Consciousness, at its simplest, is awareness of internal and external existence. However, its nature has led to millennia of analyses, explanations and debate by philosophers, theologians, and all of science. Opinions differ about what exactly needs to be studied or even considered consciousness. In some explanations, it is synonymous with the mind, and at other times, an aspect of mind. In the past, it was one's "inner life", the world of introspection, of private thought, imagination and volition. Today, it often includes any kind of cognition, experience, feeling or perception. It may be awareness, awareness of awareness, or self-awareness either continuously changing or not. The disparate range of research, notions and speculations raises a curiosity about whether the right questions are being asked.
Examples of the range of descriptions, definitions or explanations are: simple wakefulness, one's sense of selfhood or soul explored by "looking within"; being a metaphorical "stream" of contents, or being a mental state, mental event or mental process of the brain.
The problem of definition
About forty meanings attributed to the term consciousness can be identified and categorized based on functions and experiences. The prospects for reaching any single, agreed-upon, theory-independent definition of consciousness appear remote.
The dictionary definitions of the word consciousness extend through several centuries and reflect a range of seemingly related meanings, with some differences that have been controversial, such as the distinction between 'inward awareness' and 'perception' of the physical world, or the distinction between 'conscious' and 'unconscious', or the notion of a "mental entity" or "mental activity" that is not physical.
The common usage definitions of consciousness in Webster's Third New International Dictionary (1966 edition, Volume 1, page 482) are as follows:
awareness or perception of an inward psychological or spiritual fact; intuitively perceived knowledge of something in one's inner self
inward awareness of an external object, state, or fact
concerned awareness; INTEREST, CONCERN—often used with an attributive noun [e.g. class consciousness]
the state or activity that is characterized by sensation, emotion, volition, or thought; mind in the broadest possible sense; something in nature that is distinguished from the physical
the totality in psychology of sensations, perceptions, ideas, attitudes, and feelings of which an individual or a group is aware at any given time or within a particular time span—compare STREAM OF CONSCIOUSNESS
waking life (as that to which one returns after sleep, trance, fever) wherein all one's mental powers have returned . . .
the part of mental life or psychic content in psychoanalysis that is immediately available to the ego—compare PRECONSCIOUS, UNCONSCIOUS
The Cambridge Dictionary defines consciousness as "the state of understanding and realizing something." The Oxford Living Dictionary defines consciousness as "The state of being aware of and responsive to one's surroundings.", "A person's awareness or perception of something." and "The fact of awareness by the mind of itself and the world."
Philosophers have attempted to clarify technical distinctions by using a jargon of their own. The Routledge Encyclopedia of Philosophy in 1998 defines consciousness as follows:
Consciousness—Philosophers have used the term 'consciousness' for four main topics: knowledge in general, intentionality, introspection (and the knowledge it specifically generates) and phenomenal experience... Something within one's mind is 'introspectively conscious' just in case one introspects it (or is poised to do so). Introspection is often thought to deliver one's primary knowledge of one's mental life. An experience or other mental entity is 'phenomenally conscious' just in case there is 'something it is like' for one to have it. The clearest examples are: perceptual experience, such as tastings and seeings; bodily-sensational experiences, such as those of pains, tickles and itches; imaginative experiences, such as those of one's own actions or perceptions; and streams of thought, as in the experience of thinking 'in words' or 'in images'. Introspection and phenomenality seem independent, or dissociable, although this is controversial.
Many philosophers and scientists have been unhappy about the difficulty of producing a definition that does not involve circularity or fuzziness. In The Macmillan Dictionary of Psychology (1989 edition), Stuart Sutherland expressed a skeptical attitude more than a definition:
Consciousness—The having of perceptions, thoughts, and feelings; awareness. The term is impossible to define except in terms that are unintelligible without a grasp of what consciousness means. Many fall into the trap of equating consciousness with self-consciousness—to be conscious it is only necessary to be aware of the external world. Consciousness is a fascinating but elusive phenomenon: it is impossible to specify what it is, what it does, or why it has evolved. Nothing worth reading has been written on it.
