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Mesocortical Pathway
The mesocortical pathway is a dopaminergic pathway that connects the ventral tegmentum to the prefrontal cortex. It is one of the four major dopamine pathways in the brain. It is essential to the normal cognitive function of the dorsolateral prefrontal cortex (part of the frontal lobe), and is thought to be involved in cognitive control, motivation, and emotional response. This pathway may be the brain system that is abnormal or functioning abnormally in psychoses, such as schizophrenia.Diaz, Jaime. How Drugs Influence Behavior. Englewood Cliffs: Prentice Hall, 1996. It is thought to be associated with the negative symptoms of schizophrenia, which include avolition, alogia and flat affect. This pathway is closely associated with the mesolimbic pathway, which is also known as the mesolimbic reward pathway. Other dopamine pathways Other major dopamine pathways include: * mesolimbic pathway * nigrostriatal pathway * tuberoinfundibular pathway See also * Dopamine * Schizophrenia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesocortical Pathway
The mesocortical pathway is a dopaminergic pathway that connects the ventral tegmentum to the prefrontal cortex. It is one of the four major dopamine pathways in the brain. It is essential to the normal cognitive function of the dorsolateral prefrontal cortex (part of the frontal lobe), and is thought to be involved in cognitive control, motivation, and emotional response. This pathway may be the brain system that is abnormal or functioning abnormally in psychoses, such as schizophrenia.Diaz, Jaime. How Drugs Influence Behavior. Englewood Cliffs: Prentice Hall, 1996. It is thought to be associated with the negative symptoms of schizophrenia, which include avolition, alogia and flat affect. This pathway is closely associated with the mesolimbic pathway, which is also known as the mesolimbic reward pathway. Other dopamine pathways Other major dopamine pathways include: * mesolimbic pathway * nigrostriatal pathway * tuberoinfundibular pathway See also * Dopamine * Schizophrenia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Schizophrenia
Schizophrenia is a mental disorder characterized by continuous or relapsing episodes of psychosis. Major symptoms include hallucinations (typically hearing voices), delusions, and disorganized thinking. Other symptoms include social withdrawal, decreased emotional expression, and apathy. Symptoms typically develop gradually, begin during young adulthood, and in many cases never become resolved. There is no objective diagnostic test; diagnosis is based on observed behavior, a history that includes the person's reported experiences, and reports of others familiar with the person. To be diagnosed with schizophrenia, symptoms and functional impairment need to be present for six months (DSM-5) or one month (ICD-11). Many people with schizophrenia have other mental disorders, especially substance use disorders, depressive disorders, anxiety disorders, and obsessive–compulsive disorder. About 0.3% to 0.7% of people are diagnosed with schizophrenia during their lifetime. In 2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Schizophrenia
Schizophrenia is a mental disorder characterized by continuous or relapsing episodes of psychosis. Major symptoms include hallucinations (typically hearing voices), delusions, and disorganized thinking. Other symptoms include social withdrawal, decreased emotional expression, and apathy. Symptoms typically develop gradually, begin during young adulthood, and in many cases never become resolved. There is no objective diagnostic test; diagnosis is based on observed behavior, a history that includes the person's reported experiences, and reports of others familiar with the person. To be diagnosed with schizophrenia, symptoms and functional impairment need to be present for six months (DSM-5) or one month (ICD-11). Many people with schizophrenia have other mental disorders, especially substance use disorders, depressive disorders, anxiety disorders, and obsessive–compulsive disorder. About 0.3% to 0.7% of people are diagnosed with schizophrenia during their lifetime. In 2 ... [...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 compound, organic chemical of the catecholamine and phenethylamine families. Dopamine constitutes about 80% of the catecholamine content in the brain. It is an amine synthesized by removing a carboxyl group from a molecule of its precursor (chemistry), precursor chemical, L-DOPA, which is biosynthesis, 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. Neurotransmitters are synthesized in specific regions of the brain, but affect many regions systemically. The brain includes several distinct dopaminergic pathway, dopamine pathways, one of which plays a major role in the motivational component of reward system, reward-motivated behavior. The anticipa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tuberoinfundibular Pathway
The tuberoinfundibular pathway refers to a population of dopamine neurons that project from the arcuate nucleus ( the "infundibular nucleus") in the tuberal region of the hypothalamus to the median eminence. It is one of the four major dopamine pathways in the brain. Dopamine released at this site inhibits the secretion of prolactin from anterior pituitary gland lactotrophs by binding to D2 receptors. Some antipsychotic drugs block dopamine in the tuberoinfundibular pathway, which can cause an increase in the amount of prolactin in the blood (hyperprolactinemia). Other dopamine pathways Other major dopamine pathways include: * Mesocortical pathway * Mesolimbic pathway * Nigrostriatal pathway See also * Antipsychotic * Dopamine Dopamine (DA, a contraction of 3,4-dihydroxyphenethylamine) is a neuromodulatory molecule that plays several important roles in cells. It is an organic compound, organic chemical of the catecholamine and phenethylamine families. Dopamine const ... ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nigrostriatal Pathway
The nigrostriatal pathway is a bilateral dopaminergic pathway in the brain that connects the substantia nigra pars compacta (SNc) in the midbrain with the dorsal striatum (i.e., the caudate nucleus and putamen) in the forebrain. It is one of the four major dopamine pathways in the brain, and is critical in the production of movement as part of a system called the basal ganglia motor loop. Dopaminergic neurons of this pathway release dopamine from axon terminals that synapse onto GABAergic medium spiny neurons (MSNs), also known as spiny projection neurons (SPNs), located in the striatum. Degeneration of dopaminergic neurons in the SNc is one of the main pathological features of Parkinson's disease, leading to a marked reduction in dopamine function and the symptomatic motor deficits of Parkinson's disease including hypokinesia, tremors, rigidity, and postural imbalance. Anatomy The connection between the substantia nigra pars compacta and the dorsal striatum is mediated via dopa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesolimbic Pathway
