Central Nervous System (CNS) - CORRECT ANSWERS-Consists of the brainstem, the
cerebellum, the diencephalon, and the cerebrum
brainstem - CORRECT ANSWERS-consists of 3 parts: the medulla oblongata, pons, and
midbrain, plus the reticular formation
medulla oblongata - CORRECT ANSWERS-often called the medulla (3 cm long); most inferior
port of the brainstem; contains sensory and motor tracts, cranial nerve nuclei, and related
nuclei. Involved with regulating heart rate, blood vessel diameter, respiration, swallowing,
vomiting, hiccuping, coughing and sneezing.
medulla decussation - CORRECT ANSWERS-On the inferior ends of the pyramids, most of the
fibers of the descending tracts cross to the opposite side (or decussate). This accounts in part
for the fact that each half of the brain controls the opposite half of the body.
pons - CORRECT ANSWERS-the part of the brainstem just superior to the medulla oblongata;
contains ascending and descending tracts and several nuclei; relays information between
cerebrum and cerebellum; site of reflex centers; sleep and respiratory center
midbrain - CORRECT ANSWERS-smallest region of the brainstem, located just superior to the
pons; contains ascending and descending nerve tracts; serves as visual reflex center; part of
auditory pathway
reticular formation - CORRECT ANSWERS-scattered throughout brainstem; controls many
brainstem activities, including motor control, pain perception, rhythmic contractions, and the
sleep-wake cycle.
cerebellum - CORRECT ANSWERS-attached to the brainstem posterior to the pons; it
communicates with other regions of the CNS; involved in control of balance, posture,
locomotion, and fine motor coordination producing smooth flowing movements.
diencephalon - CORRECT ANSWERS-part of the brain between the brainstem and cerebrum;
main components are the thalamus, sub thalamus, epithalamus, and hypothalamus.
thalamus - CORRECT ANSWERS-the largest part of the dienchephalon; all sensory neurons
that project to the cerebrum first synapse here except for the olfactory neurons (considered the
sensory relay center of the brain); influences mood and actions such as fear or rage.
subthalamus - CORRECT ANSWERS-small area immediately inferior to the thalamus; is
involved in controlling motor functions