The flashcards below were created by user
on FreezingBlue Flashcards.
Describe the midbrain.
- Most complex and integrative portion of brain stem.
- Can direct complex motor patterns at subconscious level.
- Influences activity level of entire nervous system.
What are the components of the mid brain?
- Corpora quadrigemina
- Cerebral peduncles
- Red nucleus
- Reticular Formation & Reticular Activating System
What makes up the Corpora quadrigemina?
- Superior colliculus
- Inferior colliculus
What is the function of the superior colliculus?
- Receives visual inputs from thalamus.
- Controls reflex movements of eyes, head, and neck in response to visual inputs.
What is the function of the inferior colliculus?
- Receives auditory data from nuclei in medulla oblongata and pons.
- Controls reflex movements of head, neck, and trunk in response to auditory inputs.
What is the function of the cerebral peduncles
Main motor pathway between cerebrum and lower parts of the nervous syste.
What is the red nucleus and what is its function?
- Receives information from cerebrum and cerebellum.
- Issues commands that affect upper limb position and background muscle tone.
What are Substantia nigra?
They are dark cells that adjust basal nuclei activity in cerebrum, found in the red nucleus.
What is the Reticular Formation & Reticular Activating System (RAS)?
- Consists of nuclei of gray matter found in the brain stem (medulla, pons, midbrain).
- Radiating axon fibers extend from the reticular formation to neurons in the diencephalon (thalamus & hypothalamus), basal nuclei of cerebrum, cerebellum, cerebral cortex
Describe the relationship of the RAS and the cerebral cortex.
- when sensory impulses reach the reticular formation axons, RAS stimulates the cerebral cortex into a state of consciousness and wakefulness.
- inhibition of RAS causes sleep
- if RAS or connections to it are damaged, or the cerebral cortex is damaged, the cortex cannot be aroused to a conscious state = coma