Altered States of Consciousness

An altered state of consciousness (ASC),[1] also called altered state of mind, is any condition which is significantly different from a normal waking beta wave state. The expression was used as early as 1966 by Arnold M. Ludwig[2] and brought into common usage from 1969 by Charles Tart.[3][4] It describes induced changes in one's mental state, almost always temporary. A synonymous phrase is "altered state of awareness".

Altered states of consciousness can be associated with artistic creativity[5] or different focus levels. They also can be shared interpersonally and studied as a subject of sociological research.[6]

Causes of Altered States of Consciousness

When analyzing altered states of consciousness an important facet is determining how the altered state arises. There are multiple ways to experience altered states of consciousness, which include the following: Accidental and Pathological, Intentional, Recreational, Spiritual, and lastly Religious.

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 is that it begins with a reduced self-awareness followed by reduced awareness in the environment. (2006) As a result when the reduced self-awareness and environmental awareness take effect the following conditions are produced altered states of consciousness. To explain accidental and pathological causes the specific conditions below provide clarity on the types of conditions that fall into this particular category.

  • Traumatic Experience

The first is traumatic experience is defined as a lesion cause by an external force (Trauma. (n.d.) In Merriam Webster Dictionary online, 2013) examples can include an impact to the brain by a blunt force or even a car accident. The reason a traumatic experience causes altered states of consciousness is because it will change how the brain works. The external impact will divert 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) Hence when the damage becomes uncontrollable the patient experiences changes in behavior and impaired self-awareness which is exactly when an ASC is experienced (Spikman et al 2013).

  • Epilepsy

Another common cause is epilepsy according to Medlineplus describes 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 a loss of mental control (Revonsuo, Chaplin, and Wedlund, 2008). This concept continues to comply with the definition of what an ASC is.

  • Oxygen Deficiency

The next item of interest is oxygen deficiency; following the definition of ASC questioning how oxygen deficiency impacts the brain is an important part of comprehending why ACS 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 only nitrous oxide for 10 minutes. The study confirmed that when oxygen is not the only substance inhaled impaired self-awareness can produce ASC (1976).

  • Infections

In addition to oxygen deprivation or deficiency infections are a common pathological cause to ASC. A prime example of infections includes meningitis. Meningitis is according to the medical website WEBMD states that meningitis is an infection that causes the coverings of the brain to swell. This particular infection will occur in children to young adults. This infection is divided into two main types. There is bacterial and viral. The Meningitis that will cause ASC is the viral with symptoms that include fevers and seizures (2010). The moment seizures begin to occur that is when the impairment becomes visible and the patient enters the altered state of consciousness.

  • Sleep Deprivation

Furthermore another type of deprivation that can cause ASC includes sleep deprivation. This refers to the loss of sleep that will provoke possible seizures, causes 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 will impact the brain as well. A Harvard Medical school study conducted in 2007 also indicated with the use of MRI that the brain with sleep deprivation was not capable of being in control. Therefore there was impairment specifically to the patient’s self-awareness. Not only to the patient’s self-awareness they were also prone to be a lot clumsier than if had they not been experiencing sleep deprivation.

  • Fasting

Coupled with deprivation of sleep and oxygen, another form of deprivation includes fasting. Fasting can be for religious purposes or from psychological conditions such as anorexia. Fasting refers to the ability to willingly refrain from food and possibly drinks as well. But conditions like Anorexia as previously mentioned is psychological disorder in which the patient is irrationally afraid of gaining weight. Therefore he or she restricts their intake of calories on a daily basis. Anorexia can lead to seizures due to the malnutrition (Hockenbury, Don, and Hockenbury, Sandra, 2008). This temporary dissociation from reality is the reason why extended fasting periods can lead to ASC and ultimately if left untreated can cause death.

  • Psychosis

Lastly reviewing another pathological cause is psychosis otherwise known as a psychotic episode. In order to comprehend psychosis it is important to determine what symptoms it also implies. Psychotic episodes often include delusions, paranoia, derealization, depersonalization and hallucinations (Revonsuo et al, 2008).

Reviewing the previous conditions for accidental and pathological causes we can come to understand that all of these accidental or pathological causes all share the component of reduced self-awareness. Therefore ASCs can not only because naturally but they can be induced intentionally with methods that include hypnosis meditation amongst others. But there are ASCs that are not only cause by these positive recreational purposes; people do utilize illegal substances, or heavy dosage of medications, as well as a large amount of alcohol can indeed comply with the definition of an ASC (Revonsuo et al, 2008).


An ASC can sometimes be reached intentionally by the use of sensory deprivation, an isolation tank, sleep deprivation, lucid dreaming, hypnosis, meditation, prayer, or disciplines (e.g. Mantra Meditation, Yoga, Sufism, dream yoga.)

ASCs can also be attained through the ingestion of psychoactive drugs such as alcohol and opiates, but more commonly with traditional hallucinogens of indigenous cultures, such as cannabis, dimethyltryptamine, psilocybin mushrooms, Peyote and Ayahuasca. Other modern hallucinogens that some attempt to use for a similar purpose are for example, (D)-methorphan, Lysergic acid diethylamide or one of the drugs belonging to the classes of substituted tryptamines, substituted phenethylamines and substituted amphetamines.

