brain stem


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stem

 [stem]
a stalklike supporting structure; see also peduncle.
brain stem brainstem.

brain·stem

, brain stem (brān'stem), [TA]
Originally, the entire unpaired subdivision of the brain, composed of (in anterior sequence) the rhombencephalon, mesencephalon, and diencephalon as distinguished from the brain's only paired subdivision, the telencephalon. More recently, the term's connotation has undergone several arbitrary modifications: some use it to denote no more than rhombencephalon plus mesencephalon, distinguishing that complex from the prosencephalon (diencephalon plus telencephalon); others restrict it even further to refer exclusively to the rhombencephalon. From both developmental and architectural viewpoints, the original interpretation seems preferable.
Synonym(s): truncus encephali [TA]

brainstem

The central stalk-like axis of the lower CNS, which connects the brain with the spinal cord.
 
Components
• Medulla oblongata;
• Pons;
• Midbrain;
• Diencephalon.
 
Functions
• Transmission and “lower cortical” processing of sensory neural impulses from the periphery and motor impulses to muscles and other effectors;
• Anatomic site of egress of cranial nerves 3 to 12;
• Reticular functions, integrating cardiorespiratory control, arousal and alertness, consciousness.

brain·stem

, brain stem (brān'stem) [TA]
Originally, the entire unpaired subdivision of the brain, composed of the rhombencephalon, mesencephalon, and diencephalon as distinguished from the brain's only paired subdivision, the telencephalon. More recently, the connotation of the term has undergone several arbitrary modifications: some use it to denote no more than rhombencephalon plus mesencephalon, distinguishing that complex from the prosencephalon (diencephalon plus telencephalon); others restrict it even further to refer exclusively to the rhombencephalon. From both developmental and architectural viewpoints, the original interpretation seems preferable.

brain stem

that part of the brain in vertebrates which excludes the CEREBELLUM and CEREBRAL HEMISPHERES.

brain·stem

, brain stem (brān'stem) [TA]
Originally, the entire unpaired subdivision of the brain, composed of the rhombencephalon, mesencephalon, and diencephalon as distinguished from the brain's only paired subdivision, the telencephalon. More recently, the connotation of the term has undergone several arbitrary modifications: some use it to denote no more than rhombencephalon plus mesencephalon, distinguishing that complex from the prosencephalon (diencephalon plus telencephalon); others restrict it even further to refer exclusively to the rhombencephalon. From both developmental and architectural viewpoints, the original interpretation seems preferable.

stem

stalk; a stalklike supporting structure.

brain stem
References in periodicals archive ?
That's when the 5-cm tumour was discovered near my brain stem.
Ruby recently finished 30 treatments at Newcastle's Freeman Hospital after a brain stem tumour returned for a third time - despite proton therapy in the USA.
They showed that activity in some brain areas, such as the brain stem, begins to rise before the actual onset of the hot flash.
Stephanie Erlich, deputy county coroner, testified she had not inspected the brain stem and ``wouldn't have seen anything anyway,'' according to the opinion.
Slowed breathing: Heroin acts on the brain stem to slow Breathing--sometimes so much that the user stops breathing and dies.
In addition, in our patient, the disseminated encephalomyelitis involved parietooccipital, temporal, and frontal regions of the brain and also reached the brain stem.
THE BRAIN STEM controls basic bodily functions, like heartbeat and breathing.
Based on the cause of the injuries, current technology, and dialogues dealing with the injuries, the findings are clear: the forces applied to the head, neck, brain, and brain stem in Situation One and Three are believed to be far beyond the capability of any feasible helmet.
Glasky showed data from experiments demonstrating a statistically significant increase of 32 percent in brain stem cells in the hippocampus of mice, an area of the brain associated with memory.
The only solution was to surgically implant a series of electrodes directly into hearing nerves on Rachel's brain stem.
It would therefore appear to be incumbent on Catholic institutions engaged in organ transplantation to publish in detail precisely what criteria of complete and irreversible activity in the cerebrum, cerebellum, and brain stem, they use in determining the death of a donor.
Cory, pictured with his dad Steven, was diagnosed with a severe malignant tumour the size of a plum around his brain stem in 2011 and since then has battled through intensive chemotherapy and radiotherapy.