The Nature of Consciousness: For example, assuming that birds are conscious — a common assumption among neuroscientists and ethologists due to the extensive cognitive repertoire of birds — there are comparative neuroanatomical ways to validate some of the principal, currently competing, mammalian consciousness—brain theories. A conscience is a built-in sense of what's right and what's wrong. Nearby words for conscious conscient conscientious conscientious objection conscientious objector conscionable conscious.
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The two most widely accepted altered states are sleep and dreaming. Although dream sleep and non-dream sleep appear very similar to an outside observer, each is associated with a distinct pattern of brain activity, metabolic activity, and eye movement; each is also associated with a distinct pattern of experience and cognition.
During ordinary non-dream sleep, people who are awakened report only vague and sketchy thoughts, and their experiences do not cohere into a continuous narrative. During dream sleep, in contrast, people who are awakened report rich and detailed experiences in which events form a continuous progression, which may however be interrupted by bizarre or fantastic intrusions.
Both dream and non-dream states are associated with severe disruption of memory: Research conducted on the effects of partial epileptic seizures on consciousness found that patients who suffer from partial epileptic seizures experience altered states of consciousness. Studies found that when measuring the qualitative features during partial epileptic seizures, patients exhibited an increase in arousal and became absorbed in the experience of the seizure, followed by difficulty in focusing and shifting attention.
A variety of psychoactive drugs , including alcohol , have notable effects on consciousness. The brain mechanisms underlying these effects are not as well understood as those induced by use of alcohol ,  but there is substantial evidence that alterations in the brain system that uses the chemical neurotransmitter serotonin play an essential role. There has been some research into physiological changes in yogis and people who practise various techniques of meditation.
Some research with brain waves during meditation has reported differences between those corresponding to ordinary relaxation and those corresponding to meditation. It has been disputed, however, whether there is enough evidence to count these as physiologically distinct states of consciousness.
The most extensive study of the characteristics of altered states of consciousness was made by psychologist Charles Tart in the s and s. Tart analyzed a state of consciousness as made up of a number of component processes, including exteroception sensing the external world ; interoception sensing the body ; input-processing seeing meaning ; emotions; memory; time sense; sense of identity; evaluation and cognitive processing; motor output; and interaction with the environment.
The components that Tart identified have not, however, been validated by empirical studies. Research in this area has not yet reached firm conclusions, but a recent questionnaire-based study identified eleven significant factors contributing to drug-induced states of consciousness: Phenomenology is a method of inquiry that attempts to examine the structure of consciousness in its own right, putting aside problems regarding the relationship of consciousness to the physical world.
This approach was first proposed by the philosopher Edmund Husserl , and later elaborated by other philosophers and scientists. In philosophy , phenomenology has largely been devoted to fundamental metaphysical questions, such as the nature of intentionality "aboutness". In psychology , phenomenology largely has meant attempting to investigate consciousness using the method of introspection , which means looking into one's own mind and reporting what one observes.
This method fell into disrepute in the early twentieth century because of grave doubts about its reliability, but has been rehabilitated to some degree, especially when used in combination with techniques for examining brain activity.
Introspectively, the world of conscious experience seems to have considerable structure. Immanuel Kant asserted that the world as we perceive it is organized according to a set of fundamental "intuitions", which include 'object' we perceive the world as a set of distinct things ; 'shape'; 'quality' color, warmth, etc.
Understanding the physical basis of qualities, such as redness or pain, has been particularly challenging. David Chalmers has called this the hard problem of consciousness. For example, research on ideasthesia shows that qualia are organised into a semantic-like network.
Nevertheless, it is clear that the relationship between a physical entity such as light and a perceptual quality such as color is extraordinarily complex and indirect, as demonstrated by a variety of optical illusions such as neon color spreading. In neuroscience, a great deal of effort has gone into investigating how the perceived world of conscious awareness is constructed inside the brain.
The process is generally thought to involve two primary mechanisms: Signals arising from sensory organs are transmitted to the brain and then processed in a series of stages, which extract multiple types of information from the raw input. In the visual system, for example, sensory signals from the eyes are transmitted to the thalamus and then to the primary visual cortex ; inside the cerebral cortex they are sent to areas that extract features such as three-dimensional structure, shape, color, and motion.
First, it allows sensory information to be evaluated in the context of previous experience. Second, and even more importantly, working memory allows information to be integrated over time so that it can generate a stable representation of the world— Gerald Edelman expressed this point vividly by titling one of his books about consciousness The Remembered Present.
