fertile green land. Some points that he makes about this mysterious land:

  1. There was no need for a spoken word to communicate there. Every communication was telepathic.
  2. The instant you asked questions, you knew the detailed answers for those questions. (Something similar to the experience of Zen)
  3. The experience was more real than real-life. In comparison, real-life seemed like an illusion.

You can watch a 42 minute long interview here for further details. [Video]
I’d also suggest reading: Supernatural: Meetings with the Ancient Teachers of Mankind

Possibilianism

Although we’ve progressed a lot in science and technology in the past 400 years, there is a much more science doesn’t explain than there are things it can.

For instance, to make our equations sound right, we assume there is something out there we can’t touch, feel or sense in any way; we choose to call it dark matter. The most incredible thing – 90% of our universe is dark matter (and dark energy). That is too much to sweep under the rug. And we know nothing about it.

In the words of David Eagleman – “Our ignorance of the cosmos is too vast to commit to atheism, and yet we know too much to commit to a particular religion.”

Or in the words of Carl Sagan – “An atheist is someone who is certain that God does not exist, someone who has compelling evidence against the existence of God. I know of no such compelling evidence. Because God can be relegated to remote times and places and to ultimate causes, we would have to know a great deal more about the universe than we do now to be sure that no such God exists. To be certain of the existence of God and to be certain of the nonexistence of God seem to me to be the confident extremes in a subject so riddled with doubt and uncertainty as to inspire very little confidence indeed.”

The Purpose of Sleep – Theories

by Anupum Pant

Did you know?

  • You can live longer without food than you can live without sleep.
  • On an average, a person sleeps for 1/3rd of his life. That means if you are 30 years old, you’ve slept for 10 years already.
  • The world record for the longest span remaining awake is 11 days. The record was set by 17-year-old Randy Gardner in 1964 when he was awake for 264 hours and 12 minutes. (Don’t try this)
  • If it takes you less than five minutes to fall asleep then very likely you are sleep deprived. It should take about 10 minutes normally.
  • You can lose up to 2 grams every minute while sleeping. That comes to about a lost Kilogram at night.

What is Sleep?

Everybody sleeps. On an average, everyday, a bat sleeps for 15 hours while just 3 hours are enough for a Horse to feel rested [How much do animals sleep – chart]. Dolphins can sleep with half of their brains active and even the smallest of worms need sleep. But, till date, scientists haven’t been able to reach a consensus on why we actually do it?

Sleep can be understood as a life sustaining activity. It can be compared to another of our important activity – eating. These strongest of the human urges – eating and sleeping – serve a nearly common purpose – quell the urges; just as eating relieves hunger, sleeping relives sleepiness.

While it is true that we may have not been able to spot the primary purpose of sleep, years of research hasn’t gone wasted. With time, we have learnt a lot more about sleep than we used to know 50 years back. There have been hundreds of practical and impractical theories on why we sleep. I’ve mentioned a few of the realistic ones here.

Purpose of Sleep – Theories

Inactivity Theory:

According to this old theory, sleep evolved out of the need to be safe. It suggests that inactivity at night is an adaptation that serves as a survival mechanism. It functions as an activity which would keep an animal safe during the time it is most vulnerable e.g. Humans are vulnerable at night because they don’t see well in dark.

This theory is easily countered using the argument: Being conscious and still, is much better way to stay safe than lying unconscious and still.

Energy Conversation Theory:

It suggests, the main function of sleep is to reduce the demand and consumption rate of energy at times when searching for food isn’t an efficient option. Some believe, that this theory is a part of the inactivity theory. But, unlike the inactivity theory, this theory has been bolstered by various experiments which prove that the consumption of energy is reduced when an organism sleeps.

Restorative theory:

It explains sleep as an opportunity for a body to rejuvenate in terms of muscles, tissues, proteins, cells and growth hormones. Also, during sleep, the body clears an accumulated molecule called adenosine from the system, and makes us feel alert when we wake.

A recent study also seems to support the restorative theory in a fresh manner. It says, brain accumulates toxins [like beta amyloid] while it is awake. The concentration of such toxins keeps increasing during waking state. The study observed an increased activity of spinal fluid being pumped into the brain in rodents (hasn’t been studied on humans yet). This spinal fluid functions as a medium to pump out toxins from the brain. This theory could be a breakthrough in the study of causes and prevention of Alzheimer’s as it is known that toxins like beta amyloid cause the disease in humans [How beta amyloid causes Alzheimer’s].

Brain Plasticity Theory:

According to this, sleep plays a critical role in brain development. Infants (age when the brain develops the most), for example, sleep for about 13 – 14 hours every day. On the other hand, the poor ability to learn and perform tasks due to the lack of sleep explains the role of sleep in adults. Since, It has been proven that brain is highly active during sleep, this theory remains the most plausible one in being able to state one of the functions of sleep.