All articles starting with H
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Hallowell Davis
Hallowell Davis (1896–1992) was an American neurophysiologist who helped found clinical electroencephalography in the United States and became a leading figure in audiology and hearing conservation.
Hallows' Eve (Marvel Comics)
Hallows' Eve (Hallow's Eve), Marvel Comics Spider-Man character, real name Elizabeth Tyne/Janine Godbe, created by DeMatteis and Romita Jr. in 1995; became a mask-powered Dark Web villain in Amazing Spider-Man #14 (2022) and headlined a 2023 series by Erica Schultz.
Halloysite
Halloysite is a naturally occurring aluminosilicate clay mineral of the kaolin group that most commonly occurs as hollow nanoscale tubes rather than the flat plates of kaolinite.
Halls of Stone
"Halls of Stone" is the fifth episode of the second season of The Rings of Power, premiering on Prime Video on September 12, 2024, written by Nicholas Adams.
Hallstatt
Hallstatt, Austrian lakeside market town in the Salzkammergut, Upper Austria; site of the world's oldest known salt mine (c. 1500 BC), namesake of the Hallstatt culture, UNESCO World Heritage since 1997, and a major overtourism hotspot.
Hallstatt culture
Hallstatt culture: Early Iron Age archaeological culture of Central Europe, about 800–450 BC, named after the Hallstatt salt-mining site in Upper Austria; succeeded by the La Tène culture and known for organized salt mining, a 5,000-grave cemetery, and long-distance trade.
Hallstatt-Dachstein / Salzkammergut Cultural Landscape
Hallstatt-Dachstein / Salzkammergut Cultural Landscape, Austrian UNESCO World Heritage Site inscribed 1997 under criteria (iii) and (iv); 28,637 ha alpine region shaped by salt mining from the Bronze Age, giving its name to the Hallstatt culture.
Hallucigenia
Hallucigenia, genus Hallucigenia sparsa, a spiny Cambrian lobopodian worm from the Burgess Shale about 508 million years old, famously first reconstructed upside down and back to front, with its true head identified in 2015 and claw anatomy linking it to velvet worms.
Hallucination
Hallucination: a sensory perception without an external stimulus, in any modality. Also called voice hearing (auditory). Occurs in ~9.6% of the general population lifetime, 80% in schizophrenia; not pathognomonic of any disorder.
Hallucination (artificial intelligence)
AI hallucination is output from a generative model that looks fluent or plausible but lacks grounding in verifiable facts, ranging from minor inaccuracies to entirely fabricated content.
Hallucination in multimodal models
Hallucination in multimodal models is the generation of plausible but incorrect output, most often when vision-language models describe objects absent from an image, a major obstacle to reliable real-world use.
Hallucinogen
Hallucinogens are drugs that profoundly alter perception, mood, and thought, including classic psychedelics (LSD, psilocybin, DMT), dissociatives (ketamine, PCP), MDMA, and atypical agents like ibogaine, with history, effects, risks, and regulation.
Hallucinogen dependence
Hallucinogen dependence is a disorder of dysregulated hallucinogen use, marked by impaired control, use taking precedence over other pursuits, and persistence despite harm; ICD-11 classifies it under code 6C49.2.
Hallucinogen intoxication
Hallucinogen intoxication (ICD-11 6C49.3) is a transient condition during or shortly after hallucinogen use, with perceptual, cognitive, and autonomic disturbances; managed mainly with reassurance and benzodiazepines, with hyperthermia and tachydysrhythmias as key dangers.
Hallucinogen persisting perception disorder
Hallucinogen persisting perception disorder (HPPD), formerly post-hallucinogen perception disorder or flashback syndrome, is a DSM-5 disorder (292.89, F16.983) of persistent re-experienced perceptual disturbances after hallucinogen use, with intact reality testing, roughly 4% estimated prevalence, and antipsychotics worsening symptoms.
Hallucinogen-induced anxiety disorder
Hallucinogen-induced anxiety disorder (ICD-11 6C49.61) is a substance-induced anxiety disorder with symptoms during or soon after hallucinogen intoxication, exceeding intoxication-level anxiety and not better explained by a primary disorder.
Hallucinogen-induced mood disorder
Hallucinogen-induced mood disorder (ICD-11 6C49.60) is mood disturbance, depressive, manic, or mixed, arising during or soon after hallucinogen intoxication, distinguished from primary mood disorders by resolution after cessation of use.
Hallucinogen-induced psychotic disorder
Hallucinogen-induced psychotic disorder (ICD-11 6C49.5): psychotic symptoms such as delusions and hallucinations arising during or soon after hallucinogen intoxication, with 26% pooled transition to schizophrenia.
Hallucinogenic bolete mushroom
Hallucinogenic bolete mushrooms, chiefly Lanmaoa asiatica of Yunnan and Boletus manicus of Papua New Guinea, cause hallucinations of little people when undercooked, with no identified psychedelic compound.
Hallucinogenic fish
Hallucinogenic fish, or ichthyoallyeinotoxism, is rare fish poisoning from species like Sarpa salpa (dreamfish, salema porgy), Siganus spinus, and Kyphosus, causing vivid hallucinations, nightmares, and delirium within minutes to 2 hours, lasting up to 24 hours.
Hallucinogenic snuff
Hallucinogenic snuff (yopo, cohoba, paricá) is a powdered tryptamine preparation inhaled nasally, made from Anadenanthera peregrina seeds rich in bufotenine; used ritually in South America and the pre-Columbian Caribbean for millennia.
Hallushu-Inshushinak
Hallushu-Inshushinak (Ḫallušu-Inšušinak), also known as Hallushu, was king of Elam from about 699 to 693 BC, succeeding his older brother Shutruk-Nahhunte II during the wars with Assyria.
Hallutash-Inshushinak
Hallutash-Inshushinak (Ḫallutuš-Inšušinak) was a king of Elam of the Middle Elamite period, ruling in the decades around 1200 BC and remembered as the father of Shutruk-Nahhunte I, founder of the Shutrukid dynasty.
Hallux rigidus
Hallux rigidus is osteoarthritis of the joint at the base of the great toe, causing pain, stiffness, and limited upward bending; it mainly develops after age 40.
Hallux valgus surgery
Hallux valgus surgery is a set of orthopedic procedures that realign a deviated big toe, or bunion, by cutting and repositioning bone, balancing soft tissue, or fusing a joint.
HallyuPopFest
HallyuPopFest is a K-pop music festival first held in September 2018 at the Singapore Indoor Stadium, featuring 111 idols from 21 acts, and expanded to London and Sydney in 2022.
Halma
Halma is an 1883 American race board game by surgeon George Howard Monks, played on a 16x16 square board with 19 pieces moving by steps and non-capturing jump chains into the opposite camp; its 1892 German star-board adaptation became Chinese Checkers.
Halmahera Island
Halmahera, largest island of Indonesia's Moluccas (Spice Islands) in North Maluku, a K-shaped volcanic island of about 18,000 km2 in Wallacea, home to Mount Dukono and exceptional endemism.
Halmahera Sea
Halmahera Sea: quasi-confined marginal sea in eastern Indonesia between Halmahera Island and Irian Jaya, a secondary entry portal of the Indonesian Throughflow, with ENSO-linked variability, intense internal-wave mixing, and Coral Triangle coral biodiversity.
Halo (Beyoncé song)
Halo is a 2009 pop-R&B power ballad by Beyoncé from I Am... Sasha Fierce, written with Ryan Tedder and Evan Bogart, released January 20, 2009 on Columbia; US Hot 100 No. 5, UK No. 4, 2010 Grammy winner.