Altered state of consciousness

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. == Definitions ==

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. The best-established and latest definitions are provided below. Arnold M. Ludwig attempted a first definition in 1966. Starting from this, Charles Tart focuses his definition on the subjective experience of a state of consciousness and its deviation from a normal waking state. 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 behavioral changes and physiological response. He lists fourteen dimensions of changed subjective experience. To account for an ASC, multiple dimensions need to be altered. A working definition for empirical research based on these previous definitions was by Schmidt in 2016: == History ==

History of utilization of ASCs Altered states of consciousness might have been employed by humans as early as 30,000 years ago. Examples of early religious use of altered states of consciousness are the rites of Dionysus and the Eleusinian Mysteries, as well as yoga and meditation. Some theorists propose that mind-altering substances, such as soma, might have pushed the formation of some of the world's main religions. Meditation in its various forms is being rediscovered by modern psychology because of its therapeutic potential and its ability to "enable the activity of the mind to settle down". In psychotherapy, techniques like hypnosis and meditation support psychological processes. History of scientific study 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 William James's interest into a variety of altered states, such as "mystical experiences and drug-induced states". Foundations for the research have been laid out by various scientists such as Abraham Maslow, Walter N. Pahnke, Stanislav Grof and Charles Tart. They focused on seemingly beneficial aspects of ASCs such as their potential to "promote creativity or treat addiction". Abraham Maslow's research on peak experiences, as moments of "highest happiness and fulfillment", He also called for "state specific sciences" in which researchers should do science on ASCs from within such states. == Classification ==

, are covered with the term "pathological conditions". In contrast, the classification scheme includes intended and induced ASCs as well as general fluctuations of neurotransmission, which are reversible and short-termed. One step further the graph suggests splitting induced ASCs in persistent and reversible states. Translated from German Schmidt & Majic. to distinguish ASCs according to how they were induced: • Pathological (Epilepsy, brain damage) • Pharmacological (psychoactive substances) • Physical and physiological (fasting and sex) • Psychological (music, meditation, hypnosis) • Spontaneous (day-dreaming and near death experience) Vaitl further suggests four basic aspects of experiences: (1) activation (2) awareness span (3) self-awareness (4) sensory dynamics. Alternatively Roland Fischer Within this framework, many ASCs (psychedelics, hypnosis, meditation, etc.) are defined as belonging to the integrative mode. == Induction methods ==

Pharmacological 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. 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. Opioids are a class of drugs that alter consciousness. Examples of opioids include heroin, morphine, hydrocodone, and oxycodone. Opioids produce analgesia and often feelings of euphoria in users. Opioid abuse may result in decreased production of endorphins in the brain, natural pain relievers whose effects may be heightened by drugs. 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. It has also been shown to induce ego death (or ego dissolution). 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. Pathologies/other Pathological or accidental induction may refer to unforeseen events or illnesses. According to Jeffrey R. Avner, professor of clinical pediatrics, a crucial element to understanding accidental and pathological causes of altered states of consciousness (ASCs) 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. Traumatic experience 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. Epilepsy Another common cause of ASCs is epilepsy. According to Medlineplus epilepsy is as a brain disorder that causes seizures (2013). During the seizure, 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 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. Oxygen deficiency Oxygen deficiency impacts the brain, which is why ASCs can occur when there is oxygen deprivation in an environment. Infections In addition to oxygen deprivation or deficiency, infections are a common pathological cause of ASC. A prime example of an infection is 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. Sleep deprivation Sleep deprivation is also associated with ASCs, and can provoke seizures due to fatigue. Sleep deprivation can be chronic or short-term depending on the severity of the patient's condition. Many patients report hallucinations because sleep deprivation impacts the brain. An MRI study conducted at Harvard Medical School in 2007 found that a sleep-deprived brain was not capable of being in control of its sensorimotor functions, leading to impaired self-awareness. Patients were also much clumsier than if they had not been experiencing sleep deprivation. Fasting Fasting is another form of deprivation. Fasting can be deliberate, including for religious reasons or from psychological conditions such as anorexia. Fasting refers to the ability to willingly refrain from food and possibly drinks as well. 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 Avner (2006). Psychosis Another pathological cause is psychosis, otherwise known as a psychotic episode. Psychotic episodes often include delusions, paranoia, derealization, 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). == Neurobiological models of altered state experiences ==

Entropic brain hypothesis The entropic brain hypothesis by Robin Carhart-Harris in 2014 is a theory informed by neuroimaging research that uses the hallucinogen-induced neurological state to make inferences about other states of consciousness. The expression "entropy" is applied here in the context of states of consciousness and their associated neurodynamics, where high entropy means a high level of disorder. The theory proposes a general distinction between two fundamentally different modes of cognition, referred to as primary and secondary consciousness. Primary consciousness is associated with unconstrained cognition and less ordered (higher-entropy) neurodynamics that preceded the development of modern, normal waking consciousness in adults. Examples include the rapid eye movement sleep (REM), transcendental state between REM sleep and sensory awareness(the psychedelic state), or the onset phase of psychosis. Secondary consciousness is associated with constrained cognition and more ordered neurodynamics. Examples include normal waking consciousness, the anesthetized or the depressed state. The theory further proposes that via pharmacological induction of psychedelic substances psilocybin, the brain is able to enter into the primary state of consciousness (the psychedelic state) from normal waking consciousness. This "phase transition" between these two fundamentally different poles of consciousness is facilitated by a collapse of the normally highly organized activity within the default mode network (DMN) and a decoupling between the DMN and the medial temporal lobes (MTLs), which are normally significantly coupled. Findings implicate that abnormalities of serotonin function and the serotonergic system could be responsible for psychiatric disorders such as the spectrum of schizophrenia (gating) disorders and therefore, that serotonin agonist or antagonists might be useful in the treatment of disorders such as schizophrenia. To investigate the underlying causative neurotransmitter mechanisms of this phenomenon, the CSTC (cortico-striato-thalamo-cortical) loop model has been formulated based on empirical neurobiological work. It is indicated that the common hypofrontality (underactivation of frontal brain regions) and cortical activation pattern induced by serotonergic and glutamatergic hallucinogens is due to a common disruption of thalamic gating of sensory and cognitive information. The CSTC feedback loop plays a major role in gating or filtering out external and internal information to the cortex. Thereby it influences the regulation of the level of awareness and attention. Disruption of the CSTC loop system is proposed to significantly influence information processing, for instance the ability to screen out, inhibit, filter, or gate extraneous stimuli and to direct selective attention to salient features of the environment. Failures of these attentional gating mechanisms might overload patients with the excessive processing of both sensory and cognitive stimuli, which could lead to a breakdown of cognitive integrity and difficulty in distinguishing self from non-self and failure to integrate an overwhelming flood of information. Descriptive elaboration of the mentioned effects can be found in the literature on schizophrenia as well as in descriptions of hallucinogenic drug action. Despite strong evidence linking serotonin and psychosis, novel research indicates that some behavioral effects of drugs such as psilocybin appear to be independent of the classical 5-HT2A receptor-agonist actions, implying that the model described here is not the only underlying framework at play. Interdisciplinary research enterprises have set out to study the convergence of serotonergic and glutamatergic models of psychosis and dynamic neurotransmitter interactions, derived from the study of hallucinogenic drugs, in the future. This understanding of synthetic surprise has significant implications for the clinical use of psychedelic substances. The ability of psychedelics to induce surprise is proposed to be central to their therapeutic potential, especially in disrupting maladaptive cognitive and perceptual patterns. ==See also==