1,240 articles
Neutron capture therapy of cancer
Neutron capture therapy of cancer (BNCT): radiation therapy injecting boron-10 drugs that collect in tumors, then irradiating with neutrons; 10B(n,alpha)7Li reaction, Hatanaka's 58% 5-year GBM survival, Japan 2020 insurance approval.
NIfTI
NIfTI (Neuroimaging Informatics Technology Initiative) is a file format for storing neuroimaging data, developed by a National Institutes of Health working group in the early 2000s.
Night vision
Night vision: low-light seeing mediated by rod photoreceptors and rhodopsin, restored through slow dark adaptation and the RPE visual cycle; vitamin A deficiency, Oguchi disease, and AMD delay it.
Nightmare
Nightmare: an extended, extremely dysphoric dream, usually in REM sleep; nightmare disorder affects 3.5-8.3% of adults. Treated with imagery rehearsal therapy and prazosin.
Nigrostriatal pathway
Nigrostriatal pathway: dopaminergic tract from the substantia nigra pars compacta (A9) to the dorsal striatum (caudate and putamen), governing motor control and associative learning; its degeneration causes Parkinson's disease, and it also contributes to reward.
Nobel Prize in Physiology or Medicine for neuroscience research
Nobel Prizes in Physiology or Medicine have honored neuroscience since 1906, when Golgi and Cajal shared the first, through at least 17 prizes and 40 laureates to 2021.
Nociceptor
A nociceptor, also called a pain receptor, is a sensory neuron that responds to noxious, tissue-damaging stimuli, triggering pain signals in the spinal cord and brain.
Noise-induced hearing loss
Noise-induced hearing loss (NIHL) is permanent or temporary hearing loss from loud impulse sounds or repeated exposure above 85 dBA, damaging cochlear hair cells; preventable, common in workers and teens, with no cure.
Non-invasive and partially invasive brain–computer interfaces
Non-invasive and partially invasive brain–computer interfaces (BCIs) record brain activity without penetrating brain tissue, using scalp EEG or electrodes placed under the skull, as in ECoG and endovascular Stentrode implants.
Non-rapid eye movement sleep
Non-rapid eye movement (NREM) sleep, stages N1–N3, is the non-dream-exclusive phase of sleep marked by slow waves and spindles, deep slow-wave sleep, memory consolidation, and cycles alternating with REM every 80–100 minutes.
Non-spiking neuron
Non-spiking neuron: a neuron signaling with graded, analog membrane potentials instead of action potentials, as in retinal rods, cones, horizontal and bipolar cells, and many invertebrate interneurons; graded synapses release transmitter continuously with ribbon zones and L-type Ca2+ channels.
Nonproliferative diabetic retinopathy
Nonproliferative diabetic retinopathy (NPDR) is the early stage of diabetic retinopathy, marked by microaneurysms, hemorrhages, exudates, IRMA, and venous beading without neovascularization, staged mild, moderate, or severe.
Nonsynaptic plasticity
Nonsynaptic plasticity: activity- or learning-induced changes in neuronal intrinsic excitability, ion channels, myelin, and homeostatic or metaplastic mechanisms, rather than synaptic strength; includes intrinsic plasticity, slow AHP reductions, and transient excitability-based memory traces.
Noradrenergic neuron
A noradrenergic neuron is a neuron that synthesizes and releases norepinephrine (noradrenaline), a neurotransmitter governing arousal, attention, and stress; the largest cluster sits in the brainstem's locus coeruleus.
NR082 (NFS-01, ND4 AAV gene therapy)
NR082 (NFS-01, esonadogene imvoparvovec) is Neurophth's rAAV2-ND4 intravitreal gene therapy for ND4-mutation Leber hereditary optic neuropathy, first trialed in Wuhan in 2011 and in phase 3 GOLD and sham-controlled trials.
