Brainstem Flashcards
Midbrain (mesencephalon) anatomy
- tectum
- tegmentum
- cerebral peduncles
- cerebral aqueduct
- basilar artery
- trochlear nuclei (CN IV)
Tectum structures
Superior and inferior colliculus
Tegmentum structures
- reticular formation
- periacqueductal gray
- substantia nigra
- red nucleus
- cerebellar peduncles
Superior colliculus function
Integrates visual, auditory and somatosensory spatial info to initiate orienting movements of the eyes and head toward salient objects in space
Superficial layers of superior colliculus functions
Receives visual info from the retina and the visual cortex
Deep layers of superior colliculus functions
Receives info from the auditory, visual, and somatosensory system
Inferior colliculus function
Largest nucleus of the auditory system in humans and the point in the brainstem where all auditory pathways traveling through the brainstem converge; also the point from which auditory pathways branch out to carry auditory info on to other areas of the brain like the SC
Inferior colliculus neurons
Specialized to respond to cues that allow for localization of sound or the determination of where in space sound is coming from
Cerebral peduncles
Two stalks that attach the cerebrum to the brain; arise from ventral pons and contain large ascending (sensory) and descending (motor) nerve tracts that run to and from the cerebrum from the pons
Important fiber tracts that run through cerebral peduncles
- corticospinal
- corticopontine
- corticobulbar
Cerebellar peduncles
- A paired structure of white matter that connects the cerebellum to the midbrain
- consists of mainly efferent fiber
- connects cerebellum to midbrain
Efferent fiber in cerebellar peduncles
Cerebellothalamic tract that runs from a cerebellar hemisphere to the contralateral thalamus and the cerebellorubral tract that runs from a cerebellar hemisphere to the red nucleus
Pons (metencephalon) anatomy
- basilar pons (ventral)
- middle cerebellar peduncle
- basilar artery
- 4th ventricle
- trigeminal (V), abducens (VI), facial ((VII), vestibulocochlear nuclei (VIII)
Pons function
Pons works with the medulla oblongata to generate the respiratory rhythm of breathing
Medulla oblongata (myelencephalon) anatomy
- nucleus cuneatus
- nucleus gracilis
- internal arcuate fibers
- pyramids
- inferior cerebellar peduncle
- basilar artery
- glossopharyngeal (IX)
- vagus (X)
- accessory (XI)
- hypoglossal nuclei (XII)
