bionics: …a semiconductor device called a neuristor was devised, capable of propagating a signal in one direction without attenuation and able to perform numerical and logical operations. The neuristor computer, inspired by a natural model, imitates the dynamic behaviour of natural neural information networks; each circuit can serve sequentially for different…

Alzheimer disease: Neuritic plaques and neurofibrillary tangles: The presence of neuritic plaques and neurofibrillary tangles in the brain are used to diagnose Alzheimer disease in autopsy. Neuritic plaques—also called senile, dendritic, or amyloid plaques—consist of deteriorating neuronal material surrounding deposits of a sticky protein called amyloid beta

neuritis, inflammation of one or more nerves. Neuritis can be caused by injury, infection, or autoimmune disease. The characteristic symptoms include pain and tenderness, impaired sensation, often with numbness or hypersensitivity, impaired strength and reflexes, and abnormal circulation and

fuzzy logic: Nonengineering applications: So-called neuro-fuzzy systems integrate fuzzy logic and artificial neural networks, enabling a certain form of learning. Systems with neuro-fuzzy components may be found in fields such as stock market prediction, intelligent information systems, and data mining (see database).

defense mechanism: …in Sigmund Freud’s paper “The Neuro-Psychoses of Defence” (1894).

hypothalamus: Hypothalamic regulation of hormone secretion: …an important group is the neuropeptides. The neuropeptides function not only as neurotransmitters but also as neuromodulators. As neuromodulators, they do not act directly as neurotransmitters but rather increase or decrease the action of neurotransmitters. Well-known examples are the opioids (e.g., enkephalins), so named because they are endogenous (produced in…

neurofeedback, form of therapy in which the brain’s electrical activity is assessed and measured to help correct dysfunctional or abnormal brain-wave patterns. Techniques used to detect electrical rhythms in the brain include electroencephalography (EEG), functional magnetic resonance imaging

emotion: The neurobiology of emotion: Before the advent of behaviourism, when the science of neurology was still in its infancy, the American philosopher and psychologist William James (1842–1910) brought some of the factors together in his theory of emotion, which he set out in his foundational study…

human nervous system: Morphological development: …cells differentiate and proliferate into neuroblasts, which are the precursors of neurons, and glioblasts, from which neuroglia develop. With a few exceptions, the neuroblasts, glioblasts, and their derived cells do not divide and multiply once they have migrated from the ventricular zone into the gray and white matter of the…

neuroblastoma, a tumour of the sympathetic nervous system (the branch of the autonomic nervous system that is best known for producing the fight-or-flight response) that affects young children. It is the most-common pediatric solid tumour that occurs outside the brain, with an annual incidence of

dystonia: , Botox™, Myobloc™, and NeuroBloc™). An injection of this potent blocker of nerve transmission produces a temporary chemical denervation of the muscles that may last for several months.

Heinrich Klüver: …later years Klüver turned to neurochemistry, particularly to the study of free porphyrins found in the brain. His work on the staining of nervous tissue was widely used by other investigators. He also wrote Mescal and Mechanisms of Hallucinations (1966).

annelid: Nervous system: …has giant nerve fibres (neurochords), which may have either a simple or a compound structure. Simple neurochords are very large single nerve cells; their axons arise from cells situated in either the brain or a segmental ganglion. Compound neurochords are multiple structures; each axon is connected to numerous cell…

cardiovascular disease: Vasoconstriction: …people or in those with neurocirculatory asthenia (a symptom-complex in which there is breathlessness, giddiness, a sense of fatigue, pain in the chest over the heart, palpitation, and a fast and forcible heartbeat of which the affected person is conscious). Reassurance and avoidance of cold help to eliminate attacks.

information processing: Basic concepts: …contributed to the development of neurocomputers, a new class of parallel, distributed-information processors that mimic the functioning of the human brain, including its capabilities for self-organization and learning. So-called neural networks, which are mathematical models inspired by the neural circuit network of the human brain, are increasingly finding applications in…

skull, skeletal framework of the head of vertebrates, composed of bones or cartilage, which form a unit that protects the brain and some sense organs. The upper jaw, but not the lower, is part of the skull. The human cranium, the part that contains the brain, is globular and relatively large in

dermatitis: Types of dermatitis: Neurodermatitis refers to a skin inflammation that is apparently caused by the patient’s own repeated and chronic scratching of an itchy area of skin.

neurodiversity, in sociology and psychology, is the natural variation in brain function and behavior among humans. The term neurodiversity was coined by Australian sociologist Judy Singer to provide an alternative to language that describes neurodevelopmental conditions, such as autism, in a way

nervous system: Neuroactive peptides: Some peptides are secreted by neuroendocrine cells of the hypothalamus or pituitary gland. Because they are released into the capillary system of the bloodstream and act at distant sites of the body, these are called neurohormones. Other peptides are released into the synaptic cleft between neurons of the central nervous…

neural engineering, in biomedicine, discipline in which engineering technologies and mathematical and computational methods are combined with techniques in neuroscience and biology. Objectives of neural engineering include the enhancement of understanding of the functions of the human nervous

human nervous system: Neuronal development: …precursor cells, known as neuroepithelial cells, which develop into the neural tube (see below Morphological development). Neuroepithelial cells then commence to divide, diversify, and give rise to immature neurons and neuroglia, which in turn migrate from the neural tube to their final location. Each neuron forms dendrites and an axon;…

human nervous system: Neuronal development: …neural precursor cells, known as neuroepithelial cells, which develop into the neural tube (see below Morphological development). Neuroepithelial cells then commence to divide, diversify, and give rise to immature neurons and neuroglia, which in turn migrate from the neural tube to their final location. Each neuron forms dendrites and an…

neuroethics, the study of the ethical, legal, and social implications of neuroscience and neurotechnology, as well as the neurobiological basis of human ethical norms and individual moral values. Neuroethics is an independent and highly interdisciplinary field, overlapping with subject areas such

neurofeedback, form of therapy in which the brain’s electrical activity is assessed and measured to help correct dysfunctional or abnormal brain-wave patterns. Techniques used to detect electrical rhythms in the brain include electroencephalography (EEG), functional magnetic resonance imaging

Alzheimer disease: Neuritic plaques and neurofibrillary tangles: The presence of neuritic plaques and neurofibrillary tangles in the brain are used to diagnose Alzheimer disease in autopsy. Neuritic plaques—also called senile, dendritic, or amyloid plaques—consist of deteriorating neuronal material surrounding deposits of a sticky protein called amyloid beta (or beta-amyloid). This…

neurofibromatosis, either of two hereditary disorders characterized by distinctive skin lesions and by benign, progressively enlarging tumours of the nervous system. Neurofibromatosis type 1, also known as von Recklinghausen’s disease, is much the more common of the two disorders and is present in

neurofibromatosis: Neurofibromatosis type 1, also known as von Recklinghausen’s disease, is much the more common of the two disorders and is present in about one of every 3,000 live births. This type is characterized by the presence of café-au-lait (pale brown) spots on the skin and…

neurofibromatosis: Neurofibromatosis type 2 is a much rarer inherited disease marked by tumours of the auditory canal in the ear and by small numbers of café-au-lait spots.

neuroplasticity: …as stroke recovery, natural adult neurogenesis can also play a role. As a result, neurogenesis has spurred an interest in stem cell research, which could lead to an enhancement of neurogenesis in adults who suffer from stroke, Alzheimer disease, Parkinson disease, or depression. Research suggests that Alzheimer disease in particular…

neurogenic arthropathy, condition characterized by the destruction of a stress-bearing joint, with development of new bone around the joint. Eventually the affected individual is unable to use the joint but experiences little or no pain or discomfort. The condition accompanies damage to the nervous

circulatory system: Fluid compartments: …of other invertebrates exhibit this neurogenic contraction.

diagnosis: Emergency: …by reduced heart function, and neurogenic shock and septic shock are caused by malfunction of the vascular system. This malfunction, which can be caused by severe allergic reaction such as anaphylaxis or by drug overdose, results in severely reduced peripheral vascular tone, in vasodilation, and in pooling of the blood.…

stuttering: Neurogenic stuttering is defined by abnormalities in signaling between the brain and the nerve fibres and muscles controlling speech. This form of stuttering is associated with structural damage in the motor speech area of the brain. Damage to this area may occur as a result…

neuroglia, any of several types of cell that function primarily to support neurons. The term neuroglia means “nerve glue.” In 1907 Italian biologist Emilio Lugaro suggested that neuroglial cells exchange substances with the extracellular fluid and in this way exert control on the neuronal

neuroglia, any of several types of cell that function primarily to support neurons. The term neuroglia means “nerve glue.” In 1907 Italian biologist Emilio Lugaro suggested that neuroglial cells exchange substances with the extracellular fluid and in this way exert control on the neuronal

