Archive for ‘Miscellaneous’

March 31, 2013

The illustrated guide to a Ph.D.

Source: The illustrated guide to a Ph.D.

Every fall, I explain to a fresh batch of Ph.D. students what a Ph.D. is. It’s hard to describe it in words. So, I use pictures.

Read below for the illustrated guide to a Ph.D.

Imagine a circle that contains all of human knowledge:

By the time you finish elementary school, you know a little:

By the time you finish high school, you know a bit more:

With a bachelor’s degree, you gain a specialty:

A master’s degree deepens that specialty:

Reading research papers takes you to the edge of human knowledge:

Once you’re at the boundary, you focus:

You push at the boundary for a few years:

Until one day, the boundary gives way:

And, that dent you’ve made is called a Ph.D.:

Of course, the world looks different to you now:

So, don’t forget the bigger picture:

Keep pushing…

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March 30, 2013

The Human Brain

Origin of information:Top 10 Myths About the Brain

The brain is one of the most amazing organs in the human body. It controls our central nervous system, keeping us walking, talking, breathing and thinking. The brain is also incredibly complex, comprising around 100 billion neurons. There’s so much going on with the brain that there are several different fields of medicine and science devoted to treating and studying it, including neurology, which treats physical disorders of the brain; psychology, which includes the study of behavior and mental processes; and psychiatry, which treats mental illnesses and disorders. Some aspects of each tend to overlap, and other fields cross into study of the brain as well.
Many animals can use their brains to do some of the things that humans can do, such as finding creative ways to solve problems, exhibiting self-awareness, showing empathy toward others and learning how to use tools. But although scientists can’t agree on a single definition of what makes a person intelligent, they do generally agree that humans are the most intelligent creatures on Earth. In our “bigger is better” society, then, it might stand to reason that humans should have the biggest brains of all animals, because we’re the smartest. Well, not exactly.
The average adult human brain weighs about 3 pounds (1,361 grams). The dolphin — a very intelligent animal — also has a brain that weighs about 3 pounds on average. But a sperm whale, not generally considered to be as intelligent as a dolphin, has a brain that weighs about 17 pounds (7,800 grams). On the small end of the scale, a beagle’s brain is about 2.5 ounces (72 grams), and an orangutan’s brain is about 13 ounces (370 grams). Both dogs and orangutans are pretty smart animals, but they have small brains. A bird like a sparrow has a brain that weighs less than half an ounce (1 gram).
You may notice something important in all of those comparisons. An average dolphin’s body weighs about 350 pounds (158.8 kilograms), while a sperm whale can weigh as much as 13 tons. In general, the larger the animal, the larger the skull, and therefore, the larger the brain. Beagles are fairly small dogs, at about 25 pounds (11.3 kg) maximum, so it stands to reason that their brains would also be smaller. The relationship between brain size and intelligence isn’t really about the actual weight of the brain; it’s about the ratio of brain weight to the entire body weight. For humans, that ratio is about 1-to-50. For most other mammals, it’s 1-to-180, and for birds, it’s 1-to-220. The brain takes up more weight in a human than it does in other animals.
Intelligence also has to do with the different components of the brain. Mammals have very large cerebral cortexes, unlike birds, fish or reptiles. The cerebellum in mammals houses the cerebral hemispheres, which are responsible for higher functions like memory, communication and thinking. Humans have the largest cerebral cortex of all mammals, relative to the size of their brains.

March 30, 2013

Who Are We? Experiments Suggest You’re Not Who You Think

This article is taken from: Who Are We? Experiments Suggest You’re Not Who You Think

“Who in the world am I?” asked Alice (in Wonderland). “Ah, that’s the great puzzle!” The question may make you wonder about taking time to ponder such philosophical babble. The answer is usually defined by what you can control. A reply might be, “I can wiggle my toes but I can’t move the legs of the table.” The dividing line between self and nonself is taken to be the skin. This is reinforced every day of our lives — every time you fill out a form: I am ___ (your name here). It’s such an integral part of our lives that the question is as unnatural as scrutinizing breathing.

Years ago I published an experiment (Science, 212, 695, 1981) with Harvard psychologist B.F. Skinner (the “father” of modern behaviorism) showing that like us, animals are capable of ‘self-awareness.’ We taught pigeons to use a mirror to locate a spot on their body which they couldn’t see directly. Although similar behavior in primates is attributed to a self-concept, it’s clear there are different degrees of self-awareness. For instance, we didn’t report in our paper that the pigeons attacked their own reflection in the mirror. Biocentrism suggests we humans may be as oblivious to certain aspects of who we are as the pigeons.

