Controversy and Current Research

We have oodles of recorded observations and opinions about the brain, many of which agree with each other. But then come some curious cases which tend to cast doubt on everything we take as “established fact.” Perhaps most notable is the case of the Boy With No Brain.

John Lorber is a British neurologist who studies people with hydrocephalus, a condition characterized by abnormally increased levels of cerebrospinal fluid in the brain. Most people with this condition do not live very long, or live with severe mental disabilities. Lorber found a student at Sheffield University in England who has an IQ of 126, is an honors math student, and has practically no brain at all as we understand it.

A CAT scan revealed that he had but a millimeter of cortical brain tissue, where the average is 4.5 centimeters. The rest of his brain is mostly cerebrospinal fluid, but he does seem to have some of the more primitive brain structures. This case is not totally rare among hydrocephalics - of the most extreme form of hydrocephela, in which 95% of the cranial cavity is filled with fluid, half of those affected are extremely mentally retarded, and the other half have IQs over 100.  He became known as the Boy With No Brain.

This is a controversial topic, to be sure. Many neuroscientists reject the findings for some reason or other. One objection is that the brain scans were not properly analyzed, and that the exact calculations for the size and weight of the brain for the student mentioned above were not done. Lorber is aware of the dramatic nature of his claim, and his reply to this objection basically sums up to saying: I'm not stupid, and I wouldn't say this without evidence.

If you want to read more about this, you can take a look at the infamously titled review of Lorber's and others findings in the journal Science, right here : Is Your Brain Really Necessary?

Another review of this and other cases of hydrocephalus : Where is Consciousness? I've Lost It!

Cases like this may instill feelings of doubt, insecurity, and that notion of “why am I studying this perhaps I should be a janitor.” But never fear, mysteries only leave more room for ground-breaking research and ideas. Let this be a lesson that science generally concerns itself with the “normal majority” and is every so often greatly tweaked by some rare exceptions.

There is a lot of progress being made in analyzing brain functions and activity, and new things are being discovered almost daily. Christof Koch is one of the foremost researchers of the neural correlates of consciousness. He worked for many years towards this end with Francis Crick, one of the DNA guys.

Recent developments have allowed us (humans) to look at the activity of a single neuron. This is pretty cool, because it brings us to a level of detail that was almost unimaginable before this decade. 

Here is a great lecture by Christof Koch in which he mentions this, as well as some of his recent work on this subject.

If you'd like to read more about his research, here is a paper he wrote with Francis Crick on the subject:  The Neural Basis of Consciousness

Here is another take on the NCC by a distinguished philosopher, David Chalmers : What is a neural correlate of consciousness?

For a detailed and thorough account of the current information about the NCC, check out this Scholarpedia article, curated by Christof Koch himself : Neural Correlates of Consciousness

An Overview of Brain Anatomy

Technically, there may be no known neural correlates of consciousness at this time that are agreed on by all researchers. However, several major brain areas have been grouped according to their general functions, with hundreds, probably thousands, of other structures tentatively associated with more specific processes. Our ideas about brain anatomy are a rough sketch at best, missing important details, but many structures have been commonly identified by many different researchers.

Here, we will take a look at some of the major divisions of the brain. Then the neocortex will be explored a bit more, because its kind of important.

The hindbrain: This is the oldest part of the brain, and it consists of the medulla, pons, and the cerebellum. It is sometimes referred to as the 'reptilian' brain, and seems to deal mostly with our basic survival needs. The structures of the hindbrain regulate autonomic bodily functions such as breathing, swallowing, digestion, and body posture. It also keeps an eye out for danger.

The midbrain: Consists mostly of the tectum, and is involved with processing sensory and motor functions. It connects the hindbrain with the forebrain. This structure, along with the hindbrain, is referred to as the brainstem. Not much is often said about the midbrain.

The forebrain: Consists of the thalamus, hypothalamus, and neocortex, which, along with 'lateral geniculate nucleus' is a candidate for “coolest name in the brain.” The thalamus is a relay station of sorts. It receives sensory information which it organizes and passes on to the appropriate areas of the neocortex. The hypothalamus is a very busy piece of brain that is best known for its role in maintaining homeostasis of the body. It is involved with blood pressure, eating, general arousal, rage, escape reflexes, pleasure, and much more.