A partisan definition such as Sutherland's can hugely affect researchers' assumptions and the direction of their work:
If awareness of the environment . . . is the criterion of consciousness, then even the protozoans are conscious. If awareness of awareness is required, then it is doubtful whether the great apes and human infants are conscious.
Many philosophers have argued that consciousness is a unitary concept that is understood by the majority of people despite the difficulty philosophers have had defining it. Others, though, have argued that the level of disagreement about the meaning of the word indicates that it either means different things to different people (for instance, the objective versus subjective aspects of consciousness), that it encompasses a variety of distinct meanings with no simple element in common, or that we should eliminate this concept from our understanding of the mind, a position known as consciousness semanticism.
WikiIs Consciousness a Fundamental Quality of the Universe?
Jun 14, 2019 by The Conversation
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Scientists have long been trying to understand human consciousness — the subjective ‘stuff’ of thoughts and sensations inside our minds. There used to be an assumption that consciousness is produced by our brains, and that in order to understand it, we just need to figure out how the brain works. But this assumption raises questions. Apart from the fact that decades of research and theorizing have not shed any significant light on the issue, there are some strange mismatches between consciousness and brain activity.
Scholars argue that consciousness is a fundamental quality of the Universe. Image credit: NASA / ESA / JPL-Caltech / STScI / Sci-News.com.
Scholars argue that consciousness is a fundamental quality of the Universe. Image credit: NASA / ESA / JPL-Caltech / STScI / Sci-News.com.
As the neuroscientist Giulio Tononi has pointed out, brain cells fire away almost as much in some states of unconsciousness (such as deep sleep) as they do in the wakeful conscious state.
In some parts of the brain, you can identify neurons associated with conscious experience, while other neurons don’t seem to have any affect on it.
There are also cases of a very low level of brain activity (such as during some near death experiences and comas) when consciousness may not only continue, but even become more intense.
If you held a human brain in your hand, you would find it to be a soggy clump of gray matter, a bit like putty, weighing about 1.3 kg. How is it possible that this gray soggy stuff can give rise to the richness and depth of your conscious experience? This is known as the ‘hard problem’ of consciousness.
As a result, many eminent philosophers (such as David Chalmers and Thomas Nagel) and scientists like Christof Koch and Tononi have rejected the idea that consciousness is directly produced by brain processes. They have turned to the alternative view that it is actually a fundamental quality of the Universe.
This might sound far fetched, but think about the other ‘fundamentals’ in the Universe we take for granted, such as gravity and mass. Consciousness would have the same status as those.
Fundamental explanations
One of the reasons I’m in favor of this approach is that the idea of consciousness as a fundamental quality offers elegant solutions to many problems which are difficult to explain using the standard scientific model.
First, it can explain the relationship between the brain and consciousness. The brain does not produce consciousness, but acts as a kind of receiver which ‘picks up’ the fundamental consciousness that is all around us, and ‘transmits’ it into our own being.
Because the human brain is so sophisticated and complex, it is able to receive and transmit consciousness in a very intense and intricate way, so that we are (probably) more intensely and expansively conscious than most other animals.
One of the arguments for assuming that the brain produces consciousness is that, if the brain is damaged, consciousness is impaired or altered. However, this doesn’t invalidate the idea that the brain may be a receiver and transmitter of consciousness. A radio doesn’t produce the music that comes through it, but if it is damaged, its ability to transmit the music will be impaired.
The puzzle of altruism can also be explained. If, as many scientists believe, human beings are just genetic machines, only concerned with the survival and propagation of our genes, then altruism is difficult to account for.
It makes sense for us to be altruistic to people who are closely related to us genetically, but not so much to strangers, or to members of different species. In the latter cases, from the conventional point of view, there must be some benefit to us, even if we’re not aware of it.
Perhaps being kind makes us feel good about ourselves, impresses other people, or encourages people to be kind to us in return.
But these explanations seem unable to explain the full range and depth of human altruism. If we are fundamentally selfish, why should we be willing to risk our own lives for the sake of others? Altruism is often instantaneous and spontaneous, particularly in crisis situations, as if it is deeply instinctive.
