Brainstem Structures/Nuclei Flashcards
What is reticular formation?
Large network of multiple nuclei and ascending and descending neurons throughout the brainstem
What does the reticular formation do?
- Integrates sensory and cortical information
- Regulates motor activity and autonomic nervous system function
- Modulates pain
Location of reticular formation?
- Axons project all over the brain
- Origin of the reticulospinal tracts
- ARAS part of consciousness and sleep/wake systems
What does a large bilateral reticular formation lesion cause?
Coma
-Must have bilateral widespread injury of pons or midbrain
What is medulla - medullary rhythmicity center?
- Respiratory circuits controlling breathing
- Project to spinal cord C3-C5 and thoracic levels
- Spontaneously generate action potentials
- Allow you to breathe without constantly thinking about it
What is the medulla - olives?
-2 lumps posterolateral to medullary pyramids
What is the pons - Pontine nuclei?
Diffuse group of nuclei in basal pons
- Motor activity
- Receive input from all over the ipsilateral cerebral hemisphere (corticopontine neurons)
What it the pons - Pontine nuclei project to?
Contralateral cerebellar hemisphere (pontocerebellar fibers) via middle cerebellar peduncles
*Important for motor control
Location of cerebral peduncle?
Most ventral
-Contains: corticospinal, corticobrainstem and corticopontine tracts
What is the substantina Nigra?
Black substance
- Part produces dopamine
- Goes to parts of the brain for initiation and inhibition of movement as well as motivation and reward
Where is the substantia Nigra located?
Considered accessory to the basal nuclei in the cerebrum
-Most ventral structure in the tegmentum
Where is the red nucleus located?
Posteromedial to substantia nigra
Motor control in limbs
Origin of rubrospinal tract
Where is the inferior colliculus located?
Caudal to midbrain
Auditory rely
Relays auditory input to the superior colliculus and thalamus
Where is the superior colliculus located?
Rostral to midbrain tectum
Visual relay
Eye and head movements
Origin of tectospinal tracts
