Hallucination

Extracted Attributes

• Types

  Hypnagogic (while falling asleep), Hypnopompic (while waking up), Multimodal (involving multiple senses)

• AI Context

  Inaccurate or nonsensical outputs from AI models

• Definition

  A perception in the absence of an external stimulus that has the compelling sense of reality.

• AI Challenge

  Significant obstacle to reliable deployment of AI

• Distinction from

  Dreaming, Pseudohallucination, Illusion, Mental imagery, Delusional perceptions

• Sensory Modalities

  Visual, Auditory, Olfactory, Gustatory, Tactile, Proprioceptive, Equilibrioceptive, Nociceptive, Thermoceptive, Chronoceptive

• Associated Conditions/Causes

  Drug use (deliriants, opioids), Sleep deprivation, Psychosis (including stress-related), Neurological disorders, Delirium tremens, Sleep paralysis, Schizophrenia, Mental illnesses, Side effects of medications, Epilepsy, Alcohol use disorder

• Auditory Hallucination Content

  55% malicious

• Associated Brain Regions (Auditory)

  Reduced grey matter in superior temporal gyrus/middle temporal gyrus (including Broca's area) as a trait; increased activity in same regions, hippocampus, parahippocampus, right hemispheric homologue of Broca's area for acute hallucinations.

Timeline

• Sir Thomas Browne introduced the word 'hallucination' into the English language, deriving it from the Latin 'alucinari' meaning 'to wander in the mind'. (Source: Wikipedia)

  1646-00-00

Hallucination

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 a disturbance, and can occur in most of the senses above. These may be things like seeing movement in peripheral vision, or hearing faint noises or voices. Auditory hallucinations are very common in schizophrenia. They may be benevolent (telling the subject good things about themselves) or malicious, cursing the subject. 55% of auditory hallucinations are malicious in content, for example, people talking about the subject, not speaking to them directly. Like auditory hallucinations, the source of the visual counterpart can also be behind the subject. This can produce a feeling of being looked or stared at, usually with malicious intent. Frequently, auditory hallucinations and their visual counterpart are experienced by the subject together. Hypnagogic hallucinations and hypnopompic hallucinations are considered normal phenomena. Hypnagogic hallucinations can occur as one is falling asleep and hypnopompic hallucinations occur when one is waking up. Hallucinations can be associated with drug use (particularly deliriants), sleep deprivation, psychosis (including stress-related psychosis), neurological disorders, and delirium tremens. Many hallucinations happen also during sleep paralysis. The word "hallucination" itself was introduced into the English language by the 17th-century physician Sir Thomas Browne in 1646 from the derivation of the Latin word alucinari meaning to wander in the mind. For Browne, hallucination means a sort of vision that is "depraved and receive[s] its objects erroneously".

Web Search Results

• Hallucination - Wikipedia

  A hallucination is a perception in the absence of an external stimulus "Stimulus (physiology)") 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 [...] Hallucinations are associated with structural and functional abnormalities in primary and secondary sensory cortices. Reduced grey matter in regions of the superior temporal gyrus/middle temporal gyrus, including Broca's area, is associated with auditory hallucinations as a trait, while acute hallucinations are associated with increased activity in the same regions along with the hippocampus, parahippocampus, and the right hemispheric homologue of Broca's area in the inferior frontal gyrus. [...] Hallucinations, pseudohallucinations, or intensification of pareidolia, particularly auditory, are known side effects of opioids to different degrees—it may be associated with the absolute degree of agonism or antagonism of especially the kappa opioid receptor, sigma receptors, delta opioid receptor and the NMDA receptors or the overall receptor activation profile as synthetic opioids like those of the pentazocine, levorphanol, fentanyl, pethidine, methadone and some other families are more

• Hallucinations: Causes, Types, Diagnosis, Treatment - WebMD

  Sometimes, a hallucination means you'll see something that isn't there. But hallucinations can affect any of your senses. (Photo Credit: E+/Getty Images) Hallucinations are false perceptions, where you sense an object, person, or event even though it is not really there or didn't happen. It seems very real to you. Sometimes, you may know you're having a hallucination. Other times, you may be sure it's real. [...] If you're like most folks, you probably think hallucinations always have to do with seeing things that aren't really there. But there's a lot more to it. It could mean you touch or even smell something that doesn't exist. Hallucinations can involve any one or all of your senses: sight, sound, smell, touch, and taste. [...] Hallucinations are false perceptions in which you'll think you're seeing, hearing, touching, or tasting something that isn't there. Many things can cause them, and they may be temporary or ongoing. If you or a loved one is having hallucinations, see a doctor to find out the cause and next steps. ## Hallucinations FAQs Can anxiety cause hallucinations?

