The Science of Consciousness

What does consciousness mean from a scientific perspective? Is there such a thing as "the science of consciousness"?

There are in fact two kinds of science of consciousness:

1. science of consciousness from the outside.
   
2. science of consciousness from the inside.
   

The science of consciousness from the outside

This is science in the modern sense, as in neuroscience. Information about the brain and its role in consciousness has been gained through experiments. For example, an experimental subject (a person) is asked to do something and, while they are doing it, measurements are taken of the activity of their brain.  

Anatomy of the Brain

Your brain weighs around 1.4 kg (or 3lb). It is grey on the outside and wrinkled like a walnut. Just like a walnut it has two halves. A view of the brain sitting in your skull is shown in the diagram below. The view is from above, looking down. (Note that the colours are part of the illustration and not of the brain itself).

Scientists are already familiar with the anatomy of the brain - the different parts it has and where they are in relation to each other inside the skull. Here is a side view of the left hemisphere. Again, colours are used in the illustration to help identify the different parts. The surface of the brain (except for the cerebellum and spinal cord) is grey all over and is called the cortex.

Here is an illustration of the inside of the brain. The brain has been sliced down the middle, between the two halves, and then opened up so you can see inside.

This knowledge originally came from dissection of dead bodies. Now, images of the inside of any part of the body can be made using an X-ray machine or an MRI scanner, without cutting the body open. This makes it much easier to gather information to help develop the science of consciousness.

MRI Scanner

MRI is short for "Magnetic Resonance Imaging". An MRI scanner uses the fact that the nucleus of a hydrogen atom behaves like a very weak magnet. Hydrogen atoms are found throughout the body in water molecules and in the fatty tissues such as those found in the brain. These extremely little magnets in your body can be influenced by the strong magnetic field from the scanner.

Here's how it works:

First, you lie on a bed which is then moved inside the scanner.

Inside the scanner, a very strong magnetic field causes the tiny hydrogen magnets in your body to align themselves with the field - just like a magnet in the lab can make iron filings line up. The scanner then applies a varying magnetic field on top of the fixed one.

This varying magnetic field vibrates at a specific frequency that makes the tiny hydrogen magnets vibrate. They "resonate" with the vibrating field. As they do this, they pick up energy.

When the vibrating field is  switched off, the nuclear magnets settle back to the fixed direction, releasing their vibrational energy in a burst of radio waves.

These bursts are detected by special sensors in the scanner. The process is repeated many times and, with the help of a computer, the MRI machine forms an accurate image of the inside of the brain.

The image is presented in the form of "slices". Doctors and brain scientists can look at different slices to help them work out what is going on.

The MRI scan shows the position of nerves, blood vessels and fatty tissues in the different parts of the brain. Any abnormalities can be seen, which is why MRI scanning is widely used in medicine.

EEG

Another way of investigating what is going on in your brain is by measuring the small electrical signals that can be found on your scalp. These signals change as your consciousness changes. The signals are measured using a special cap which has electrodes all over it, covering your scalp. 

A recording made from the electrodes in the cap is called an EEG (short for Electroencephalogram). The results are displayed in graph form, showing how the tiny voltages at each point of the scalp vary as brain activity changes.

fMRI

The science of consciousness needs to explain how the brain works to create consciousness, with all the different parts working together to make a single whole.  A functional MRI scanner (an fMRI scanner) helps because it can show up which parts of the brain are actually "live" for each of the different aspects of our conscious activity. Aspects such as, thinking, feeling, seeing, remembering etc. 

fMRI does this by measuring changes in the flow of blood through the different parts of the brain.

When a part of the brain is active it needs more oxygen which is supplied by the blood. It is this increased flow of oxygen-carrying blood which is directly "seen" by the fMRI scan, revealing exactly which parts of the brain are active and which are not for the each task.

On the scans shown on the medical tablet below, the parts that show up red are the parts that are active.

Results

The cerebral cortex is associated with intelligence, personality and conscious thought; it is also associated with language and verbal memory. The cerebellum also plays a role in thought, plus emotions and social behaviour.

The cerebral cortex is heavily folded and divided into 4 lobes on each side. Each lobe has a role in conscious activity. For example, the frontal lobe of the cortex plays a key role in decision-making, whilst the rear lobe (parietal lobe) is associated with vision. Memory, like consciousness, has no obvious single centre but is associated with a number of centres from different parts of the brain.

You can find out more about the brain at John Hopkins Medicine

Conclusions

Consciousness, from this external scientific perspective seems to be associated not with any specific centre but with the organisation of the activity of different parts of the brain - each acting coherently with the others. Brain scientists are still trying to pin this idea down using mathematical models.

Scientists have divided consciousness into three parts:

1. Wakefulness (I am awake not asleep)
2. Awareness (My attention is working; I am aware of something)
3. Sensory experience (I can see my dog)

They have a lot of information about each of these aspects but not on how they work together. In other words, the science of consciousness from the outside is incomplete.

The scientific viewpoint

Scientists tend to believe that the physical world is primary and the mental world secondary. Therefore, although the exact details are not clear, many  scientists think that our consciousness and its associated mental states must be caused by the the way the different parts of the brain work together.

Or we could say that, as far as brain science is concerned, our mental states are the inner aspects of consciousness and the way our brains work are the outer aspects. Philosophically speaking, this is a kind of Panpsychism. We'll explain what that means in our Philosophy of Consciousness page.

The science of consciousness from the inside

From a spiritual perspective, the science of consciousness from the outside, has things the wrong way round.

Consciousness is a different kind of thing from the material of our bodies, including the brain. Certainly, the activity of the brain as measured by scientists reflects our state of consciousness but remember what we said on our home page:

Our individual consciousness is like a reflection of the sun on a glass of water:

Our consciousness is more fundamental than a collection of different brain parts working together. Our consciousness defines who we are. And "who we are" has a self at the basis of all our conscious activities and experiences.

The self is like the reflection in the water. Although the quality of the reflection depends on the quality of the water, the reflection itself is not the water.

The science of consciousness from the inside begins with this reflection and its source. You'll find more about it on the Pure Consciousness page  here: