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Prepulse Inhibition
Prepulse inhibition (PPI) is a neurological phenomenon in which a weaker prestimulus (prepulse) inhibits the reaction of an organism to a subsequent strong reflex-eliciting stimulus (pulse), often using the startle reflex. The stimuli are usually acoustic, but tactile stimuli (e.g. via air puffs onto the skin) and light stimuli are also used. When prepulse inhibition is high, the corresponding one-time startle response is reduced. The reduction of the amplitude of startle reflects the ability of the nervous system to temporarily adapt to a strong sensory stimulus when a preceding weaker signal is given to warn the organism. PPI is detected in numerous species including mice and humans. Although the extent of the adaptation affects numerous systems, the most comfortable to measure are the muscular reactions, which are normally diminished as a result of the nervous inhibition. Deficits of prepulse inhibition manifest in the inability to filter out the unnecessary information; they h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Panic Disorder
Panic disorder is a mental disorder, specifically an anxiety disorder, characterized by reoccurring unexpected panic attacks. Panic attacks are sudden periods of intense fear that may include palpitations, sweating, shaking, shortness of breath, numbness, or a sense of impending doom. The maximum degree of symptoms occurs within minutes. There may be ongoing worries about having further attacks and avoidance of places where attacks have occurred in the past. The exact cause of panic disorder is not fully understood, however there are a number of factors linked to the disorder such as a stressful or traumatic life event, having close family members with the disorder and an imbalance of neurotransmitters. Diagnosis involves ruling out other potential causes of anxiety including other mental disorders, medical conditions such as heart disease or hyperthyroidism, and drug use. Screening for the condition may be done using a questionnaire. Panic disorder is usually treated with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CHRFAM7A
CHRNA7-FAM7A fusion protein is a protein that in humans is encoded by the ''CHRFAM7A'' gene. The nicotinic acetylcholine receptors Nicotinic acetylcholine receptors, or nAChRs, are receptor polypeptides that respond to the neurotransmitter acetylcholine. Nicotinic receptors also respond to drugs such as the agonist nicotine. They are found in the central and peripheral ner ... (nAChRs) are members of a superfamily of ligand-gated ion channels that mediate fast signal transmission at synapses. The family member CHRNA7, which is located on chromosome 15 in a region associated with several neuropsychiatric disorders, is partially duplicated and forms a hybrid with a novel gene from the family with sequence similarity 7 (FAM7A). Alternative splicing has been observed, and two variants exist, for this hybrid gene. The N-terminally truncated products predicted by the largest open reading frames for each variant would lack the majority of the neurotransmitter-gated ion-channel ligan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CHRNA7
Neuronal acetylcholine receptor subunit alpha-7, also known as nAChRα7, is a protein that in humans is encoded by the ''CHRNA7'' gene. The protein encoded by this gene is a subunit of certain nicotinic acetylcholine receptors (nAchR). Function The nicotinic acetylcholine receptors (nAChRs) are members of a superfamily of ligand-gated ion channels that mediate fast signal transmission at synapses. The nAChRs are thought to be hetero-pentamers composed of homologous subunits. The proposed structure for each subunit is a conserved N-terminal extracellular domain followed by three conserved transmembrane domains, a variable cytoplasmic loop, a fourth conserved transmembrane domain, and a short C-terminal extracellular region. The protein encoded by this gene forms a homo-oligomeric channel, displays marked permeability to calcium ions and is a major component of brain nicotinic receptors that are blocked by, and highly sensitive to, alpha-bungarotoxin. Once this receptor binds ac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Schizophrenia And Smoking
Schizophrenia and tobacco smoking have been historically associated. Smoking is known to harm the health of people with schizophrenia. Studies across 20 countries showed that people with schizophrenia were much more likely to smoke than those without this diagnosis. For example, in the United States, 90% or more of people with schizophrenia smoked, compared to 20% of the general population in 2006. It is well established that smoking is more prevalent among people with schizophrenia than the general population as well as those with other psychiatric diagnoses. There is currently no definitive explanation for this difference. Many social, psychological, and biological explanations have been proposed, but today research focuses on neurobiology. One important reason people smoke cigarettes is due to finding it enjoyable. However, increased rates of smoking among people with schizophrenia have a number of serious impacts, including increased rates of mortality, increased risks of su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dopamine Hypothesis Of Schizophrenia
The dopamine hypothesis of schizophrenia or the dopamine hypothesis of psychosis is a model that attributes the positive symptoms of schizophrenia to a disturbed and hyperactive dopaminergic signal transduction. The model draws evidence from the observation that a large number of antipsychotics have dopamine-receptor antagonistic effects. The theory, however, does not posit dopamine overabundance as a complete explanation for schizophrenia. Rather, the overactivation of D2 receptors, specifically, is one effect of the global chemical synaptic dysregulation observed in this disorder. Introduction Some researchers have suggested that dopamine systems in the mesolimbic pathway may contribute to the 'positive symptoms' of schizophrenia, whereas problems concerning dopamine function within the mesocortical pathway may be responsible for the 'negative symptoms', such as avolition and alogia. Abnormal expression, thus distribution of the D2 receptor between these areas and the rest o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dopamine