Nuclear Events (kinase and transcription factor activation)
Nuclear Events (kinase and transcription factor activation), Reactome pathway R-HSA-198725: human neurotrophin/NTRK1 signaling in which MAPK-family kinases phosphorylate nuclear transcription factors such as CREB1 and ELK1, inducing immediate-early and delayed-early genes.
Nucleus accumbens
Nucleus accumbens (NAc, NAcc), ventral striatum region with core, shell, and rostral pole subdivisions; GABAergic MSNs receiving VTA dopamine and prefrontal glutamate; central to reward, motivation, addiction relapse, and DBS targets.
NUZ-001 (monepantel)
NUZ-001 is the clinical code for (S)-monepantel, a veterinary anthelmintic repurposed by Neurizon Therapeutics as an investigational amyotrophic lateral sclerosis drug, now in Phase 2/3 testing.
Nystagmus
Nystagmus: involuntary rhythmic eye movement with slow and fast phases, classified as infantile (congenital) or acquired. Causes include albinism, FRMD7 mutation, retinal disease, and brainstem or cerebellar lesions.
Obstruction of Eustachian tube
Obstruction of the Eustachian tube (ICD-10 H68.1), obstructive or dilatory Eustachian tube dysfunction: failure of tubal opening causing middle-ear pressure dysregulation; treated medically or by balloon dilation with about 1.4% complication rate.
Occipital lobe
Occipital lobe: smallest, rearmost cerebral lobe, housing the primary visual cortex (V1, calcarine sulcus) and dorsal/ventral visual streams; supplied by the posterior cerebral artery; damage causes homonymous field loss and cortical blindness.
Ocular dominance
Ocular dominance: behavioral preference for one eye and its cortical counterpart, ocular dominance columns in V1, described by Hubel and Wiesel; covers critical-period plasticity, deprivation, amblyopia, and the unsupported link to reading skill.
Ocular motor nerve palsies
Ocular motor nerve palsies are deficits of cranial nerves III, IV, and VI causing diplopia. Also called third, fourth, sixth nerve palsy. Causes include microvascular ischemia, inflammation, aneurysm, tumor; pupil-involving third palsy is an emergency.
Ocular surface squamous neoplasia
Ocular surface squamous neoplasia (OSSN), also called conjunctival intraepithelial neoplasia spectrum, is a dysplasia-to-invasive-squamous-cell-carcinoma continuum of the conjunctiva and cornea, linked to UVB, HPV, and HIV, treated by excision or topical interferon, 5-FU, or mitomycin C.
Oculomotor nerve
Oculomotor nerve (cranial nerve III): midbrain motor nerve supplying four extraocular muscles, levator palpebrae, and pupil constriction via Edinger-Westphal fibers; palsy causes ptosis, diplopia, down-and-out eye, pupil-involving from aneurysm or herniation.
Oculomotor nerve palsy
Oculomotor nerve palsy (third cranial nerve palsy, CN III palsy) causes ptosis, diplopia, and a down-and-out eye; pupil involvement signals aneurysm and urgent imaging, while pupil sparing suggests microvascular ischemia.
Olfactory bulb
Olfactory bulb: first central processing station for smell in the forebrain, receiving olfactory nerve input in glomeruli (100-200 um) and relaying via mitral and tufted cells to piriform cortex; site of adult neurogenesis and a marker in neurodegenerative disease.
Olfactory nerve
The olfactory nerve, or CN I, is the first cranial nerve, carrying smell signals from the roof of the nasal cavity to the olfactory bulbs of the brain.
Olfactory receptor cell
Olfactory receptor cell, also called olfactory receptor neuron or olfactory sensory neuron: bipolar neuron in the nasal olfactory epithelium that detects odorants via GPCR-cAMP transduction in its cilia and sends unmyelinated axons to the olfactory bulb; each expresses one odorant receptor and turns over throughout life.
Oligodendrocyte
Oligodendrocyte, also called oligodendroglia: CNS glial cell forming myelin sheaths around multiple axons (up to 1–40), unlike single-axon Schwann cells; arises from OPCs, supports axons metabolically, and enables remyelination in multiple sclerosis.