Consciousness has been defined as current awareness of our mind about such things as our sensations, perception, memories, feelings and fantasies. Some of these, which our conscious mind wants to be kept hidden, are stored in our unconscious mind.
Consciousness is an ability of humans to perceive reality and report it through expressions. It is a subjective experience and may differ among individuals.
Our conscious mind experiences a unique sensation when we observe something with our sense organs. It is an experience which is unique to each person and cannot be expressed verbally. In philosophy, they use the term ‘qualia’, defined as individual instances of subjective, conscious experiences.
One cannot verbally explain the colour red to a person born blind or the sound of music to a born deaf person. While we perceive them as unified properties of outside world, they are products of our mind (Chalmers, 1995).
Research indicates that our consciousness of something lags almost third of second behind the event itself (Dehaene, 2014).Brain imaging studies indicate that language processing areas are directly involved even in the simplest discriminations of basic colours (Kastrup, 2018).
A study conducted by the Massachusetts Institute of Technology (2012) on anaesthesia-induced unconsciousness indicated that when the participants lost consciousness, their brain activities began to show regular oscillation between nstates of activation and deactivation. The deactivated or silent periods occurred at different times in different brain regions, which resulted in interruption of communication between regions.
Consciousness comes and goes every day when we wake up and go to sleep. We may lose consciousness by administration of anaesthetics or due to brain injury. All of these lacks subjective experience* (Demertzi and others, 2019).
*(It would be pertinent to cite here my personal experience. I was to undergo a minor surgery and lying on the table in the operation theatre. It was 5 pm on the wall clock. The anaesthetist put a mask on my face and released anaesthesia. His assistant asked him, “But where is the surgeon?” I became conscious. Why were they giving me anaesthesia when the surgeon had not arrived? I thought of taking out my mask but became unconscious. When I awoke, I found myself in a bed in the ICU. I remembered my suspicion and asked the nurse, “What’s the time.” She told me it was 5.40 pm. I felt assured there was no delay. When I asked the surgeon, he confirmed that he was in the antechamber wearing masks, aprons and preparing to undertake the surgery. Was it not a subjective experience?)
Can quantum physics explain our brain’s ability to think?
From consciousness to long-term memory, the human brain has peculiar computing abilities, which could possibly be explained by fuzziness of quantum theory (Brooks, 2015).
Fisher (2015) used the term ‘quantum cognition’ and explored the possibility of quantum processing in the brain. He suggested phosphorus as the unique biological element with a nuclear spin that can serve as a cubit for putative quantum processing in the brain.
Oxford mathematician Roger Penrose collaborated with Arizona-based anaesthetist Stuart Hameroff to suggest ‘The Orch-OR (Orchestrated Objective Reduction) theory’ (Hameroff and Penrose, 2014) based on quantum mechanics. The theory proposes that quantum computation in the brain microtubules accounts for our consciousness. Orch-Or links consciousness with fundamental space-time geometry and concludes that it plays an intrinsic role in the universe.
Christof Koch, chief scientist and president Allen Institute of Brain Science (alleninstitute.org,2019) says humans have approximately 86 billion neurons and 100 trillion connections or synapses. It is a daunting task to understand the details of how these cells work, let alone how they come together to make up our sensory system, our behaviour or our consciousness.
Human consciousness is supported by a dynamic complex pattern of brain signal coordination. Redinbaugh and others (2020) conducted functional MRI and electrophysiological studies on monkey brain and suggested that ‘Consciousness depends on large-scale thermo cortical and cortico-cortical interactions. Consciousness also depends on deep layer neurons providing feedback to superficial layers.’
Recently, backed by Koch (2019), two concepts on consciousness are going to be tested under a $20-million project. Brain activity of two groups of volunteers would be scanned while performing a series of cleverly-designed tasks targeted to find out brain’s physical origin of conscious thought.
The two theories are:
i) Global Work Space (GWS) theory of Stanislas Dehaene of College de France, Paris
ii) Integrated Information (IIT) theory of Giulio Tononi of the University of Wisconsin, Madison, backed by Koch.
According to GWS, consciousness arises when we integrate and segregate information from multiple sources such as sense organs and combine it into a piece of data in a global workspace within the brain. The workspace itself creates consciousness and acts as a motivational whip to drive actions. Brain-imaging studies in human suggest that the prefrontal cortex acts as central processing unit similar to a computer.
According to IIT, consciousness arises from intrinsic interconnectedness of brain’s network. When neurons connect in the ‘right’ way under ‘right’ circumstances, consciousness naturally emerges to create the sensation of experience. According to IIT, this happens in the back of the brain where neurons connect in a grid-like structure and would be able to support this capacity.
The theories will be tested in six different labs across the world, where 500 people will be subjected to three different types of brain recordings (MRI, EEG, ECoG-a type of EEG with electrodes directly placed on the brain).
Several journals have assured to publish the results.
(Dr Mitra, a former Dean and Professor, Chemistry and Biochemistry, OUAT, Bhubaneswar, is a researcher and author of several scientific publications and books. All the references quoted are available in the internet. gnmitra@gmail.com)