Definitions of Consciousness
The primary actions that keep us alive, such as breathing, seeing, hearing, touching and even tasting, take place without our conscious participation or stopping to think about them. Even most of our automatic, purposeful behavior such as solving most of our routine problems happens without the aid of our full consciousness. Life without consciousness is simple in most respects. We are merely living our lives without concentrated thoughtful efforts.
But, when a purpose or result can be achieved by alternative means, we call upon consciousness. In other words, at the routine level of existence, we do not employ consciousness except when we are altering our actions or thoughts from the routine, for a purpose. (Bharati Sarkar, Global Oneness) Depending upon conscious recall, we push our attention-demanding mechanisms.
Consciousness can be defined as "subjective experience or awareness or wakefulness or the executive control system of the mind. (Farthing, 1992) As we can see, it is an umbrella term that may refer to a variety of mental phenomena. Humans can realize what everyday experiences are, yet consciousness refuses to be simply defined by philosophy or science. Since conscious experiences are constantly shifting and changing, consciousness refers to an awareness of unique thoughts, memories, feelings, sensations, and environment.
Different Consciousness Levels In Different Life Forms"Anything that we are aware of at a given moment forms part of our consciousness, making conscious experience at once the most familiar and most mysterious aspect of our lives"
—Schneider and Velmans, 2007
Most of us generally agree that our fellow human beings are conscious, and that much simpler life forms, such as bacteria or snails are not "conscious" as we know it. Consciousness, many believe, requires a nervous system sufficiently evolved and complex that the organism can hold in mind the image of a protoself moving through and interacting with the world.
Animals such as dogs may have what Dr. Antonio Damasion (J. Madeleine Nash, Time, October 18 1999) calls "core" consciousness that registers "the feeling of what happens." This increased degree of recall allows these animals to learn certain limited behaviors as they relate to a stimulus, unlike the bacteria or snail.
Many of us attribute true consciousness to higher-order animals such as great apes and humans, and current academic research is investigating the extent to which other high-order animals (dolphins, for example) are conscious in this manner. This highest form of consciousness "embellishes one's image of self with a wealth of autobiographical detail."
Damasio calls this "extended consciousness," and it requires a vast capacity for memory. Hence, he believes damage to the human brain's memory centers can impair a person's extended consciousness while leaving the core consciousness intact.This suggests the hypothesis that consciousness has co-evolved with life, which would require it to have some sort of added value, especially great survival value.
According to Timothy E. Moore PhD (Gale Encyclopedia of Nursing and Allied Health, 2002), "A state of consciousness allows us to exert purposeful control over our current activities, and to communicate our mental states to others. We selectively attend to only a small fraction of the stimulation to which we are constantly exposed." We ignore many sources of external information, but can be made instantly aware of them.
The Salk Institute has suggested (Crick and Koch, 1995) that the biological usefulness of visual consciousness in humans is to produce the best current interpretation of the visual scene in the light of past experience, either of ourselves or of our ancestors (embodied in our genes), and to make this interpretation directly available, for a sufficient time, to the parts of the brain that contemplate and plan voluntary motor output, of one sort or another, including speech.
What Happens When Consciousness Occurs?
But, how does consciousness arise? How do we get this living, aware experience of being? Some theories hold that consciousness comes from, or is even identical to, electrical and chemical processes known to unfold in the brain.
"Others claim it arises elsewhere: in some subtler, yet-undiscovered brain processes, or perhaps a mind-stuff quite distinct from the brain -- some call it a soul." (World Science, May 20 2007)
Damasio doesn't regard any one region of the brain--or the brain as a whole--as the seat of consciousness. He understands the brain as an interconnected system with cognition (language, memory, reason and emotion) and sensory processes (vision, hearing, touch and taste) centered in different areas. "Consciousness," he says, "is similarly dispersed." (J. Madeleine Nash, Time, October 18 1999)
Damasio doesn't regard language as the wellspring of consciousness, as some have claimed it is. Much closer to the wellspring, he says, are our emotions. Indeed, to him, consciousness "is the feeling of knowing that we have feelings." (J. Madeleine Nash, Time, October 18 1999)
One philosopher, Derek Parfit, starkly reports, "We are not what we believe ourselves to be. Actions and experiences are interconnected but ownerless. A human life consists of a long series - or bundle - of enmeshed mental states rolling like tumbleweed down the days and years, but with no one (no thing) at the centre. An embodied brain acts, thinks, has certain experiences, and that's all. There is no deeper fact about being a person. The enchanted loom of the brain does not require a weaver (operator of conscious machinery)." (Paul Broks, www.newscientist.com, Issue 2578, November 18 2006)
Levels of Human Consciousness
Thanks to Timothy E. Moore, PhD
Greenwald, A. W. "New look 3: Unconscious cognition reclaimed." American Psychologist 47 (1992): 766-779.
Moore, T. E. "Subliminal perception: facts and fallacies."
Merikle, P. M., & Joordens, S. "Measuring Unconscious Influences." In Scientific Approaches to Consciousness. Ed. by J. D. Cohen & J. W. Schooler. Mahwah NJ: Erlbaum,1997.
1. Sleep
There are four major stages of sleep that are distinguished from one another on the basis of the electrical activity associated with each. There is also a distinctive fifth stage, known as REM (rapid eye movement) sleep. During this phase the brain's electrical activity is similar to that of the waking state. REM sleep is called "paradoxical sleep." There is considerable internal activity, but an external calmness. Regardless of the stage of sleep, there is no evidence that any substantive learning can take place during sleep.
2. Hypothesis
How dependable is hypnosis or trance consciousness? Hypnotically revived memories often combine fact with fiction. Under hypnosis, people are more likely to use their imagination to construct or retrieve their recollections. Consequently, there is a danger that people will confidently assert having a memory of something they never experienced. Whether giving into a hypnotist's irresistible suggestions or falsely complying, numerous studies have shown that normal subjects who are asked to pretend to be hypnotized produce behaviors that are indistinguishable from those of hypnotized subjects.
3. Automatic and Controlled Processing
"Automatic processing" requires relatively little conscious awareness and makes little demand on limited attentional capacity. When a person drives a car while mentally reviewing the previous days' events, he is demonstrating automatic processing. Automatic processing develops with practice as the component parts of the activity become well learned.
"Controlled processing" refers to behaviors that require effort and deliberate concentration. It requires substantial use of cognitive resources. Consequently, tasks requiring controlled processing can usually only be performed one at a time. Automatic processing is rapid and effortless, but somewhat inflexible. Controlled processing is slower due to the effort required, but adaptable.
Think about the current argument of talking on a cell phone while driving. Can a person manage to execute two activities at the same time? What is one is "automatic" and one is "controlled"? Yes? But driving is not always "automatic." What about when a driver's reaction when the unexpected happens or what about a driver who is very animated in conversation?
4. Subliminal Perception
To what extent can we be influenced by stimuli whose presence we are not even aware of? There are numerous laboratory studies that show that individual words can be processed, even when presented so quickly that the viewer has no awareness of the word's identity. Can an advertiser induce a consumer to buy a product by presenting images or directives outside of conscious awareness? There is no evidence to suggest that people initiate actions on the basis of subliminally presented stimuli.
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