Morton Prince: …formulated concepts such as the neurogram, or neurological record of psychological behaviour, and the coconscious, a parallel, possibly rival, well-organized system of awareness comparable to the ordinary, familiar consciousness.

hormone: Relationships between endocrine and neural regulation: …bloodstream at special regions called neurohemal organs, where the axon endings are in close contact with blood capillaries. Once released in this way, neurohormones function in principle similar to hormones that are transmitted in the bloodstream and are synthesized in the endocrine glands.

neurohormone, any of a group of substances that are produced by specialized neurosecretory cells of the nervous system, and that are released into the blood, similar to hormones of the endocrine system. Neurohormones pass along axons (portions of neurons that carry impulses away from the neuron

neurohormone, any of a group of substances that are produced by specialized neurosecretory cells of the nervous system, and that are released into the blood, similar to hormones of the endocrine system. Neurohormones pass along axons (portions of neurons that carry impulses away from the neuron

hormone: Hormones of the pituitary gland: One is the neurohypophysis, which forms as a downgrowth of the floor of the brain and gives rise to the median eminence and the neural lobe; these structures are neurohemal organs. The other is the adenohypophysis, which develops as an upgrowth from the buccal cavity (mouth region) and…

Schwann cell, any of the cells in the peripheral nervous system that produce the myelin sheath around neuronal axons. Schwann cells are named after German physiologist Theodor Schwann, who discovered them in the 19th century. These cells are equivalent to a type of neuroglia called

antipsychotic drug, any agent used in the treatment of psychosis, a form of mental illness. Psychoses can affect cognitive processes such as judgment and frequently cause delusions and hallucinations. The most widely known psychosis is schizophrenia. Effective treatments for some forms of

neurolinguistics, the study of the neurological mechanisms underlying the storage and processing of language. Although it has been fairly satisfactorily determined that the language centre is in the left hemisphere of the brain in right-handed people, controversy remains concerning whether

music therapy: Approaches in music therapy: …choose to be trained in neurologic music therapy (NMT). Training in this approach focuses on understanding and applying scientific, evidence-based practices, usually for the purpose of neurorehabilitation (the recovery of neurologic function). Examples of techniques employed in this approach include auditory perception training, patterned sensory enhancement, and therapeutic singing, which…

Harvey Williams Cushing: …are still basic to the surgery of the brain, and his work greatly reduced the high mortality rates that had formerly been associated with brain surgery. He became the leading expert in the diagnosis and treatment of intracranial tumours. His research on the pituitary body (1912) gained him an international…

automata theory: The finite automata of McCulloch and Pitts: …is often based on a model of a portion of the nervous system in a living creature and on how that system with its complex of neurons, nerve endings, and synapses (separating gap between neurons) can generate, codify, store, and use information. The “all or none” nature of the threshold…

neurology, medical specialty concerned with the nervous system and its functional or organic disorders. Neurologists diagnose and treat diseases and disorders of the brain, spinal cord, and nerves. The first scientific studies of nerve function in animals were performed in the early 18th century by

Neuromancer, novel (1984) by William Gibson that launched the cyberpunk movement within the science fiction literary genre. The novel, a fast-paced, gritty, Raymond Chandler-esque meditation on a computing-fueled dystopia of the near future, had an impact on many of its readers much like that of

lateral line system: …a series of mechanoreceptors called neuromasts (lateral line organs) arranged in an interconnected network along the head and body. This network is typically arranged in rows; however, neuromasts may also be organized singly. At its simplest, rows of neuromasts appear on the surface of the skin; however, for most fishes,…

hypothalamus: Hypothalamic regulation of hormone secretion: …as neurotransmitters but also as neuromodulators. As neuromodulators, they do not act directly as neurotransmitters but rather increase or decrease the action of neurotransmitters. Well-known examples are the opioids (e.g., enkephalins), so named because they are endogenous (produced in the human body) peptides (short chains of amino acids) with a…

drug: Drugs that affect skeletal muscle: The action of competitive neuromuscular blocking drugs can be reversed by anticholinesterases, which inhibit the rapid destruction of acetylcholine at the neuromuscular junction and thus enhance its action on the muscle fibre. Normally this has little effect, but, in the presence of a competitive neuromuscular blocking agent, transmission can…

neuromuscular junction, site of chemical communication between a nerve fibre and a muscle cell. The neuromuscular junction is analogous to the synapse between two neurons. A nerve fibre divides into many terminal branches; each terminal ends on a region of muscle fibre called the end plate.

