Neuroscience and the Neuronal Correlates of Consciousness

Neuroscience and the Brain

Even the most enthusiastic neuroscientist will concede that the human brain is not much to look at: a 1.5kg cauliflower of grey, spongy matter. But despite their modest outward appearance, our brains are the most complex objects known to man, and still represent the greatest problem in biology: how the timed firing of electrical signals from neurons, along with glial cells and neurotransmitters, can give rise to something as remarkably abstract as our own consciousness.

With recent advances in the field of neuroscience, the way we think about the way we think is changing, and the quest for the physical basis of consciousness promises to be a voyage of discovery as fascinating as the quest for the structure of DNA in the early 1950s. But what exactly are the problems facing neuroscientists, and how are these being solved today?

Defining Consciousness and Awareness

Perhaps the first issue is in defining consciousness itself. As human beings, we experience the world. When light of a certain wavelength hits the cone photoreceptors of our retina, we experience the sensation of seeing “red”, for instance, and we have feelings that correspond to this experience.

We are also probably not the only animals who experience the world in this way. Experimenting (humanely) with chimpanzees and dolphins has demonstrated that they are capable of complex, abstract tasks such as recognising themselves in mirrors (Gallup, 1970) and planning future actions (BBC), activities which should be impossible without some form of consciousness, or inner mental life.

Even the humble fruitfly has demonstrated that it is capable of complex behaviours involving choice (Heisenberg and Wolf, 1984). As such, Descarte’s idea of there being a “threshold of consciousness” over which only humanity has stepped has begun to sound as outdated as the concept of a geocentric universe.

Are Computers Conscious?

However, a neat sliding scale of consciousness also has its faults. Everyone has experienced what happens when a computer finds a fault in its hardware: you will likely receive a cryptic error message, or simply the “blue screen of death” as the damaged system struggles to function. But the idea that computers sense this line of code as analogous to pain, or that they experience the world on any level at all, can be discarded fairly quickly.

That is not to say that this suggestion does not have its proponents. Some scientists, like David Chalmers of the University of Arizona, postulate that all systems capable of processing information, even digital systems, are conscious in some sense, if only on a rudimentary level. Chalmers does concede, however, that it would probably not feel like much “to be a thermostat” (Koch & Krick).

Were this theory correct, it would suggest that our spinal columns, for instance, along with many parts of our brain and even the 100 million or so neurons found in the intestinal wall, could themselves be conscious. After all, they, too, process enormous amounts of information every second. If they are, of course, they are certainly not telling us about it!

Studying the Brain

One problem for scientists is that in-depth study of the brain is necessarily an invasive and life-threatening procedure. Much has been learnt from studies involving electrodes measuring the brain’s electrical field from outside the skull, but this is as problematic as trying to learn about the structure of the ocean by studying its waves.

As such, a vast majority of recent developments in the science of our own minds comes from what happens when they go wrong. Patients suffering massive epileptic seizures must undergo complicated surgery to have electrodes placed inside their brain in order to locate the troublesome tissue causing their seizures. This gives scientists a unique opportunity to study the way the brain works, and in particular how its workings give rise to consciousness.

The Clinton Neuron

One remarkable discovery has involved a specific neuron found in a seizure patient that fires whenever the subject sees a picture of former US president Bill Clinton. The patient was shown photographs of other white-haired men, other former presidents and hundreds of random control pictures, none of which elicited a response. Every time Mr. Clinton entered the subject’s field of view, the electrical readings from this single neuron spiked.

The implications of this are enormous, since it places the firing of neurons right at the start of the chain of mechanisms that create consciousness. When this neuron and the possibly hundreds of other “backup” duplicates fire, they somehow start a series of events that results in the patient recognising a face. But the question remains: how does this binary system of neurons either firing or remaining dormant create the almost infinite intricacies of our minds?

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The Biology of Belief by Bruce Lipton, Ph.D.

