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Hallucinations
A hallucination is a perception in the absence of an external stimulus that has the compelling sense of reality. They are distinguishable from several related phenomena, such as dreaming ( REM sleep), which does not involve wakefulness; pseudohallucination, which does not mimic real perception, and is accurately perceived as unreal; illusion, which involves distorted or misinterpreted real perception; and mental imagery, which does not mimic real perception, and is under voluntary control. Hallucinations also differ from " delusional perceptions", in which a correctly sensed and interpreted stimulus (i.e., a real perception) is given some additional significance. Hallucinations can occur in any sensory modality— visual, auditory, olfactory, gustatory, tactile, proprioceptive, equilibrioceptive, nociceptive, thermoceptive and chronoceptive. Hallucinations are referred to as multimodal if multiple sensory modalities occur. A mild form of hallucination is known as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dementia With Lewy Bodies
Dementia with Lewy bodies (DLB) is a type of dementia characterized by changes in sleep, behavior change (individual), behavior, cognition, movement, and dysautonomia, regulation of automatic bodily functions. Unlike some other dementias, memory loss may not be an early symptom. The disease progressive disease, worsens over time and is usually diagnosed when cognitive impairment interferes with activities of daily living, normal daily functioning. Together with Parkinson's disease dementia, DLB is one of the two Lewy body dementias. It is a common form of dementia, but the prevalence is not known accurately and many diagnoses are missed. The disease was first described on autopsy by Kenji Kosaka (psychiatrist), Kenji Kosaka in 1976, and he named the condition several years later. REM sleep behavior disorder (RBD)—in which people lose the muscle paralysis (atonia) that normally occurs during Rapid eye movement sleep, REM sleep and act out their dreams—is a core feature. RBD ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Visual Release Hallucinations
Visual release hallucinations, also known as Charles Bonnet syndrome or CBS, are a type of psychophysical visual impairment, visual disturbance in which a person with partial or severe blindness experiences visual hallucinations. First described by Charles Bonnet in 1760, the term ''Charles Bonnet syndrome'' was first introduced into English-speaking psychiatry in 1982. A related type of hallucination that also occurs with lack of visual input is the closed-eye hallucination. Signs and symptoms People with significant vision loss may have vivid recurrent visual hallucinations (fictive visual percepts). One characteristic of these hallucinations is that they usually are "lilliputian hallucination, lilliputian" (hallucinations in which the characters or objects are smaller than normal). Depending on the content, visual hallucinations can be classified as either simple or complex. Simple visual hallucinations are commonly characterized by shapes, photopsias, and grid-like patterns. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pseudohallucination
A pseudohallucination (from + ''hallucination'') is an involuntary sensory experience that is vivid enough to be perceived as a hallucination, but is recognised by the individual as subjective and lacking objective reality. History The concept of pseudohallucination has evolved over time, with its interpretation varying throughout its historical development. The term "pseudohallucination" appears to have been coined by German psychiatrist Friedrich Wilhelm Hagen. Hagen published his 1868 book ''Zur Theorie der Halluzination'', to define them as "illusions or sensory errors". The term was further explored by the Russian psychiatrist Victor Kandinsky (1849–1889). In his work ''On Pseudohallucinations'' (), Kandinsky described his psychotic experiences, defining pseudohallucinations as "subjective perceptions similar to hallucinations in terms of their character and vividness, but distinct from true hallucinations as they lack objective reality." As an example of pseudohalluci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sleep Paralysis
Sleep paralysis is a state, during waking up or falling asleep, in which a person is conscious but in a complete state of full-body paralysis. During an episode, the person may hallucinate (hear, feel, or see things that are not there), which often results in fear. Episodes generally last no more than a few minutes. It can reoccur multiple times or occur as a single episode. The condition may occur in those who are otherwise healthy or those with narcolepsy, or it may run in families as a result of specific genetic changes. The condition can be triggered by sleep deprivation, psychological stress, or abnormal sleep cycles. The underlying mechanism is believed to involve a dysfunction in REM sleep. Diagnosis is based on a person's description. Other conditions that can present similarly include narcolepsy, atonic seizure, and hypokalemic periodic paralysis. Treatment options for sleep paralysis have been poorly studied. It is recommended that people be reassured that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypnagogia
Hypnagogia is the transitional state from wakefulness to sleep, also defined as the waning state of consciousness during the onset of sleep. Its corresponding state is '' hypnopompia'' sleep to wakefulness. Mental phenomena that may occur during this "threshold consciousness" include hallucinations, lucid dreaming, and sleep paralysis. Etymology In 1848, Alfred Maury introduced the term "hypnagogic" from the Greek words ύπνος (“hypnos”), meaning “sleep”, and αγωγός (“agōgos”), meaning “conductor” or “leader”. Later, in 1904, Frederic Myers coined the term "hypnopompic," with its word-ending originating from the Greek word "pompos," meaning "sender." Definitions The word ''hypnagogia'' is sometimes used in a restricted sense to refer to the onset of sleep, and contrasted with '' hypnopompia'', Frederic Myers's term for waking up. However, ''hypnagogia'' is also regularly employed in a more general sense that covers both falling asleep and wa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sensory Deprivation
