Altered state of consciousness

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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 state of consciousness, referred to as ASC by Ludwig (1966), started as and is stated as any mental state induced by physiological, psychological, or pharmacological maneuvers or agents. Definitions and speculations have formed since Ludwig defined altered state of consciousness, due to many theories and insights that arise from time to time. However, Ludwig is recognized as the first to define the term (Revonsuo, Kallio, & Sikka, 2009). Altered state of consciousness is a change of pattern of the conscious experience, subjective to each individual’s general norms for his or her normal waking state of consciousness (Revonsuo, Kallio, & Sikka, 2009). Consciousness is the state of full alertness with the ability to respond appropriately to environmental stimuli, as defined by Dandan. Altered state of consciousness is recognized by Farthing (1992) as a state in which the ability to perceive and react to environment/stimulants are affected to various degrees. Although, “the definition stated for ASC does not provide an explanatory model of the mechanisms underlying the normal, baseline representational state of consciousness change so as to bring about a misrepresentational state”, it most certainly gives some lead as to what to observe (Revonsuo, Kallio, & Sikka, 2009) . For example, some observable abnormal and sluggish behaviors meet the criteria for altered state of consciousness. Some abnormalities are observable by analyzing mannerisms, responses, and movements. Sluggish behaviors may be observed in eye movement and/ or speech. The brain is mainly affected, and could range from empty thoughts and/or confusion to brain death. Altered state of consciousness is not a disease, but may be a part of a disease process (Dandan, 2004).

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]


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. Altered state of consciousness can be caused by common, but precise causes. Rarely, is altered state of consciousness due to only one non-reactant stem. Some cases are common causes, while others could be very complicated and never unraveled completely. Creativity and focus levels may determine altered state of consciousness based on clarity of views and interpretation. Some causes include emotions, intoxication, spiritual beliefs, and structural lesions. Emotions influence behavior that alters the state of consciousness. Emotions are influenced to feel a variety of feelings (sadness, anger, happiness, love, excitement, jealousy, fearful) through stimulants such as music, humor, visual objects, movies, books, words or phrases. Altered state of consciousness experienced by emotion stimulants is particular and subjective. (Altarriba, 2012) An example of altered state of consciousness by emotion stimuli is an adolescent experiencing a love relationship for the first time. The adolescent may listen to music and be completely lost in thought and present sluggish eye and sluggish speech. Intoxication take account of ingestion of agents, such as amphetamines, anticholinergic, anticonvulsants, barbiturates, benzodiazepines, clonidine, cocaine, ethanol, haloperidol, narcotics, phenothiazine, salicylates, selective serotonin uptake inhibitors (SSRIs), and tricyclic antidepressants. (Avner, 2006) Spiritual beliefs enclose concentration of thoughts through meditation, and spiritual or mystical rituals, for the removal of bad spirits that may cause altered state of consciousness. Structural lesions are composed of trauma (intracranial hematoma, cerebral contusions, diffuse axonal injury), infection (abscess, meningitis, encephalitis), tumors (vascular, subarachnoid hemorrhage (SAH), arteriovenous malformation (AVM), aneurysms, ischemia, infarcts), metabolic ( hypoxia, hypercarbia, hypoglycemia, hyperglycemia, hyponatremia, hypernatremia, hypothyroidism, hepatic encephalopathy, uremic encephalopathy, addisonian crisis, electrolyte disorders, endocrine abnormalities), and other causes (hypothermia, hypotension/ shock, psychogenic). (Dandan, 2004) It is important to understand there are sometimes two or more causes that lead to altered state of consciousness. For example, a person with altered state of consciousness and a comorbid diagnosis of depression and substance abuse, it is of primary importance to understand that there may be a possibility the person is at an altered state of consciousness because of a side effect of a substance. Altered state of consciousness is 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[edit]

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).[7] 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 or even 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 ACS is experienced (Spikman et al. 2013).[8]

