Question

Anatomy Tutorial: the Brainstem - Medulla Oblongata, Pons, Midbrain

Answer 1

\({\bf{Basic~Functions:}}\) relays information between the brain and spinal cord. controls autonomic processes. divided into three groups of nuclei with various sub-functions.
1. relay stations/processing centers
> gracile nucleus + cuneate nucleus: carry information to thalamus
> solitary nucleus: receives information from CNS
> olivary nucleus: carry information from spinal cord, cerebral cortex, diencephalon, brainstem, to the cerebral cortex
2. nuclei of cranial nerves
3. autonomic nuclei
> reflex centers: take info from cranial nerves, cerebral cortex, diancephalon, brainstem, and control output in the cardiovascular and respiratory rhythmicity centers

Answer 2

\({\bf{Pons:}}\)
- extends from the medulla oblongata to mesencephalon
- separated from the cerebellum by the 4th ventricle
- attached to cerebellum via cerebellar peduncles
like the medulla, also contains various nuclei groups
> sensory and motor nuclei for cranial nerves
> nuclei for respiratory centers that act on the respiratory rhythmicity center in the medulla oblongata
> ascending, descending, transverse tracts; allow information to be transmitted between cerebellum hemispheres

Answer 3

\({\bf{Midbrain (mesencephalon):}}\)
> roof/tectum: contains corpora quadrigemina
- superior colliculi: receive visual info from thalamus
- inferior colliculi: receive auditory info from medulla oblongata
> motor nuclei of reticular formation
- red: many blood vessels. proceses information form cerebellum/cerebrum, controls involuntary motor commands
- substantia nigra: controls motor output of basal nuclei
> cerebral peduncles: ascending, descending, transverse fibers, transmits info for motor commands from the cerebrum

Answer 4

Adapted from Human Anatomy, Martini, et. al. 9th edition