Altered state of consciousness
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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 beta wave state. By 1892, the expression was in use in relation to hypnosis but likely does not accord to the modern definition of ASC (see Concept). The next retrievable instance, by Dr Max Mailhouse from his 1904 presentation to conference, does however, as it was in relation to epilepsy, and is still used today (see Epilepsy). 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".
- 1 Definitions
- 2 Concept
- 3 Causes
- 4 Accidental and pathological causes
- 5 Intentional causes
- 6 Classification
- 7 See also
- 8 Notes
- 9 References
- 10 Sources
- 11 Further reading
Definition of Altered states of consciousness by Farthing:
Farthing’s definition of an Altered State of Consciousness (ASC) is based on Charles Tart’s terminology. Charles Tart described an altered state of consciousness as a profound change in the "overall pattern of subjective experiences”. In order to define an ASC Tart focuses on the importance of subjective experience.
Farthing adds to his definition that an ASC is short-termed or at least reversible and that it might not even be recognized as an ASC at that moment. His definition relies only on subjective experience, leaving aside behavioural changes and physiological response.
“An altered state of consciousness (ASC) may be defined as a temporary change in the overall pattern of subjective experience, such that the individual believes that his or her mental functioning is distinctly different from certain general norms for his or her normal waking state of consciousness”.— Farthing (1992, p. 205)
He lists fourteen dimensions of changed subjective experience. To account for an ASC multiple dimensions need to be altered. 
 The psychology of consciousness. G. William Farthing. Englewood Cliffs, New Jersey: Prentice-Hall, Inc., 1992. Chapter 9, p. 202
 The psychology of consciousness. G. William Farthing. Englewood Cliffs, New Jersey: Prentice-Hall, Inc., 1992 Chapter 9, p. 207-212
An altered state of consciousness is any mental state induced by physiological, psychological, or pharmacological maneuvers or agents, which deviates from the normal waking state of consciousness.
Revonsuo, Kallio, & Sikka (2009) arrived at three definitions,
What seems to be in common with these definitions is that there has to be a change in the content of consciousness (change in primary phenomenal consciousness) and at least an implicit assumption that the person being in an ASC should somehow recognize this and be able to give introspective reports about it (involvement of reflective consciousness) […] Thus, we arrive at three potential definitions of an ASC:
Definition 1.1: ASC as a state in primary phenomenal consciousness. ASC is defined by the changed (overall) pattern of subjective experience in primary phenomenal consciousness.
Definition 1.2: ASC is a phenomenal state in primary phenomenal consciousness and the corresponding cognitive state in reflective consciousness. ASC is defined by the changed (overall) pattern of subjective experience in primary phenomenal consciousness, coupled with the cognitive recognition of the change at the level of reflective consciousness, and classification of the experience as altered.
Definition 1.3: ASC is a psychological state and a neural state. ASC is defined as above in 1 or 2, but in addition to that, a corresponding altered pattern of neural activity must be involved and objectively detected.
Some observable abnormal and sluggish behaviors meet the criteria for altered state of consciousness. Altered states of consciousness can also be associated with artistic creativity or different focus levels. They also can be shared interpersonally and studied as a subject of sociological research.
Altered states of consciousness may be caused either accidentally or intentionally:
- Accidental and Pathological
Sometimes two or more causes lead to altered state of consciousness, for example a psychiatric disorder and consumption of psycho-active substances.
Altered states of consciousness can be assessed by observations and imaging of the brain such as computed tomography scan (CT), magnetic resonance imaging (MRI), or electroencephalography (EEG) which records the electrical brain wave activity. Imaging is most important to make a diagnosis when patient’s history is unobtainable and the physical examination is not dependable. (Dandan, 2004)
Accidental and pathological causes
Accidental and pathological causes refer to unforeseen events, or illnesses. According to Dr. Jeffrey R. Avner, professor of clinical pediatrics, a crucial element to understanding accidental and pathological causes to altered states of consciousness (ASC) is that it begins with reduced self-awareness followed by reduced awareness in the environment (2006). When the reduction of self-awareness and environmental awareness take effect, they produce altered states of consciousness. The specific conditions below provide clarity on the types of conditions compromise accidental and pathological causes.
The first condition, traumatic experience, is defined as a lesion caused by an external force (Trauma. (n.d.) In Merriam Webster Dictionary online, 2013). Examples include impact to the brain caused by blunt force (i.e., a car accident). The reason a traumatic experience causes altered states of consciousness is because it changes how the brain works. The external impact diverts the blood flow from the front of the brain to other areas. The front of the brain is known as the prefrontal cortex responsible for analytical thought (Kunsman, 2012). When the damage becomes uncontrollable, the patient experiences changes in behavior and impaired self-awareness. This is exactly when an ASC is experienced (Spikman et al. 2013).