Sensory deprivation or perceptual isolation is the deliberate reduction or removal of stimuli from one or more of the senses. Simple devices such as blindfolds or hoods and earmuffs can cut off sight and hearing, while more complex devices can also cut off the sense of smell, touch, taste, thermoception (heat-sense), and the ability to know which way is down. Sensory deprivation has been used in various alternative medicines and in psychological experiments (e.g. with an isolation tank). When deprived of sensation, the brain attempts to restore sensation in the form of hallucinations. Short-term sessions of sensory deprivation are described as relaxing and conducive to meditation; however, extended or forced sensory deprivation can result in extreme anxiety, hallucinations, bizarre thoughts, and depression. A related phenomenon is perceptual deprivation, also called the Ganzfeld effect. In this case a constant uniform stimulus is used instead of attempting to remov ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Schizophrenia
Schizophrenia () is a mental disorder characterized variously by hallucinations (typically, Auditory hallucination#Schizophrenia, hearing voices), delusions, thought disorder, disorganized thinking and behavior, and Reduced affect display, flat or inappropriate affect. Symptoms Prodrome, develop gradually and typically begin during young adulthood and rarely resolve. There is no objective diagnostic test; diagnosis is based on observed behavior, a psychiatric history that includes the person's reported experiences, and reports of others familiar with the person. For a diagnosis of schizophrenia, the described symptoms need to have been present for at least six months (according to the DSM-5) or one month (according to the ICD-11). Many people with schizophrenia have other mental disorders, especially mood disorder, mood, anxiety disorder, anxiety, and substance use disorders, substance use disorders, as well as obsessive–compulsive disorder (OCD). About 0.3% to 0.7% of peo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Psychedelics
Psychedelics are a subclass of hallucinogenic drugs whose primary effect is to trigger non-ordinary mental states (known as psychedelic experiences or "trips") and a perceived "expansion of consciousness". Also referred to as classic hallucinogens or serotonergic hallucinogens, the term ''psychedelic'' is sometimes used more broadly to include various other types of hallucinogens as well, such as those which are atypical or adjacent to psychedelia like salvia and MDMA, respectively. Classic psychedelics generally cause specific psychological, visual, and auditory changes, and oftentimes a substantially altered state of consciousness. They have had the largest influence on science and culture, and include mescaline, LSD, psilocybin, and DMT. There are a large number of both naturally occurring and synthetic serotonergic psychedelics. Most psychedelic drugs fall into one of the three families of chemical compounds: tryptamines, phenethylamines, or lysergamides. They produce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hallucinogen
Hallucinogens, also known as psychedelics, entheogens, or historically as psychotomimetics, are a large and diverse class of psychoactive drugs that can produce altered states of consciousness characterized by major alterations in thought, mood, and perception as well as other changes. Hallucinogens are often categorized as either being psychedelics, dissociatives, or deliriants, but not all hallucinogens fall into these three classes. Examples of hallucinogens include psychedelics or serotonin 5-HT2A receptor agonists like LSD, psilocybin, mescaline, and DMT; dissociatives or NMDA receptor antagonists like ketamine, PCP, DXM, and nitrous oxide; deliriants or antimuscarinics like scopolamine and diphenhydramine; cannabinoids or cannabinoid CB1 receptor agonists like THC, nabilone, and JWH-018; κ-opioid receptor agonists like salvinorin A and pentazocine; GABAA receptor agonists like muscimol and gaboxadol; and oneirogens like ibogaine and harmaline, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metacognitive Training
Metacognitive training (MCT) is an approach for treating the symptoms of psychosis in schizophrenia, especially delusions, which has been adapted for other disorders such as depression, obsessive–compulsive disorder and borderline over the years (see below). It was developed by Steffen Moritz and Todd Woodward. The intervention is based on the theoretical principles of cognitive behavioral therapy, but focuses in particular on problematic thinking styles (cognitive biases) that are associated with the development and maintenance of positive symptoms, e.g. overconfidence in errors and jumping to conclusions. Metacognitive training exists as a group training (MCT) and as an individualized intervention (MCT+). Background Metacognition can be defined as "thinking about thinking". Over the course of the training, cognitive biases subserving positive symptoms are identified and corrected. The current empirical evidence assumes a connection between certain cognitive biases, such as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antipsychotic
Antipsychotics, previously known as neuroleptics and major tranquilizers, are a class of Psychiatric medication, psychotropic medication primarily used to manage psychosis (including delusions, hallucinations, paranoia or disordered thought), principally in schizophrenia but also in a range of other psychotic disorders. They are also the mainstay, together with mood stabilizers, in the treatment of bipolar disorder. Moreover, they are also used as adjuncts in the treatment of Treatment-resistant depression, treatment-resistant major depressive disorder. The use of antipsychotics may result in many unwanted side effects such as Extrapyramidal symptoms, involuntary movement disorders, gynecomastia, impotence, weight gain and metabolic syndrome. Long-term use can produce List of long term side effects of antipsychotics, adverse effects such as tardive dyskinesia, tardive dystonia, Akathisia, tardive akathisia, and brain tissue volume reduction. The long term use of antipsychotics ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atypical Antipsychotic
The atypical antipsychotics (AAP), also known as second generation antipsychotics (SGAs) and serotonin–dopamine antagonists (SDAs), are a group of antipsychotic drugs (antipsychotic drugs in general are also known as tranquilizers and neuroleptics, although the latter is usually reserved for the '' typical antipsychotics'') largely introduced after the 1970s and used to treat psychiatric conditions. Some atypical antipsychotics have received regulatory approval (e.g. by the FDA of the US, the TGA of Australia, the MHRA of the UK) for schizophrenia, bipolar disorder, irritability in autism, and as an adjunct in major depressive disorder. Both generations of medication tend to block receptors in the brain's dopamine pathways. Atypicals are less likely than haloperidol—the most widely used typical antipsychotic—to cause extrapyramidal motor control disabilities in patients such as unsteady Parkinson's disease–type movements, body rigidity, and involuntary ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