The Neocortex: Or cerebral cortex. Or just cortex. Its the very newest part of the brain, and humans have the newest one still. The cortex has probably frustrated more researchers than any other. It is subdivided in many, many, ways (it requires long division), the most prominent being the separation into hemispheres, whose functions complement each other.

The left hemisphere: Is generally involved with activity on the right side of our bodies. In most people (but less left-handed people than right-handed people) this side of the brain is more actively engaged during language use (speaking, reading, etc..) than the right hemisphere. It is also more involved with conscious attention, logic, and sequential processing. It can kind of be thought of as the laser-focus aspect of the brain.

The right hemisphere: Is, on the other hand, generally involved with activity on the left side of our bodies. It is more involved (often called “better”) at non-verbal representation, spatial relations, and pattern recognition, such as faces. It seems to be proficient at parallel processing, seeing relationships and “the big picture.” It can kind of be thought as the floodlight aspect of the brain in contrast to the laser-focus aspect of the left hemisphere.

The hemispheres are connected through the corpus collosum, a thick band of nerve fibers that carry information between the left and right cerebral hemispheres.

Getting more specific, the cortex is also divided into the frontal, temporal, parietal, and occipital lobes. Each of these, remember, has a left and right hemisphere.

The Frontal lobe: Often thought of as the executive decision-maker because of its role in the higher cognitive functions such as planning for the future, emotions, language, and judgment. It is also involved with problem solving, attention, and social behavior.

The Temporal lobe: Highly involved with the processing of auditory and olfactory information. Also, learning, memory, and emotion are correlated with this area.  

The Parietal lobe: Involved with sensory and motor information processing, and the integration of the two. It handles much of the processing for our senses of touch, motion, and spatial representations.

The Occipital lobe: Is located at the very back of the brain and seems to be dedicated to processing visual information. This includes determining shapes, colors, sizes, locations, and sending this information to various parts of the brain.

Hopefully this has provided an overview of the major functional areas of the brain. Repeating the same functions across different areas was not a mistake; many functions are shared across many brain areas.

Seems almost simple, right? Match up our subjective, conscious experience with those areas of the brain that light up at the same time. Researchers can chip away at this task, and the mysteries of consciousness will dwindle and be described in obscure anatomical terminology.

However, within the realm of science, certainty is the devil. Next time, we'll take a look at the conundrum of the Boy With No Brain, as well as some modern research of the neural correlates of consciousness.

What does "Neural Correlates of Consciousness" mean?

This idea comes from a perspective that consciousness arises with brain processes.  This goes against the philosophy of mind-body dualism, which attempts to explain the mind and body as separate somethings.


The neural correlates of consciousness are those neuronal mechanisms, processes, and activities that are correlated with certain conscious experiences, such as seeing a color or feeling an emotion.  According to this view, every phenomenal mental state has a corresponding brain state.


The brain is a complex and interconnected system, with many processes running in parallel.  So, when looking for correlations with consciousness, we look for the minimal amount of neuronal activity associated with various aspects of consciousness.  Gathering empirical data is crucial for study of this nature, because it does not rely on philosophical or theoretical arguments.


Today, there are incredible methods and techniques for gathering information about the brain (while the person is still alive!) that are quite recent developments.  These brain scanning techniques can observe a person's brain as they have thoughts and experiences. There are several major types of brain scanning techniques:

Computed Tomography (CT) uses X-Rays that pass through the brain and

form an image that is measured on the other side. 
Dense tissues appear darker than less-dense tissues.

Positron Emission Computed Tomography (PECT) is similar to CT, but radiolabeled compounds that can be tracked are first injected into the brain of the subject.  When X-Rays are passed through the brain, the labeled compounds can be identified and tracked.  This can show blood flow, metabolic activity, and other processes.

Magnetic Resonance Imaging (MRI) amplifies the activity of certain protons in the
 brain.  The resulting image is created by measuring the time it takes for the protons to return to their original state.  The strength of the image depends on the density of the material.










Functional Magnetic Resonance Imaging (fMRI) is similar to MRI, but is used to study brain activity while the brain undergoes specific processes or tasks.
 














Professor Christopher Koch's Glossary of Terms:  This is a useful glossary of terms relating to the study of the neural correlates of consciousness.

Next time, we will take a look at some actual brain processes that have been correlated with conscious experiences.