Anesthetics, Dissociative: Intravenous anesthetics that induce a state of sedation, immobility, amnesia, and marked analgesia. Subjects may experience a strong feeling of dissociation from the environment. The condition produced is similar to NEUROLEPTANALGESIA, but is brought about by the administration of a single drug. (From Gilman et al., Goodman and Gilman's The Pharmacological Basis of Therapeutics, 8th ed)Xylazine: An adrenergic alpha-2 agonist used as a sedative, analgesic and centrally acting muscle relaxant in VETERINARY MEDICINE.Analgesics: Compounds capable of relieving pain without the loss of CONSCIOUSNESS.Excitatory Amino Acid Antagonists: Drugs that bind to but do not activate excitatory amino acid receptors, thereby blocking the actions of agonists.Anesthetics, Combined: The use of two or more chemicals simultaneously or sequentially to induce anesthesia. The drugs need not be in the same dosage form.Anesthetics: Agents that are capable of inducing a total or partial loss of sensation, especially tactile sensation and pain. They may act to induce general ANESTHESIA, in which an unconscious state is achieved, or may act locally to induce numbness or lack of sensation at a targeted site.Midazolam: A short-acting hypnotic-sedative drug with anxiolytic and amnestic properties. It is used in dentistry, cardiac surgery, endoscopic procedures, as preanesthetic medication, and as an adjunct to local anesthesia. The short duration and cardiorespiratory stability makes it useful in poor-risk, elderly, and cardiac patients. It is water-soluble at pH less than 4 and lipid-soluble at physiological pH.Thiopental: A barbiturate that is administered intravenously for the induction of general anesthesia or for the production of complete anesthesia of short duration.Receptors, N-Methyl-D-Aspartate: A class of ionotropic glutamate receptors characterized by affinity for N-methyl-D-aspartate. NMDA receptors have an allosteric binding site for glycine which must be occupied for the channel to open efficiently and a site within the channel itself to which magnesium ions bind in a voltage-dependent manner. The positive voltage dependence of channel conductance and the high permeability of the conducting channel to calcium ions (as well as to monovalent cations) are important in excitotoxicity and neuronal plasticity.Depressive Disorder, Treatment-Resistant: Failure to respond to two or more trials of antidepressant monotherapy or failure to respond to four or more trials of different antidepressant therapies. (Campbell's Psychiatric Dictionary, 9th ed.)Acepromazine: A phenothiazine that is used in the treatment of PSYCHOSES.Anesthesia, Intravenous: Process of administering an anesthetic through injection directly into the bloodstream.Anesthetics, Intravenous: Ultrashort-acting anesthetics that are used for induction. Loss of consciousness is rapid and induction is pleasant, but there is no muscle relaxation and reflexes frequently are not reduced adequately. Repeated administration results in accumulation and prolongs the recovery time. Since these agents have little if any analgesic activity, they are seldom used alone except in brief minor procedures. (From AMA Drug Evaluations Annual, 1994, p174)Conscious Sedation: A drug-induced depression of consciousness during which patients respond purposefully to verbal commands, either alone or accompanied by light tactile stimulation. No interventions are required to maintain a patent airway. (From: American Society of Anesthesiologists Practice Guidelines)Propofol: An intravenous anesthetic agent which has the advantage of a very rapid onset after infusion or bolus injection plus a very short recovery period of a couple of minutes. (From Smith and Reynard, Textbook of Pharmacology, 1992, 1st ed, p206). Propofol has been used as ANTICONVULSANTS and ANTIEMETICS.Anesthesia: A state characterized by loss of feeling or sensation. This depression of nerve function is usually the result of pharmacologic action and is induced to allow performance of surgery or other painful procedures.Stereoisomerism: The phenomenon whereby compounds whose molecules have the same number and kind of atoms and the same atomic arrangement, but differ in their spatial relationships. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)Medetomidine: An agonist of RECEPTORS, ADRENERGIC ALPHA-2 that is used in veterinary medicine for its analgesic and sedative properties. It is the racemate of DEXMEDETOMIDINE.Adjuvants, Anesthesia: Agents that are administered in association with anesthetics to increase effectiveness, improve delivery, or decrease required dosage.Pentobarbital: A short-acting barbiturate that is effective as a sedative and hypnotic (but not as an anti-anxiety) agent and is usually given orally. It is prescribed more frequently for sleep induction than for sedation but, like similar agents, may lose its effectiveness by the second week of continued administration. (From AMA Drug Evaluations Annual, 1994, p236)Anesthesia, Caudal: Epidural anesthesia administered via the sacral canal.Psychoses, Substance-Induced: Psychotic organic mental disorders resulting from the toxic effect of drugs and chemicals or other harmful substance.Dose-Response Relationship, Drug: The relationship between the dose of an administered drug and the response of the organism to the drug.Anesthesia, General: Procedure in which patients are induced into an unconscious state through use