neuron, basic cell of the nervous system in vertebrates and most invertebrates from the level of the cnidarians (e.g., corals, jellyfish) upward. A typical neuron has a cell body containing a nucleus and two or more long fibres. Impulses are carried along one or more of these fibres, called

nervous system: The nerve cell: …hypothesis, now known as the neuron theory, each nerve cell communicates with others through contiguity rather than continuity. That is, communication between adjacent but separate cells must take place across the space and barriers separating them. It has since been proved that Cajal’s theory is not universally true, but his…

Gerald Maurice Edelman: …brain development and function called neuronal group selection, which he explained in a trilogy of books (1987–89) for a scientific audience and in Bright Air, Brilliant Fire: On the Matter of the Mind (1992) for laypersons. He also wrote Wider than the Sky: The Phenomenal Gift of Consciousness (2004) and…

synapse, the site of transmission of electric nerve impulses between two nerve cells (neurons) or between a neuron and a gland or muscle cell (effector). A synaptic connection between a neuron and a muscle cell is called a neuromuscular junction. At a chemical synapse each ending, or terminal, of a

neuron, basic cell of the nervous system in vertebrates and most invertebrates from the level of the cnidarians (e.g., corals, jellyfish) upward. A typical neuron has a cell body containing a nucleus and two or more long fibres. Impulses are carried along one or more of these fibres, called

connectionism, an approach to artificial intelligence (AI) that developed out of attempts to understand how the human brain works at the neural level and, in particular, how people learn and remember. (For that reason, this approach is sometimes referred to as neuronlike computing.) In 1943 the

human nervous system: Neuronal development: …a target cell releases a trophic factor (e.g., nerve growth factor) that is essential for the survival of the neuron synapsing with it. Physical guidance cues are involved in contact guidance, or the migration of immature neurons along a scaffold of glial fibers.

keratitis: Neuroparalytic keratitis is inflammation of the cornea as a sequel to interruption of sensory impulses over the fifth (trigeminal) cranial nerve. The cornea’s loss of sensitivity leaves it much more subject to injury, exposure, and infection. This type of keratitis tends to lead to ulceration…

autism: Neuropathology: In the 1970s and ’80s, studies of children living with autism and postmortem investigations of autistic individuals led to the identification of associations between autism and minor physical anomalies, such as increased body size, enlarged head circumference, and increased brain weight. Later research comparing…

neuropathy, disorder of the peripheral nervous system. It may be genetic or acquired, progress quickly or slowly, involve motor, sensory, and autonomic (see autonomic nervous system) nerves, and affect only certain nerves or all of them. It can cause pain or loss of sensation, weakness, paralysis,

hypothalamus: Hypothalamic regulation of hormone secretion: …an important group is the neuropeptides. The neuropeptides function not only as neurotransmitters but also as neuromodulators. As neuromodulators, they do not act directly as neurotransmitters but rather increase or decrease the action of neurotransmitters. Well-known examples are the opioids (e.g., enkephalins), so named because they are endogenous (produced in…

stress: Types of stress and effects: …secretion of the neurotransmitter molecule neuropeptide Y, which promotes eating and weight gain.

hormone: Neurohypophysis and the polypeptide hormones of the hypothalamus: …bound to a protein called neurophysin (molecular weight of 20,000 to 25,000). In the neural lobe, which is the neurohemal organ of this neurosecretory system, the hormones separate from neurophysin and are released into the bloodstream.

