Unconsciousness

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Unconsciousness
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An unconscious male human laying in a recovery position
Specialty Psychiatry
Neurology
Cardiology
Pulmonology

Unconsciousness is a state in which a living individual exhibits a complete, or near-complete, inability to maintain an awareness of self and environment or to respond to any human or environmental stimulus. [1] Unconsciousness may occur as the result of traumatic brain injury, brain hypoxia (inadequate oxygen, possibly due to a brain infarction or cardiac arrest), severe intoxication with drugs that depress the activity of the central nervous system (e.g., alcohol and other hypnotic or sedative drugs), severe fatigue, pain, anaesthesia, and other causes.

Contents

Loss of consciousness should not be confused with the notion of the psychoanalytic unconscious, cognitive processes that take place outside awareness (e.g., implicit cognition), and with altered states of consciousness such as sleep, delirium, hypnosis, and other altered states in which the person responds to stimuli, including trance and psychedelic experiences.

Law and medicine

Person passed out on a sidewalk in New York City, 2008 Person passed out on sidewalk photographed with a dutch angle NYC.tif
Person passed out on a sidewalk in New York City, 2008

In jurisprudence, unconsciousness may entitle the criminal defendant to the defense of automatism, i.e. a state without control of one's own actions, an excusing condition that allows a defendant to argue that they should not be held criminally liable for their actions or omissions. In most countries, courts must consider whether unconsciousness in a situation can be accepted as a defense; it can vary from case to case. Hence epileptic seizures, neurological dysfunctions and sleepwalking may be considered acceptable excusing conditions because the loss of control is not foreseeable, but falling asleep (especially while driving or during any other safety-critical activity) may not, because natural sleep rarely overcomes an ordinary person without warning.

In many countries, it is presumed that someone who is less than fully conscious cannot give consent to anything. This can be relevant in cases of sexual assault, euthanasia, or patients giving informed consent with regard to starting or stopping a medical treatment.

See also

Related Research Articles

<span class="mw-page-title-main">Coma</span> State of unconsciousness

A coma is a deep state of prolonged unconsciousness in which a person cannot be awakened, fails to respond normally to painful stimuli, light, or sound, lacks a normal wake-sleep cycle and does not initiate voluntary actions. The person may experience respiratory and circulatory problems due to the body's inability to maintain normal bodily functions. People in a coma often require extensive medical care to maintain their health and prevent complications such as pneumonia or blood clots. Coma patients exhibit a complete absence of wakefulness and are unable to consciously feel, speak or move. Comas can be derived by natural causes, or can be medically induced.

<span class="mw-page-title-main">Hypnosis</span> State of increased receptivity to suggestion and direction

Hypnosis is a human condition involving focused attention, reduced peripheral awareness, and an enhanced capacity to respond to suggestion.

In criminal law, Actus reus, Latin for "guilty act", is one of the elements normally required to prove commission of a crime in common law jurisdictions, the other being mens rea. In the United States it is sometimes called the external element or the objective element of a crime.

In American jurisprudence, an excuse is a defense to criminal charges that is distinct from an exculpation. Justification and excuse are different defenses in a criminal case. Exculpation is a related concept which reduces or extinguishes a person's culpability, such as their liability to pay compensation to the victim of a tort in the civil law.

An altered state of consciousness (ASC), also called altered state of mind or mind alteration, is any condition which is significantly different from a normal waking state. By 1892, the expression was in use in relation to hypnosis, though there is an ongoing debate as to whether hypnosis is to be identified as an ASC according to its modern definition. The next retrievable instance, by Max Mailhouse from his 1904 presentation to conference, however, is unequivocally identified as such, as it was in relation to epilepsy, and is still used today. In academia, the expression was used as early as 1966 by Arnold M. Ludwig and brought into common usage from 1969 by Charles Tart. It describes induced changes in one's mental state, almost always temporary. A synonymous phrase is "altered state of awareness".

A vegetative state (VS) or post-coma unresponsiveness (PCU), is a disorder of consciousness in which patients with severe brain damage are in a state of partial arousal rather than true awareness. After four weeks in a vegetative state, the patient is classified as being in a persistent vegetative state (PVS). This diagnosis is classified as a permanent vegetative state some months after a non-traumatic brain injury or one year after a traumatic injury. The term unresponsive wakefulness syndrome may be alternatively used, as "vegetative state" has some negative connotations among the public.

<span class="mw-page-title-main">Concussion</span> Type of traumatic brain injury

A concussion, also known as a mild traumatic brain injury (mTBI), is a head injury that temporarily affects brain functioning. Symptoms may include loss of consciousness; memory loss; headaches; difficulty with thinking, concentration, or balance; nausea; blurred vision; dizziness; sleep disturbances, and mood changes. Any of these symptoms may begin immediately, or appear days after the injury. Concussion should be suspected if a person indirectly or directly hits their head and experiences any of the symptoms of concussion. Symptoms of a concussion may be delayed by 1–2 days after the accident. It is not unusual for symptoms to last 2 weeks in adults and 4 weeks in children. Fewer than 10% of sports-related concussions among children are associated with loss of consciousness.

