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brain

   Also found in: Dictionary/thesaurus, Legal, Acronyms, Idioms, Encyclopedia, Wikipedia, Hutchinson 0.01 sec.
brain (brān) encephalon; that part of the central nervous system contained within the cranium, comprising the prosencephalon (forebrain), mesencephalon (midbrain), and rhombencephalon (hindbrain); it develops from the anterior part of the embryonic neural tube. See also cerebrum.
split brain  one in which the connections between the hemispheres have been disrupted or severed; used to provide access to the third ventricle or to control epilepsy.

brain (brn)
n.
The portion of the central nervous system that is enclosed within the cranium, continuous with the spinal cord, and composed of gray matter and white matter. It is the primary center for the regulation and control of bodily activities, receiving and interpreting sensory impulses, and transmitting information to the muscles and body organs. It is also the seat of consciousness, thought, memory, and emotion. Also called encephalon.
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brain
cross section

brain
Etymology: AS, bragen
the portion of the central nervous system contained within the cranium. It consists principally of the cerebrum, thalamus, hypothalamus, cerebellum, midbrain, pons, and medulla. Specialized cells in its mass of convoluted, soft gray or white tissue coordinate and regulate the functions of the central nervous system, integrating the functions of the body as a whole.

brain
encephalon; that part of the central nervous system contained within the cranium, comprising the forebrain, midbrain and hindbrain, and developed from the embryonic neural tube. It is connected at its base with the spinal cord. The brain is a mass of soft, pinkish gray nerve tissue. For specific brain diseases see under headings relating to etiology and lesion.

brain abscess
common signs caused by an abscess in the brain are circling, rotation of the head, abnormal reflexes in one eye. The CSF may show evidence of infection.
brain aneurysm
see berry aneurysm.
brain anoxia
acute or chronic insufficiency of the blood supply to the brain causes anoxia which causes clinical signs that vary with the severity of the deprivation. Acute anoxia causes muscle tremor, recumbency, convulsions and death or recovery if the anoxia is relieved soon enough. Chronic anoxia causes lethargy, weakness, blindness and sometimes convulsions. In either case there may be permanent damage.
brain case
the cranium.
brain cestodal cyst
brain coup lesion
a derivation from contrecoup.
brain dead
irreversible coma with apnea, loss of all brainstem reflexes and absence of activity on an electroencephalogram.
brain decompression
relieving the pressure within the cranial vault. This may be done surgically by opening the cranium, or medically by administering hypertonic solutions of slowly metabolized materials, such as mannitol, intravenously.
brain edema
an important part of a number of acute diseases, e.g. lead poisoning, encephalitis, salt poisoning in swine, polioencephalomalacia of ruminants and hypoxia due to any cause. Clinically manifested by blindness, opisthotonos, nystagmus, recumbency and tonic convulsions. Inherited in polled and horned Herefords; calves are recumbent at birth and are never able to stand but consciousness is normal. See also neuraxial edema.
brain ependymal lining
brain hematoma
may occur with trauma, in extradural, subdural or intraparenchymal locations. They can cause progressive increase in intracranial pressure and eventually death.
brain hemorrhage
intracranial hemorrhage affecting the brain usually follows traumatic injury but spontaneous hemorrhage may result from an intrinsic vascular lesion. Loss of consciousness is a common sign followed by residual signs depending on the locality and size of the hemorrhage. Ataxia and convulsions are common sequelae.
brain herniation
displacement of brain from the cranial vault through the foramina (tentorial notch or foramen magnum) or ventral to dural septae. The usual causes are brain edema or hemorrhage with resulting increase in intracranial pressure.
brain hypoxia
see brain anoxia (above).
brain infarction
see feline ischemic encephalopathy.
brain ischemia
see brain anoxia (above).
brain laceration
occurs in cranial trauma that fractures the skull, causes severe acceleration or deceleration, or penetrates the skull and brain tissue.
brain necrosis
brain pigmentation
occurs in phalaris spp. poisoning; a characteristic greenish brown color grossly of the gray matter in brainstem nuclei and spinal cord, caused by a suspected lysosomal storage of granules of pigment material; usually associated with some degree of Wallerian degeneration within spinal cord tracts.
brain sand
brain scanning
a radiographic, magnetic or nuclear medical procedure for the detection of brain tumors, abscesses, hematomas and other intracranial lesions. Not widely used in veterinary medicine because of the expensive equipment required.
brain spongy degeneration
brain staggers
see dummy.
brain trauma
injury to the brain, including that caused by migrating worm larvae, will have diffuse effects including the development of edema, and local effects due to pressure by displaced bone or to hemorrhage. Initial shock, manifested as unconsciousness, is likely to be followed by residual localizing signs, e.g. facial paralysis, head rotation.
brain tumors
cause signs suggestive of local space-occupying lesion in the cranial cavity, including the increased intracranial pressure syndrome, blindness with disturbance of ocular reflexes, head rotation, circling and jacksonian epileptic episodes.
brain ventricles
see third, fourth, fifth ventricle.

Patient discussion about brain.

Q. Could I be going through a Brain aneurysm? i woke up in the night with a bad headache in the back of my head and above my eye. never had a headache like that. but all day today have not had the headache. could this be an aneurysm?

A. An Aneurysm is when a blood vessel just pops out in you’re brain. Very ironically, there are no sensory nerves inside the brain and the headache that comes with aneurysm is when the brain starts pressuring the material that surrounds it. That means this will be a later symptoms and you’ll probably have a paralyses before, or have problem speaking and things like that. If you are not convinced – you can go to the hospital and ask for a scan.

Q. can anyone tell me why i am having brain pain that i have never had before. i have been having severe pain far worse than a migraine headache in my forehead and eyes and the worse of the pain is on top of my head in my brain and the back of my head in the brain area.i have had this pain and other symptoms now for about 2 weeks and seem to get worse as each day passes. getting real had to sleep with the pain getting to intense. also with it i have been having stomach pains in my right side and ringing in both of my ears off and on.chest pain even though my chest is completely clear. anyone have any suggestions on what it could be would be really appreciated. thank you

A. GO SEE A DOCTOR...SOON...THE SYMTOMS YOU SAY YOU HAVE COULD BE SERIOUS IN NATURE...mrfoot56

Q. What damage does depression do to the brain and how can you treat it? How does it affect your chemical balance, your brain? Is it critical or will be critical later in life? I just read on Yahoo News that Clinical stress could increase risk of Alzheimer's later in life. Does age matter like during teen years? I had depression and begun running. I noticed that I have a hard time focusing and absorbing information. I forgot a lot of things. All my brain seems to focus on is emotions. Can I change that? The running has made me feel a lot better afterwards

A. What you describe is considered as an attention disorder. But it’s very understandable while being on a depression episode. If it’s not on a depression episode- then it was strange… I suffer from depression for the last 12 years and I’m not sure I saw a real change in my cognitive abilities. But I’m not so sure…good idea about the running! it releases Endorphins which elevate mood.

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