Another common cause is epilepsy, according to Medlineplus epilepsy can be described as a brain disorder that causes seizures (2013). During the seizure it is said that the patient will experience hallucinations and loss of mental control (Revonsuo, Chaplin, and Wedlund, 2008) causing temporary dissociation from reality. A study that was conducted with six epileptic patients and used the functional magnetic resonance imaging (fMRI) detected how the patients did indeed experience hallucinations while a seizure is occurring (Korsnes M, Hugdahl K, Nygard M, Bjornæs H, 2010). This not only altered the patient’s behavioral pattern, but also made them dissociate from reality during that particular time frame.
The next item of interest is oxygen deficiency, questioning how oxygen deficiency impacts the brain is an important part of comprehending why ASC occurs when there is oxygen deprivation in an environment. A study conducted by Edwards, Harris, and Berisher illustrated how 20 navy men were impacted when they were exposed to nitrous oxide for 10 minutes. The study confirmed that inhaling substances other than oxygen results in impaired self-awareness, which can produce ASC (1976).
In addition to oxygen deprivation or deficiency, infections are a common pathological cause of ASC. A prime example of an infection includes meningitis. The medical website WEBMD  states that meningitis is an infection that causes the coverings of the brain to swell. This particular infection occurs in children and young adults. This infection is primarily viral. Viral meningitis causes ASC and its symptoms include fevers and seizures (2010). The Impairment becomes visible the moment seizures begin to occur, this is when the patient enters the altered state of consciousness.
Another type of deprivation that can cause ASC includes sleep deprivation. This refers to the loss of sleep that will provoke possible seizures, caused by fatigue. Sleep deprivation can be chronic or short-term depending on the severity of the patient’s condition. Many patients can even report hallucinations, because sleep deprivation impacts the brain as well. A Harvard Medical school study conducted in 2007, also indicated with the use of MRI (magnetic resonance imaging) that a sleep-deprived brain was not capable of being in control of its sensorimotor functions. Therefore, there was impairment to the patient’s self-awareness. Patients were also prone to be a lot clumsier than if had they not been experiencing sleep deprivation.
Coupled with deprivation of sleep and oxygen, another form of deprivation includes fasting. Fasting can occur because of religious purposes or from psychological conditions such as anorexia. Fasting refers to the ability to willingly refrain from food and possibly drinks as well. Anorexia, as previously mentioned, is psychological disorder in which the patient is irrationally afraid of gaining weight. Therefore, he or she restricts the intake of calories on a daily basis. Anorexia can lead to seizures due to malnutrition (Hockenbury, Don, and Hockenbury, Sandra, 2008). The dissociation caused by fasting is not only life-threatening but it is the reason why extended fasting periods can lead to ASC. Thus, the temporary dissociation from reality allows fasting to fall into the category of an ASC following the definition provided by Dr. Avner (2006).
Another pathological cause is psychosis, otherwise known as a psychotic episode. In order to comprehend psychosis, it is important to determine what symptoms it implies. Psychotic episodes often include delusions, paranoia, de-realization, depersonalization, and hallucinations (Revonsuo et al., 2008). Studies have not been able to clearly identify when a person is reaching a higher level of risk for a psychotic episode (Schimmelmann, B., Walger, P., & Schultze-Lutter, F.,2013), but the earlier people are treated for psychosis the more likely they are to avoid the devastating consequences which could lead to a psychotic disorder (Schimmelmann, B., Walger, P., & Schultze-Lutter, F., 2013). Unfortunately, there are very few studies which have thoroughly investigated psychotic episodes, and the ability to predict this disorder remains unclear. (Schimmelmann, B., Walger, P., & Schultze-Lutter, F., 2013).
Reviewing the previous conditions for accidental and pathological causes, we can come to understand that all of these accidental or pathological causes share the component of reduced self-awareness. Therefore, ASCs cannot only be caused naturally but they can be induced intentionally with methods including hypnosis meditation, amongst others. There are also ASCs which are caused by less recreational purposes; people who utilize illegal substances, or heavy dosages of medications, as well as large amounts of alcohol can indeed comply with the definition of an ASC (Revonsuo et al., 2008).
Physiological methods of inducing
Pharmacological methods of inducing
An altered state of consciousness may be defined as a short-term change in the general configuration of one’s individual experience, such that the rational functioning is clearly altered from one's usual state of consciousness. (Revonsuo, A., Kallio, S., & Sikka, P. 2009) There are many ways that one’s consciousness can be altered, and drug use is one of them. Psychoactive drugs aid in altering the state of consciousness. Psychoactive drugs can be defined by a chemical substance that passes through the blood and disturbs brain function, causing changes in awareness, attitude, consciousness, and behavior. (Revonsuo, A., Kallio, S., & Sikka, P. 2009)
Marijuana is a psychoactive drug that is known to alter the state of consciousness. Marijuana alters mental activity, memory, and pain perception. One who is under the influence of marijuana may experience degrees of paranoia, increased sensitivity, and delayed reactions not normal for their usual conscious state.