We are more than we’ve been taught in biology class. Everyday life makes this obvious. Last weekend I set out on a walk. There was a roar of dirt bikes from the nearby sandpit, but as I went further into the forest the sound gradually disappeared. In a clearing I noticed sprays of tiny flowers (Houstonia caerulea) dotting the ground. I squatted down to examine them. They were about a quarter-of-an-inch in diameter with yellow centers and petals ranging in color from white to deep purple. I was wondering why these flowers had such bright coloring, when I saw a fuzzy little creature with a body the size of a BB darting in and out of the flowers. Its wings were awkwardly large and beating so fast I could hardly see their outline. This tiny world was as wondrous as Pandora in Avatar. It took my breath away.

There we were, this fuzzy little creature and I, two living objects that had entered into each others’ world. It flew off to the next flower, and I, for my part, stepped back careful not to destroy its habitat. I wondered if our little interaction was any different from that of any other two objects in the Universe. Was this little insect just another collection of atoms — proteins and molecules spinning like planets around the sun?

It’s true that the laws of chemistry can tackle the rudimentary biology of living systems, and as a medical doctor I can recite in detail the chemical foundations and cellular organization of animal cells: oxidation, biophysical metabolism, all the carbohydrates, lipids and amino acid patterns. But there was more to this little bug than the sum of its biochemical functions. A full understanding of life can’t be found only by looking at cells and molecules. Conversely, physical existence can’t be divorced from the animal life and structures that coordinate sense perception and experience (even if these, too, have a physical correlate in our consciousness).

It seems likely that this creature was the center of its own sphere of physical reality just as I was the center of mine. We were connected not only by being alive at the same moment in Earth’s 4.5 billion year history, but by something suggestive – a pattern that’s a template for existence itself.

The bug had little eyes and antenna, and possessed sensory cells that transmitted messages to its brain. Perhaps my existence in its universe was limited to some shadow off in the distance. I don’t know. But as I stood up and left, I no doubt dispersed into the haze of probability surrounding the creature’s little world.

Science has failed to recognize those properties of life that make it fundamental to our existence. This view of the world in which life and consciousness are bottom-line in understanding the larger universe — biocentrism — revolves around the way our consciousness relates to a physical process. It’s a vast mystery that I’ve pursued my entire life with a lot of help along the way, standing on the shoulders of some of the most lauded minds of the modern age. I’ve also come to conclusions that would shock my predecessors, placing biology above the other sciences in an attempt to find the theory of everything that has evaded other disciplines.

We’re taught since childhood that the universe can be fundamentally divided into two entities — ourselves, and that which is outside of us. This seems logical. “Self” is commonly defined by what we can control. We can move our fingers but I can’t wiggle your toes. The dichotomy is based largely on manipulation, even if basic biology tells us we’ve no more control over most of the trillions of cells in our body than over a rock or a tree.

Consider everything that you see around you right now — this page, for example, or your hands and fingers. Language and custom say that it all lies outside us in the external world. Yet we can’t see anything through the vault of bone that surrounds our brain. Everything you see and experience — your body, the trees and sky — are part of an active process occurring in your mind. You are this process, not just that tiny part you control with motor neurons.

You’re not an object — you are your consciousness. You’re a unified being, not just your wriggling arm or foot, but part of a larger equation that includes all the colors, sensations and objects you perceive. If you divorce one side of the equation from the other you cease to exist. Indeed, experiments confirm that particles only exist with real properties if they’re observed. Until the mind sets the scaffolding of things in place, they can’t be thought of as having any real existence — neither duration nor position in space. As the great physicist John Wheeler said, “No phenomenon is a real phenomenon until it is an observed phenomenon.” That’s why in real experiments, not just the properties of matter — but space and time themselves — depend on the observer. Your consciousness isn’t just part of the equation — the equation is you.

After she left the pool of tears, the Caterpillar asked Alice “‘Who are you?’ This was not an encouraging opening for a conversation. Alice replied, rather shyly, ‘I—I hardly know, Sir…’” Perhaps the Hookah-Smoking caterpillar, sitting there on his mushroom, knew that this unusually short question was not only rude, but difficult indeed.