lecture 22: subcortical fibers Flashcards
what are the 3 general categories of the white matter pathways of the brain
commissural fibers
association fibers
projection fibers
connect cortical areas of the left and right hemispheres (across the midline)
what type of fibers
comissural
what do commisurral fibers connect
connect cortical areas of the left and right hemispheres (across the midline)
give an example of a commissural fibers
corpus calosum
connect cortical areas within the same cerebral hemisphere (one side of the brain)
what type of white matter fibers
association fibers
what do assication fibers connect
connect cortical areas within the same cerebral hemisphere (one side of the brain)
give an example of an association finer
fibers connecting occipital lobe to temporal
connect the cerebral cortex and subcortical structures of the CNS
what white matter fibres
projection fibres
What do projection fibers connect
connect the cerebral cortex and subcortical structures of the CNS
give an example pr projection fibers
corona radiate
internal capsule
true or false: the internal capsule white matter is considered association fibers and explain
false, they are projection fibers since they are connectio=ng the cerebral cortex to subcortical structures (thalamus)
what white matter fiber category does corpus callosum belong to (C, A, P?)
commissural
what is the largest commissural tract in the brain
corpus callosum
true or false: the corpus callosum is the the largest commissural tract in the brain
true
what are the 4 divisions of the corpus callosum
rostrum
splenium
body
genu
is rostrum of corpus callosum near pineal gland or pituirary gland
pituitary gland
is splenum of corpus callosum near pineal gland or pituirary gland
pineal gland
what connects the frontal lobes in the corpus callosum
forceps minor (ant forceps)
what connects the occipital lobes in the corpus callosum
forceps major
true or false: the forceps minor connects occipital lobe
false, connects the frontal lobes
what part of the corpus callosum makes up the forceps minor
genu
what part of the corpus callosum makes up the forceps major
splenium
splenium of the CC makes the forceps major or forceps minor
major
genu of the CC makes the forceps major or forceps minor
forceps minor
what are the u shaped fibers in the corpus callosum connecting lobes
forceps minor and major
in the forceps minor more anterior or posterior
anterior
in the forceps major more anterior or posterior
posterior
what are the 4 examples of commissural fibers
corpus callus (forceps major and minor)
anterior comissure
posterior commissure
hippocampal commisuri
which commisural finer connects the left and right temporal lobe
anterior commisirea
anterior or posterior commisural finer connects the left and right temporal lobe
anterior commissure
is the anterior commissure located near rostrum or selenium of CC
rostrum
explain how the anterior commissure contains olfactory fibers
medial olfactory stria decussates via anterior commissure to go to contralateral olfactory bulb (for localization of smells)
what is another name for the posterior commissure and why
epithalamic commisure
the psoturerior commissure is part of what structures
epithalamus
and component of the inferior lamina of the pineal gland
olfactory fibers are involved in the anterior or posterior commissure
anterior
pupillary light reflex is involved with the anterior or posterior commissure
posterior (pretectal cross over in the posterior commissure)
explain how the posterior commissure is involved i the pupillary light reflex
the pretectal nuclei project to the bilateral accessory oculomotor nucleus and decussate via the posterior commissaire
what white matter fibre connects the two hippocampi
hippocampal commissure
ADD SLIDES ABOUT THE SPLIT BRAIN SYNDROME
WHAT Do short association fibers connecti
adjacent gyri
what are the white matter fibers that connect adjacent gyri caleld
short association fibers
what are 5 examples of long association fibers
cingulum
superior longitudinal fasicualtus
inferior longitudinal fascicles
occipitofrontal fascicle
uncinate fasciculi
cingulum
superior longitudinal fasicualtus
inferior longitudinal fascicles
occipitofrontal fascicle
uncinate fasciculi
are short or long association fibers
long
true or false: long association fibers connect 1 lobe to another within the same hemisphere
true
which association fiber connects different regions of the limbic cortex
cingulum
what does the cingulum connect
connects different regions of the limbic cortex
where is the cingulum located
wraps around corpus calosum, into temporal lobe
(tracts from the cingulum are within subcollasal, ci=ngulate and parrahippo)
wraps around corpus calosum, into temporal lobe
what white matter long association fiber>
cingulum
tracts from the cingulum are within which gyri
subcollsoal
cingulate
parahippocampal
what is the function of the cingulum
attention, memory, emotion, homeostasis
