medulla oblongata Flashcards
What does the medulla oblongata connect superiorly and inferiorly?
The medulla oblongata connects the pons superiorly with the spinal cord inferiorly.
At what level does the medulla transition into the spinal cord?
The medulla transitions into the spinal cord at the level of the foramen magnum.
Which spinal nerve originates at the medulla-spinal cord junction?
The first cervical spinal nerve originates at the medulla-spinal cord junction.
What is the anterior median fissure of the medulla oblongata continuous with?
The anterior median fissure of the medulla oblongata is continuous with the spinal cord’s fissure.
What structures contain corticospinal fibers in the medulla?
The pyramids contain corticospinal fibers in the medulla.
What is the function of the corticospinal fibers?
The corticospinal fibers are responsible for voluntary motor control.
Where do most corticospinal fibers cross to the opposite side?
Most corticospinal fibers cross at the decussation of pyramids.
What structures are located lateral to the pyramids?
The olives are located lateral to the pyramids.
What do the olives contain?
The olives contain the inferior olivary nuclei.
Where does the hypoglossal nerve (CN XII) exit the medulla?
The hypoglossal nerve (CN XII) exits between the pyramid and the olive.
Which cranial nerves exit between the olive and the inferior cerebellar peduncle?
The glossopharyngeal (IX), vagus (X), and accessory (XI) nerves exit between the olive and the inferior cerebellar peduncle.
What part of the fourth ventricle does the posterior surface of the medulla form?
The posterior surface of the medulla forms the lower part of the fourth ventricle.
What are the gracile and cuneate tubercles?
The gracile and cuneate tubercles are swellings due to underlying gracile and cuneate nuclei.
What happens at the level of the decussation of pyramids?
At this level, motor decussation occurs as corticospinal fibers cross to form the lateral corticospinal tract.
Which nuclei process sensory information at the level of the decussation of pyramids?
The nucleus gracilis and nucleus cuneatus process sensory information.
What does the substantia gelatinosa continue as in the medulla?
The substantia gelatinosa continues as the nucleus of the spinal tract of the trigeminal nerve.
What happens at the level of the decussation of lemnisci?
Sensory decussation occurs as internal arcuate fibers from nucleus gracilis and nucleus cuneatus cross to form the medial lemniscus.
What information does the spinal lemniscus carry?
The spinal lemniscus carries pain, temperature, and touch information via the spinothalamic and spinotectal tracts.
Which nucleus at the level of the olives coordinates motor functions with the cerebellum?
The inferior olivary nucleus coordinates motor functions with the cerebellum.
Which vestibular nuclei are visible at the level of the olives?
The medial and inferior vestibular nuclei are visible at the level of the olives.
Where are the cochlear nuclei located in the medulla?
The cochlear nuclei are located on the inferior cerebellar peduncle.
Which nucleus contains motor neurons for CN IX, X, and XI?
The nucleus ambiguus contains motor neurons for the glossopharyngeal, vagus, and accessory nerves.
What is the function of the medial lemniscus in the medulla?
The medial lemniscus carries sensory information to the thalamus.
Which structure connects the medulla to the cerebellum?
The inferior cerebellar peduncle connects the medulla to the cerebellum.
What structure in the medulla coordinates eye movements?
The medial longitudinal fasciculus (MLF) coordinates eye movements.
What is the function of the reticular formation in the medulla?
The reticular formation is involved in autonomic functions and consciousness.
Where do cranial nerve fibers emerge in the medulla?
Cranial nerve fibers emerge from the reticular formation to their respective exit points.
How does white and gray matter arrangement change just inferior to the pons?
There is little change in white and gray matter arrangement compared to the previous level.
What vital functions does the medulla control?
The medulla controls cardiac, respiratory, vasomotor, and reflex functions.
What role does the medulla play in sensory and motor pathways?
The medulla serves as a relay center for sensory and motor pathways.
Which cranial nerve nuclei in the medulla coordinate swallowing, speech, and balance?
The cranial nerve nuclei in the medulla that coordinate these functions are those of the glossopharyngeal, vagus, accessory, and vestibulocochlear nerves.
Why is the medulla essential for survival?
The medulla is essential for life-sustaining functions and acts as a crucial communication hub between the brain and spinal cord.
