One of the supposedly “big questions” that continues to baffle scientists is the nature of consciousness.

Some of the biggest names in science, including three Nobel Prize winners, Erwin Schrodinger (1933 Nobel), Francis Crick (1953 Nobel) and most recently Roger Penrose (2020 Nobel) took on the question of what was the nature of consciousness, not as part of their Nobel-winning efforts, but as part their broader interests.

Curiously enough, all three were physicists and Schrodinger and Penrose were accomplished mathematicians.

Both Schrodinger and Penrose thought of consciousness as part of the universe — indeed. Schrodinger held that consciousness was in some manner, a quantum phenomenon. Penrose suggested that consciousness made up as much as one third of the universe.

Francis Crick, on the other hand, considered consciousness to be a property of the brain and set about trying to find the “seat” of consciousness. He failed in several decades of studies.

Oliver Sacks, a neurologist, neuroscientist and friend of Crick, dismissed efforts to understand consciousness as fruitless.

These days, the nature of consciousness is hotly debated by several competing groups, with no consensus or clarity emerging in the debates between them.

But whatever the arguments the subject has attracted the attention of theologians, philosophers, psychologists, neurologists and neurosurgeons and no surprise in this age, the artificial intelligence universe raises new questions.

Is AI conscious, sentient and possess cognitive powers equal to or exceeding humans?

Within the domains of clinical neurology, neurosurgery, neuroscience, epilepsy, anaesthesia and neuroimaging, there are well-established correlations for consciousness.

For example, small lesions such as an intracerebral hemorrhage involving the thalamus may expand to compress the adjacent diencephalon and upper brain stem, leading to drowsiness followed by coma.

Other lesions, whether an ischemic stroke or trauma affecting the same region, are commonly associated with a similar loss of consciousness.

A seizure may begin in the medial temporal lobe and, with spread, lead to loss of consciousness and a grand mal seizure. Or, should the cardiac output suddenly drop because of an arrythmia, the whole brain may be deprived of blood and oxygen and the patient drop unconscious to the floor. 

The point is that consciousness may be lost if critical areas in the upper brainstem and adjacent diencephalon or perhaps far more extensive areas of the brain are affected. And there’s no shortage of drugs that alter awareness and consciousness.

In the day-to-day world of our experience, a more useful way for me to think about consciousness is awareness.

For example, in this moment, I’m aware of my fingers typing out letters and words, the faint sound of air passing through the room vent and the top of my desk cluttered with papers, books and pens, but little else — certainly nothing of what’s going on my innards a few hours after my last meal and all the other sensory activity, which must be going on but of which I’m mercifully unaware.

In that sense, I’m subjectively and selectively conscious, but certainly not of the universe or anything else other than my running thoughts, which seem to be almost synchronous with my typing. 

Focusing on a small bit of what’s going on is our salvation, because if we were fully aware of all the neural activity in our nervous system and other systems and organs, we would be helplessly overwhelmed in no time. 

So, I can describe a selective, very tiny fraction of what’s going on in my brain but nothing else. And when I’m asleep, I might dream, most of which I won’t be aware of, but sometimes am, in that twilight awareness between sleep and becoming fully awake. 

What about AI? Are current advanced AI systems aware of what’s going on inside them as they go about their business of grasping whatever questions we might pose, search for whatever related information they might possess and compose an appropriate response to us? 

A good way to answer that question is to ask the same of ourselves: are we aware of all the goings on in our brain as we respond to some question?

My answer is no, although I’m aware of prompts and somehow, as I type this, some sort of answer comes out in my thoughts and in typewritten form.

Put that way, AI is as aware as we are and perhaps more. 

A related hotly debated question is whether AI is intelligent and, more provocatively, as intelligent or more so than us — to which my answer would be similar.

For sure AI is intelligent, very much so, and given its capacity to grow and handle much larger databases, will, if not now, then soon, develop general intelligence the equal of teams of humans, not just you and me. 

Finally, is AI sentient? If not, it’s well on the way to sentience, just as the character Data was found to be in “Star Trek: The Next Generation” in the 1990s, when that question was asked by some scientists and lots of science-fiction writers. 

Have I confused you? Probably, but not intentionally. I’m in the same boat. 

Dr. William Brown is a professor of neurology at McMaster University and co-founder of the InfoHealth series at the Niagara-on-the-Lake Public Library.