brainstem


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Related to brainstem: midbrain, pons, brainstem glioma

brainstem

 [brān´stem]
the stemlike portion of the brain connecting the cerebral hemispheres with the spinal cord, and comprising the pons, medulla oblongata, and midbrain; considered by some to include the diencephalon. Also written brain stem.

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

or

brain stem

(brān′stĕm′)
n.
The portion of the brain, consisting of the medulla oblongata, pons Varolii, and midbrain, that connects the spinal cord to the forebrain and cerebrum.

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.

brainstem

(brān′stĕm″)
Enlarge picture
BRAINSTEM
The stemlike part of the brain that connects the cerebral hemispheres with the spinal cord. It includes the diencephalin, midbrain, and hindbrain. Some anatomists do not include the diencephalon in the brainstem. See: illustration

brainstem

The part of the brain consisting of the medulla oblongata and pons, which connects the main brain (cerebrum) to the spinal cord. The brainstem contains the ‘vital centres’ for respiration and heart-beat and the nuclei of most of the CRANIAL NERVES as well as massive motor and sensory nerve trunks passing to and from the cord.

Brainstem

Brain structure closest to the spinal cord, involved in controlling vital functions, movement, sensation, and nerves supplying the head and neck.

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.
References in periodicals archive ?
Dos Santos, "Auditory Brainstem evoked response: response patterns of full-term and premature infants," Brazilian Journal of Otorhinolaryngology, vol.
Effect of Pioglitazone on PPAR[gamma] Expression in the Left Ventricle and Brainstem. In the brainstem of the PIO-treated animals, we observed a significant increase in mRNA encoding PPAR[gamma].
The auditory brainstem implant procedure is said to be the only effective sensory prosthetic for direct brain stimulation in cases that do not benefit from traditional methods like hearing aids or cochlear implants (CI).
Because the brainstem represents stimulus frequency differences occurring above 2000 Hz (the upper limits of brainstem phase locking) through timing [26] and phase representation [27, 28], the phase difference between two waveforms (in radians) can be converted to timing differences and represented in a "phaseogram." This analysis provides an objective measure of the response timing on a frequency-specific basis.
Hearing loss in patients with MS disease may be caused by plaques that are placed on the brainstem, any area of the entrance of the cochlear nerve into the brainstem, and the auditory cortex [6].
However, brainstem glioma was the second most common histological type (17.6%), which diverges from a classic study on the subject, which shows the medulloblastoma in the second position.
The same was true for the GCS-M in predicting poor prognosis for patients with brainstem or cerebella lesions, and the cutoff points were 4 or 5 (specificity 60-73% and sensitivity 78-91%).
cochlear implants and auditory brainstem implants) can restore hearing sensation through by-passing the ear structure and providing electric stimulation with tiny electrodes.
Of the patients with presumed brainstem ischemia underlying their INO, a demonstrable lesion on MRI is not found in almost 50% of the cases (5), while another report showed that only four out of 34 patients did not have a lesion (6).
ACHS, in contrast, usually results from brainstem lesions or insults affecting the medullary centers that control respiratory drive [3, 7, 8].