of various medications so that they do not feel pain during surgery.Preanesthetic Medication: Drugs administered before an anesthetic to decrease a patient's anxiety and control the effects of that anesthetic.Pain, Postoperative: Pain during the period after surgery.Tiletamine: Proposed anesthetic with possible anticonvulsant and sedative properties.Double-Blind Method: A method of studying a drug or procedure in which both the subjects and investigators are kept unaware of who is actually getting which specific treatment.Analgesia: Methods of PAIN relief that may be used with or in place of ANALGESICS.Injections, Intramuscular: Forceful administration into a muscle of liquid medication, nutrient, or other fluid through a hollow needle piercing the muscle and any tissue covering it.Analgesics, Opioid: Compounds with activity like OPIATE ALKALOIDS, acting at OPIOID RECEPTORS. Properties include induction of ANALGESIA or NARCOSIS.Antidepressive Agents: Mood-stimulating drugs used primarily in the treatment of affective disorders and related conditions. Several MONOAMINE OXIDASE INHIBITORS are useful as antidepressants apparently as a long-term consequence of their modulation of catecholamine levels. The tricyclic compounds useful as antidepressive agents (ANTIDEPRESSIVE AGENTS, TRICYCLIC) also appear to act through brain catecholamine systems. A third group (ANTIDEPRESSIVE AGENTS, SECOND-GENERATION) is a diverse group of drugs including some that act specifically on serotonergic systems.Morphine: The principal alkaloid in opium and the prototype opiate analgesic and narcotic. Morphine has widespread effects in the central nervous system and on smooth muscle.Pain, Intractable: Persistent pain that is refractory to some or all forms of treatment.Pain Measurement: Scales, questionnaires, tests, and other methods used to assess pain severity and duration in patients or experimental animals to aid in diagnosis, therapy, and physiological studies.Fentanyl: A potent narcotic analgesic, abuse of which leads to habituation or addiction. It is primarily a mu-opioid agonist. Fentanyl is also used as an adjunct to general anesthetics, and as an anesthetic for induction and maintenance. (From Martindale, The Extra Pharmacopoeia, 30th ed, p1078)Drug Interactions: The action of a drug that may affect the activity, metabolism, or toxicity of another drug.Rats, Sprague-Dawley: A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.Zolazepam: A pyrazolodiazepinone with pharmacological actions similar to ANTI-ANXIETY AGENTS. It is commonly used in combination with TILETAMINE to obtain immobilization and anesthesia in animals.Phencyclidine: A hallucinogen formerly used as a veterinary anesthetic, and briefly as a general anesthetic for humans. Phencyclidine is similar to KETAMINE in structure and in many of its effects. Like ketamine, it can produce a dissociative state. It exerts its pharmacological action through inhibition of NMDA receptors (RECEPTORS, N-METHYL-D-ASPARTATE). As a drug of abuse, it is known as PCP and Angel Dust.Memantine: AMANTADINE derivative that has some dopaminergic effects. It has been proposed as an antiparkinson agent.Injections, Spinal: Introduction of therapeutic agents into the spinal region using a needle and syringe.Etomidate: Imidazole derivative anesthetic and hypnotic with little effect on blood gases, ventilation, or the cardiovascular system. It has been proposed as an induction anesthetic.Hallucinogens: Drugs capable of inducing illusions, hallucinations, delusions, paranoid ideations, and other alterations of mood and thinking. Despite the name, the feature that distinguishes these agents from other classes of drugs is their capacity to induce states of altered perception, thought, and feeling that are not experienced otherwise.Dizocilpine Maleate: A potent noncompetitive antagonist of the NMDA receptor (RECEPTORS, N-METHYL-D-ASPARTATE) used mainly as a research tool. The drug has been considered for the wide variety of neurodegenerative conditions or disorders in which NMDA receptors may play an important role. Its use has been primarily limited to animal and tissue experiments because of its psychotropic effects.Anesthesia, Dental: A range of methods used to reduce pain and anxiety during dental procedures.Respiration: The act of breathing with the LUNGS, consisting of INHALATION, or the taking into the lungs of the ambient air, and of EXHALATION, or the expelling of the modified air which contains more CARBON DIOXIDE than the air taken in (Blakiston's Gould Medical Dictionary, 4th ed.). This does not include tissue respiration (= OXYGEN CONSUMPTION) or cell respiration (= CELL RESPIRATION).Dexmedetomidine: A imidazole derivative that is an agonist of ADRENERGIC ALPHA-2 RECEPTORS. It is closely-related to MEDETOMIDINE, which is the racemic form of this compound.Diazepam: A benzodiazepine with anticonvulsant, anxiolytic, sedative, muscle relaxant, and amnesic properties and a long duration of action. Its actions are mediated by enhancement of GAMMA-AMINOBUTYRIC ACID activity.Dextromethorphan: Methyl analog of DEXTRORPHAN that shows high affinity binding to several regions of the brain, including the medullary cough center. This compound is an NMDA receptor antagonist (RECEPTORS, N-METHYL-D-ASPARTATE) and acts as a non-competitive channel blocker. It is one of the widely used ANTITUSSIVES, and is also used to study the involvement of glutamate receptors in