Lipton introduces in his book The Biology of Belief what he calls the new biology against the dogma of contemporary biology: DNA controls biological life. Ever since Darwin suggested in his 1859 book, The Origin of Species that “hereditary factors” passed from parent to child was the driving force for evolution, biologists were obsessed with the search for the hereditary mechanism that controlled life.

When the DNA structure and function were unveiled by James Watson and Francis Crick, the world was being taken by the rosy prospects of discovering the secrets of life. The power of DNA has grown from determining our physical characteristics, to controlling our emotions and behavior. The survival of the fittest individual is reflected in the survival of the fittest genes.

The New Biology

Against this traditional reductionist’s view of a competitive life, Lipton presents scientific evidences, including underrated old findings and exciting recent discoveries, that life is about co-operative harmony not only with other life forms, but also with the physical environment.

By expounding why and how “smart” cells, as Lipton calls them, can teach us about human mind and body, Lipton replaces the biological myths with the following conclusions:

  • Genes do not control biology in a fatalistic sense.
  • Cell membrane, instead of the DNA-containing nucleus, is the true brain of a cell.
  • The environment plays a decisive role in the behavior of cells despite the genetic codes.

How Thoughts Control Life

By explaining why quantum physics is relevant to biology, Lipton points out that the body, like the universe, is one indivisible whole with interchangeable energy and matter. Thoughts, the mind’s energy, directly influence the physical brain, long recognized as an electrical organ. The brain controls body’s physiology by activating or inhibiting proteins which in turn change the micro-environment of the cells and thus control cell functions.

Such biological consequences of thoughts or beliefs lead Lipton to call his book The Biology of Belief. The placebo effect is a prime example Lipton uses to explain the effects of mind over body. However, Lipton points out that reality is complicated by the operation of conscious and unconscious thoughts. The mere thinking of positive conscious thoughts against the more powerful unconscious programming does not change anything.

Lipton continues to illustrate the biological basis of negative thoughts, mostly related to the physiology of the flight and fight response triggered by fear. Such protective mechanism inhibits growth to conserve energy and resources for survival. The growth-inhibiting mode has profound effects on human development as far back as the time of conception. Lipton devotes a whole chapter called “Conscious Parenting: Parents as Genetic Engineers” about the importance of creating a healthy and happy environment – biologically, emotionally and physically – for the unborn children and infants.

What Lipton does not elaborate much is how an adult can undo the self-sabotaging unconscious programming to create a fulfilled life although he does mention in the Addendum that PSYCHE-K has helped him undo his self-limiting beliefs. The Biology of Belief is more a scientific exploration about how thoughts control life, rather than a self-help book with practicable steps to change one’s life.

How Do Bacteria Make People Sick?: Bacterial Pathnogenicity, Virulence Factors and Infectious Disease

In order to cause disease, potentially harmful bacteria must first enter the body, usually through breaks in the skin, penetrating the mucous membrane or colonizing the gastrointestinal (GI) tract. This is considered infection, when bacteria breech the first line defenses of the body.

Bacterial disease starts with infection, but infection does not always result in disease. Many bacteria are beneficial. And even when pathogens infect the body, the immune system may be able to eliminate the infection before symptoms of disease occur.

Bacterial Pathogenicity and Virulence

To cause disease, bacteria must be present in sufficient numbers. But what is it about bacteria that make an infected person ill? Disease is not merely caused by the presence of microbes.

Pathogenicity (path-o-jen-ISS-ity) refers to a microbe’s ability to cause disease, and some microbes are more pathogenic—better able to cause disease—than others. The degree of a microbe’s pathogenicity is considered its “virulence.” For example, highly virulent bacteria frequently cause disease, whereas less virulent bacteria may only cause disease when present in large numbers or within hosts that have weakened immune systems.

Many pathogenic, or disease-causing bacteria have special weaponry, traits that enable them to infect and damage host tissue. These disease-causing traits are called “virulence factors”. The following sections describe different types of virulence factors.

