864 articles
Helsmoortel-Van der Aa syndrome
Helsmoortel-Van der Aa syndrome (HVDAS, ADNP syndrome, OMIM 615873) is a rare autosomal dominant neurodevelopmental disorder caused by de novo loss-of-function ADNP variants, featuring intellectual disability, autism, hypotonia, dysmorphic facies, and multi-organ problems.
Hick's law
Hick's law, or the Hick–Hyman law, states that choice reaction time rises linearly with the logarithm of the number of alternatives (RT = a + b log2 n). Established by W. E. Hick (1952) and Ray Hyman (1953) from information theory, with roots in Merkel's 1885 experiments; a foundational but debated principle of interface design.
HIDEA syndrome
HIDEA syndrome is a rare autosomal recessive neurodevelopmental disorder caused by P4HTM gene variants, first described in 2014 in Finland; fewer than 50 patients worldwide show hypotonia, intellectual disability, and epilepsy.
History of mood disorders
The history of mood disorders covers how Western medicine explained and treated disordered mood, from ancient humoral melancholia to the operational categories of DSM-III in 1980.
History of psychiatry
History of psychiatry: from ancient accounts of madness through asylums, Pinel and Tuke's moral treatment, the DSM's growth from 128 to 541 categories, deinstitutionalization, and the 1990 journal History of Psychiatry.
Histrionic personality disorder
Histrionic personality disorder, formerly hysterical personality disorder, is a cluster B psychiatric condition marked by persistent attention-seeking, exaggerated emotions, and theatrical, self-dramatized behavior beginning by early adulthood.
Hogeweyk
De Hogeweyk, the original dementia village in Weesp, Netherlands, opened 2009: a gated nursing home where ~152 people with severe dementia live in lifestyle-matched shared houses with shops, pub, and theater; antipsychotic use reportedly fell to ~12%.
Holding space
Holding space: supportive practice of non-judgmental, present listening without fixing or judging, rooted in Winnicott's holding environment and popularized by Heather Plett's 2015 blog; used in therapy, coaching, and care.
Hospital Anxiety and Depression Scale
The Hospital Anxiety and Depression Scale (HADS) is a 14-item self-report questionnaire screening for anxiety and depression in medically ill patients, introduced by Zigmond and Snaith in 1983.
Houge-Janssens syndrome
Houge-Janssens syndrome (HJS, Jordan's syndrome for type 1) is a spectrum of rare autosomal dominant PP2A-related neurodevelopmental disorders (types 1-4, genes PPP2R5D, PPP2R1A, PPP2CA, PPP2R5C) marked by developmental delay, hypotonia, seizures, and macrocephaly or microcephaly.
Howard Dully
Howard Dully, American bus driver and author, lobotomized at age 12 in 1960 by Dr. Walter Freeman; told his story in the 2005 NPR documentary and 2007 memoir My Lobotomy.
Hyper-empathy
Hyper-empathy (hyperempathy) is above-average, overwhelming empathy, not a DSM-5 diagnosis; described mainly by autistic people and framed by Smith's empathy imbalance hypothesis of high affective with low cognitive empathy.
Hypergraphia
Hypergraphia: compulsive, extensive writing, classically an interictal feature of temporal lobe epilepsy (Geschwind syndrome, with hyperreligiosity and hyposexuality); also seen in mania and right temporal lobe degeneration.
Hyperlexia
Hyperlexia: precocious, self-taught word reading far exceeding comprehension, usually with autism (about 84% of cases); coined by Silberberg and Silberberg in 1967; not a standalone DSM-5 diagnosis; three described types.
Hypersexuality
Hypersexuality, also called compulsive sexual behavior disorder (ICD-11) or sex addiction, is abnormally extreme, poorly controlled sexual activity; often iatrogenic from dopaminergic drugs in Parkinson's disease, treated first with psychotherapy.
Hypervigilance
Hypervigilance: a heightened, continuous scanning of the environment for danger, a symptom rather than a diagnosis. Seen in PTSD, anxiety, trauma, and physical conditions; distinct from paranoia, managed with therapy, grounding, and mindfulness.
Hypnagogia
Hypnagogia is the transitional consciousness state at sleep onset (N1), marked by hypnagogic hallucinations; terms from Maury (1848), Myers (hypnopompic), Mavromatis (1983); common in the general population and narcolepsy, and studied for creativity via MIT's Dormio dream incubation.
Hypnosis
Hypnosis, also known as hypnotism, is a state of concentrated attention with reduced awareness of surroundings and heightened responsiveness to suggestion, first named in 1843.
Hypnotherapy
Hypnotherapy is the therapeutic use of hypnosis via induction and suggestion. Rooted in Mesmerism, named by Braid in 1843; best evidence for gut-directed IBS treatment, weaker for smoking cessation.
Hypoactive sexual desire disorder
Hypoactive sexual desire disorder (HSDD), also called female sexual interest/arousal disorder in DSM-5, is persistent low sexual desire causing marked distress. Covers diagnosis, prevalence (8–10% of women), mechanisms, flibanserin, bremelanotide, testosterone, and controversy.
Hypochondriasis
Hypochondriasis: persistent preoccupation with having serious illness despite reassurance; DSM-IV somatoform diagnosis, split by DSM-5 into illness anxiety disorder and somatic symptom disorder, retained in ICD-11.
Hypomania
Hypomania: a mild manic-type mood episode (elevated, expansive, or irritable mood plus increased energy, at least 4 days, no marked impairment, hospitalization, or psychosis) defining bipolar II disorder; term coined by Erich Mendel in 1881.
I'm OK – You're OK
I'm OK – You're OK (1969) is Thomas A. Harris's best-selling guide to Eric Berne's transactional analysis, presenting Parent-Adult-Child ego states and four life positions; it sold over 15 million copies and topped the New York Times non-fiction list in 1972.
ICD-11 classification of personality disorders
ICD-11 personality disorder classification (WHO, effective 2022): single dimensional diagnosis 6D10 rated mild, moderate, or severe, five trait domains (negative affectivity, detachment, dissociality, disinhibition, anankastia), optional borderline pattern specifier, replacing ICD-10's ten categorical diagnoses.
Identity disturbance
Identity disturbance: markedly and persistently unstable self-image or sense of self, a DSM-5 criterion of borderline personality disorder, rooted in Erikson's identity diffusion and Kernberg's identity diffusion construct, central to ICD-11 personality pathology severity.
Idiopathic catatonia
Idiopathic catatonia, also called isolated catatonia or idiopathic catatonic syndrome, is a rare condition marked by catatonic features without any psychiatric, medical, or substance cause.
Imagery rescripting
Imagery rescripting (ImRs) is a psychotherapy technique in which a patient recalls a distressing mental image, usually a memory, and imaginatively changes it with corrective information.
Imaginal exposure
Imaginal exposure is a psychotherapy technique in which a client repeatedly and vividly imagines a feared situation or trauma memory until anxiety and avoidance decline.
Imaginary friend
An imaginary friend, in developmental psychology an imaginary companion (IC), is a fictitious person, animal, or object created by a child, considered common healthy pretend play rather than a sign of disturbance.
Inappropriate affect
Inappropriate affect: emotional expression mismatching a person's experience, speech, or situation, e.g., laughing while describing a death. A Bleulerian cardinal symptom of schizophrenia, also seen in mania; now classed as disorganization, not blunted affect.