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Hyperosmia
Hyperosmia is an increased olfactory acuity (heightened sense of smell), usually caused by a lower threshold for odor. This perceptual disorder arises when there is an abnormally increased signal at any point between the olfactory receptors and the olfactory cortex. The causes of hyperosmia may be genetic, hormonal, environmental or the result of benzodiazepine withdrawal syndrome. Causes Genetics A study by Menashe et al. has found that individuals with a single nucleotide polymorphism variant in the OR11H7P pseudogene have a lower receptor activation threshold for isovaleric acid. These individuals are hyperosmic for this single odorant. Another study by Keller et al. has found that people with the intact human odorant receptor OR7D4 are more sensitive to androstenone and androstadienone and thus find them unpleasant (individuals with the semi-functional OR7D4 have two non-synonymous single nucleotide polymorphisms in the OR7D4 pseudogene, resulting in two amino acid substi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Olfactory
The sense of smell, or olfaction, is the special sense through which smells (or odors) are perceived. The sense of smell has many functions, including detecting desirable foods, hazards, and pheromones, and plays a role in taste. In humans, it occurs when an odor binds to a receptor within the nasal cavity, transmitting a signal through the olfactory system. Glomeruli aggregate signals from these receptors and transmit them to the olfactory bulb, where the sensory input will start to interact with parts of the brain responsible for smell identification, memory, and emotion. There are many different things which can interfere with a normal sense of smell, including damage to the nose or smell receptors, anosmia, upper respiratory infections, traumatic brain injury, and neurodegenerative disease. History of study Early scientific study of the sense of smell includes the extensive doctoral dissertation of Eleanor Gamble, published in 1898, which compared olfactory to othe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benzodiazepine Withdrawal Syndrome
Benzodiazepine withdrawal syndrome (BZD withdrawal) is the cluster of signs and symptoms that may emerge when a person who has been taking benzodiazepines as prescribed develops a physical dependence on them and then reduces the dose or stops taking them without a safe taper schedule. Typically, benzodiazepine withdrawal is characterized by sleep disturbance, irritability, increased tension and anxiety, depression, panic attacks, hand tremor, shaking, sweating, difficulty with concentration, confusion and cognitive difficulty, memory problems, dry mouth, nausea and vomiting, diarrhea, loss of appetite and weight loss, burning sensations and pain in the upper spine, palpitations, headache, nightmares, tinnitus, muscular pain and stiffness, and a host of perceptual changes. More serious symptoms may also occur such as depersonalization, restless legs syndrome, seizures, and suicidal ideation. Benzodiazepine withdrawal can also lead to disturbances in mental function ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Olfaction
The sense of smell, or olfaction, is the special sense through which smells (or odors) are perceived. The sense of smell has many functions, including detecting desirable foods, hazards, and pheromones, and plays a role in taste. In humans, it occurs when an odor binds to a receptor within the nasal cavity, transmitting a signal through the olfactory system. Glomeruli aggregate signals from these receptors and transmit them to the olfactory bulb, where the sensory input will start to interact with parts of the brain responsible for smell identification, memory, and emotion. There are many different things which can interfere with a normal sense of smell, including damage to the nose or smell receptors, anosmia, upper respiratory infections, traumatic brain injury, and neurodegenerative disease. History of study Early scientific study of the sense of smell includes the extensive doctoral dissertation of Eleanor Gamble, published in 1898, which compared olfactory to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multiple Chemical Sensitivity
Multiple chemical sensitivity (MCS) is an unrecognized and controversial diagnosis characterized by chronic symptoms attributed to exposure to low levels of commonly used chemicals. Symptoms are typically vagueness, vague and non-specific symptoms, non-specific. They may include fatigue (medical), fatigue, headaches, nausea, and dizziness. Recent imaging studies have shown that it is likely a Neurology, neurological condition. MCS is a chronic disease that requires ongoing management. In the long term, about half of people with MCS get better and about half continue to be affected, sometimes severely. Classification In nosological terms, MCS may be more than one disease. It is generally considered a subtype of non-allergic chemical intolerance (also called ''chemical sensitivity''). MCS is considered an acquired disorder, meaning that it was not present from birth but instead developed later. Compared to other conditions with medically unexplained physical symptoms, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hyposmia
Hyposmia, or microsmia, is a reduced ability to smell and to detect odors. A related condition is anosmia, in which no odors can be detected. Some of the causes of olfaction problems are allergies, nasal polyps, viral infections and head trauma. In 2012 an estimated 9.8 million people aged 40 and older in the United States had hyposmia and an additional 3.4 million had anosmia/severe hyposmia. Hyposmia might be a very early sign of Parkinson's disease.Factor, Stewart A., & Weiner, William J., eds. (2008). ''Parkinson's Disease: Diagnosis and Clinical Management'', 2nd ed., pp. 72-73. New York: Demos Medical Publishing. Hyposmia is also an early and almost universal finding in Alzheimer's disease and dementia with Lewy bodies. Lifelong hyposmia could be caused by or comorbid with Kallmann syndrome or autism. Along with other chemosensory disturbances, hyposmia can be a key indicator of COVID-19. Epidemiology The National Health and Nutrition Examination Survey ( NHANES) collect ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phantosmia