Adhesion Factors, Glycocalyces and Biofilms

Once bacteria get into the body, they must be able to stick to the host’s cells in order to increase in number. Bacteria that are able to stick to host cells have special structures or chemicals, collectively called adhesion factors. These adhesins are found on bacterial cell extensions, such as fimbriae and flagella, and also on glycocalyces, a sticky layer surrounding some bacterial cells that enable bacteria to stick to surfaces and to each other in biofilms. For example, the inside of the mouth and teeth are covered with a sticky bacterial biofilm, particularly in the morning, before brushing, because bacteria have been multiplying in the mouth throughout the night.

Bacterial Extracellular Enzymes

Some pathogenic bacteria are able to produce and secrete enzymes that compromise cell structure of the host and enable the bacteria to work their way further into the body.

Bacterial Toxins

Bacteria may also produce toxins that cause damage to host cells either directly, by destroying tissue, or indirectly, by triggering an intense or prolonged host immune response. Bacterial toxins fall into two general categories based on their position relative to the cell that produces them; exotoxins, which are secreted by bacteria, and endotoxins, such as lipid-A, which are part of the Gram-negative bacterial cell.

Evading Host Immune System

The human immune system has special white blood cells called phagocytes, which search out, engulf and digest invading pathogens. The sooner a pathogen can be eliminated from the body, the less damage it will have the opportunity to cause. However, bacteria have developed means of evading phagocytes.

The bacterial capsule, a type of glycocalyx, can help a bacterium hide from the immune system. This coating is often made of chemicals that are found in the human body, and that don’t trigger an immune response.

Other bacteria produce chemicals that prevent them from being digested once engulfed by a phagocytic white blood cell, allowing the bacteria to live and reproduce inside the host cells designed to eliminate them. Other antiphagocytic chemicals can prevent bacteria from being engulfed by white blood cell, or can even destroy white blood cells.

How We Hear – Travel Along a Sound Wave from Ear to Brain

Hearing happens in an instant – quick transformations to energy until the movement of molecules is meaningful to a listener. It’s not magic, but the small size and complexity of shapes, movements and structures involved in energy transformation makes the process seem magical. To be able to hear beautiful music or birdsong in spring or mother’s voice is an awesome act of nature.

To put it very simply, sound is a type of energy and to get it from outside the head to the place in the brain where it can be “heard,” sound energy has to be sent from the microphone to the amplifier, along wiring, and on to the translating device.

Outer Ear

The ear that seen on the side of the head acts like a satellite dish that catches waves of sound. This outer ear is shaped to funnel and swirl the sound of energy made when molecules move as they are displaced by air, water or solid objects. The displacement forms waves that flow into the ear hole. In the tunnel that leads to the ear’s complex structures, the molecules move closer together and become louder.

On to the Middle and Inner Ear

Just about an inch past the ear that is seen outside the body and inside the ear hole, sound energy beats on the ear drum. The rhythm is taken up and passed along by three very tiny bones. In the middle ear compartment, the mechanical action of the bones amplify the air waves.

Now in the form of mechanical energy, the wave moves on to another tiny membrane that leads to the shell-shaped and fluid-filled inner ear. In the shell, called the cochlea, sound energy swims through the fluid and strums across teeny, tiny hairs that bend and snap.

On to the Brain

Energy fires neurons bundled into the nerve of hearing, the auditory nerve. The nerve’s long wires or axons zings energy forward to lower brain structures until the energy in analyzed in the cortex of the brain.

Now, if anything is really magical, it’s this part of hearing. How does that electrical energy get processed into meaningful words and sentences? Researchers are just beginning to understanding how the brain works and new discoveries are revealing more and more amazing information every day.

Sound Traveled, Energy Converted, Hearing Accomplished

Hear that? Fast, wasn’t it?