• Hallucinations: Causes, Types & Treatment

  Hallucinations are complex phenomena that can be difficult to comprehend. They are essentially sensory experiences that appear real but are created by the mind. These experiences can occur in any sensory modality, including sight, sound, smell, taste, touch and even body position or movement. ### Definition of hallucination A hallucination is defined as a perception in the absence of an external stimulus that has qualities of real perception. [...] Image 2: A distressed woman sits on a sofa while her therapist, who sits across from her, takes note. Hallucinations can be a perplexing and often frightening experience. They are sensory perceptions that seem real but are created by the mind, occurring in the absence of an external stimulus. [...] In simpler terms, it’s experiencing something that isn’t there, but feels convincingly real to the person experiencing it. ### Delusion vs hallucinations It’s important to distinguish between hallucinations and delusions. While they may seem similar, they are fundamentally different. Delusions are false beliefs, while hallucinations are false sensory perceptions. In other words, delusions are about what you think, while hallucinations are about what you perceive.

• What Are Hallucinations and What Causes Them? - Healthline

  #### Mental Well-Being # What Are Hallucinations and What Causes Them? Hallucinations are sensory experiences that appear real but are created by your mind. They can affect all five of your senses. For example, you might hear a voice that no one else can hear or see an image that isn’t real. These symptoms may be caused by mental illnesses, the side effects of medications, or physical illnesses like epilepsy or alcohol use disorder. [...] Visual hallucinations involve seeing things that aren’t there. The hallucinations may be of objects, visual patterns, people, or lights. For example, you might see a person who’s not in the room or flashing lights that no one else can see. ### Olfactory hallucinations Olfactory hallucinations involve your sense of smell. You might smell an unpleasant odor when waking up in the middle of the night or feel that your body smells bad when it doesn’t.

• Hallucinations: MedlinePlus Medical Encyclopedia

  Hallucinations involve sensing things such as visions, sounds, or smells that seem real but are not. These things are created by the mind. Considerations Common hallucinations can include: Sometimes, hallucinations are normal. For example, hearing the voice of or briefly seeing a loved one who recently died can be a part of the grieving process. Causes There are many causes of hallucinations, including: When to Contact a Medical Professional

• Instance Of

  Q4167410

A hallucination is a perception in the absence of an external stimulus that has the qualities of a real perception. Hallucinations are vivid, substantial, and are perceived to be located in external objective space. Hallucination is a combination of 2 conscious states of brain wakefulness and REM sleep. 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. Many hallucinations happen also during sleep paralyses. 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 a disturbance, and can occur in most of the senses above. These may be things like seeing movement in peripheral vision, or hearing faint noises or voices. Auditory hallucinations are very common in schizophrenia. They may be benevolent (telling the subject good things about themselves) or malicious, cursing the subject. 55% of auditory hallucinations are malicious in content, for example, people talking about the subject, not speaking to them directly. Like auditory hallucinations, the source of the visual counterpart can also be behind the subject. This can produce a feeling of being looked or stared at, usually with malicious intent. Frequently, auditory hallucinations and their visual counterpart are experienced by the subject together. Hypnagogic hallucinations and hypnopompic hallucinations are considered normal phenomena. Hypnagogic hallucinations can occur as one is falling asleep and hypnopompic hallucinations occur when one is waking up. Hallucinations can be associated with drug use (particularly deliriants), sleep deprivation, psychosis, neurological disorders, and delirium tremens. The word "hallucination" itself was introduced into the English language by the 17th-century physician Sir Thomas Browne in 1646 from the derivation of the Latin word alucinari meaning to wander in the mind. For Browne, hallucination means a sort of vision that is "depraved and receive[s] its objects erroneously".