Lecture 26: Mammalian Brain Anatomy Flashcards
what structures of the brain are derived within the telecenphalon
cerebral hemispheres and lateral ventricles
what structures of the brain are derived within the diencephalon
thalamus, hypothalamus, third ventricle
what structures of the brain are derived from the mesencephalon
cerebral peduncles and tectum, mesencephalic aqueduct
what structures are derived from the metencephalon
pons and cerebellum, fourth ventricle
what structures are derived from the myelencephalon
fourth ventricle
what is the order of anatomical brain divisions
telecephalon, diencephalon, mesencephalon, metencephalon, myelocephalon
the forebrain contains what structures
cerebral hemispheres, thalamus, hypothalamus
what functions does the forebrain perform
sensory processing, devision making, relay to/from body
what structures are contained within the brainstem
midbrain, pons, cerebellum, medulla
what functions does the brainstem perform
conduit of functions between spinal cord and forebrain, basic functions like breathing
what part of the brain contains the cranial nerve nuclei
brainstem
what region of the brain is the outer layer of the cerebrum that contains cell bodies of neurons
cortex or grey matter
what part of the brain receives visual information
occipital lobe
what part of the brain receives auditory information
temporal and parietal
what area of the brain is composed of myelinated axons
white matter
the ____ are the outer rings of cell bodies that communicate with other regions via large ____ which compose the white matter deep to the cortex
cerebral and cerebellar cortices, myelinated axons
what is the role of the granular layer in the organization of the white matter
local, synapses and information flow
RECEIVE INFORMATION
what is the role of pyramidal layers in the laminar organization of the grey matter
have long axons SEND INFORMATION to other areas
primary sensory cortical areas have a large ___ layer for receiving sensory input
4th layer
primary motor cortical areas have a large ____ layer for substantial output
5th layer
does grey or white matter lie deep to cerebral cortex
white matter
cell bodies are restricted to the ____region whereas axons____
cell bodies are restricted to the outermost region of the cortex in the grey matter region whereas axons travel to and form cortical regions
what are the 3 basic types of cortical connections formed by the white matter
association fibers, commissural fibers, projection fibers
what are association fibers
interconnection between white matter/axons from different areas of the cortex in THE SAME hemisphere
what are commissural fibers
interconnection between white matter/axons from corresponding structures BETWEEN hemispheres
what are projection fibers
corticoceptal- fibers entering the cortex
corticifugal- fibers exiting cortex
what is the corpus collosum
axonal tract that allows communication between lobes on right and left side
axons that communicate between the left and right side (corpus collosum) are called
commissural axons
what nuclei are responsible for relaying information to and from the cortex
thalamic nuclei
thalamic axons are example of what type of projection fibers
cortifugal- leaving cortex to brainstem or spinal cord
what region of the brain is responsible for regulating nervous and endocrine systems to maintain homeostasis
hypothalamus
what region of the brain releases hormones via hypophysis, regulates HR, BP, body temperature, water balance, appetite, circadian rhythms, emotion
hypothalamus
is hypothalamus mainly controlled by SNS or PNS
sympathetic
What serves as the conduit between brain and spinal cord, where motor and sensory tracts pass through
brainstem
what cranial nerves are located in the midbrain
CN III- oculomotor
CN IV- trochlear
what cranial nerves are located in the pons
CN V- trigeminal
CN VI- abducens
what cranial nerves are located in the medualla
CN VII–> CN XII
facial, vestibulocochlear, glosspharyngeal, vagus, accessory, hypoglossal
what is the order of meningeal layers most superficial to deep
dura mater, arachnoid space, pia mater
what is the subarchnoid space
deep to arachnoid mater and superficial to the pia, surrounds brain and spinal cord with CSF
flax cerebri
fold of dura between right and left hemispheres
tentorium cerebelli
fold of dura and bone between cerebrum and cerebellum
what is the function of the sinuses in the brain
receive venous drainage from the brain and orbit. this blood is then drained to vertebral and internal jugular vein
what is involved in the brains immune defense
T cells enter meninges through channels called sinuses, brain also contains microglia
what vessel primarily supplies blood to dura mater
middle meningeal artery (branch off maxillary artery) enters the cranial cavity via the oval foramen, largest blood vessel to dura and calavaria
where is CSF produced
ventricles- 2 lateral, third and fourth
what are choroid plexuses
vascular tufts into ventricles that release CSF an ultrafiltrate of blood plasma
what provides buoyancy, transports nutrients, flushes away waste products and serves as a medium for the diffusion of neuroendocrine and neurotransmitter substances
CSF
what is the pathway of CSF
choroid plexuses in ventricles–> subarchnoid space—> arachnoid granulations (back to venous system)
how does CSF get from third to fourth ventricle
cerebral aqueduct
what are subarchnoid cisterns
widest subarchnoid areas from which CSF can be extracted
how does CSF drain back into venous system
arachnoid granulations or villi
what two arteries supply the brain
internal carotid and vertebral arteries
what are the two branches off the internal carotid artery that supply the brain
rostral cerebral and middle cerebral
what are the four branches off the vertebral artery that supply the brain
basilar, rostral cerebellar, caudal cerebellar, and caudal cerebral
what arteries supply the cerebral hemispheres
rostral and middle cerebellar
what arteries supply the cerebral hemispheres and midbrain
caudal cerebral arteries
what arteries supply the midbrain, pons, rostral cerebellum
rostral cerebellar arteries
what arteries supply the caudal cerebellum
caudal cerebellar artery
what arteries supply the pons
basilar artery