MDMA (ecstasy) is a drug that also alters one’s state of consciousness. The state of consciousness brought about by MDMA ingestion includes a rise in positive feelings and a reduction in negative feelings (Aldridge, D., & Fachner, J. ö. 2005). Users' emotions are increased and inhibitions lowered, often accompanied by a sensation of intimacy or connection with other people.
Opiates are a class of drugs that alter consciousness. Examples of opiates include heroin, morphine, hydrocodone, and oxycodone. Opiates produce analgesia and often feelings of euphoria in users. Opiate abuse may result in decreased production of endorphins in the brain, natural pain relievers whose effects may be heightened by drugs. If one takes a large dose of opiates to compensate for the lack of natural endorphins, the result may be death. (Berridge, V. 2001)
Cocaine alters one’s state of consciousness. Cocaine affects the neurotransmitters that nerves use to communicate with each other. Cocaine inhibits the re-uptake of norepinephrine, serotonin, dopamine, and other neurotransmitters in the synapse, resulting in an altered state of consciousness or a "high." (Aldridge, D., & Fachner, J. ö. 2005).
Lysergic Acid Diethylamide, or LSD, activates serotonin receptors (the amine transmitter of nerve urges) in brain matter. LSD acts on certain serotonin receptors, and its effects are most prominent in the cerebral cortex, an area involved in attitude, thought, and insight, which obtains sensory signs from all parts of the body. LSD’s main effects are emotional and psychological. The ingester's feelings may alter quickly through a range from fear to ecstasy. (Humphrey, N. 2001) This may cause one to experience many levels of altered consciousness.
Alcohol alters consciousness by shifting levels of neurotransmitters. Neurotransmitters are endogenous chemicals that transmit signals across a synapse from one neuron (nerve cell) to another "target" cell (often another neuron). Neurotransmitters can cause inhibitory or excitatory effects on the "target" cell they are affecting. Alcohol increases the effect of the neurotransmitter GABA (Gamma-Aminobutyric acid) in the brain. GABA causes slow actions and inaudible verbal communication that often occur in alcoholics (Berridge, V 2001). Alcohol also decreases the excitatory neurotransmitter glutamate. Suppressing this stimulant results in a similar type of physiological slowdown. In addition to increasing the GABA and decreasing the glutamate in the brain, alcohol increases the amount of the chemical dopamine in the brain, which is one of the addictive causes of alcoholism.
A classification of Altered States of Consciousness is helpful if one wants to compare or differentiate between induced ASCs and other variations of consciousness. An attempt for classification can be found in the graphic (1) which is based on a suggested classification by Schmidt&Majic.
The graphic is not a detailed taxonomy of all the variations of ASCs but it shows in which variety ASCs can occur and the dissociation with reference to their genesis. Sleep- and dream states are distinguished from waking consciousness since they account for substantially different ways of the ability of memory formation and retrieval. Psychiatric diseases that go along with persistent changes of consciousness, like schizophrenia, are covered with the term “pathological conditions”. In contrast to that, the model shows intended and induced ASCs as well as general fluctuations of neurotransmission, which are reversible and short-termed. One step further the graph suggests to split induced ASCs in persistent and reversible states. The differentiation between persistent and reversible altered states is not the only possible subdivision. An alternative is the model of Dieter Vaitl’s who extended the categories. He introduced a scheme based on the genesis and induction of ASCs:
· Spontaneous (day-dreaming and near death experience)
· Physical and physiological (fasting and sex)
· Psychological (music, meditation, hypnosis)
· Pathological (Epilepsy, brain damage)
· Pharmacological (psychoactive substances)
 Empirische Untersuchung veränderter Bewusstseinszustände. T.T. Schmidt, Tomislav Majić. Kapitel 1 und 2
 Veränderte Bewusstseinszustände: Grundlagen – Techniken – Phänomenologie. Dieter Vaitl. Schattauer, 2012, S. 14.
 Empirische Untersuchung veränderter Bewusstseinszustände. T.T. Schmidt, Tomislav Majić. Chapter 1
- Ecstasy (emotion)
- Ecstasy (religious)
- Ego death
- Energy (esotericism)
- Flow (psychology)
- Hydrogen narcosis
- Immersion (virtual reality)
- Kundalini syndrome
- Major depressive disorder
- Music therapy
- Mystical psychosis
- New Age
- Near death experience
- Nitrogen narcosis
- Out-of-body experience
- Peak experience
- Psychedelic drug
- Psychedelic experience
- Psychology of religion
- Religious experience
- Runner's high
- Sexual pleasure
- Sleep deprivation
- Sleep paralysis
- Such as amphetamines, anticholinergic, anticonvulsants, barbiturates, benzodiazepines, clonidine, cocaine, ethanol, haloperidol, narcotics, phenothiazine, salicylates, selective serotonin uptake inhibitors (SSRIs), and tricyclic antidepressants.
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