The mesolimbic pathway, sometimes referred to as the reward pathway, is a dopaminergic pathway in the brain. The pathway connects the ventral tegmental area in the midbrain to the ventral striatum of the basal ganglia in the forebrain. The ventral striatum includes the nucleus accumbens and the olfactory tubercle. The release of dopamine from the mesolimbic pathway into the nucleus accumbens regulates incentive salience (e.g. motivation and desire for rewarding stimuli) and facilitates reinforcement and reward-related motor function learning; it may also play a role in the subjective perception of pleasure. The dysregulation of the mesolimbic pathway and its output neurons in the nucleus accumbens plays a significant role in the development and maintenance of an addiction. Anatomy The mesolimbic pathway is a collection of dopaminergic (i.e., dopamine-releasing) neurons that project from the ventral tegmental area (VTA) to the ventral striatum, which includes the nucleus accumben ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flat Affect
Reduced affect display, sometimes referred to as emotional blunting or emotional numbing, is a condition of reduced emotional reactivity in an individual. It manifests as a failure to express feelings ( affect display) either verbally or nonverbally, especially when talking about issues that would normally be expected to engage the emotions. Expressive gestures are rare and there is little animation in facial expression or vocal inflection. Reduced affect can be symptomatic of autism, schizophrenia, depression, posttraumatic stress disorder, depersonalization disorder, schizoid personality disorder or brain damage. It may also be a side effect of certain medications (e.g., antipsychotics and antidepressants). Reduced affect should be distinguished from apathy and anhedonia, which explicitly refer to a lack of emotion, whereas reduced affect is a lack of emotional expression (affect display) regardless of whether emotion (underlying affect) is actually reduced or not. Types ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alogia
In psychology, alogia (; from Greek ἀ-, "without", and λόγος, "speech" + New Latin -ia) is poor thinking inferred from speech and language usage. "alogia An impoverishment in thinking that is inferred from observing speech and language behavior. There may be brief and concrete replies to questions and restriction in the amount of spontaneous speech (termed poverty of speech). Sometimes the speech is adequate in amount but conveys little information because it is overconcrete, overabstract, repetitive, or stereotyped (termed poverty of content)." There may be a general lack of additional, unprompted content seen in normal speech, so replies to questions may be brief and concrete, with less spontaneous speech. This is termed poverty of speech or laconic speech. "laconic speech Condition characterized by a reduction in the quantity of spontaneous speech; replies to questions are brief and unelaborated, and little or no unprompted additional information is provided. Occurs in ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Avolition
Avolition, as a symptom of various forms of psychopathology, is the decrease in the ability to initiate and persist in self-directed purposeful activities. Such activities that appear to be neglected usually include routine activities, including hobbies, going to work and/or school, and most notably, engaging in social activities. A person experiencing avolition may stay at home for long periods of time, rather than seeking out work or peer relations. Psychopathology People with avolition often want to complete certain tasks but lack the ability to initiate behaviours necessary to complete them. Avolition is most commonly seen as a symptom of some other disorder, but might be considered a primary clinical disturbance of itself (or as a coexisting second disorder) related to disorders of diminished motivation. In 2006, avolition was identified as a negative symptom of schizophrenia by the National Institute of Mental Health (NIMH), and has been observed in patients with bipolar d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Psychosis
Psychosis is a condition of the mind that results in difficulties determining what is real and what is not real. Symptoms may include delusions and hallucinations, among other features. Additional symptoms are incoherent speech and behavior that is inappropriate for a given situation. There may also be sleep problems, social withdrawal, lack of motivation, and difficulties carrying out daily activities. Psychosis can have serious adverse outcomes. As with many psychiatric phenomena, psychosis has several different causes. These include mental illness, such as schizophrenia or schizoaffective disorder, bipolar disorder, sensory deprivation and in rare cases, major depression (psychotic depression). Other causes include: trauma, sleep deprivation, some medical conditions, certain medications, and drugs such as cannabis, hallucinogens, and stimulants. One type, known as postpartum psychosis, can occur after giving birth. The neurotransmitter dopamine is believed to p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dopaminergic Pathway
Dopaminergic pathways (dopamine pathways, dopaminergic projections) in the human brain are involved in both physiological and behavioral processes including movement, cognition, executive functions, reward, motivation, and neuroendocrine control. Each pathway is a set of projection neurons, consisting of individual dopaminergic neurons. The four major dopaminergic pathways are the mesolimbic pathway, the mesocortical pathway, the nigrostriatal pathway, and the tuberoinfundibular pathway.The mesolimbic pathway and the mesocortical pathway form the mesocorticolimbic system. Two other dopaminergic pathways to be considered are the hypothalamospinal tract and the incertohypothalamic pathway. Parkinson's disease, attention deficit hyperactivity disorder (ADHD), substance use disorders (addiction), and restless legs syndrome (RLS) can be attributed to dysfunction in specific dopaminergic pathways. The dopamine neurons of the dopaminergic pathways synthesize and release the neurotr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
