Chapter 7 - Brain Stem and Cerebellum Flashcards
The three main external divisions of the brain stem
- medulla oblongata
- pons
- midbrain (mesencephalon)
- some include the cerebellum
The medulla and the pons are located _____ to the cerebellum
ventrally/anteriorly
The cerebellum is located _____ to the brainstem
dorsally/posteriorly
The cerebellum plays a major role in _______
motor coordination
The brain stem houses …
essential ascending and descending tracts and nuclei critical for the maintenance of life
The internal longitudinal divisions of the brain stem
- tectum
- tegmentum
- basis of pons
The tectum lies _____ to the midbrain and is separated by _____
- dorsal
- ventricular space filled with CSF
The tegmentum is the …
dorsal aspect of the brain stem itself
The basis of pons is the …
ventral bulge of the pons
The three cerebellar peduncles
- inferior
- middle
- superior
The cerebellar peduncles are …
- each peduncle is a stalk-like bundle of axons
- white matter pathways (tracts) connecting the brain stem and the cerebellum
- bilateral
The dorsal aspect of the midbrain has four hillocks (mounds) called the ____
quadrigeminal bodies
The quadrigeminal bodies are made up of ______ and _______
- two superior colliculi
- two inferior colliculi
The superior colliculi …
coordinate eye movements
The inferior colliculi …
deal with auditory reflex and bilateral sound localization (recognizing where a sound is coming from)
The internal structural components of the brain stem are …
- descending and ascending tracts
- cranial nerve nuclei
- reticular formation
- monoaminergic neuron pools (nuclei) and their output pathways
The descending and ascending tracts in the brain stem …
either terminate in or pass through the brain stem (relay station and/or conduit for pathways)
The cell bodies of most cranial nerves (cranial nerve nuclei) lie …
in the brain stem
The reticular formation is a ______. It is involved in …
- dense cluster of nuclei in the brain stem and tegmentum
- respiration, consciousness/unconsciousness, cardiovascular function/regulation, sleep, alertness (e.g. heartbeat, heart rate, blood pressure, etc.)
The monoaminergic neuron pools (nuclei) in the brain stem are …
- raphe nucleus
- locus ceruleus
- substantia nigra
The raphe nucleus is made up of _____ and is involved in _____. It projects to _____.
- serotonin neurons (indolamine neurons)
- wellness, sleep, appetite, pain control, etc.
- the cortex, hippocampus, basal ganglia, thalamus, cerebellum, spinal cord
The locus ceruleus is made up of _____ and is involved in _____.
- norepinephrine neurons (catecholamine neurons)
- fight or flight activation, alertness, etc.
The substantia nigra is made up of _____ and is involved in _____. The neurons project axons via the _____ to the _____. It plays a role (modulates) in _____ behavior.
- dopamine neurons (catecholamine neurons)
- modulating motor movement, motor tone, giving/reinforcing reward, etc.
- median forebrain bundle (MFB)
- striatum
- extrapyramidal motor
The motor tracts decussate in the _____, meaning that the left side of the brain controls the _____ side of the body, and vice versa.
- medulla
- right
The ascending tracts in the medulla
- fasciculus gracilus
- fasciculus cuneatus
- spinotectal
- spinocerebellar
- spinothalamic
The descending tracts in the medulla
- corticospinal
- rubrospinal
- olivospinal
- vestibulospinal
The internal structural components of the medulla are …
- descending and ascending tracts
- cranial nerve nuclei
- inferior cerebellar peduncle
The cranial nerve nuclei in the medulla
- hypoglossal (XII) nerve nucleus
- motor nucleus of the vagus (X) nerve
- 4 vestibular and 2 cochlear (VIII) nuclei