Another common cause is epilepsy, according to Medlineplus[9] 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)[10] 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 experienced hallucinations while a seizure is occurring (Korsnes M, Hugdahl K, Nygard M, Bjornæs H, 2010).[11] 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 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 nitrous oxide for 10 minutes. The study confirmed that inhaling substances other than oxygen results in impaired self-awareness, which can produce ACS (1976).[12]

In addition to oxygen deprivation or deficiency, infections are a common pathological cause of ACS. A prime example of an infection includes meningitis. The medical website WEBMD [13] 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 ACS 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 ACS 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.[14] 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.[15] 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 ACS. Thus, the temporary dissociation from reality allows fasting to fall into the category of an ACS following the definition provided by Dr. Avner (2006).

Lastly 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, de-realization, depersonalization, and hallucinations (Revonsuo et al., 2008). Even with these symptoms 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).[16] The earlier people are treated for psychosis the more likely they are to avoid the devastating consequences that could lead to a psychotic disorder (Schimmelmann, B., Walger, P., & Schultze-Lutter, F., 2013)[16] Unfortunately, there are very few studies that have thoroughly investigated psychotic episodes. The one symptom that is very clear is the fact that it happens for a brief moment intermittently throughout a person’s life span. However, the ability to predict this disorder remains unclear. (Schimmelmann, B., Walger, P., & Schultze-Lutter, F., 2013).[16]

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 ACSs cannot only be caused naturally but they can be induced intentionally with methods that include hypnosis meditation amongst others. But there are ACSs that are caused by less recreational purposes; people who utilize illegal substances, or heavy dosage of medications, as well as large amounts of alcohol can indeed comply with the definition of an ACS (Revonsuo et al., 2008).

Other causes[edit]

Spiritual and religious[edit]

An ASC can sometimes be reached by meditation, prayer, or disciplines (e.g. Mantra Meditation, Yoga, Sufism, dream yoga).


An ASC can sometimes be reached intentionally by the use of sensory deprivation, an isolation tank, lucid dreaming and hypnosis.

Psychoactive drugs[edit]

An altered state of consciousness may be defined as a short-term change in the general configuration of one’s individual experience, such that one believing that their rational functioning is clearly altered from certain overall norms of their 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 aides 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 enhances mental activity, memory and also alters pain perception. One who is under the influence of Marijuana may experience paranoia, sensory sensitivity and also delayed reaction that is not the norm for their usual conscious state.

MDMA: Methylenedioxymethamphetamine (Ecstasy) is drug that also alters one’s state of consciousness. MDMA releases serotonin and can bring about some individual effects when ingested. Persons who take Ecstasy typically want to feel like they are on "cloud 9" (A feeling of total bliss). This state of consciousness often range from a rise in positive feelings and a reduction in negative feelings (Aldridge, D., & Fachner, J. ö. 2005). The person's emotions are increased as well as becoming more outgoing and having a sensation of intimacy or connection with other people. Also, there is a decrease in self-awareness as well as their awareness and an increase in sensitivity.

An opiate is also a drug that alters consciousness. Examples of opiates include heroine, morphine, vicodin, and oxycodone. Opiates numb the senses and cause a false state of consciousness and satisfaction. Opiates also harmfully disturb the interaction of the brain by slowing down and sometimes stopping the construction of its own natural opiates, named endorphins. Endorphins are 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 gets in the way of norepinephrine, serotonin, dopamine, and other neurotransmitters from being absorbed. This chemical buildup between nerves results in an altered state of consciousness or a "high." (Aldridge, D., & Fachner, J. ö. 2005). Lysergic Acid Diethylamide LSD blocks serotonin (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 physical. The consumer's feelings may alter quickly through a range of 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 transport chemicals throughout the body that controls the thinking process, performance and feeling. Neurotransmitters either motivate brain electrical activity, or reduce brain electrical activity. Alcohol increases the effect of the neurotransmitter (GABA Gamma-Aminobuturic 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 creates the mood of satisfaction that occurs when one takes a drink.