From a ‘spiritual’ perspective (which sees consciousness as fundamental), though, altruism is easy to explain. It is related to empathy.
Human shared fundamental consciousness means that it is possible for us to sense the suffering of others and to respond with altruistic acts. Since we share fundamental consciousness with other species, too, it is possible for us to feel empathy with — and to behave altruistically towards — them as well.
One of my main areas of interest as a psychologist is in what I call ‘awakening experiences,’ when human awareness intensifies and expands and we experience a sense of oneness with other human beings, nature or the world as a whole.
I see awakening experiences as encounters with fundamental consciousness, in which we sense its presence in everything around us, including our own selves. We experience a sense of oneness because oneness is the fundamental reality of things.
Conventional science also struggles to explain the powerful effect of mental intention and belief on the body (as illustrated by the placebo effect and the pain numbing effects of hypnosis). If the mind is just a byproduct of matter, it should not be able to influence the form and functioning of the body so profoundly.
That would be like saying that images on a computer screen can change the software or hardware inside the computer. But these effects are comprehensible if we presume that mind is more fundamental than the matter of the body, a more subtle and fuller expression of fundamental consciousness. As a result, it has the capacity to alter the functioning of the body.
I believe the idea of consciousness as a fundamental quality of the Universe has a great deal of weight. As I point out in my book Spiritual Science, it may be that the best way to understand the world is not through science or spirituality alone — but through an approach which combines them both.
Researchers have potentially identified a brain region where images are retained during our conscious perception, a significant step towards understanding consciousness.
This breakthrough study focuses on the phenomenon of unilateral neglect, where stroke victims lose conscious awareness of half of their perceived surroundings, despite being able to react emotionally to the full scene.
This discovery could shed light on the mystery of how we can perceive things without being consciously aware of them. The research could lead to better treatment strategies for consciousness disorders, and enhance our understanding of coma patients’ awareness levels.
Key Facts:
The study investigated the condition of unilateral neglect, where stroke victims lose conscious awareness of half of their visual field but still respond emotionally to the entire scene.
The researchers suggest that they may have located the brain region where images are held during the moments we consciously perceive them.
This research could significantly contribute to understanding consciousness and treating consciousness disorders, and might provide insight into the level of awareness in coma patients.
Source: UC Berkeley
More than a quarter of all stroke victims develop a bizarre disorder—they lose conscious awareness of half of all that their eyes perceive.
After a stroke in the brain’s right half, for example, a person might eat only what’s on the right side of the plate because they’re unaware of the other half. The person may see only the right half of a photo and ignore a person on their left side.
Credit: Neuroscience News
Surprisingly, though, such stroke victims can emotionally react to the entire photo or scene. Their brains seem to be taking it all in, but these people are consciously aware of only half the world.
This puzzling affliction, called unilateral neglect, highlights a longstanding question in brain science: What’s the difference between perceiving something and being aware or conscious of perceiving it? You may not consciously note that you passed a shoe store while scrolling through your Instagram feed, yet you started searching online for shoe sales. Your brain records things that you don’t consciously take note of.
Neuroscientists from the Hebrew University of Jerusalem and the University of California, Berkeley, now report that they may have found the region of the brain where these sustained visual images are retained during the few seconds we perceive them.
They published their findings this month in the journal Cell Reports.
“Consciousness, and in particular, visual experience, is the most fundamental thing that everyone feels from the moment they open their eyes when they wake up in the morning to the moment they go to sleep,” said Hebrew University graduate student Gal Vishne, lead author of the paper.
“Our study is about your everyday experience.”
While the findings do not yet explain how we can be unaware of what we perceive, studies like these could have practical applications in the future, perhaps allowing doctors to tell from a coma patient’s brain activity whether the person is still aware of the outside world and potentially able to improve. Understanding consciousness may also help doctors develop treatments for disorders of consciousness.
“The inspiration for my whole scientific career comes from patients with stroke who suffer from unilateral neglect, where they just ignore half of the world,” said senior author Leon Deouell, a Hebrew University professor of psychology and member of the Edmond and Lily Safra Center for brain research.