To summarize, the sound energy from the air is captured by the ear, knocks on the ear drum, is amplified by the bones of the middle ear, swims into the waters of the inner ear where waves wash over tiny hairs, which snap an electrical message along nerve wiring to the brain. The energy zaps to the cortex where analysis takes place and a response unfolds next.

Although it happens in an instant, it’s not magic. But hearing is still rather miraculous … or magical … don’t you agree?

Long Point Waterfowl A Leading Researcher: Ontario Organization Studies Waterfowl Issues

Based in Long Point, Ontario, Long Point Waterfowl is a non-profit, non-government organization dedicated to waterfowl and wetland-related research, conservation and training. Long Point Waterfowl also promotes Canada’s outdoor heritage.

Long Point Waterfowl was originally formed as Long Point Waterfowl and Wetlands Research Fund in the 1980s. Conservation-minded hunters at Bluff’s Club, a private hunting club on Long Point, were behind the efforts. Funding is still mainly from the Bluff’s Club members, but is also supported by Ducks Unlimited Canada, Waterfowl Research Foundation, Syndenham Conservation Foundation and the Ontario Federation of Anglers and Hunters.

The headquarters for Long Point Waterfowl is at Bird Studies Canada in Long Point, which is also the administrator.

The primary purpose of Long Point Waterfowl is to study the staging ecology and requirements of waterfowl on the lower Great Lakes. Long Point Waterfowl scientists also monitor trends in the distribution and abundance of waterfowl, research waterfowl habitat and provide information regarding waterfowl management.

Research results are published in scientific journals and presented at leading symposiums.

Long Point Waterfowl Research Centre

A former Ontario Youth Ranger Camp, Long Point Waterfowl leased this facility near Turkey Point as a place to host students and hold youth programs.

Youth Involvement In Conservation

One of the more unique events at Long Point Waterfowl is its young biologists workshop. This annual summer event is aimed at teenagers who are thinking of a future career as a biologist, conservation officers, wildlife technician or other related fields.

Participants learn about banding ducks, habitat, wildlife ecology, the role of hunting in conservation and a wide variety of other topics. The multi-day event includes meals and a stay at the Long Point Waterfowl Research Centre. Participants also learn about the educational requirements of future careers and hear from professionals in those fields.

Long Point Waterfowl also hosts a multi-day event where teenagers can stay at the centre and take all the training for their hunting certification.

Fund executive director Scott Petrie is also a teacher at the University of Western Ontario and sees that the students coming in don’t have the same background in the outdoors.

“Within our profession, people aren’t getting the training,” he said. “When I get a 22-year-old, they’re behind the eight-ball because they don’t have the passion.”

Research Projects at Long Point

Tundra swans are regular visitors to Long Point on their migration route from wintering grounds on the Atlantic seaboard to the high Arctic breeding grounds. Since little was known about these long-distant migrants, one of the first projects Petrie undertook was a satellite tracking study to learn more about tundra swan migration routes.

This was groundbreaking research, as such a study had never been undertaken with tundra swans in North America.

Resulting research has shown much about the swans, how much time they spent on migration, feeding habits along the way, when they arrive in the Arctic and much more. A map of the migration is available on Long Point Waterfowl’s web site

When a problem began to appear that numbers of lesser and greater scaup were declining relative to the health of other waterfowl species, Long Point Waterfowl again turned to satellite transmitters to learn more about the birds. This effort is still ongoing and is part of a cooperative venture between several research organizations investigating the problem.

Another major research initiative looked at the historical abundance and distribution of phragmites at Long Point. This tall grass with feather-like tops, an invasive species, was rapidly expanding at Long Point and displacing native vegetation. Research showed it is less preferable as waterfowl habitat than native vegetation. Other researchers have since identified it is a problem at other locations in Southwestern Ontario.

A current study is looking at the expanding population of Greater Sandhill Cranes in Ontario and the impact on agriculture.