1,240 articles
NAION trial
Clinical trials for non-arteritic anterior ischemic optic neuropathy (NAION): the IONDT surgical trial and small citicoline (CDP-choline) studies; no treatment has demonstrated proven efficacy.
Nap
Nap: a short period of daytime sleep, also called a siesta. Key facts: short naps restore alertness and cognition; waking from slow-wave sleep causes sleep inertia; naps over 30-60 minutes are linked to worse cardiovascular and mortality outcomes.
NCE-G 120
NCE-G 120 (G120, NeuroChirurgie Eppendorf-Glioma 120), CVCL_N742, is a human glioblastoma cancer cell line from a 59-year-old male, left temporo-parietal junction, used in p53, radiation, and transcriptomic studies.
NCE-G 44
NCE-G 44 (G44, GL44; CVCL_N727) is a human glioblastoma cell line from a 64-year-old woman's left parietal lobe, established at University Hospital Hamburg-Eppendorf, with a TP53 p.Glu224Ter mutation and high MGMT-driven temozolomide resistance.
Near-sightedness
Near-sightedness (myopia) is a refractive error in which light focuses in front of the retina, blurring distance vision. Onset is typically ages 6–14; atropine drops, multifocal lenses, and orthokeratology slow childhood progression.
Neck
The neck (cervical spine): seven vertebrae C1–C7, atlas and axis, eight cervical nerves, discs and facet joints, supporting the head, enabling motion, and protecting the spinal cord.
Neil Harbisson
Neil Harbisson is a British-born artist and cyborg activist born with achromatopsia. His antenna implant converts light frequencies into sound, enabling him to hear colors beyond the human spectrum.
Neocortex
Neocortex (isocortex): the six-layered outer cerebral cortex found only in mammals, part of the dorsal pallium, up to about 80% of the human brain, expanded in human prefrontal and language areas.
Nerve block
Nerve block: injection of medication near a nerve or nerve group for pain relief, diagnosis, or surgical anesthesia. Also regional anesthesia; first performed by Halsted with cocaine in 1884; includes epidural, Bier, and peripheral blocks.
Nerve compression syndrome
Nerve compression syndrome, or entrapment neuropathy, is pressure on a peripheral nerve at anatomical tunnels, causing pain, numbness, and weakness. Carpal tunnel syndrome is the most common type; cubital tunnel is second.
Nerve conduction study
Nerve conduction study (NCS), also called nerve conduction velocity test, is an electrodiagnostic test stimulating peripheral nerves to measure latency, amplitude, and conduction velocity, used with EMG to diagnose neuropathy and compression syndromes like carpal tunnel.
Nerve conduction velocity
Nerve conduction velocity (NCV), also called a nerve conduction study (NCS), measures how fast electrical signals travel along peripheral nerves using surface electrodes. Covers Helmholtz's 1870 measurement, temperature and age effects, diagnostic thresholds, and AANEM standards.
Nerve growth factor
Nerve growth factor (NGF), the first discovered neurotrophin, found by Levi-Montalcini and Hamburger in the 1950s; signals via TrkA and p75NTR; basis for cenegermin (neurotrophic keratitis) and anti-NGF pain drugs.
Nervous tissue
Nervous tissue, also called neural tissue, is the excitable tissue of the nervous system composed of neurons and glial cells (neuroglia), with six glial types across CNS and PNS, myelin from oligodendrocytes and Schwann cells, and the neuron doctrine of Cajal and Golgi as its foundation.
Netrin
Netrins (from Sanskrit 'Netr', guide) are laminin-related extracellular guidance proteins, including secreted netrin-1, 3, 4 and GPI-anchored netrin G1/G2, that attract or repel migrating axons via DCC and UNC5 receptors and also act in cancer.
Network dynamics of conscious states
Network dynamics of conscious states is the study of how brain integration and segregation change across sleep, waking, and anesthesia, measured by tools like the perturbational complexity index.
Neural computation
Neural Computation (Neural Comput.), MIT Press journal founded 1989 by Terrence Sejnowski; monthly peer-reviewed venue for theory, modeling, and statistics in neuroscience and neurally inspired AI systems.
Neural correlates of consciousness
Neural correlates of consciousness (NCC): the minimal neural mechanisms jointly sufficient for a conscious percept, defined by Crick and Koch (1990); research centers on the posterior cortical hot zone versus fronto-parietal theories, tested by adversarial collaborations and anesthesia studies.
Neural development
Neural development, also called neurodevelopment, is the process by which the nervous system forms, from the embryonic neural plate and tube through neurogenesis, migration, synaptogenesis, and lifelong synaptic pruning.
Neural plate
Neural plate: thickened columnar ectoderm induced by notochord signals during neurulation; folds into the neural tube (brain and spinal cord precursor). BMP antagonism induces it; failure of closure causes neural tube defects like spina bifida.
Neural progenitor cell
A neural progenitor cell is an undifferentiated cell derived from a neural stem cell with limited self-renewal, central to embryonic brain development and under study in clinical transplantation.
Neural stem cell
A neural stem cell (NSC) is a self-renewing, multipotent cell that generates the neurons and glia of the nervous system, persisting into adulthood in mammals.
Neural tube
Neural tube: embryonic epithelium with a central lumen that forms the vertebrate brain and spinal cord during neurulation (weeks 3-4 in humans); closure failure causes neural tube defects preventable by folic acid.
Neural–electrode interface and biocompatibility
The neural–electrode interface is where an implanted electrode meets living neural tissue; immune reactions and scar tissue raise impedance and kill recording sites, making it the bottleneck for devices like Utah arrays and DBS leads.
Neuralink
Neuralink: neurotechnology company co-founded by Elon Musk (2016) making the N1 invasive brain-computer implant (1,024 electrodes, 64 threads, R1 robot insertion) for paralysis; 12 patients implanted by 2025, FDA breakthrough designations for Blindsight and speech.
Neurapraxia
Neurapraxia is the mildest peripheral nerve injury, a temporary conduction block from focal demyelination with the axon intact, per Seddon's 1942 classification; it recovers spontaneously within weeks to about three months.
Neurite orientation dispersion and density imaging
Neurite orientation dispersion and density imaging (NODDI) is a diffusion MRI technique introduced by University College London researchers in 2012 that estimates the density and angular spread of dendrites and axons in the living human brain.
Neuroblast (sensu Nematoda and Protostomia)
Neuroblast (sensu Nematoda and Protostomia), Cell Ontology term CL:0000338, is the invertebrate CNS neural precursor, a self-renewing stem cell dividing asymmetrically into ganglion mother cells, distinct from the postmitotic vertebrate neuroblast.
Neurochemistry
Neurochemistry: study of the chemistry of the brain and nerves, from Hensing's 1719 phosphorus treatise and French quantitative analyses to neurotransmitters, dopamine, ISN, JNC, and in vivo microdialysis methods.
Neurofeedback
Neurofeedback (EEG biofeedback, neurotherapy): real-time feedback of brain activity to train self-regulation, founded on Kamiya's 1960s alpha work and Sterman's SMR epilepsy research; ADHD meta-analyses find no stand-alone benefit.