neurotoxicity.Amnesia, Anterograde: Loss of the ability to form new memories beyond a certain point in time. This condition may be organic or psychogenic in origin. Organically induced anterograde amnesia may follow CRANIOCEREBRAL TRAUMA; SEIZURES; ANOXIA; and other conditions which adversely affect neural structures associated with memory formation (e.g., the HIPPOCAMPUS; FORNIX (BRAIN); MAMMILLARY BODIES; and ANTERIOR THALAMIC NUCLEI). (From Memory 1997 Jan-Mar;5(1-2):49-71)Infusions, Intravenous: The long-term (minutes to hours) administration of a fluid into the vein through venipuncture, either by letting the fluid flow by gravity or by pumping it.N-Methylaspartate: An amino acid that, as the D-isomer, is the defining agonist for the NMDA receptor subtype of glutamate receptors (RECEPTORS, NMDA).Anesthesia Recovery Period: The period of emergence from general anesthesia, where different elements of consciousness return at different rates.Adjuvants, Pharmaceutic: Agents that aid or increase the action of the principle drug (DRUG SYNERGISM) or that affect the absorption, mechanism of action, metabolism, or excretion of the primary drug (PHARMACOKINETICS) in such a way as to enhance its effects.Riluzole: A glutamate antagonist (RECEPTORS, GLUTAMATE) used as an anticonvulsant (ANTICONVULSANTS) and to prolong the survival of patients with AMYOTROPHIC LATERAL SCLEROSIS.Hyperalgesia: An increased sensation of pain or discomfort produced by mimimally noxious stimuli due to damage to soft tissue containing NOCICEPTORS or injury to a peripheral nerve.Halothane: A nonflammable, halogenated, hydrocarbon anesthetic that provides relatively rapid induction with little or no excitement. Analgesia may not be adequate. NITROUS OXIDE is often given concomitantly. Because halothane may not produce sufficient muscle relaxation, supplemental neuromuscular blocking agents may be required. (From AMA Drug Evaluations Annual, 1994, p178)Injections, Intravenous: Injections made into a vein for therapeutic or experimental purposes.Surgical Procedures, Minor: Surgery restricted to the management of minor problems and injuries; surgical procedures of relatively slight extent and not in itself hazardous to life. (Dorland, 28th ed & Stedman, 25th ed)Anesthesia, Rectal: Procedure involving the instillation of an anesthetic into the rectum.Neurotoxicity Syndromes: Neurologic disorders caused by exposure to toxic substances through ingestion, injection, cutaneous application, or other method. This includes conditions caused by biologic, chemical, and pharmaceutical agents.Nitrous Oxide: Nitrogen oxide (N2O). A colorless, odorless gas that is used as an anesthetic and analgesic. High concentrations cause a narcotic effect and may replace oxygen, causing death by asphyxia. It is also used as a food aerosol in the preparation of whipping cream.Brain: The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.Anesthetics, Inhalation: Gases or volatile liquids that vary in the rate at which they induce anesthesia; potency; the degree of circulation, respiratory, or neuromuscular depression they produce; and analgesic effects. Inhalation anesthetics have advantages over intravenous agents in that the depth of anesthesia can be changed rapidly by altering the inhaled concentration. Because of their rapid elimination, any postoperative respiratory depression is of relatively short duration. (From AMA Drug Evaluations Annual, 1994, p173)Cross-Over Studies: Studies comparing two or more treatments or interventions in which the subjects or patients, upon completion of the course of one treatment, are switched to another. In the case of two treatments, A and B, half the subjects are randomly allocated to receive these in the order A, B and half to receive them in the order B, A. A criticism of this design is that effects of the first treatment may carry over into the period when the second is given. (Last, A Dictionary of Epidemiology, 2d ed)Dissociative Disorders: Sudden temporary alterations in the normally integrative functions of consciousness.Secobarbital: A barbiturate that is used as a sedative. Secobarbital is reported to have no anti-anxiety activity.Heart Rate: The number of times the HEART VENTRICLES contract per unit of time, usually per minute.Administration, Rectal: The insertion of drugs into the rectum, usually for confused or incompetent patients, like children, infants, and the very old or comatose.Analgesia, Epidural: The relief of pain without loss of consciousness through the introduction of an analgesic agent into the epidural space of the vertebral canal. It is differentiated from ANESTHESIA, EPIDURAL which refers to the state of insensitivity to sensation.Drug Synergism: The action of a drug in promoting or enhancing the effectiveness of another drug.Rats, Wistar: A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.Electroencephalography: Recording of electric currents developed in the brain by means of electrodes applied to the scalp, to the surface of the brain, or placed within the substance of the brain.Nefopam: Non-narcotic analgesic chemically similar to ORPHENADRINE. Its mechanism of action is unclear. It is used for the relief of acute and chronic pain. (From Martindale, The Extra Pharmacopoeia, 30th ed, p26)Anesthetics, General: Agents that induce various degrees of analgesia; depression of consciousness, circulation, and respiration; relaxation of skeletal muscle; reduction of reflex activity; and