Consciousness. A scientific inquiry

 Blog:

Consciousness.

A Scientific Inquiry.

P.K.Ghatak, MD

No.62.

A flood of research papers was published recently on Consciousness. Behind the enthusiasm is a hard competition for leading a race to equip Robots with consciousness.

In the past, such interests were generated when Neuroimaging technology was developed and particularly the “functional MRI” was introduced. The next wave of research papers followed after the publication of Dr. Jane Goodall's research on the social interactions and behavioral characteristics of the chimpanzees. Dr. Goodall discovered that Chimpanzees use tools, possess complex social behaviors and exhibit emotions like us.

Many researchers inspired by Goodall, began working with subjects not limited only to the primates but also to birds, insects and even molluscans. One could recall Paul, the octopus who correctly picked the winning jersey of teams, 12 out of 14 times, when World Cup (soccer) was played in 2010 in Germany.

What is consciousness.

In the medical field, the Anesthesiologists are rendering patients unconscious for the surgeon's knife and then waking them up. To learn about consciousness, it is a good place to begin.

The American Society of Anesthesiologists define consciousness as a state of wakeful awareness involving the capacity to process information from the surroundings and demonstrate purposeful responses to stimuli.

From the early days of neurology, we learned two types of actions: 1, Reflex actions where only local neuronal circuit is involved without any influence of higher centers.2, Voluntary action requires a nerve center to analyses incoming sensation, localize its origin, deduct the possible causes and formalize best action and give order to muscle to act.

Going back to Paul the octopus – was Paul acted similar to a voluntary action or just in a random way. To determine that - the neuroimaging can solve which can differentiate between the two. If the higher brain centers were involved, the center would have lighted up in the functional MRI scan.

In an elegant experiment conducted by the scientists at Ruhr University, Germany. They placed a rooster in a chickenware enclosure. A shadow of a hunting eagle was projected on the roof of the box. The experiment ran three times under three different conditions.

In the No.1 run, the rooster was alone.

In the No.2 run, the roosters saw many chickens outside through the chickenware box.

In the No.3 run, the rooster saw his reflections on mirrors placed all around within the box.

In the first instance, the rooster sounded an alarm to warn his fellow chicken then took defense action. In the 2nd and 3rd times the rooster did not sound an alarm but took defensive action.

In the second run of the experiment, the rooster realized that other chickens outside the box were at risk and on the 3rd run, the rooster recognized the reflection on the mirrors of his own.

The brains of birds are structured differently than humans. In place of the cerebral cortex the birds possess a Neopallium Coaudolaterale. 1.(see foot note)

This experiment satisfied all the elements set forth to call an action as a conscious action. If creatures other than humans also possess consciousness, then where does consciousness resides.

In Human:

The location of consciousness in the brain of humans has changed and continues to evolve. At present two locations in the cerebral cortex are prime locations. The posterior-occipital areas, including parts of the temporal and parietal cortices and prefrontal cortex. The posterior part of the cortex probably deals with sensory input and its interpretation, and the anterior part of the cortex is responsible for formulation of action and execution of the response. These two centers are interconnected and also connected with thalamus. The role of thalamus is modulatory rather than primary action. Most researchers believe, when information is widely distributed over the brain by the interconnecting network, then it reaches the conscious level. Anatomically these interconnecting neuronal networks are called Tegmentum of the midbrain and the upper part of the hind brain. As shown in the diagram.

The Anesthesiologists take a conscious person and put him through 3 stages- induction of anesthesia, maintenance of the unconscious stage and recovery of full consciousness. The arousal states reflect the overall state of activities in the brain. Conscious awareness is a more dynamic and complex process involving several cerebral networks and centers.

Scientific inquiry deals with verifiable facts. The topic Consciousness was initially the religious domain. One can find many detailed discussions on consciousness in Sanatan Dharma (Hindu religion) and Buddhist Book of religious discourses. Much later the Philosophers tried their hands and now science is trying to settle it with verifiable evidence. This short essay is only for someone interested in science.

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Foot note, 1, In human brain these are caudate nucleus and palladium, part of the prefrontal cortex.