Nature and Characteristics of Consciousness

A fundamental property of the mind is the ability to mentally represent the world in order to simulate possible effects of behaviour.¹ This occurs in three steps.

First, sensory stimuli is converted into neural patterns. Then, they are re-constructed using different symbols, creating a meaning-embodying representation of the world. Finally, mental plans are converted into muscular activities.

According to Harry Jerrison, paleoneurologist, the main function of the central nervous system is to construct mental models of reality. The ability to simulate and elaborate on these models constitutes biological intelligence.

Cognitive neuroscience data indicate that both the world and the self are a construction of our brain, which creates the illusion that they are real.²

There are many philosophical theories on the ontological nature of consciousness as detailed in the table³ below alongside renowned proponents.

Characteristics of Human Consciousness

According to the psychologist, Franz Brentano, human consciousness always involves a content concerning the world, the body or the mind itself. Thus, consciousness is always awareness of something.⁴ This characteristic is called intentionality.

Psychologist, Edving Tulving, has proposed three states of consciousness: anoetic, noetic and autonoetic.⁵ Most of the mental activity involved in linguistic and cognitive processing seems to be carried out on a non-conscious, or anoetic, level. ⁶

The ability to recognise and distinguish concepts is a part of the noetic form of consciousness. The ability to remember events in one’s life and imagine different experiences is involved in the autonoetic level of consciousness. This also involves being aware of the present and past memories simultaneously.

Neuroscientific Theories of Consciousness

According to biologist, Gerald Edelman, primary (noetic) consciousness is a sort of “remembered present”– a picture in the mind’s eye of the immediate past.

What distinguishes human consciousness from that of non-humans is autonoetic, or higher-order, consciousness. It facilitates construction of personal identity, self-awareness dependent on one’s linguistic and cultural background, and the ability to generate a model of self that extends across time.

Edelman believed that human self-awareness emerges from the massive amounts of interactions between neuronal maps in the brain.

Another theory of consciousness is that of integrated information by Tononi who suggests that phenomenal consciousness depends on the wealth of integrated information in the brain.

He developed a measurement to quantify the level of integrated information in the brain during different states of consciousness. The measurement involves delivery of magnetic pulses via Transcranial Magnetic Stimulation (TMS) and the simultaneous recording of the evoked brain electrical activity (via Electroencephalography, EEG) during waking, sleep and dream states. ⁷

If the system is integrated, the magnetic pulse can diffuse to multiple cortices in the brain. In states of consciousness, such as slow-wave sleep or anesthesia, involving less brain activity, the pulse diffuses less in the brain as the cortices are more segregated.

Scientifically studying the origin and evolution of consciousness requires knowledge and data from many sources: studies of consciousness development in children, studies of different states of consciousness like dreaming and hypnosis, neurological analyses of people with impaired brains, gauging effects of psychotropic drugs on consciousness, and studies of consciousness in animals.

References:
1. Craik, 1943
2. Frith, 2007; Libet, 2006
3. Fabbro, 2019
4. Bodei, 2015
5. Tulving, 1985, 2002, 2005
6. Dehaene, 2014
7. Fabbro, 2019