amnesia. There are two types of general anesthetics, inhalation and intravenous. With either type, the arterial concentration of drug required to induce anesthesia varies with the condition of the patient, the desired depth of anesthesia, and the concomitant use of other drugs. (From AMA Drug Evaluations Annual, 1994, p.173)Isoflurane: A stable, non-explosive inhalation anesthetic, relatively free from significant side effects.Alfaxalone Alfadolone Mixture: A 3:1 mixture of alfaxalone with alfadolone acetate that previously had been used as a general anesthetic. It is no longer actively marketed. (From Martindale, The Extra Pharmacopoeia, 30th ed, p1445)Anesthesia, Inhalation: Anesthesia caused by the breathing of anesthetic gases or vapors or by insufflating anesthetic gases or vapors into the respiratory tract.Substance Abuse Detection: Detection of drugs that have been abused, overused, or misused, including legal and illegal drugs. Urine screening is the usual method of detection.Anesthetics, Local: Drugs that block nerve conduction when applied locally to nerve tissue in appropriate concentrations. They act on any part of the nervous system and on every type of nerve fiber. In contact with a nerve trunk, these anesthetics can cause both sensory and motor paralysis in the innervated area. Their action is completely reversible. (From Gilman AG, et. al., Goodman and Gilman's The Pharmacological Basis of Therapeutics, 8th ed) Nearly all local anesthetics act by reducing the tendency of voltage-dependent sodium channels to activate.Drug Combinations: Single preparations containing two or more active agents, for the purpose of their concurrent administration as a fixed dose mixture.Pain: An unpleasant sensation induced by noxious stimuli which are detected by NERVE ENDINGS of NOCICEPTIVE NEURONS.Behavior, Animal: The observable response an animal makes to any situation.Preservatives, Pharmaceutical: Substances added to pharmaceutical preparations to protect them from chemical change or microbial action. They include ANTI-BACTERIAL AGENTS and antioxidants.Tilidine: An opioid analgesic used similarly to MORPHINE in the control of moderate to severe pain. (From Martindale, The Extra Pharmacopoeia, 30th ed, p1097)Chlorobutanol: A colorless to white crystalline compound with a camphoraceous odor and taste. It is a widely used preservative in various pharmaceutical solutions, especially injectables. Also, it is an active ingredient in certain oral sedatives and topical anesthetics.Levorphanol: A narcotic analgesic that may be habit-forming. It is nearly as effective orally as by injection.Methohexital: An intravenous anesthetic with a short duration of action that may be used for induction of anesthesia.Complex Regional Pain Syndromes: Conditions characterized by pain involving an extremity or other body region, HYPERESTHESIA, and localized autonomic dysfunction following injury to soft tissue or nerve. The pain is usually associated with ERYTHEMA; SKIN TEMPERATURE changes, abnormal sudomotor activity (i.e., changes in sweating due to altered sympathetic innervation) or edema. The degree of pain and other manifestations is out of proportion to that expected from the inciting event. Two subtypes of this condition have been described: type I; (REFLEX SYMPATHETIC DYSTROPHY) and type II; (CAUSALGIA). (From Pain 1995 Oct;63(1):127-33)Silver Staining: The use of silver, usually silver nitrate, as a reagent for producing contrast or coloration in tissue specimens.Blood Pressure: PRESSURE of the BLOOD on the ARTERIES and other BLOOD VESSELS.Pain Threshold: Amount of stimulation required before the sensation of pain is experienced.Lidocaine: A local anesthetic and cardiac depressant used as an antiarrhythmia agent. Its actions are more intense and its effects more prolonged than those of PROCAINE but its duration of action is shorter than that of BUPIVACAINE or PRILOCAINE.Droperidol: A butyrophenone with general properties similar to those of HALOPERIDOL. It is used in conjunction with an opioid analgesic such as FENTANYL to maintain the patient in a calm state of neuroleptanalgesia with indifference to surroundings but still able to cooperate with the surgeon. It is also used as a premedicant, as an antiemetic, and for the control of agitation in acute psychoses. (From Martindale, The Extra Pharmacopoeia, 29th ed, p593)Drug Tolerance: Progressive diminution of the susceptibility of a human or animal to the effects of a drug, resulting from its continued administration. It should be differentiated from DRUG RESISTANCE wherein an organism, disease, or tissue fails to respond to the intended effectiveness of a chemical or drug. It should also be differentiated from MAXIMUM TOLERATED DOSE and NO-OBSERVED-ADVERSE-EFFECT LEVEL.Street Drugs: Drugs obtained and often manufactured illegally for the subjective effects they are said to produce. They are often distributed in urban areas, but are also available in suburban and rural areas, and tend to be grossly impure and may cause unexpected toxicity.