Author: Glossary
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N-methyl-D-aspartic acid
A compound that acts as a specific agonist at the NMDA receptor, mimicking the effects of the neurotransmitter glutamate.
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Nitrous oxide
Laughing gas; it rapidly produces intoxication, with light-headedness and a floating sensation. Symptoms disappear within minutes after discontinuation of the substance; however, temporary but clinically relevant confusion and reversible paranoid states have followed regular use. An anesthetic gas sometimes used recreationally as an inhalant. A colourless gas with a sweet smell, used in combination with…
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Nitrite inhalants
Inhaled substances (street name: “poppers”), including amyl, butyl, and isobutyl nitrite, that produce an intoxication characterized by a feeling of fullness in the head, mild euphoria, a change in the perception of time, relaxation of smooth muscles, and possibly an increase in sexual feelings. The nitrites may produce psychological dependence and may impair immune functioning,…
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Nihilistic delusion
The delusion of nonexistence of the self or part of the self, or of some object in external reality. A fixed belief that everything is unreal, that nothing really exists. A delusion that everything has ceased to exist.
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Nightmare disorder
Dream anxiety disorder; a parasomnia consisting of repeated awakenings from sleep with detailed recall of extended and extremely frightening dreams, usually involving threats to survival, security, or self-esteem. On awakening from the frightening dream, the person rapidly becomes oriented and alert. This contrasts with the confusion and disorientation characteristic of sleep terror disorder and some…
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Nicotinic receptors
A subtype of cholinergic receptor specifically responsive to nicotine. Specialized cells within the central nervous system that are sensitive to the level of nicotine in body tissues. A cholinergic receptor found at the neuromuscular junction on skeletal muscle and in the autonomic ganglia, which responds to nicotine and nicotine-like drugs. A primary class of cholinergic…
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Nicotine-related disorders
In dsm-iv-tr, a group of mental disorders that includes nicotine dependence and nicotine withdrawal.
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Neurotic process
A specific etiological process involving the following sequence: unconscious conflicts between opposing wishes or between wishes and prohibitions lead to unconscious perception of anticipated danger or dysphoria, which leads to use of defense mechanisms that result in either symptoms, personality disturbance, or both.
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Neuroticism
An enduring tendency to experience negative emotional states. Individuals who score high on measures of neuroticism are more likely than the average person to experience such feelings as anxiety, anger, guilt, and depression. They respond more poorly to environmental stress and are more likely to interpret ordinary situations as threatening and minor frustrations as hopelessly…
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Neurotic disorder
An older term for a mental disorder in which the predominant disturbance is a distressing symptom or group of symptoms that one considers unacceptable to one’s personality. There is no marked loss of reality testing; behavior does not actively violate social norms, although it may be quite disabling. The disturbance is relatively enduring or recurrent…