Phantosmia (phantom smell), also called an olfactory hallucination or a phantom odor, is smelling an odor that is not actually there. This hallucination is intrinsically suspicious as the formal evaluation and detection of relatively low levels of odour particles is itself a very tricky task in air epistemology. It can occur in one nostril or both. Unpleasant phantosmia, cacosmia, is more common and is often described as smelling something that is burned, foul, spoiled, or rotten. Experiencing occasional phantom smells is normal and usually goes away on its own in time. When hallucinations of this type do not seem to go away or when they keep coming back, it can be very upsetting and can disrupt an individual's quality of life. Olfactory hallucinations can be caused by common medical conditions such as nasal infections, nasal polyps, or dental problems. It can result from neurological conditions such as migraines, head injuries, strokes, Parkinson's disease, seizures, or brain tu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Butyrophenones
Butyrophenone is an organic compound with the formula C6H5C(O)C3H7. It is a colorless liquid. The butyrophenone structure—a ketone flanked by a phenyl ring and a butyl chain—forms the basis for many other chemicals containing various substituents. Some of these butyrophenones are used to treat various psychiatric disorders such as schizophrenia, as well as acting as antiemetics. Examples of butyrophenone-derived pharmaceuticals include: * Benperidol‡‡ denotes drugs that are no longer (or were never to begin with) marketed in the United States. Some antipsychotics are not firmly placed in either first-generation or second-generation classes. (200 times more potent than chlorpromazine) * Bromperidol†† indicates drugs that are no longer (or were never) marketed in English-speaking countries. * Droperidol‡, Antiemetic for postoperative nausea and vomiting * Haloperidol, the most widely used classical antipsychotic drug in this class * Lumateperone, an atypical antip ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thioridazine Hydrochloride
Thioridazine (Mellaril or Melleril) is a first generation antipsychotic drug belonging to the phenothiazine drug group and was previously widely used in the treatment of schizophrenia and psychosis. The branded product was withdrawn worldwide in 2005 because it caused severe cardiac arrhythmias. However, generic versions are still available in the US. Indications Thioridazine was voluntarily discontinued by its manufacturer, Novartis, worldwide because it caused severe cardiac arrhythmias. However, generics remain on the market in some countries. Its primary use in medicine is for the treatment of schizophrenia. It was also tried with some success as a treatment for various psychiatric symptoms seen in people with dementia, but chronic use of thioridazine and other anti-psychotics in people with dementia is not recommended. Generic forms of thioridazine remain on the market in a few countries, usually with restrictions due to the risk of arrhythmias. For example, in the US, i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oliver Sacks
Oliver Wolf Sacks (9 July 1933 – 30 August 2015) was a British neurology, neurologist, Natural history, naturalist, historian of science, and writer. Born in London, Sacks received his medical degree in 1958 from The Queen's College, Oxford, before moving to the United States, where he spent most of his career. He interned at UCSF Medical Center, Mount Zion Hospital in San Francisco and completed his residency in neurology and neuropathology at the University of California, Los Angeles (UCLA). Later, he served as neurologist at Beth Abraham Hospital's chronic-care facility in the Bronx, where he worked with a group of survivors of the 1920s sleeping sickness encephalitis lethargica epidemic, who had been unable to move on their own for decades. His treatment of those patients became the basis of his 1973 book ''Awakenings (book), Awakenings'', which was adapted into an Academy Award-nominated Awakenings, feature film, in 1990, starring Robin Williams and Robert De Niro. His ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dopamine Antagonist
A dopamine antagonist, also known as an anti-dopaminergic and a dopamine receptor antagonist (DRA), is a type of drug which blocks dopamine receptors by receptor antagonism. Most antipsychotics are dopamine antagonists, and have been used in treating schizophrenia, bipolar disorder, and stimulant psychosis. Several other dopamine antagonists are antiemetics used in the treatment of nausea and vomiting. Receptor pharmacology Dopamine receptors are all G protein–coupled receptors, and are divided into two classes based on which G-protein they are coupled to. The D1-like class of dopamine receptors is coupled to Gαs/olf and stimulates adenylate cyclase production, whereas the D2-like class is coupled to Gαi/o and thus inhibits adenylate cyclase production. D1-like receptors: D1 and D5 D1-like receptors – D1 and D5 are always found post-synaptically. The genes coding these receptors lack introns, so there are no splice variants. D1 receptors * D1 receptors are found m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Threshold For Odor
The odor detection threshold is the lowest concentration of a certain odor compound that is perceivable by the human sense of smell. The threshold of a chemical compound is determined in part by its shape, polarity, partial charges, and molecular mass. The olfactory mechanisms responsible for a compound's different detection threshold is not well understood. As such, odor thresholds cannot be accurately predicted. Rather, they must be measured through extensive tests using human subjects in laboratory settings. Optical isomers can have different detection thresholds because their conformations may cause them to be less perceivable for the human nose. It is only in recent years that such compounds were separated on gas chromatographs. For raw water treatment and waste water management, the term commonly used is Threshold Odor Number (TON). For instance, the water to be supplied for domestic use in Illinois is 3 TON. Values * The threshold value is the concentration at which a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