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Promethazine: A phenothiazine derivative with histamine H1-blocking, antimuscarinic, and sedative properties. It is used as an antiallergic, in pruritus, for motion sickness and sedation, and also in animals.Analgesia, Patient-Controlled: Relief of PAIN, without loss of CONSCIOUSNESS, through ANALGESIC AGENTS administered by the patients. It has been used successfully to control POSTOPERATIVE PAIN, during OBSTETRIC LABOR, after BURNS, and in TERMINAL CARE. The choice of agent, dose, and lockout interval greatly influence effectiveness. The potential for overdose can be minimized by combining small bolus doses with a mandatory interval between successive doses (lockout interval).Dibenzocycloheptenes: A family of tricyclic hydrocarbons whose members include many of the commonly used tricyclic antidepressants (ANTIDEPRESSIVE AGENTS, TRICYCLIC).Sodium Oxybate: The sodium salt of 4-hydroxybutyric acid. It is used for both induction and maintenance of ANESTHESIA.Ocular Motility Disorders: Disorders that feature impairment of eye movements as a primary manifestation of disease. These conditions may be divided into infranuclear, nuclear, and supranuclear disorders. Diseases of the eye muscles or oculomotor cranial nerves (III, IV, and VI) are considered infranuclear. Nuclear disorders are caused by disease of the oculomotor, trochlear, or abducens nuclei in the BRAIN STEM. Supranuclear disorders are produced by dysfunction of higher order sensory and motor systems that control eye movements, including neural networks in the CEREBRAL CORTEX; BASAL GANGLIA; CEREBELLUM; and BRAIN STEM. Ocular torticollis refers to a head tilt that is caused by an ocular misalignment. Opsoclonus refers to rapid, conjugate oscillations of the eyes in multiple directions, which may occur as a parainfectious or paraneoplastic condition (e.g., OPSOCLONUS-MYOCLONUS SYNDROME). (Adams et al., Principles of Neurology, 6th ed, p240)Deep Sedation: Drug-induced depression of consciousness during which patients cannot be easily aroused but respond purposely following repeated painful stimulation. The ability to independently maintain ventilatory function may be impaired. (From: American Society of Anesthesiologists Practice Guidelines)Glutamic Acid: A non-essential amino acid naturally occurring in the L-form. Glutamic acid is the most common excitatory neurotransmitter in the CENTRAL NERVOUS SYSTEM.Ether: A mobile, very volatile, highly flammable liquid used as an inhalation anesthetic and as a solvent for waxes, fats, oils, perfumes, alkaloids, and gums. It is mildly irritating to skin and mucous membranes.Reflex, Righting: The instinctive tendency (or ability) to assume a normal position of the body in space when it has been displaced.Evoked Potentials, Auditory: The electric response evoked in the CEREBRAL CORTEX by ACOUSTIC STIMULATION or stimulation of the AUDITORY PATHWAYS.Reaction Time: The time from the onset of a stimulus until a response is observed.Hemodynamics: The movement and the forces involved in the movement of the blood through the CARDIOVASCULAR SYSTEM.Urethane: Antineoplastic agent that is also used as a veterinary anesthetic. It has also been used as an intermediate in organic synthesis. Urethane is suspected to be a carcinogen.Adrenergic alpha-Agonists: Drugs that selectively bind to and activate alpha adrenergic receptors.Neurons: The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.Enflurane: An extremely stable inhalation anesthetic that allows rapid adjustments of anesthesia depth with little change in pulse or respiratory rate.Electric Stimulation: Use of electric potential or currents to elicit biological responses.Disease Models, Animal: Naturally occurring or experimentally induced animal diseases with pathological processes sufficiently similar to those of human diseases. They are used as study models for human diseases.Anxiety, Separation: Anxiety experienced by an individual upon separation from a person or object of particular significance to the individual.Blood Gas Analysis: Measurement of oxygen and carbon dioxide in the blood.Cerebral Cortex: The thin layer of GRAY MATTER on the surface of the CEREBRAL HEMISPHERES that develops from the TELENCEPHALON and folds into gyri and sulchi. It reaches its highest development in humans and is responsible for intellectual faculties and higher mental functions.Spinal Cord: A cylindrical column of tissue that lies within the vertebral canal. It is composed of WHITE MATTER and GRAY MATTER.Dancing: Rhythmic and patterned body movements which are usually performed to music.Extrapyramidal Tracts: Uncrossed tracts of motor nerves from the brain to the anterior horns of the spinal cord, involved in reflexes, locomotion, complex movements, and postural control.Hallucinations: Subjectively experienced sensations in the absence of an appropriate stimulus, but which are regarded by the individual as real. They may be of organic origin or associated with MENTAL DISORDERS.Anti-Anxiety Agents: Agents that alleviate ANXIETY, tension, and ANXIETY DISORDERS, promote sedation, and have a calming effect without affecting clarity of consciousness or neurologic conditions. ADRENERGIC BETA-ANTAGONISTS are commonly used in the symptomatic treatment of anxiety but are not included here.Schizophrenia: A severe emotional disorder of psychotic depth characteristically marked by a retreat from reality with delusion formation, HALLUCINATIONS, emotional disharmony, and regressive behavior.Electroencephalography Phase Synchronization: Adjustment of BRAIN WAVES from two or more neuronal groups within or across a brain structure (e.g., cortical and limbic brain structures) to become uniform in EEG oscillation patterns in response to a stimulus. It is interpreted as a brain integration sign during many processes such as