Bayesian models of the brain are probabilistic inference models, in which the brain takes advantage of prior knowledge to interpret uncertain sensory inputs in order to formulate a conscious percept; Bayesian models have successfully predicted many perceptual phenomena in vision and the nonvisual senses. Despite the large amount of information available, many important aspects of perception remain mysterious.
A great deal is known about low-level signal processing in sensory systems. However, how sensory systems, action systems, and language systems interact are poorly understood. At a deeper level, there are still basic conceptual issues that remain unresolved. Gibson and roboticist Rodney Brooks , who both argued in favor of "intelligence without representation".
The medical approach to consciousness is practically oriented. It derives from a need to treat people whose brain function has been impaired as a result of disease, brain damage, toxins, or drugs. In medicine, conceptual distinctions are considered useful to the degree that they can help to guide treatments.
Whereas the philosophical approach to consciousness focuses on its fundamental nature and its contents, the medical approach focuses on the amount of consciousness a person has: Consciousness is of concern to patients and physicians, especially neurologists and anesthesiologists. Patients may suffer from disorders of consciousness, or may need to be anesthetized for a surgical procedure.
Physicians may perform consciousness-related interventions such as instructing the patient to sleep, administering general anesthesia , or inducing medical coma. In medicine, consciousness is examined using a set of procedures known as neuropsychological assessment.
The simple procedure begins by asking whether the patient is able to move and react to physical stimuli. If so, the next question is whether the patient can respond in a meaningful way to questions and commands. If so, the patient is asked for name, current location, and current day and time. The more complex procedure is known as a neurological examination , and is usually carried out by a neurologist in a hospital setting.
A formal neurological examination runs through a precisely delineated series of tests, beginning with tests for basic sensorimotor reflexes, and culminating with tests for sophisticated use of language. The outcome may be summarized using the Glasgow Coma Scale , which yields a number in the range 3—15, with a score of 3 to 8 indicating coma, and 15 indicating full consciousness.
The Glasgow Coma Scale has three subscales, measuring the best motor response ranging from "no motor response" to "obeys commands" , the best eye response ranging from "no eye opening" to "eyes opening spontaneously" and the best verbal response ranging from "no verbal response" to "fully oriented". There is also a simpler pediatric version of the scale, for children too young to be able to use language.
In , an experimental procedure was developed to measure degrees of consciousness, the procedure involving stimulating the brain with a magnetic pulse, measuring resulting waves of electrical activity, and developing a consciousness score based on the complexity of the brain activity. Medical conditions that inhibit consciousness are considered disorders of consciousness. One of the most striking disorders of consciousness goes by the name anosognosia , a Greek-derived term meaning 'unawareness of disease'.
This is a condition in which patients are disabled in some way, most commonly as a result of a stroke , but either misunderstand the nature of the problem or deny that there is anything wrong with them. Patients with hemispatial neglect are often paralyzed on the right side of the body, but sometimes deny being unable to move.
When questioned about the obvious problem, the patient may avoid giving a direct answer, or may give an explanation that doesn't make sense. Patients with hemispatial neglect may also fail to recognize paralyzed parts of their bodies: An even more striking type of anosognosia is Anton—Babinski syndrome , a rarely occurring condition in which patients become blind but claim to be able to see normally, and persist in this claim in spite of all evidence to the contrary.
William James is usually credited with popularizing the idea that human consciousness flows like a stream, in his Principles of Psychology of According to James, the "stream of thought" is governed by five characteristics: Buddhist teachings describe that consciousness manifests moment to moment as sense impressions and mental phenomena that are continuously changing.
The mental events generated as a result of these triggers are: The moment-by-moment manifestation of the mind-stream is said to happen in every person all the time. It even happens in a scientist who analyses various phenomena in the world, or analyses the material body including the organ brain. In the west, the primary impact of the idea has been on literature rather than science: This technique perhaps had its beginnings in the monologues of Shakespeare's plays, and reached its fullest development in the novels of James Joyce and Virginia Woolf , although it has also been used by many other noted writers.
Here for example is a passage from Joyce's Ulysses about the thoughts of Molly Bloom:. Consciousness may have a determinative role in quantum mechanics. Since consciousness is the primary aspect of an observer, and observation is sometimes viewed as a primary reason for apparent wave function collapse ,  consciousness may account for aspects of the measurement problem exemplified by the Schrödinger's cat paradox. This area has been an area of lively debate for decades,  with recent efforts to substitute randomly caused decoherence as the source of apparent wave function collapse.
Max Tegmark and John Archibald Wheeler provided a useful survey  of some of the issues. To most philosophers, the word "consciousness" connotes the relationship between the mind and the world.
To writers on spiritual or religious topics, it frequently connotes the relationship between the mind and God, or the relationship between the mind and deeper truths that are thought to be more fundamental than the physical world.
