Results: ID showed reduced P2 amplitudes relative to GSC specifically in phasic REM sleep. The same reduction also correlated with the amount of sleep misperception across groups. Independent component analysis showed a frontal negativity to contribute most to this group difference.
Conclusions: The present finding can be interpreted as increased mismatch negativity (MMN) in ID, reflecting automated detection of change in the auditory system and a concomitant orienting response. Specifically phasic REM sleep appears to be vulnerable to sensory afferences in ID patients, possibly contributing to the perception of being awake.
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 Dr 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".
There is no general definition of an altered state of consciousness, as any definitional attempt would first have to rely on a definition of a normal state of consciousness. Attempts to define the term can however be found in philosophy, psychology and neuroscience. There is no final consensus on what the most accurate definition is. In the following, the best established and latest definitions are provided:
"An altered state is any mental state(s), induced by various physiological, psychological, or pharmacological maneuvers or agents, which can be recognized subjectively by the individual himself (or by an objective observer of the individual) as representing a sufficient deviation in subjective experience of psychological functioning from certain general norms for that individual during alert, waking consciousness."
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.
"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)
Altered states of consciousness might have been employed by humans as early as 30,000 years ago. Mind-altering plants and/or excessive dancing were used to attain an ecstatic or mystic state. Examples of early religious use of altered states of consciousness are the rites of Dionysos and the Eleusinian Mysteries, as well as yoga and meditation. Followers of various shamanic traditions "enter altered states of consciousness in order to serve their community." Terence McKenna has suggested that the use of psychedelic mushrooms in prehistoric times has led to the "evolution of human language and symbol use". Some theorists propose that mind-altering substances, such as Soma, might have pushed the formation of some of the world's main religions.
Due to the behaviourist paradigm in psychology altered states of consciousness were dismissed as a field of scientific inquiry during the early 20th century. They were pathologized and merely seen as symptoms of intoxication or demonic possession.
Their return into psychology began with Wiliam James' interest into a variety of altered states, such as "mystical experiences and drug-induced states". James' investigations into first-person-subjective-experience contributed to the reconsideration of introspection as a valuable research method in the academic community.
A classification of Altered States of Consciousness is helpful if one wants to compare or differentiate between induced ASCs and other variations of consciousness. Various researchers have attempted the classification into a broader framework. The attempts of classification discussed in the following focus on slightly different aspects of ASCs. Several authors suggested classification schemata with regard to the genesis of altered states and with regard to the type of experiences:
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. There are many ways that one's consciousness can be altered, such as by using psychoactive drugs, which are defined as chemical substances that pass through the blood brain barrier and disturb brain function, causing changes in awareness, attitude, consciousness, and behavior.
Cannabis is a psychoactive drug that is known to alter the state of consciousness. Cannabis alters mental activity, memory, and pain perception. One who is under the influence of cannabis may (or may not) experience degrees of paranoia, increased sensitivity, and delayed reactions not normal for their usual conscious state. A 2009 review of anxiety and cannabis studies concluded that "frequent cannabis users appear to have higher levels of anxiety than non-users," and that "a considerable number of subjects developed anxiety disorders before the first symptoms of cannabis dependence." That led researchers to believe that anxiety-prone people tend to use cannabis as a self-prescribed anxiety medicine, opposing the idea that cannabis is what's causing the anxiety.
Cocaine alters one's state of consciousness. Cocaine affects the neurotransmitters that nerves use to communicate with each other. Cocaine inhibits the reuptake 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.
Pathological or accidental induction may 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). Those with personal experience of conditions such as Depersonalisation often cite the opposite, that it is an increased awareness of the environment and the self that results in altered states of consciousness. 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 that 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 altered state of consciousness is experienced.
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 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. This not only altered the patient's behavioral pattern but also made them dissociate from reality during that particular time frame.
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.
Extensive scientific investigation on altered states of consciousness and their relationship to drug interactions with receptors in the brain have been performed. Particularly the study of the neurotransmitter serotonin and the effects of psychedelic drugs on the brain has been intensively researched over the past sixty years. It has been hypothesized that hallucinogens act either as an antagonist or an agonist at serotonin-2A receptors and will elicit a state that shares some common phenomenological features with early acute stages of the group of schizophrenia disorders. 041b061a72