learning, memory, and perception and involves reciprocal neural connections.Analysis of Variance: A statistical technique that isolates and assesses the contributions of categorical independent variables to variation in the mean of a continuous dependent variable.Drug Therapy, Combination: Therapy with two or more separate preparations given for a combined effect.Anesthesia, IntratrachealAlfentanil: A short-acting opioid anesthetic and analgesic derivative of FENTANYL. It produces an early peak analgesic effect and fast recovery of consciousness. Alfentanil is effective as an anesthetic during surgery, for supplementation of analgesia during surgical procedures, and as an analgesic for critically ill patients.Hippocampus: A curved elevation of GRAY MATTER extending the entire length of the floor of the TEMPORAL HORN of the LATERAL VENTRICLE (see also TEMPORAL LOBE). The hippocampus proper, subiculum, and DENTATE GYRUS constitute the hippocampal formation. Sometimes authors include the ENTORHINAL CORTEX in the hippocampal formation.Status Epilepticus: A prolonged seizure or seizures repeated frequently enough to prevent recovery between episodes occurring over a period of 20-30 minutes. The most common subtype is generalized tonic-clonic status epilepticus, a potentially fatal condition associated with neuronal injury and respiratory and metabolic dysfunction. Nonconvulsive forms include petit mal status and complex partial status, which may manifest as behavioral disturbances. Simple partial status epilepticus consists of persistent motor, sensory, or autonomic seizures that do not impair cognition (see also EPILEPSIA PARTIALIS CONTINUA). Subclinical status epilepticus generally refers to seizures occurring in an unresponsive or comatose individual in the absence of overt signs of seizure activity. (From N Engl J Med 1998 Apr 2;338(14):970-6; Neurologia 1997 Dec;12 Suppl 6:25-30)Butorphanol: A synthetic morphinan analgesic with narcotic antagonist action. It is used in the management of severe pain.Random Allocation: A process involving chance used in therapeutic trials or other research endeavor for allocating experimental subjects, human or animal, between treatment and control groups, or among treatment groups. It may also apply to experiments on inanimate objects.Arachnoiditis: Acute or chronic inflammation of the arachnoid membrane of the meninges most often involving the spinal cord or base of the brain. This term generally refers to a persistent inflammatory process characterized by thickening of the ARACHNOID membrane and dural adhesions. Associated conditions include prior surgery, infections, trauma, SUBARACHNOID HEMORRHAGE, and chemical irritation. Clinical features vary with the site of inflammation, but include cranial neuropathies, radiculopathies, and myelopathies. (From Joynt, Clinical Neurology, 1997, Ch48, p25)Tramadol: A narcotic analgesic proposed for severe pain. It may be habituating.Neuralgia: Intense or aching pain that occurs along the course or distribution of a peripheral or cranial nerve.Solid Phase Microextraction: A solventless sample preparation method, invented in 1989, that uses a fused silica fiber which is coated with a stationary phase. It is used for sample cleanup before using other analytical methods.Premedication: Preliminary administration of a drug preceding a diagnostic, therapeutic, or surgical procedure. The commonest types of premedication are antibiotics (ANTIBIOTIC PROPHYLAXIS) and anti-anxiety agents. It does not include PREANESTHETIC MEDICATION.Bupivacaine: A widely used local anesthetic agent.Evoked Potentials: Electrical responses recorded from nerve, muscle, SENSORY RECEPTOR, or area of the CENTRAL NERVOUS SYSTEM following stimulation. They range from less than a microvolt to several microvolts. The evoked potential can be auditory (EVOKED POTENTIALS, AUDITORY), somatosensory (EVOKED POTENTIALS, SOMATOSENSORY), visual (EVOKED POTENTIALS, VISUAL), or motor (EVOKED POTENTIALS, MOTOR), or other modalities that have been reported.Piperidines: A family of hexahydropyridines.Delta Rhythm: Brain waves seen on EEG characterized by a high amplitude and a frequency of 4 Hz and below. They are considered the "deep sleep waves" observed during sleep in dreamless states, infancy, and in some brain disorders.Motor Activity: The physical activity of a human or an animal as a behavioral phenomenon.Gas Chromatography-Mass Spectrometry: A microanalytical technique combining mass spectrometry and gas chromatography for the qualitative as well as quantitative determinations of compounds.Injections, Intraperitoneal: Forceful administration into the peritoneal cavity of liquid medication, nutrient, or other fluid through a hollow needle piercing the abdominal wall.Immobility Response, Tonic: An induced response to threatening stimuli characterized by complete loss of muscle strength.Depressive Disorder, Major: Marked depression appearing in the involution period and characterized by hallucinations, delusions, paranoia, and agitation.Monitoring, Intraoperative: The constant checking on the state or condition of a patient during the course of a surgical operation (e.g., checking of vital signs).Electrophysiological Processes: The functions and activities of living organisms or their parts involved in generating and responding to electrical charges .Chronotherapy: The adaptation of therapeutic approaches such as pharmacological (DRUG CHRONOTHERAPY), surgical, radiological, or