Dreams are a structural conception that leads to a formulation of the dream as one output of a precise memory systems, by emotional assessment, operating under programs that are specific to sleep (Breger, 1967, p. 2).A dream is defined as an illusion of the imagination in which figures are reproduced (Calkins, 1983, p. 323).Real thoughts, though are often denied and elements of dreams involve sense perception that occur in dreams (Calkins, 1983, p. 325/334). Dreams consist of multimodal sensory qualities, visual imagery, and have realistic sensations. They are a unique consolidation of internally subjective experiences and delusions (Noreika & Windt, 2011, p. 1100/1103). Dreams are experiences that occur during sleep that we often recall waking up. Dreams are sensations, impressions, and thoughts that are composed into narratives or experiences (Dennett, 1976, p. 151) where various kinds of consciousness are present (Bosinelli, 1995, p. 198). Dreams are composed and presented in fast intervals with full consciousness (Dennett, 1976, p. 158). The problem of consciousness is that subjective and cognitive theories have often been discussed by neuroscientists, philosophers, and psychologists (Cicogna & Bosinelli, 2001, p. 26). Many research reflections and studies about consciousness have considered the possibility whether there are more than one nervous structure for consciousness (p. 27). Primary consciousness is the direct experience of feelings, thoughts, and memories. It includes spontaneous images, memories, and thoughts (p. 27). Phenomenal awareness which is one of the two types of consciousness during sleep is considered to be the primary consciousness. This is where reflective consciousness is ineffective and the dreamer is not aware that he or she is dreaming (p. 29).Dreaming is a significant connection for general ideas of consciousness that shows that a complicated form of consciousness can input processes and behavioral functioning under changed conditions. Dreams show a pattern through conscious experience by brain activation rather than responsiveness and external stimuli delusions (Noreika & Windt, 2011, p. 1101) The second form of conscious during sleep is meta-awareness. This is defined as all forms of cognition on primary awareness (Cicogna & Bosinelli, 2001, p. 27) which is usually absent during sleep (p. 29). The functioning of consciousness as meta-awareness can explain the oddness of one's dream. The experience which is logically or factually impossible, but that in fact is connected with feeling towards highly irregular events or images (p. 29). This corresponds to the most leading level indicated as self-reflectiveness. This implies that the action of the dreamer consciously follows on the fact that he or she is dreaming (p. 28). This kind of experience is called lucid dreaming, which is current in our Dream Data Bank (p. 29) Lucid dreams not only knows that he or she is dreaming, but can also remember facts of his or her waking life and engage in dream control delusions (Noreika & Windt, 2011, p. 1103) Dreams occur during the third state of existence, which is in the REM (rapid eye movement) sleep. This is a proven biological state of cyclic found in all humans and all mammals. The neural mechanisms involved are primitive, which suggest that the REM state is an important biological process. One of the functions of REM concerns the role of endogenous stimulation in early development of the central nervous system (CNS). This state serves important developmental functions especially during the early infancy and utero stage(Breger, 1967, p. 2). This is characterized by immense levels of brain activation delusions (Noreika & Windt, 2011, p. 1094). During the REM state of activation, memory systems guide output which takes the form of emotional arousal, visual images, responses, and effective experiences. This sleep state uses regressed programs which lead to the openings of the system by combining and transforming symbolizing modes. The dream then becomes a prosperous source of information for a particular individuals memory systems. This system is organized with specific memories, fantasies, and associations of the basic dimensions of the system (Breger, 1967, p. 22). The loss of reality during dreams is due to various circumstances. The main cause, however, is the lack of control sources that turn on the closing of both sensory input and motor output (Cicogna & Bosinelli, 2001, p. 28). Since dreaming is a form of psychological activity that develops in the absence of stimulus input, it should be suited to internal transformations of stored material (Breger, 1967, p. 24). Individuals go to sleep with certain memory systems of readiness that is due to emotional arousal. An image of such aroused information is between waking and dreaming during the hypnagogic period that usually occurs during sleep (p. 26). All dreams are composed into memory banks, which depends on various factor; waking stimulus, precedence of composition, and the degree of repression (p. 159). In most dreams, the dreamer always participates in the event, and hallucinations of oneself does not allow a clear view between waking self-awareness and dreaming (Cicogna & Bosinelli, 2001, p. 31). Self-awareness during dreaming is limited to episodic situations of the oneiric context. This is the mechanisms of judgment and self-regulation, which access all the subject's knowledge that seem to be nonfunctioning (p. 32). Dreams are coherent and realistic loaded with symbolism. Dreamer's knowledge of his or her recent and distant experiences are guided by fears and desires, covert and overt (Dennett, 1976, p. 156).