States of consciousness


During an altered state of consciousness, brain waves occupy different categories of frequencies (i.e. Epsilon, Delta, Theta, Alpha, Beta, Gamma). These waves can be measured using an Electroencephalograph (EEG). Below is a list of wave types, along with their corresponding frequencies and states of consciousness:

  • Epsilon: 0.00–0.05 Hz
Epsilon wave patterns have not been heavily studied; however, they may be connected to intense meditative states.
Delta brainwave patterns characterize slow wave sleep.
  • Theta: 4–8 Hz Normal deep sleep state.
Theta waves are produced between dreams, and represent an "interlude" between dreams. The waves tend to last 15–30 minutes between REM states.
  • Alpha: 8–12 Hz Typical dream state.
Alpha waves can be seen in persons watching movies or television narratives in which they are fully engrossed, mostly unaware of their surroundings.
Beta waves correspond to normal conscious brain activity, ranging from calm and relaxed consciousness, to fight-or-flight panic.
As the ability to measure brainwave frequency has significantly improved with advances in digital technology, it has become possible and practical to measure brainwave frequencies beyond 30 Hz. As more is learned about these brainwaves, a change in classifications may occur. The beta-wave level of consciousness seems to extend well beyond 30 Hz, but frequencies of 90 Hz or more (gamma waves), are shown to be associated with coordination of signals across longer distances within the brain, facilitating the completion of complex actions or associations which require the simultaneous use of multiple brain regions.

See also


1. Connor, C., Birchwood, M., Palmer, C., Channa, S., Freemantle, N., Lester, H., & ... Singh, S. (2013). Don't turn your back on the symptoms of psychosis: a proof-of-principle, quasi-experimental public health trial to reduce the duration of untreated psychosis in Birmingham, UK. BMC Psychiatry, 13(1), 1-6. doi:10.1186/1471-244X-13-67

2. Edwards, D., Harris, J. A., & Biersner, R. (1976). ENCODING AND DECODING OF CONNECTED DISCOURSE DURING ALTERED STATES OF CONSCIOUSNESS. Journal Of Psychology, 92(1), 97.

3. Revonsuo, A., Kallio, S., & Sikka, P. (2009). What is an altered state of consciousness?. Philosophical Psychology, 22(2), 187-204. doi:10.1080/09515080902802850

4. Englot, D., Rutkowski, M., Ivan, M., Sun, P., Kuperman, R., Chang, E., & ... Auguste, K. (2013). Effects of temporal lobectomy on consciousness-impairing and consciousness-sparing seizures in children. Child's Nervous System, 29(10), 1915-1922. doi:10.1007/s00381-013-2168-7

5. Spikman, J. M., Milders, M. V., Visser-Keizer, A. C., Westerhof-Evers, H. J., Herben-Dekker, M., & van der Naalt, J. (2013). Deficits in Facial Emotion Recognition Indicate Behavioral Changes and Impaired Self-Awareness after Moderate to Severe Traumatic Brain Injury. Plos ONE, 8(6), 1-7. doi:10.1371/journal.pone.0065581

6. Meningitis - Topic Overview( 2010, December 8) from:

7. "Harvard Heart Letter examines the costs of not getting enough sleep – Harvard Health Publications". 31 May 2012. Retrieved 2012-08-13.


9. Avner JR: Altered states of consciousness. Pediatrics in Review. 27(9):331-8, 2006.

10. Taheri S, Lin L, Austin D, Young T, Mignot E (December 2004). "Short Sleep Duration Is Associated with Reduced Leptin, Elevated Ghrelin, and Increased Body Mass Index". PLoS Med. 1 (3): e62. doi:10.1371/journal.pmed.0010062. PMC 535701. PMID 15602591.

11. Nogal, Powel; Lewiński,Andrzej (01.03.2008). "Anorexia Nervosa". Endokrynologia Polska/Polish Journal of Endocrinology 59 (2): 148–155. ISSN 0423-104X.

Further reading

  • Bourguignon, Erika (1973). Religion, Altered States of Consciousness, and Social Change. Ohio State Univ. Press, Columbus. Full text
  • Hoffman, Kay (1998). The Trance Workbook: Understanding and Using the Power of Altered States. Translated by Elfie Homann, Clive Williams, and Dr. Christliebe El Mogharbel. Translation edited by Laurel Ornitz. ISBN 0-8069-1765-2
  • expand by hand
  • James, William (1902). The Varieties of Religious Experience ISBN 0-14-039034-0
  • Roberts, T.B. (Ed.) (2001). Psychoactive Sacramentals: Essays on Entheogens and Religion. San Francisco: Council on Spiritual Practices. ISBN 1-889725-02-1
  • Roberts, T.B. and P.J. Hruby. (1995–2002). Religion and Psychoactive Sacraments: An Entheogen Chrestomathy . ISBN 1-889725-00-5
  • Roberts, T.B. "Chemical Input—Religious Output: Entheogens." Chapter 10 of Where God and Science Meet: Vol. 3: The Psychology of Religious Experience. Edited by Robert McNamara. Westport, CT: Praeger/Greenwood, 2006. ISBN 0-275-98788-4
  • Weinel, Jonathan (August 2010). "Canadian Electroacoustic Community.
  • Weinel, Jonathan (2012). "Altered States of Consciousness as an Adaptive Principle for Composing Electroacoustic Music". Unpublished PhD Thesis.
  • Wier, Dennis R. (1995) Trance: From Magic to Technology. Transmedia. ISBN 1-888428-38-4

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