864 articles
Narcotics Anonymous
Narcotics Anonymous (NA), founded July 1953, is a free global twelve-step fellowship for recovering drug addicts with no drug distinctions, over 79,000 weekly meetings in 122 countries, governed by Twelve Traditions and NAWS in Chatsworth, California.
Narrative exposure therapy
Narrative exposure therapy (NET) is a short-term trauma-focused psychotherapy for PTSD, developed at the University of Konstanz, in which patients narrate their whole life story.
Narrative therapy
Narrative therapy is a psychotherapy approach developed by Michael White and David Epston that externalizes problems as separate from the person and helps people re-author their life stories.
National Institute of Mental Health
National Institute of Mental Health: the US NIMH (NIH, founded 1949, lead federal mental disorders research agency) and Japan's NIMH (国立精神衛生研究所, founded 1952, now part of NCNP), which was modeled on the American institute.
National Institute of Mental Health and Neurosciences
NIMHANS, Bengaluru, India's apex mental health and neurosciences institute, formed 1974 from the Mysore Government Mental Hospital and AIIMH; deemed university 1994, Institute of National Importance 2012; NIMHANS-2 announced 2026.
Negative affectivity
Negative affectivity, also called negative emotionality or neuroticism, is the trait tendency to experience distressing emotions like anxiety, anger, and depression; an ICD-11 personality trait domain (6D11.0) and DSM-5 AMPD domain.
Negativism
Negativism: a psychopathological sign of apparently motiveless resistance to instructions or examination, first described by Kahlbaum in 1874 as motor negativism in catatonia; also seen in autism, intellectual disability, and brain injury.
Neil J. Elgee
Neil J. Elgee (1926–2020) was an American physician who practiced internal medicine and endocrinology, taught at the University of Washington, and founded the Ernest Becker Foundation in 1993.
Neophobia
Neophobia is fear or avoidance of novel stimuli; food neophobia is reluctance to try unfamiliar foods, measured by the Pliner and Hobden Food Neophobia Scale, peaking at ages 2 to 6 and linked to poorer diet quality.
Neurasthenia
Neurasthenia, or nervous exhaustion (shenjing shuairuo, 神经衰弱), is a historical diagnosis introduced by George Beard in 1869, attributing fatigue and varied symptoms to depleted nervous energy; it peaked around 1900 and survives in ICD-10.
Neurodevelopmental disorder-craniofacial dysmorphism-cardiac defect-skeletal anomalies syndrome
Neurodevelopmental disorder-craniofacial dysmorphism-cardiac defect-skeletal anomalies syndrome, better known as Au-Kline syndrome, is a rare genetic disorder caused by HNRNPK variants, marked by developmental delay, intellectual disability, and heart defects.
Neurodevelopmental disorder-spasticity-movement disorder-epileptic syndrome
Neurodevelopmental disorder-spasticity-movement disorder-epileptic syndrome, or Kaya-Barakat-Masson syndrome (KABAMAS), is a rare autosomal recessive YIF1B-related disorder with severe developmental delay, spasticity, dystonia, seizures, and microcephaly; no approved treatments exist.
Neurofibrillary tangle
Neurofibrillary tangles: intracellular aggregates of hyperphosphorylated tau in paired helical filaments, defining lesions of Alzheimer's disease, staged by the Braak system, tracked by tau PET and MTBR-tau243, and targeted by etalanetug.
Neurosis
Neurosis: historical psychiatric term for anxiety-based disorders with intact reality testing, coined by Cullen in the 1780s, central to Freud, removed from DSM-III (1980); not a current DSM-5-TR or ICD-11 diagnosis.
Nicotine dependence
Nicotine dependence, also called tobacco use disorder, is a chronic relapsing disorder of nicotine regulation involving craving, tolerance, and withdrawal, driven by nicotinic acetylcholine receptor effects on dopamine circuits, and treated with NRT, varenicline, bupropion, or cytisine.
Nicotine withdrawal
Nicotine withdrawal: physical and psychological symptoms (cravings, irritability, insomnia, poor concentration) after stopping nicotine; begins 4-24 hours after last dose, peaks days 2-3, fades within 3-4 weeks; treated with NRT, varenicline, cytisine, bupropion, e-cigarettes, and counseling.
Nightmare disorder
Nightmare disorder, a DSM-5 and ICSD-3 REM sleep parasomnia, involves recurrent distressing nightmares causing impairment. Treated with imagery rehearsal therapy and prazosin; often drug-induced or PTSD-associated.
Nihilistic delusion
A nihilistic delusion is the belief that one's self, part of the body, or the whole world no longer exists, ranging from lost organs to believing one is already dead.
No Nut November
No Nut November (NNN) is an annual internet challenge, coined on Urban Dictionary in 2011 by bicboi6969696969, in which participants abstain from masturbation and ejaculation for November; it went viral in 2017 and has contested health claims.
NoFap
NoFap, also known as Nofap.com, is an online peer support community founded on Reddit in 2011 around abstaining from pornography for set periods such as the 90-day reboot.
Nomophobia
Nomophobia (no-mobile-phone phobia) is anxiety at being unable to use or access one's mobile phone; unrecognized in DSM-5/ICD-11, measured mainly by the 20-item NMP-Q, with pooled symptom prevalence of 94%.
Non-specific syndromic intellectual disability
Non-specific syndromic intellectual disability, also called complex neurodevelopmental disorder, is a rare genetic condition in which intellectual disability occurs alongside varied anomalies that do not form a defined syndrome.
Obsessive–compulsive disorder
Obsessive–compulsive disorder (OCD), a mental disorder of recurring obsessions and compulsions, lifetime prevalence 1–3%, classified in Obsessive-Compulsive and Related Disorders in DSM-5 and ICD-11, treated with ERP and SSRIs.
Obsessive–compulsive personality disorder
Obsessive–compulsive personality disorder (OCPD), also called anankastic personality disorder, is a Cluster C personality disorder marked by perfectionism, orderliness, and control; distinct from OCD, prevalence about 2–8%, treated with psychotherapy and SRIs.
Okur-Chung neurodevelopmental syndrome
Okur-Chung neurodevelopmental syndrome (OCNDS, OMIM 617062) is an ultra-rare autosomal dominant disorder caused by CSNK2A1 variants encoding CK2α, discovered in 2016 by Okur and Chung, causing developmental delay, hypotonia, language deficits, and sometimes seizures.
Olfactory reference disorder
Olfactory reference disorder (ORD, formerly olfactory reference syndrome, jikoshu-kyofu) is a psychiatric condition involving persistent false belief of emitting a foul body odor; ICD-11 code 6B22, treated with SRIs, antipsychotics, and CBT.
Open Dialogue
Open Dialogue is a psychosocial approach to psychosis and mental health crises, developed in Finnish Lapland, that treats patients in meetings with family and social network.
Ophidiophobia
Ophidiophobia, also called ophiophobia, is the specific phobia of snakes, an anxiety disorder affecting 2–3% of people; treated mainly with exposure therapy and studied through preparedness and snake detection theories.
Opiate Substitution Treatment
Opiate substitution treatment, also called opioid agonist maintenance treatment (OAMT), is long-term methadone or buprenorphine treatment for opioid dependence; methadone retains patients better, both cut mortality sharply.
Opioid epidemic
Opioid epidemic: the US overdose crisis since the mid-1990s, in three waves (prescription opioids from 1999, heroin from 2010, illegally made fentanyl from 2013), causing roughly 806,000 opioid overdose deaths from 1999 to 2023, with deaths declining since 2023.