Brainstem, cranial nerves, anatomy of cerebellum/diencephalon/telencephalon Flashcards
medulla pyramids are located
in between VMF and VLS (ventromedial fissure and sulcus)
every motor fiber crosses here at the spinomedullary junction
decussation of pyramids
bundles of nerve fibers that originate in the motor cortex, descend to innervate neurons in brainstem and spinal cord
corticospinal/corticobulbar tract
basilar artery sits here
basilar groove (in pons)
3 things in ventral midbrain
interpeduncular fossa, crus cerebri/cerebral peduncles, optic tract/chiasm
3 things in dorsal medulla
dorsal median/lateral/intermediate sulci, cunate and gracile tubercle, cunate and gracile nuclei
dorsal pons
floor of 4th ventricle
dorsal midbrain has
superior and inferior colliculi
superior colliculi
relay stations for visual systems
inferior colliculi
relay stations for auditory systems
internal features of medulla
non-cranial nerve nuclei, cranial nerve nuclei, white matter tracts (corticospinal-corticobulbar tact)
internal features of pons
non-cranial nerve nuclei, cranial nerve nuclei, longitudinal fibers, transverse fibers (pontocerebellar fibers)
internal features of midbrain
tectum, tegmentum, cerebral peduncles, substantia nigra
lies dorsal to cerebral aqueduct and consists mainly of paired colliculi; roof
tectum
ventral to aqueduct and contains ascending and descending tracts, nuclei of cranial nerves
tegmentum
corticospinal/cortiobulbar motor fibers =
basis penduculi (cerebral peduncles)
large motor nucleus between tegmentum and BP; affected in people with parkisons
substantia nigra
functional significance of medulla
cardiovascular regulation, motor speech, balance and coordination
syndromes of medulla
arnold chiari malformation and lateral medullary syndrome
arnold chiari malformation
herniation of cerebellum and medulla through foramen magnum
lateral medullary syndrome
damage of lateral medulla due to disruption of its blood supply (vagus n)
functional significance of the pons
respiration and consciousness through reticular activating formation (damage may affect sensation and movement in face)
syndrome of pons
locked in syndrome - significant damage to ventral pons and basilar artery - eyes track/express emotions but cannot speak/move
functional significance of midbrain
visual/auditory/motor systems, pain modulation
areas of the midbrain are frequently damages in pathology that involves
raised intra-cranial pressure
cerebellum connected to dorsal brainstem by 3 pairs of large white matter fiber pathways called
cerebellar peduncles
cerebellar peduncles form the
lateral walls of the fourth ventricle
contain efferent fibers from cerebellum and attach to midbrain just inferior to inferior colliculi
superior cerebellar peduncle
contain afferent fibers destined for cerebellum, attached to lateral border of pons
middle cerebellar peduncle
contain both afferent/efferent from cerebellum, attached to dorsolateral medulla
inferior cerebellar peduncle
location of thalamus
below lateral ventricles
location of hypothalamus
below, in front of thalamus
location of third ventricle
center or brain; below corpus callous and body of lateral ventricles, between 2 thalami
location of pineal gland
between superior colliculi of midbrain
location of maxillary bodies
protrude from ventral hypothalamus
location of pituitary gland
protrude from ventral hypothalamus
4 major areas of diencephalon
thalamus, epithalamus, hypothalamus, subthalamus
function of thalamus
integrate and relay sensory info
function of epithalamus
processes olfactory, limbic, and autonomic (emotions and memories)
pineal gland delays
onset of puberty
hypothalamus function
homeostasis and physiological function (eating, temp, hormones, sleep, etc)
sub thalamus function
part of basal ganglia, regulate movement
clinical problems associated with thalamic dysfunction
lesions - loss or distortion of specific sensations
clinical problems associated with sub thalamic dysfunction
hemiballismus - ballistic movement on one side of the body (opposite side of lesion is affected)
location of primary motor area
frontal lobe, precentral gyrus, medial and lateral surface
major role of primary motor area
voluntary execution of skilled movement, controls opposite side of the body
lesions of primary motor area
weakness and other motor symptoms on contralateral side of body
location of premotor area
frontal lobe, rostral to precentral gyrus, lateral only
major role of premotor area
motor planning for externally guided movement
lesions in premotor area
apraxia or motor planning disorder
location of supplementary motor cortex
frontal lobe, rostral to precentral gyrus, medial only
major role of supplementary motor cortex
motor planning for internally guided movement
lesions in supplementary motor cortex
apraxia or motor planning disorder
location of frontal eye field
frontal lobe, lateral only
major role of frontal eye fields
voluntary eye movements for intentional exploration of environment
major role of prefrontal area
affective behaviors, judgment, problem solving, social appropriateness
lesions in prefrontal area
apathy, poor motivation, flat affect, socially inappropriate, poor judgement
major role of broca’s area
expressive language
primary sensory area location
parietal lobe, posterior to central gyrus
major role of primary sensory area
detection and localization of sensation from opposite side of body
lesions to primary sensory area
sensory deficits on contralateral side of body
major role of sensory association area
sensory processing and perception
lesions to sensory association area
stereognosis
major role of wernicke’s area and lesion
language comprehension (receptive language); lesion is receptive aphasia
lesion in primary visual cortex
hemianopsia (loss of vision in half of visual field)
which telencephalon structures are part of the basal ganglia
putamen, caudate, globus pallidus, substantia nigra
function of basal ganglia
influences motor control
function of corpus callosum
commissural pathway that crosses midline; connects sides of CNS