attention, memory, emotion, homeostasis is assocaited with what association fiber
cingulum
what does the superior longitudinal fasciculus connect
connects frontal, parietal, occipital and temporal lobes
where is the location of the superior long fasciculus
above the insula
which association fiber is located above the insula
superior longitudinal
what is considered a subset of the superior longitdinal fascicles that is important for language
arcuate fasciuculus
true or false, the arcuate fascicles is a subset of the inferior longitudinal fasculus
false, of the superior
what is the roles of the superior longitudinal fascicles
roles in language, controlling speech, coordination of eye movements to track visual stimuli (frontal eye fields and PTO)
roles in language, controlling speech, coordination of eye movements to track visual stimuli (frontal eye fields and PTO)
which association fiber
superior longitudinal fasciulus
explain how the superior longitudinal fascicles is involved in coordination of eye movements to track visual stimuli
connections from frontal eye fields and PTO to PPRF
what does the inferior longitudinal fasciculus connect
connects occipital and temporal lobes (ventral stream of visual processing)
where is the location of the inferior long fasciculus
below the insula
which association fiber is located below the insula
inferior longitudinal fasciulus
facilitates rapid transfer of visual info to limbic structures for visual memory, perception and facial recognition
which association fiber
inferior longitudinal fasculusw
what is the function of the inferior longitudinal fasciculus
facilitates rapid transfer of visual info to limbic structures for visual memory, perception and facial recognition
is the occipitofrontal fasciculi in a caudal-rostral orientation
or ventral dorsal
caudal rostral
where do the occipitofrontal fascicle carry information
from the caudal aspect of the brain (esp occipital lobe) to the prefrontal cortex
occipitofrontal fascicoli carry info rom the caudal aspect of the brain (esp occipital lobe) to the BLANK
prefrontal cortex
what is the function of the occipitofrontal fascicle
carry sensory info to the prefrontal cortex for attention, decision making and language functions
true or falseL the occipital frontal fascicle is decision making based on visual info
true
what does the uncinate fascicles connect
connects limbic structures in the temporal lobe and prefrontal cortex
connects limbic structures in the temporal lobe and prefrontal cortex
is assocaited with what association fibers
uncinate
the rostral fibers of the uncinate fascicles mix with what other structure
the occipitofrontal fascicles
function of the uncinate fascicles
theories include episodic memory, language, and social emotional processing
theories include episodic memory, language, and social emotional processing
function of what association fiber
uncinate
what is episodic memory
memory information about the time and place of an event, as well as detailed information about the event itself.
collection of efferent and afferent pathways connection cortical and subcortical structures is what type of white matter fibers
projection fibers
what are 4 examples of the projection fibers
corona radiate
internal capsule
external capsula
extreme capsule
what is the corona radiate
fan-shaped white matter sheet
connects cortex and basal ganglia is what white matter projection fiber
external capsule
what does external capsule connect
connects cortex and basal ganglia
what does the extreme capsule connect
connects claustrum and insula
connects claustrum and insula is what white matter projection fiber
extreme capsule
what are the caudal most projections of the corona radiate
optic radiations
what is the primary function of the optic radiations
to carry visual info from the thalamus to the visual cortex
what forms the walls of the lateral ventricles
caudate
what forms the lateral walls of the 3rd ventricle
thalamus
true or false, the internal capsule is an association fiber
false, it is a projection fiber
where is the posterior limb of IC located
between thalamus and LF
what supplies the posterior limb
anterior choroidal
what are the fibers of the posterior limb
corticospinal
corticopontine (cerebrocerebellar pathway)
corticofugal (central central of extrapyramidal)
3rd order sensory fibers (thalamocortical)
what are the primary fibers of the genu of the IC
primarily corticonuclear fibers (and sensory info from the face)
where is the anterior limb located
between head of caudate and lentiform nucleus
what fibers are located in the anterior limb
corticopontine
corticofugak
other thalamocortical fibers
=no voluntary of concious pathways that pass here
auditory and optic radiations radiate from where to where
radiate from medial and lateral geniculate nuclei to cortex
what radiates from medial and lateral geniculate nuclei
auditory (medial)
optic (lateral)
