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Centromedian Nucleus
In the anatomy of the brain, the centromedian nucleus, also known as the centrum medianum, (CM or Cm-Pf) is a nucleus in the posterior group of the intralaminar thalamic nuclei (ITN) in the thalamus. (This must not be confused with the central medial nucleus, which is in the anterior group of the ITN.) There are two centromedian nuclei arranged bilaterally. In humans, each centromedian nucleus contains about 2200 neurons per cubic millimetre and has a volume of about 310 cubic millimetres with 664,000 neurons in total. It measures less than 10 millimetres in every dimension. It belongs to the caudal intralaminar group of thalamic nuclei and is situated within the medial thalamus. It is bordered superiorly by the mediodorsal nucleus, medially by the parafascicular nucleus, and posteriorly by the pulvinar. Input and output It sends nerve fibres to the subthalamic nucleus and putamen. It receives nerve fibres from the cerebral cortex, vestibular nuclei, globus pallidus, superior col ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intralaminar Thalamic Nuclei
The intralaminar thalamic nuclei (ITN) are collections of neurons in the medullary laminae of thalamus, internal medullary lamina of the thalamus.Mancall, E., Brock, D. & Gray, H. (2011). Gray's clinical neuroanatomy the anatomic basis for clinical neuroscience. Philadelphia: Elsevier/Saunders. Anatomy Structure The ITN are generally divided in two groups as follows: * anterior (rostral) group ** central lateral nucleus ** central medial nucleus (''not'' referred to as "centromedial") ** paracentral nucleus * posterior (caudal) intralaminar group ** centromedian nucleus ** parafascicular nucleus Some sources also include a "central dorsal" nucleus. Afferents Midline intralaminar nuclei receive afferents from the brain stem, spinal cord, and cerebellum. Connections with the cerebral cortex and basal nuclei are reciprocal. Afferents from the spinothalamic tract as well as periaqueductal gray are part of a pathway involved in pain processing. Efferents The intralaminar nucl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Absence Seizure
Absence seizures are one of several kinds of generalized seizures. Absence seizures are characterized by a brief loss and return of consciousness, generally not followed by a period of lethargy (i.e. without a notable postictal state). Absence seizures are most common in children. They affect both sides of the brain. In the past, absence epilepsy was referred to as "pyknolepsy," a term derived from the Greek word "pyknos," signifying "extremely frequent" or "grouped". These seizures are sometimes referred to as petit mal seizures (from the French for "little illness", a term dated to the late 18th century); however, usage of this terminology is no longer recommended. Childhood absence epilepsy represents a significant portion, accounting for approximately 10 to 17%, of all cases of childhood-onset epilepsy, establishing it as the most common form of pediatric epilepsy. This syndrome is characterized by daily occurrences of frequent but brief episodes of staring spells. These ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
California Institute Of Technology
The California Institute of Technology (branded as Caltech) is a private research university in Pasadena, California, United States. The university is responsible for many modern scientific advancements and is among a small group of institutes of technology in the United States that are devoted to the instruction of pure and applied sciences. The institution was founded as a preparatory and vocational school by Amos G. Throop in 1891 and began attracting influential scientists such as George Ellery Hale, Arthur Amos Noyes, and Robert Andrews Millikan in the early 20th century. The vocational and preparatory schools were disbanded and spun off in 1910, and the college assumed its present name in 1920. In 1934, Caltech was elected to the Association of American Universities, and the antecedents of NASA's Jet Propulsion Laboratory, which Caltech continues to manage and operate, were established between 1936 and 1943 under Theodore von Kármán. Caltech has six academic divisi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrodes
An electrode is an electrical conductor used to make contact with a nonmetallic part of a circuit (e.g. a semiconductor, an electrolyte, a vacuum or a gas). In electrochemical cells, electrodes are essential parts that can consist of a variety of materials (chemicals) depending on the type of cell. An electrode may be called either a cathode or anode according to the direction of the electric current, unrelated to the potential difference between electrodes. Michael Faraday coined the term "" in 1833; the word recalls the Greek ἤλεκτρον (, "amber") and ὁδός (, "path, way"). The electrophore, invented by Johan Wilcke in 1762, was an early version of an electrode used to study static electricity. Anode and cathode in electrochemical cells Electrodes are an essential part of any battery. The first electrochemical battery was devised by Alessandro Volta and was aptly named the Voltaic cell. This battery consisted of a stack of copper and zinc electrodes sep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hemispatial Neglect
Hemispatial neglect is a neuropsychological condition in which, after damage to one hemisphere of the brain (e.g. after a stroke), a deficit in attention and awareness towards the side of space opposite brain damage (contralesional space) is observed. It is defined by the inability of a person to process and perceive stimuli towards the contralesional side of the body or environment. Hemispatial neglect is very commonly contralateral to the damaged hemisphere, but instances of ipsilesional neglect (on the same side as the lesion) have been reported. Presentation Hemispatial neglect results most commonly from strokes and brain unilateral injury to the right cerebral hemisphere, with rates in the critical stage of up to 80% causing visual neglect of the left-hand side of space. Neglect is often produced by massive strokes in the middle cerebral artery region and is variegated, so that most sufferers do not exhibit all of the syndrome's traits. Right-sided spatial neglect is rare ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Delirium