physical to the known variations in biological RHYTHMICITY, such as CIRCADIAN RHYTHMS. The treatment is aimed at supporting normal rhythms, or modifying the timing of therapy to achieve maximal efficacy and minimal adverse effect.Epilepsy, Reflex: A subtype of epilepsy characterized by seizures that are consistently provoked by a certain specific stimulus. Auditory, visual, and somatosensory stimuli as well as the acts of writing, reading, eating, and decision making are examples of events or activities that may induce seizure activity in affected individuals. (From Neurol Clin 1994 Feb;12(1):57-8)Arab World: A historical and cultural entity dispersed across a wide geographical area under the administrative, intellectual, social, and cultural domination of the Arab empire. The Arab world, under the impetus of Islam, by the eighth century A.D., extended from Arabia in the Middle East to all of northern Africa, southern Spain, Sardinia, and Sicily. Close contact was maintained with Greek and Jewish culture. While the principal service of the Arabs to medicine was the preservation of Greek culture, the Arabs themselves were the originators of algebra, chemistry, geology, and many of the refinements of civilization. (From A. Castiglioni, A History of Medicine, 2d ed, p260; from F. H. Garrison, An Introduction to the History of Medicine, 4th ed, p126)Hypotension: Abnormally low BLOOD PRESSURE that can result in inadequate blood flow to the brain and other vital organs. Common symptom is DIZZINESS but greater negative impacts on the body occur when there is prolonged depravation of oxygen and nutrients.Acute Pain: Intensely discomforting, distressful, or agonizing sensation associated with trauma or disease, with well-defined location, character, and timing.Chronobiology Phenomena: Biological systems as affected by time. Aging, biological rhythms, and cyclic phenomena are included. Statistical, computer-aided mathematical procedures are used to describe, in mathematical terminology, various biological functions over time.Unconsciousness: Loss of the ability to maintain awareness of self and environment combined with markedly reduced responsiveness to environmental stimuli. (From Adams et al., Principles of Neurology, 6th ed, pp344-5)Bupranolol: An adrenergic-beta-2 antagonist that has been used for cardiac arrhythmia, angina pectoris, hypertension, glaucoma, and as an antithrombotic.Prospective Studies: Observation of a population for a sufficient number of persons over a sufficient number of years to generate incidence or mortality rates subsequent to the selection of the study group.Spinal Nerves: The 31 paired peripheral nerves formed by the union of the dorsal and ventral spinal roots from each spinal cord segment. The spinal nerve plexuses and the spinal roots are also included.Yang Deficiency: In the YIN-YANG system of philosophy and medicine, a lack of vital energy (called yangxu in Chinese). It manifests itself in various systemic and organic diseases. (The Pinyin Chinese-English Dictionary, 1979)Receptors, Opioid, kappa: A class of opioid receptors recognized by its pharmacological profile. Kappa opioid receptors bind dynorphins with a higher affinity than endorphins which are themselves preferred to enkephalins.Psilocybine: The major of two hallucinogenic components of Teonanacatl, the sacred mushroom of Mexico, the other component being psilocin. (From Merck Index, 11th ed)Barbiturates: A class of chemicals derived from barbituric acid or thiobarbituric acid. Many of these are GABA MODULATORS used as HYPNOTICS AND SEDATIVES, as ANESTHETICS, or as ANTICONVULSANTS.Rabbits: The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.Sufentanil: An opioid analgesic that is used as an adjunct in anesthesia, in balanced anesthesia, and as a primary anesthetic agent.Thalamic Diseases: Disorders of the centrally located thalamus, which integrates a wide range of cortical and subcortical information. Manifestations include sensory loss, MOVEMENT DISORDERS; ATAXIA, pain syndromes, visual disorders, a variety of neuropsychological conditions, and COMA. Relatively common etiologies include CEREBROVASCULAR DISORDERS; CRANIOCEREBRAL TRAUMA; BRAIN NEOPLASMS; BRAIN HYPOXIA; INTRACRANIAL HEMORRHAGES; and infectious processes.Euphoria: An exaggerated feeling of physical and emotional well-being not consonant with apparent stimuli or events; usually of psychologic origin, but also seen in organic brain disease and toxic states.Placebos: Any dummy medication or treatment. Although placebos originally were medicinal preparations having no specific pharmacological activity against a targeted condition, the concept has been extended to include treatments or procedures, especially those administered to control groups in clinical trials in order to provide baseline measurements for the experimental protocol.Healthy Volunteers: Persons with no known significant health problems who are recruited to participate in research to test a new drug, device, or intervention as controls for a patient group. (from, accessed 2/14/2013)Chloral Hydrate: A hypnotic and sedative used in the treatment of INSOMNIA.Rotarod Performance Test: A performance test based on forced MOTOR ACTIVITY on a rotating rod, usually by a rodent. Parameters include the riding time (seconds) or endurance. Test is used to evaluate balance and coordination of the subjects, particular in experimental animal models for neurological