Ragnar Arthur Granit: …of the Nobel Institute for Neurophysiology in Stockholm. In the 20 years from 1956 to 1976 Granit also served as a visiting professor or researcher at numerous institutions.

nervous system: Arthropods: …other organs, contains centres, or neuropils, such as the optic centres and bodies known as corpora pedunculata. The neuropils function as integrative systems for the anterior sense organs, especially the eyes, and in control of movement; they also are the centres for the initiation of complex behaviour. The deutocerebrum contains…

nervous system: Arthropods: …other organs, contains centres, or neuropils, such as the optic centres and bodies known as corpora pedunculata. The neuropils function as integrative systems for the anterior sense organs, especially the eyes, and in control of movement; they also are the centres for the initiation of complex behaviour. The deutocerebrum contains…

neuroplasticity, capacity of neurons and neural networks in the brain to change their connections and behaviour in response to new information, sensory stimulation, development, damage, or dysfunction. Although some neural functions appear to be hard-wired in specific, localized regions of the

cryonics: …preserved, a process known as neuropreservation. The option to cryonically preserve only a person’s head is based on the belief by many cryonics adherents that cryonically preserved personalities may one day be downloaded into robot bodies or be transferred into entirely new bodies grown from stem cells.

spinal cord injury: Spinal cord injury research: …progress toward the development of neuroprostheses, which harness electrical currents to help restore function in persons with nerve damage.

neuropsychiatry, area of science and medicine focused on the integrated study of psychiatric and neurological conditions and on the treatment of individuals with neurologically based disorders. In science, neuropsychiatry supports the field of neuroscience and is used to better understand the

neuropsychology, science concerned with the integration of psychological observations on behaviour with neurological observations on the central nervous system (CNS), including the brain. The field emerged through the work of Paul Broca and Carl Wernicke (1848–1905), both of whom identified sites

neuropteran, (order Neuroptera), any of a group of insects commonly called lacewings because of the complex vein patterns in the wings, giving them a lacy appearance. In a strict sense, the order Neuroptera includes only the lacewings. However, two other closely related insect groups are frequently

neuropteran, (order Neuroptera), any of a group of insects commonly called lacewings because of the complex vein patterns in the wings, giving them a lacy appearance. In a strict sense, the order Neuroptera includes only the lacewings. However, two other closely related insect groups are frequently

insect: Critical appraisal: The term neuropteran frequently is used to describe three closely related groups, classified here as three distinct orders: Neuroptera (lacewings), Raphidiodea (snakeflies), and Megaloptera (dobsonflies and alderflies). Although the tendency has been to classify these groups as distinct orders, they sometimes are placed in the order Neuroptera.

neuropteran, (order Neuroptera), any of a group of insects commonly called lacewings because of the complex vein patterns in the wings, giving them a lacy appearance. In a strict sense, the order Neuroptera includes only the lacewings. However, two other closely related insect groups are frequently

cognitive science: science, artificial intelligence (AI), neuroscience (see neurology), and anthropology. The term cognition, as used by cognitive scientists, refers to many kinds of thinking, including those involved in perception, problem solving, learning, decision making, language use,

neurosecretory cell, a type of neuron, or nerve cell, whose function is to translate neural signals into chemical stimuli. Such cells produce secretions called neurohormones that travel along the neuron axon and are typically released into the bloodstream at neurohemal organs, regions in which the

neurosis, generally outmoded term used to refer to mental disorders characterized by anxiety, depression, or other feelings of unhappiness or distress. Neuroses typically were associated with a sense of distress and a deficit in functioning to the extent that they threatened to impair a person’s

neurosis, generally outmoded term used to refer to mental disorders characterized by anxiety, depression, or other feelings of unhappiness or distress. Neuroses typically were associated with a sense of distress and a deficit in functioning to the extent that they threatened to impair a person’s

stem cell: Neural stem cells: …vitro in the form of neurospheres—small cell clusters that contain stem cells and some of their progeny. This type of stem cell is being studied for use in cell therapy to treat Parkinson disease and other forms of neurodegeneration or traumatic damage to the central nervous system.