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 wave patterns have not been heavily studied; however, they may be connected to intense meditative states.[citation needed]
Delta brainwave patterns characterize slow wave sleep.
Theta waves are produced between dreams, and represent an "interlude" between dreams. The waves tend to last 15–30 minutes between REM states.
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[edit]


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  2. ^ Ludwig, Arnold M. (September 1966). "Altered States of Consciousness (presentation to symposium on Possession States in Primitive People)". Archives of General Psychiatry 15 (3): 225. doi:10.1001/archpsyc.1966.01730150001001. Retrieved 29 September 2010. 
  3. ^ Tart, Charles T. (1969). Altered States of Consciousness: A Book of Readings. New York: Wiley. ISBN 0-471-84560-4. 
  4. ^ Tart, Charles T. (2001). States of Consciousness. ISBN 0-595-15196-5. 
  5. ^ Lombardo GT (2007). "An inquiry into the sources of poetic vision: Part I – the path to inspiration". J Am Acad Psychoanal Dyn Psychiatry 35 (3): 351–71. doi:10.1521/jaap.2007.35.3.351. PMID 17907906. 
  6. ^ Spivak D (1999). "Altered states of society: a tentative approach". A World in Transition: Humankind and Nature (Dordrecht: Kluwer Academic Publishers): 33–42. 
  7. ^ "Altered states of consciousness.". Pediatrics in Review. 27(9):331-8, 2006. Retrieved 5 December 2013. 
  8. ^ Deficits in Facial Emotion Recognition Indicate Behavioral Changes and Impaired Self-Awareness after Moderate to Severe Traumatic Brain Injury (Plos ONE, 8(6),). 2013. pp. 1–7. doi:10.1371/journal.pone.0065581. 
  9. ^ "Epilepsy". Retrieved 5 December 2013. 
  10. ^ Revonsuo, A., Kallio, S., & Sikka, P. (2009). Philosophical Psychology, (22(2)): 187–204. doi:10.1080/09515080902802850. 
  11. ^ Korsnes, M., Hugdahl, K., Nygård, M., & Bjørnæs, H. (2010). "An fMRI study of auditory hallucinations in patients with epilepsy.". Epilepsia. Series 4 (51(4)): 610–617. doi:10.1111/j.1528-1167.2009.02338.x. 
  12. ^ 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. 
  13. ^ "Meningitis - Topic Overview". 8 December 2013. Retrieved 5 December 2013. 
  14. ^ "Harvard Heart Letter". Harvard Health Publications. 31 May 2012. Retrieved 5 December 2013. 
  15. ^ Nogal, Powel; Lewiński,Andrzej (January 2008). "Anorexia Nervosa". Journal of Endocrinology 59 (2): 148–155. 
  16. ^ a b c Schimmelmann, B., Walger, P., & Schultze-Lutter, F. (2013). "The Significance of At-Risk Symptoms for Psychosis in Children and Adolescents". Canadian Journal Of Psychiatry 58 (1): 32–40. 

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Further reading[edit]