Dopamine (DA, a contraction of 3,4-dihydroxyphenethylamine) is a neuromodulatory molecule that plays several important roles in cells. It is an organic chemical of the catecholamine and phenethylamine families. It is an amine synthesized by removing a carboxyl group from a molecule of its precursor chemical, L-DOPA, which is synthesized in the brain and kidneys. Dopamine is also synthesized in plants and most animals. In the brain, dopamine functions as a neurotransmitter—a chemical released by neurons (nerve cells) to send signals to other nerve cells. The brain includes several distinct dopamine pathways, one of which plays a major role in the motivational component of reward-motivated behavior. The anticipation of most types of rewards increases the level of dopamine in the brain, and many addictive drugs increase dopamine release or block its reuptake into neurons following release. Other brain dopamine pathways are involved in motor control and in controllin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Psychosis
In psychopathology, psychosis is a condition in which a person is unable to distinguish, in their experience of life, between what is and is not real. Examples of psychotic symptoms are delusions, hallucinations, and disorganized or incoherent thoughts or speech. Psychosis is a description of a person's state or symptoms, rather than a particular mental illness, and it is not related to psychopathy (a personality construct characterized by impaired empathy and remorse, along with bold, disinhibited, and egocentric traits). Common causes of chronic (i.e. ongoing or repeating) psychosis include schizophrenia or schizoaffective disorder, bipolar disorder, and brain damage (usually as a result of alcoholism). Acute (temporary) psychosis can also be caused by severe distress, sleep deprivation, sensory deprivation, some medications, and drug use (including alcohol, cannabis, hallucinogens, and stimulants). Acute psychosis is termed primary if it results from a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Temporal Lobe Epilepsy
In the field of neurology, temporal lobe epilepsy is an enduring brain disorder that causes unprovoked seizures from the temporal lobe. Temporal lobe epilepsy is the most common type of focal onset epilepsy among adults. Seizure symptoms and behavior distinguish seizures arising from the mesial (medial) temporal lobe from seizures arising from the lateral (neocortical) temporal lobe. Memory and psychiatric comorbidities may occur. Diagnosis relies on electroencephalographic (EEG) and neuroimaging studies. Anticonvulsant medications, epilepsy surgery, and dietary treatments may improve seizure control. Types Under the International League Against Epilepsy (ILAE) 2017 classification of the epilepsies, focal onset epilepsy occurs from seizures arising from a biological neural network within a single cerebral hemisphere. Temporal lobe epilepsy occurs from seizures arising within the temporal lobe. Temporal lobe epilepsy is the most common focal onset epilepsy, and 80% of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tourette's Syndrome
Tourette syndrome (TS), or simply Tourette's, is a common neurodevelopmental disorder that begins in childhood or adolescence. It is characterized by multiple movement (motor) tics and at least one vocal (phonic) tic. Common tics are blinking, coughing, throat clearing, sniffing, and facial movements. These are typically preceded by an unwanted urge or sensation in the affected muscles known as a premonitory urge, can sometimes be suppressed temporarily, and characteristically change in location, strength, and frequency. Tourette's is at the more severe end of a spectrum of tic disorders. The tics often go unnoticed by casual observers. Tourette's was once regarded as a rare and bizarre syndrome and has popularly been associated with coprolalia (the utterance of obscene words or socially inappropriate and derogatory remarks). It is no longer considered rare; about 1% of school-age children and adolescents are estimated to have Tourette's, though coprolalia occurs only in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Attention Deficit Disorder
Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterised by symptoms of inattention, hyperactivity, impulsivity, and emotional dysregulation that are excessive and pervasive, impairing in multiple contexts, and Developmental psychology, developmentally inappropriate. ADHD symptoms arise from executive dysfunction. Impairments resulting from deficits in self-regulation such as time management, Cognitive inhibition, inhibition, task initiation, and sustained attention can include poor professional performance, relationship difficulties, and numerous health risks, collectively predisposing to a diminished Quality of life (healthcare), quality of life and a reduction in life expectancy. As a consequence, the disorder costs society hundreds of billions of US dollars each year, worldwide. It is associated with other mental disorders as well as non-psychiatric disorders, which can cause additional impairment. While ADHD involves a lack of su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nocturnal Enuresis
Nocturnal enuresis (NE), also informally called bedwetting, is involuntary urination while asleep after the age at which bladder control usually begins. Bedwetting in children and adults can result in emotional stress. Complications can include urinary tract infections. Most bedwetting is a developmental delay—not an emotional problem or physical illness. Only a small percentage (5 to 10%) of bedwetting cases have a specific medical cause. Bedwetting is commonly associated with a family history of the condition. Nocturnal enuresis is considered ''primary'' when a child has not yet had a prolonged period of being dry. ''Secondary'' nocturnal enuresis is when a child or adult begins wetting again after having stayed dry. Treatments range from behavioral therapy, such as bedwetting alarms, to medication, such as hormone replacement, and even surgery such as urethral dilatation. Since most bedwetting is simply a developmental delay, most treatment plans aim to prote ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