Ascomycota: Neurospora, a genus of widespread species, produces bakery mold, or red bread mold. It has been used extensively in genetic and biochemical investigations. Xylaria contains about 100 species of cosmopolitan fungi. X. polymorpha produces a club-shaped or fingerlike fruiting body (stroma) resembling burned wood and…

one gene–one enzyme hypothesis: …their studies in the mold Neurospora crassa. Their experiments involved first exposing the mold to mutation-inducing X-rays and then culturing it in a minimal growth medium that contained only the basic nutrients that the wild-type, or nonmutated, strain of mold needed to survive. They found that the mutant strains of…

Harvey Williams Cushing: …are still basic to the surgery of the brain, and his work greatly reduced the high mortality rates that had formerly been associated with brain surgery. He became the leading expert in the diagnosis and treatment of intracranial tumours. His research on the pituitary body (1912) gained him an international…

The Fourth Industrial Revolution: …and skill in every industry; neurotechnology is making unprecedented strides in how we can use and influence the brain as the last frontier of human biology; automation is disrupting century-old transport and manufacturing paradigms; and technologies such as blockchain, used in executing cryptocurrency transactions, and smart materials are redefining and…

human digestive system: Neurotensin: Secreted by the N cells of the ileum in response to fat in the small intestine, neurotensin modulates motility, relaxes the lower esophageal sphincter, and blocks the stimulation of acid and pepsin secretion by the vagus nerve.

neurofeedback, form of therapy in which the brain’s electrical activity is assessed and measured to help correct dysfunctional or abnormal brain-wave patterns. Techniques used to detect electrical rhythms in the brain include electroencephalography (EEG), functional magnetic resonance imaging

Karen Horney: …produced her major theoretical works, The Neurotic Personality of Our Time (1937) and New Ways in Psychoanalysis (1939), in which she argued that environmental and social conditions, rather than the instinctual or biological drives described by Freud, determine much of individual personality and are the chief causes of neuroses and…

neuroticism, in psychology and development, a broad personality trait dimension representing the degree to which a person experiences the world as distressing, threatening, and unsafe. Each individual can be positioned somewhere on this personality dimension between extreme poles: perfect emotional

algae: Toxicity: Neurotoxic shellfish poisoning, caused by toxins produced in Gymnodinium breve, is notorious for fish kills and shellfish poisoning along the coast of Florida in the United States. When the red tide blooms are blown to shore, wind-sprayed toxic cells can cause health problems for humans…

neurotoxin, substance that alters the structure or function of the nervous system. More than 1,000 chemicals are known to have neurotoxic effects in animals. The substances include a wide range of natural and human-made chemical compounds, from snake venom and pesticides to ethyl alcohol, heroin,

neurotransmitter, any of a group of chemical agents released by neurons (nerve cells) to stimulate neighbouring neurons or muscle or gland cells, thus allowing impulses to be passed from one cell to the next throughout the nervous system. The following is an overview of neurotransmitter action and

neurotransmitter release, discharge of chemical substances known as neurotransmitters from a neuron in response to a given stimulus. Neurotransmitter release occurs at synapses, which are the sites of transmission of electric nerve impulses between two neurons or between a neuron and a gland or

mole: Mole diversity: The smallest mole is the American shrew mole (Neurotrichus gibbsii), which weighs only 7 to 11 grams (0.25 to 0.39 ounce) and has a body 3 to 4 cm (less than 2 inches) long and a slightly shorter tail. The largest is the Russian desman (Desmana moschata) of central Eurasia,…

prenatal development: Development between the second and fourth weeks: …is often designated as a neurula.

Nowa Sól, city, Lubuskie województwo (province), west-central Poland, on the Oder River. A railroad junction and port on the Oder, Nowa Sól has metalworks, paper and textile mills, and chemical and glue plants. A museum houses ethnographic and historical displays of the region. Pop. (2011)

Novi Sad, city and administrative capital of the ethnically mixed autonomous region of Vojvodina in northern Serbia. It is a transit port on the heavily trafficked Danube River northwest of Belgrade and is also situated on the Belgrade-Budapest rail line. Before the 18th century Novi Sad was a

Neuschwanstein Castle, elaborate castle near Füssen, Germany, built atop a rock ledge over the Pöllat Gorge in the Bavarian Alps by order of Bavaria’s King Louis II (“Mad King Ludwig”). Construction began in 1868 and was never completed. Louis II spent much of his childhood at Hohenschwangau

Kinston: …War the Confederate ironclad gunboat Neuse was sunk there by its crew in 1865 to keep it from being captured by Union forces; its hull, salvaged in 1963, lies on the riverbank, which has been designated a state historic site.