Dissociation is a concept that has been developed over time and which concerns a wide array of experiences, ranging from a mild emotional detachment from the immediate surroundings, to a more severe disconnection from physical and emotional experiences. The major characteristic of all dissociative phenomena involves a detachment from reality, rather than a loss of reality as in psychosis.

<span class="mw-page-title-main">Minimally conscious state</span> Disorder of Consciousness where overt signs of awareness are preserved

A minimally conscious state or MCS is a disorder of consciousness distinct from persistent vegetative state and locked-in syndrome. Unlike persistent vegetative state, patients with MCS have partial preservation of conscious awareness. MCS is a relatively new category of disorders of consciousness. The natural history and longer term outcome of MCS have not yet been thoroughly studied. The prevalence of MCS was estimated to be 9 times of PVS cases, or between 112,000 and 280,000 in the US by year 2000.

In criminal law, automatism is a rarely used criminal defence. It is one of the mental condition defences that relate to the mental state of the defendant. Automatism can be seen variously as lack of voluntariness, lack of culpability (unconsciousness) or excuse. Automatism means that the defendant was not aware of his or her actions when making the particular movements that constituted the illegal act.

In criminal law, consent may be used as an excuse and prevent the defendant from incurring liability for what was done.

Post-traumatic amnesia (PTA) is a state of confusion that occurs immediately following a traumatic brain injury (TBI) in which the injured person is disoriented and unable to remember events that occur after the injury. The person may be unable to state their name, where they are, and what time it is. When continuous memory returns, PTA is considered to have resolved. While PTA lasts, new events cannot be stored in the memory. About a third of patients with mild head injury are reported to have "islands of memory", in which the patient can recall only some events. During PTA, the patient's consciousness is "clouded". Because PTA involves confusion in addition to the memory loss typical of amnesia, the term "post-traumatic confusional state" has been proposed as an alternative.

In the field of criminal law, there are a variety of conditions that will tend to negate elements of a crime, known as defenses. The label may be apt in jurisdictions where the accused may be assigned some burden before a tribunal. However, in many jurisdictions, the entire burden to prove a crime is on the prosecution, which also must prove the absence of these defenses, where implicated. In other words, in many jurisdictions the absence of these so-called defenses is treated as an element of the crime. So-called defenses may provide partial or total refuge from punishment.

<span class="mw-page-title-main">Neural correlates of consciousness</span> Neuronal events sufficient for a specific conscious percept

The neural correlates of consciousness (NCC) refer to the relationships between mental states and neural states and constitute the minimal set of neuronal events and mechanisms sufficient for a specific conscious percept. Neuroscientists use empirical approaches to discover neural correlates of subjective phenomena; that is, neural changes which necessarily and regularly correlate with a specific experience. The set should be minimal because, under the materialist assumption that the brain is sufficient to give rise to any given conscious experience, the question is which of its components are necessary to produce it.

Traumatic brain injury can cause a variety of complications, health effects that are not TBI themselves but that result from it. The risk of complications increases with the severity of the trauma; however even mild traumatic brain injury can result in disabilities that interfere with social interactions, employment, and everyday living. TBI can cause a variety of problems including physical, cognitive, emotional, and behavioral complications.

<span class="mw-page-title-main">Altered level of consciousness</span> Measure of arousal other than normal

An altered level of consciousness is any measure of arousal other than normal. Level of consciousness (LOC) is a measurement of a person's arousability and responsiveness to stimuli from the environment. A mildly depressed level of consciousness or alertness may be classed as lethargy; someone in this state can be aroused with little difficulty. People who are obtunded have a more depressed level of consciousness and cannot be fully aroused. Those who are not able to be aroused from a sleep-like state are said to be stuporous. Coma is the inability to make any purposeful response. Scales such as the Glasgow coma scale have been designed to measure the level of consciousness.

<span class="mw-page-title-main">Trance</span> Abnormal state of wakefulness or altered state of consciousness

Trance is a state of semi-consciousness in which a person is not self-aware and is either altogether unresponsive to external stimuli or is selectively responsive in following the directions of the person who has induced the trance. Trance states may occur involuntarily and unbidden.

<span class="mw-page-title-main">Criminal law of the United States</span>

Criminal law is a system of laws that is connected with crimes and punishments of an individual who commits crimes. In comparison, civil law is where the case argues their issues with one entity to another entity with support of the law. Crimes can vary in definition by jurisdiction but the basis for a crime are fairly consistent regardless.

Disorders of consciousness are medical conditions that inhibit consciousness. Some define disorders of consciousness as any change from complete self-awareness to inhibited or absent self-awareness and arousal. This category generally includes minimally conscious state and persistent vegetative state, but sometimes also includes the less severe locked-in syndrome and more severe but rare chronic coma. Differential diagnosis of these disorders is an active area of biomedical research. Finally, brain death results in an irreversible disruption of consciousness. While other conditions may cause a moderate deterioration or transient interruption of consciousness, they are not included in this category.

Unconscious fraud is fraud committed by somebody who does not consciously realise that they are deceiving others. Examples could be a hypnotised person or perhaps a medium in a trance, neither of whom would consciously realise that they are engaging in acts which make others believe – such as that a 'spirit' has moved an object.

References

  1. "MeSH Browser". www.nlm.nih.gov. Retrieved 18 March 2018.