disorders and drug effects.KATP Channels: Heteromultimers of Kir6 channels (the pore portion) and sulfonylurea receptor (the regulatory portion) which affect function of the HEART; PANCREATIC BETA CELLS; and KIDNEY COLLECTING DUCTS. KATP channel blockers include GLIBENCLAMIDE and mitiglinide whereas openers include CROMAKALIM and minoxidil sulfate.Autonomic Fibers, Postganglionic: Nerve fibers which project from cell bodies of AUTONOMIC GANGLIA to SYNAPSES on target organs.Substance-Related Disorders: Disorders related to substance abuse.Depression, Chemical: The decrease in a measurable parameter of a PHYSIOLOGICAL PROCESS, including cellular, microbial, and plant; immunological, cardiovascular, respiratory, reproductive, urinary, digestive, neural, musculoskeletal, ocular, and skin physiological processes; or METABOLIC PROCESS, including enzymatic and other pharmacological processes, by a drug or other chemical.Swimming: An activity in which the body is propelled through water by specific movement of the arms and/or the legs. Swimming as propulsion through water by the movement of limbs, tail, or fins of animals is often studied as a form of PHYSICAL EXERTION or endurance.Oxygen: An element with atomic symbol O, atomic number 8, and atomic weight [15.99903; 15.99977]. It is the most abundant element on earth and essential for respiration.Administration, Oral: The giving of drugs, chemicals, or other substances by mouth.Macaca mulatta: A species of the genus MACACA inhabiting India, China, and other parts of Asia. The species is used extensively in biomedical research and adapts very well to living with humans.Cerium Radioisotopes: Unstable isotopes of cerium that decay or disintegrate emitting radiation. Ce atoms with atomic weights 132-135, 137, 139, and 141-148 are radioactive cerium isotopes.Sutures: Materials used in closing a surgical or traumatic wound. (From Dorland, 28th ed)Orphenadrine: A muscarinic antagonist used to treat drug-induced parkinsonism and to relieve pain from muscle spasm.Flunitrazepam: A benzodiazepine with pharmacologic actions similar to those of DIAZEPAM that can cause ANTEROGRADE AMNESIA. Some reports indicate that it is used as a date rape drug and suggest that it may precipitate violent behavior. The United States Government has banned the importation of this drug.Cats: The domestic cat, Felis catus, of the carnivore family FELIDAE, comprising over 30 different breeds. The domestic cat is descended primarily from the wild cat of Africa and extreme southwestern Asia. Though probably present in towns in Palestine as long ago as 7000 years, actual domestication occurred in Egypt about 4000 years ago. (From Walker's Mammals of the World, 6th ed, p801)Psychiatric Status Rating Scales: Standardized procedures utilizing rating scales or interview schedules carried out by health personnel for evaluating the degree of mental illness.Reflex: An involuntary movement or exercise of function in a part, excited in response to a stimulus applied to the periphery and transmitted to the brain or spinal cord.Body Temperature: The measure of the level of heat of a human or animal.Electrophysiology: The study of the generation and behavior of electrical charges in living organisms particularly the nervous system and the effects of electricity on living organisms.Quisqualic Acid: An agonist at two subsets of excitatory amino acid receptors, ionotropic receptors that directly control membrane channels and metabotropic receptors that indirectly mediate calcium mobilization from intracellular stores. The compound is obtained from the seeds and fruit of Quisqualis chinensis.Glycine Plasma Membrane Transport Proteins: A family of sodium chloride-dependent neurotransmitter symporters that transport the amino acid GLYCINE. They differ from GLYCINE RECEPTORS, which signal cellular responses to GLYCINE. They are located primarily on the PLASMA MEMBRANE of NEURONS; GLIAL CELLS; EPITHELIAL CELLS; and RED BLOOD CELLS where they remove inhibitory neurotransmitter glycine from the EXTRACELLULAR SPACE.Apnea: A transient absence of spontaneous respiration.Yin Deficiency: In the YIN-YANG system of philosophy and medicine, an insufficiency of body fluid (called yinxu), manifesting often as irritability, thirst, constipation, etc. (The Pinyin Chinese-English Dictionary, 1979).Diprenorphine: A narcotic antagonist similar in action to NALOXONE. It is used to remobilize animals after ETORPHINE neuroleptanalgesia and is considered a specific antagonist to etorphine.Affect: The feeling-tone accompaniment of an idea or mental representation. It is the most direct psychic derivative of instinct and the psychic representative of the various bodily changes by means of which instincts manifest themselves.Ambulatory Surgical Procedures: Surgery performed on an outpatient basis. It may be hospital-based or performed in an office or surgicenter.Methyl Ethers: A group of compounds that contain the general formula R-OCH3.Biophysical Processes: Physical forces and actions in living things.gamma-Aminobutyric Acid: The most common inhibitory neurotransmitter in the central nervous system.Sialorrhea: Increased salivary flow.Pulpitis: Inflammation of the DENTAL PULP, usually due to bacterial infection in dental caries, tooth fracture, or other conditions causing exposure of the pulp to bacterial invasion. Chemical irritants, thermal factors, hyperemic changes, and other factors may also cause pulpitis.