“That actually triggered my whole interest in the question of conscious awareness. How is it that you can have the information, but still not acknowledge it as something that you’re subjectively experiencing, not act upon it, not move your eyes to it, not grab it? What is required for something not only to be sensed by the brain, but for you to have a subjective experience?
“Understanding that would eventually help us understand what is missing in the cognitive system and in the brains of patients who have this kind of a syndrome.”
“We are adding a piece to the puzzle of consciousness—how things remain in your mind’s eye for you to act on,” added Robert Knight, also a senior author and a UC Berkeley professor of psychology and member of the Helen Wills Neuroscience Institute.
The brain has a transient and a sustained response
Deouell noted that for some six decades, electrical studies of the human brain have almost solely concentrated on the initial surge of activity after something is perceived. But this spike dies out after about 300 or 400 milliseconds, while we often look at and are consciously aware of things for seconds or longer.
“That leaves a whole lot of time which is not explained in neural terms,” he said.
In search of longer-lasting activity, the neuroscientists obtained consent to run tests on 10 people whose skulls were being opened so that electrodes could be placed on the brain surface to track neural activity associated with epileptic seizures.
The researchers recorded brain activity from the electrodes as they showed different images to the patients on a computer screen for different lengths of time, up to 1.5 seconds. The patients were asked to press a button when they saw an occasional item of clothing to ensure that they truly were paying attention.
Most methods used to record neural activity in humans, such as functional MRI (fMRI) or electroencephalography (EEG), only allow researchers to make detailed inferences about where brain activity is happening or when, but not both.
By employing electrodes implanted inside the skull, the Hebrew University/UC Berkeley researchers were able to bridge this gap.
After analyzing the data using machine learning, the team found that, contrary to earlier studies that saw only a brief burst of activity in the brain when something new was perceived, the visual areas of the brain actually retained information about the percept at a low level of activity for much longer.
The sustained pattern of neural activity was similar to the pattern of the initial activity and changed when a person viewed a different image.
“This stable representation suggests a neural basis for stable perception over time, despite the changing level of activity,” Deouell said.
Unlike some earlier studies, they found that the prefrontal and parietal cortexes in the front of the brain become active only when something new is perceived, with information disappearing entirely within half a second (500 milliseconds), even for a much longer stimulus.
The occipitotemporal area of the visual cortex in the back of the brain also becomes very active briefly—for about 300 milliseconds—and then drops to a sustained but low level, about 10% to 20% of the initial spike. But the pattern of activity does not go away; it actually lasts unaltered about as long as a person views an image.
“The frontal cortex is involved in the detection of something new,” Deouell explained. “But you also see an ongoing representation in the higher-level sensory regions.”
The sequence of events in the brain could be interpreted in various ways. Knight and Vishne lean toward the idea that conscious awareness comes when the prefrontal cortex accesses the sustained activity in the visual cortex.
Deouell suspects that consciousness arises from connections among many areas of the brain, the prefrontal cortex being just one of them.
The team’s findings have been confirmed by a group that calls itself the Cogitate Consortium. Though the consortium’s results are still awaiting peer review, they were described in a June event in New York City that was billed as a face-off between two “leading” theories of consciousness.
Both the Cell Reports results and the unpublished results could fit either theory of consciousness.
“That adversarial collaboration involves two theories out of something like 22 current theories of consciousness,” Deouell cautioned. “Many theories usually means that we don’t understand.”
Nevertheless, the two studies and other ongoing studies that are part of the adversarial collaboration initiated by the Templeton Foundation could lead to a true, testable theory of consciousness.
“Regarding the predictions of the two theories which we were able to test, both are correct. But looking at the broader picture, none of the theories in their current form work, even though we find each to have some grain of truth, at the moment,” Vishne said.
“With so much still unknown about the neural basis of consciousness, we believe that more data should be collected before a new phoenix can rise out of the ashes of the previous theories. “
Future studies planned by Deouell and Knight will explore the electrical activity associated with consciousness in other regions of the brain, such as the areas that deal with memory and emotions.
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