Krishna consciousness , for example, is a term used to mean an intimate linkage between the mind of a worshipper and the god Krishna. Wilber described consciousness as a spectrum with ordinary awareness at one end, and more profound types of awareness at higher levels.
From Wikipedia, the free encyclopedia. This article is about cognition. For other uses, see Consciousness disambiguation and Conscious disambiguation.
Problem of other minds. Schema of the neural processes underlying consciousness, from Christof Koch. Stream of consciousness psychology. Level of consciousness esotericism and Higher consciousness. Consciousness portal Medicine portal Mind and Brain portal Philosophy portal. Retrieved June 4, Stanford Encyclopedia of Philosophy. The Psychology of Consciousness. The Oxford companion to philosophy. In Max Velmans, Susan Schneider. The Blackwell Companion to Consciousness. Uses authors parameter link CS1 maint: Man, cultures, and groups in a quantum perspective.
Charles University Karolinum Press. The Nature of Consciousness: Retrieved August 20, A Dictionary of the English Language. Translated by Scott St. Michigan Publishing, University of Michigan Library, Originally published as "Conscience," Encyclopédie ou Dictionnaire raisonné des sciences, des arts et des métiers, 3: The whole works, Volume 2.
British Journal for the History of Philosophy. Routledge Encyclopedia of Philosophy. Macmillan Dictionary of Psychology. Journal of Consciousness Studies. The Concept of Mind. University of Chicago Press. Archived from the original on Behavioral and Brain Sciences.
Stanford Encyclopedia of Philosophy Summer Edition. John Wiley and Sons. Machine man and other writings. Bright Air, Brilliant Fire: On the Matter of the Mind. The Feeling of What Happens: Body and Emotion in the Making of Consciousness. The Quest for Consciousness. A taxonomy and some examples.
Cambridge University Press, New York. How bio-molecular machines can generate non-trivial quantum states". The Mystery of Consciousness. The New York Review of Books. Consciousness, Concepts, and Higher-Order Thoughts. Australasian Journal of Philosophy. In Douglas Hofstadter and Daniel Dennett.
Beyond Cognition to Consciousness. Uses authors parameter link Note: In many stories the Golem was mindless, but some gave it emotions or thoughts. Verbal Behavior as the Hallmark of Intelligence. In Search of a Fundamental Theory. Stanford Encyclopedia of Philosophy Spring Edition. The Phenomenal Judgment Approach". Journal of Mind and Behavior. Catching ourselves in the act: These are fairly formal expressions.
Conscience is a noun. Your conscience is the part of your mind that tells you whether what you are doing is right or wrong. Conscientious is an adjective. Someone who is conscientious is very careful to do their work properly. Conscious - definition of conscious by The Free Dictionary https: Characterized by or having an awareness of one's environment and one's own existence, sensations, and thoughts.
See Synonyms at aware. Mentally perceptive or alert; awake: The patient remained fully conscious after the local anesthetic was administered.
Capable of thought, will, or perception: Subjectively known or felt: Intentionally conceived or done; deliberate: Inwardly attentive or sensitive to something: As he spoke, he became increasingly conscious of his high-pitched voice.
First Known Use of conscious Adjective circa , in the meaning defined at sense 2 Noun , in the meaning defined above. Learn More about conscious.
Resources for conscious Time Traveler! Explore the year a word first appeared. Dictionary Entries near conscious conscientious objection conscientious objector conscionable conscious consciousness consciousness-raising conscribe. Time Traveler for conscious The first known use of conscious was circa See more words from the same year. More Definitions for conscious. English Language Learners Definition of conscious. Kids Definition of conscious.
Other Words from conscious consciously adverb. More from Merriam-Webster on conscious Thesaurus: All synonyms and antonyms for conscious Spanish Central: Translation of conscious Nglish: Translation of conscious for Spanish Speakers Britannica English: Comments on conscious What made you want to look up conscious? Get Word of the Day daily email! Need even more definitions?
Conscious, aware, cognizant refer to an individual sense of recognition of something within or without oneself. Conscious implies to be awake or awakened to an inner realization of a fact, a truth, a condition, etc.: to be conscious of an extreme weariness. Conscious definition is - having mental faculties not dulled by sleep, faintness, or stupor: awake. How to use conscious in a sentence. Synonym Discussion of conscious. having mental faculties not dulled by sleep, faintness, or stupor: awake See the full definition. SINCE Consciousness is the state or quality of awareness or of being aware of an external object or something within oneself. It has been defined variously in terms of sentience, The earliest English language uses of "conscious" and "consciousness" date back, however, to the s.