forebrain Flashcards
recall embryology
prosencephalon makes:
- telencephalon
- diencephalon
recall embryology
telencephalon and diencephalon makes:
telencephalon:
- cerebral hemispheres
- basal ganglia
diencephalon:
- thalamus
- hypothalamus
what is the thalamus and what does it do?
- egg-shaped structure
- relay center for motor and sensory information from body to brain
internal medullary lamina includes:
2 nuclei
- anterior nuclei
- medial dorsal nuclei
the anterior nuclei connect with:
the cingulate gyrus (above corpus callosum)
the medial dorsal nuclei connect with:
prefrontal cortex (frontal lobe)
- general patters of behavior
from the lateral view of the thalamus, what is now seen?
- the dorsal tier
- the ventral tier
*these divisions aren’t clear cut and need histological imaging
the ventral tier is made up of?
- ventral anterior nuclei
- ventral lateral nuclei
- ventral posterior lateral nuclei
the ventral anterior and ventral lateral nuclei:
- go to motor cortex
- involve the motor system
the ventral posterior lateral nuclei:
- receive info from medial lemniscus and spinothalamic tract
(somatosensory info) - sends information to post central gyrus cortex
the dorsal tier includes:
- lateral dorsal nuclei
- lateral posterior nuclei
- pulvinar nuclei
- medial geniculate
- lateral geniculate
the lateral dorsal nuclei and the lateral posterior nuclei:
- interconnect with the parietal lobe of the cortex
- deal with high functioning things
the pulvinar nuclei:
have indirect connectivity with the visual system and visual circuit
the medial geniculate:
is involved with auditory pathways
- go to the gyri of Heschl
the lateral geniculate:
is involved with the optic tract
- visual (occipital cortex)
the ventral posterior medial (VPM)
- deep inside the thalamus
- analogous to the VPL
- receives trigeminal pathways from the face
classifications of thalamic nuclei
- specific (relay) nuclei
- association nuclei
- non-specific nuclei
specific relay nuclei include:
- lateral geniculate
- medial geniculate
- ventral posterior lateral
- ventral posterior medial
- ventral anterior
- ventral lateral
- anterior
association nuclei include:
- medial dorsal
- lateral posterior
- lateral dorsal
- pulvinar
non-specific nuclei include:
- intralaminar nuclei
- reticular nucleus
lateral geniculate receives info from and sends info to:
from: the optic tract
to: the visual cortex (occipital)
the medial geniculate receives info from and sends info to:
from: auditory pathways
to: Heschl’s gyrus
the ventral posterior lateral (VPL) receives info from and sends info to:
from: medial lemniscus and spinothalamic
to: postcentral gyrus in parietal lobe
the ventral posterior medial (VPM) receives info from and sends info to:
from: medial lemniscus and spinothalamic and face
to: postcentral gyrus in parietal lobe
the ventral anterior and ventral lateral receive info from and send info to:
from: cerebellum and basal ganglia
to: motor cortex (precentral gyrus)
anterior nucleus receives info from and sends info to:
from: hippocampus
to: cingulate gyrus
what do specific (relay) nuclei do?
they receive info and relay the information to a specific area
what do association nuclei do?
they receive, process, and send information back to the same place in the cortex
the medial dorsal nuclei receives and sends info to:
the frontal and prefrontal cortex
the lateral dorsal and lateral posterior receives and sends info to:
the parietal lobe
the pulvinar nuclei receives and sends info to:
the occipital lobe
what do non-specific nuclei do?
they are involved in general behavior
the hypothalamus:
- is what?
- does what?
- composed of?
the part of the brain that produces hormones that control body temp, hunger, heart rate, mood
- is more reticular with a loose network
what is corpus striatum?
basal ganglia
major nuclei of basal ganglia?
- caudate
- putamen
- globus pallidus
where do the hippocampus and fornix form?
in telencephalon
where is the hippocampus located?
in the temporal lobe
what is the fornix?
the long c-shaped pathway of the hippocampus
- comes out of hippocampus and ends in mammillary bodies
what is the hippocampus?
- part of lymbic system
- structure that plays a role in memory and learning
what are the c-shaped structures?
- cortex
- lateral ventricle
- choroid plexus
- caudate nucleus
- fornix
what are the lateral ventricles?
structures that project into frontal, temporal, and occipital lobes and communicate with 3rd ventricle via the foramen of monroe
what is the choroid plexus?
a network of capillaries that produce CSF
what is the caudate nucleus?
a structure near the thalamus that travels inside the C-shaped ventricle
- movement, learning, memory, reward, motivation, emotion, and romantic interaction
what is the neocortex?
“the new cortex” that is part of the cerebral cortex where higher cognitive functioning is thought to originate from
what are the main cells of the neocortex?
the pyramidal cell
what are Brodmann’s areas?
- Brodmann = scientist who histological identified different areas of the brain
- the areas refer to the microscopic differences he notices
- up to 53 areas!!
areas we need to know: (numbers)
1
2
3
4
17
area 1, 2, and 3 refer to:
postcentral gyrus
area 4 refers to:
precentral gyrus
area 17 refers to:
visual cortex
what is a commissure?
something that connects one side of the brain to another
what is the corpus callosum?
- a large commissure that connects the left and right hemispheres of the brain
what are corticofugal fibers?
axons that come out of gyrus
classification of corticofugal fibers
- long projections fibers
- commissural fibers
- short association fibers
what are long projection fibers?
fibers (axons) that leave the cortex and brain
what are commissural fibers?
fibers (axons) that do not leave the brain
instead they got from one hemisphere to another (lots of them)
what are short association fibers?
fibers (axons) that travel from one gyrus to another