Delirium (formerly acute confusional state, an ambiguous term that is now discouraged) is a specific state of acute confusion attributable to the direct physiological consequence of a medical condition, effects of a psychoactive substance, or multiple causes, which usually develops over the course of hours to days. As a syndrome, delirium presents with disturbances in attention, awareness, and higher-order cognition. People with delirium may experience other neuropsychiatric disturbances including changes in psychomotor activity (e.g., hyperactive, hypoactive, or mixed level of activity), disrupted sleep-wake cycle, emotional disturbances, disturbances of consciousness, or altered state of consciousness, as well as perceptual disturbances (e.g., hallucinations and delusions), although these features are not required for diagnosis. Diagnostically, delirium encompasses both the syndrome of acute confusion and its underlying organic process known as an acute encephalopathy. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mutism
In human development, muteness or mutism is defined as an absence of speech, with or without an ability to hear the speech of others. Mutism is typically understood as a person's inability to speak, and commonly observed by their family members, caregivers, teachers, doctors or speech and language pathologists. It may not be a permanent condition, as muteness can be caused or manifest due to several different phenomena, such as physiological injury, illness, medical side effects, psychological trauma, developmental disorders, or neurological disorders. A specific physical disability or communication disorder can be more easily diagnosed. Loss of previously normal speech (aphasia) can be due to accidents, disease, or surgical complication; it is rarely for psychological reasons. Treatment or management also varies by cause and this can often be determined after a speech assessment. Treatment can sometimes restore speech. If not, a range of assistive and augmentative communicati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Persistent Vegetative State
A vegetative state (VS) or post-coma unresponsiveness (PCU) is a disorder of consciousness in which patients with severe brain damage are in a state of partial arousal rather than true awareness. After four weeks in a vegetative state, the patient is classified as being in a persistent vegetative state (PVS). This diagnosis is classified as a permanent vegetative state some months (three in the US and six in the UK) after a non-traumatic brain injury or one year after a traumatic injury. The term unresponsive wakefulness syndrome may be used alternatively, as "vegetative state" has some negative connotations among the public. It is occasionally also called Apallic syndrome or Apallisches syndrome, Loanword, borrowings from German, primarily in European or older sources. Definition There are several definitions that vary by technical versus layman's usage. There are different legal implications in different countries. Medical definition Per the definition of the British Royal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coma
A coma is a deep state of prolonged unconsciousness in which a person cannot be awakened, fails to Nociception, respond normally to Pain, painful stimuli, light, or sound, lacks a normal Circadian rhythm, sleep-wake cycle and does not initiate voluntary actions. The person may experience respiratory and circulatory problems due to the body's inability to maintain normal bodily functions. People in a coma often require extensive medical care to maintain their health and prevent complications such as pneumonia or blood clots. Coma patients exhibit a complete absence of wakefulness and are unable to consciously feel, speak or move. Comas can be the result of natural causes, or can be Induced coma, medically induced, for example, during General anaesthesia, general anesthesia. Clinically, a coma can be defined as the consistent inability to follow a one-step command. For a patient to maintain consciousness, the components of ''wakefulness'' and ''awareness'' must be maintained. Wak ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brain Death
Brain death is the permanent, irreversible, and complete loss of Electroencephalography, brain function, which may include cessation of involuntary activity (e.g., Control of ventilation#Control of respiratory rhythm, breathing) necessary to sustain life. It differs from persistent vegetative state, in which the person is alive and some autonomic functions remain. It is also distinct from comas as long as some brain and bodily activity and function remain, and it is also not the same as the condition locked-in syndrome. A differential diagnosis can medically distinguish these differing conditions. Brain death is used as an indicator of legal death in many jurisdictions, but it is Medical definition of death, defined inconsistently and often confused by the public. Various parts of the brain may keep functioning when others do not anymore, bringing questions about whether they should truly be considered dead. The term "brain death" has been used to refer to various combinations. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
General Anaesthetic
General anaesthetics (or anesthetics) are often defined as compounds that induce a loss of consciousness in humans or loss of righting reflex in animals. Clinical definitions are also extended to include an induced coma that causes lack of awareness to painful stimuli, sufficient to facilitate surgical applications in clinical and veterinary practice. General anaesthetics do not act as analgesics and should also not be confused with sedatives. General anaesthetics are a structurally diverse group of compounds whose mechanisms encompass multiple biological targets involved in the control of neuronal pathways. The precise workings are the subject of some debate and ongoing research. General anesthetics elicit a state of General anaesthesia, general anesthesia. It remains somewhat controversial regarding how this state should be defined. General anesthetics, however, typically elicit several key reversible effects: immobility, analgesia, amnesia, unconsciousness, and reduced autonomi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tourette 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 disorder, 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 Tourette syndrome#Epidemiology, estimated to hav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
