1: Anatomy - CNS Overview Flashcards
What are the two main divisions of the nervous system?
Central nervous system (CNS)
Peripheral nervous system (PNS)
Remember there’s the Enteric nervous system as well
Which organs make up the CNS?
Brain
Spinal cord
Which nerves make up the PNS?
Cranial nerves
Spinal nerves and all their branches
What is the embryological origin of the brain?
Neural tube
Imagine you’re looking at the inferior surface of the brain. What are the three embryological vesicles it originates from, anterior to posterior?
Prosencephalon (most anterior)
Mesencephalon
Rhombencephalon (most inferior)
What three structures, from superior to inferior, make up the brainstem?
Midbrain
Pons
Medulla oblongata
think MPM (and midbrain must be at the top)
Which CNS cells receive, process and send information?
Neurons
What are the
a) projections
b) bodies
of neurons called?
a) Dendrites and axons
b) Soma
What is the difference between a dendrite and an axon?
Dendrites receive impulses
Axons send impulses
Neurons usually have many dendrites but only one axon
What word is used to describe a neuron with many dendrites?
Multipolar
What are glial cells?
Support cells
Which type of glial cell supports other brain cells and maintains homeostasis?
What important structure do they maintain?
Astrocytes
Blood-brain barrier
Astrocytes support the endothelium of brain capillaries to maintain which structure?
Blood brain barrier
Which substance insulates axons to increase conduction velocity?
Myelin
Which glial cells produce myelin?
Oligodendrocytes
Which glial cells are part of the immune system?
Microglia
Which immune cells do microglia closely resemble?
Macrophages
Which glial cells line the ventricles of the brain and closely resemble epithelial cells?
Ependymal cells
What is the function of
a) oligodendrocytes
b) astrocytes
c) ependymal cells
d) microglia?
a) Lay down myelin sheathes
b) Homeostasis, blood brain barrier
c) Line CSF-filled ventricles
d) Immune surveillance
What are the two types of matter found in the brain?
Grey matter
White matter
What are the names are given to the
a) bumps
b) grooves
c) really deep grooves
of the brain?
a) Gyrus (gyri)
b) Sulcus (sulci)
c) Fissure
In which matter are
a) the bodies of neurons and glial cells
b) axons
found?
a) Grey matter
b) White matter
Grey and white matter is also found in the spinal cord.
What shapes is white matter arranged into?
Anterior, posterior and lateral columns
Grey matter is generally found on the ___ of the brain and the ___ of the spinal cord.
outside of the brain
inside of the spinal cord
Is white matter found on the inside or the outside of the brain?
Inside
imagine the projections running from the inner brain to the spinal cord; remember the internal capsule (a central structure) is where white matter travels
In the spinal cord, what is grey matter arranged into?
Anterior and posterior horns
Where in the spinal cord is grey matter found?
Inside
In an H shape
Which neurons are found in the anterior horn of the spinal cord?
Motor neurons
Autonomic neurons
Which neurons are found in the posterior horn of the spinal cord?
Sensory neuron
The central sulcus runs along the middle of the brain on the coronal plane.
Which two areas are found anterior and posterior to this sulcus?
What are their other names?
Pre-central gyrus OR Motor strip OR Primary somatomotor area
Post-central gyrus OR Sensory strip OR Primary somatosensory area
Which fissure divides the frontal and parietal lobes from the temporal lobe below?
Lateral fissure / Sylvian fissure
If you were to take a coronal view of the brain and draw a line down the midline, which fissure would the line run through?
Longitudinal fissure / Interhemispheric fissure
What is the bridge of white matter which crosses the midline of the brain on an axial plane?
Corpus callosum
Superior to the lateral ventricles
Which tract of white matter connects the brainstem and spinal cord to the cerebral cortex?
Internal capsule
Which fissures / sulci are found
a) along the midline, on the sagittal plane
b) along the midline, on the coronal plane
c) above the corpus callosum, seen only from a sagittal view
d) in the occipital lobe, seen only from a sagittal view
e) separating the parietal and occipital lobes?
a) Longitudinal fissure
b) Central sulcus
c) Cingulate sulcus
d) Calcarine sulcus
e) Parieto-occipital sulcus
What is the name given to a space within the brain which contains CSF?
Ventricle
How many lobes does each brain hemisphere have?
5
4 named for the bones and the insular lobe (found deep to other lobes)
What are the three layers of the meninges (from superficial to deep)?
Dura mater
Arachnoid mater
Pia mater
What is found deep to the arachnoid mater, before the pia mater?
Subarachnoid space
What is found in the subarachnoid space?
CSF
What feature of the arachnoid mater allows CSF to drain to the dural sinuses?
Arachnoid granulations
How thick is the pia mater?
Very very thin
What holes connect the
a) subarachnoid space and lateral ventricles
b) lateral and 3rd ventricles
c) 3rd and 4th ventricles?
a) Subarachnoid granulations
b) Interventricular foramen (of Monro)
c) Cerebral aqueduct
Which space allows CSF to enter the brainstem and spinal cord?
Central canal
Which arteries give off
a) the anterior and middle cerebral arteries
b) the posterior cerebral and basilar arteries?
a) Internal carotid arteries
b) Vertebral arteries
Which anastomosis of arteries supplies much of the brain?
Circle of Willis
Which hole in the base of the skull drains blood into the internal jugular vein?
Jugular foramen
List from anterior to posterior the following vesicles of the early brain:
mesencephalon, prosencephalon, rhombencephalon
Prosencephalon
Mesencephalon
Rhombencephalon
Later in development, there are five vesicles forming the brain instead of three.
What are they called, from anterior to posterior?
Prosencephalon splits into TELENCEPHALON and DIENCEPHALON
Mesencephalon remains
Rhombencephalon splits into METENCEPHALON and MYELENCEPHALON
List, from anterior to posterior, the five vesicles of the early brain.
Telencephalon
Diencephalon
Mesencephalon
Metencephalon
Myelencephalon
What does the telencephalon (most anterior brain vesicle) develop into?
Right and left cerebral hemispheres
i.e the big bulky masses of the brain
What does the diencephalon develop into?
Thalamus and Hypothalamus
di - so it develops into two things
What does the mesencephalon develop into?
Midbrain
mes - think middle
What does the metencephalon develop into?
Pons
Cerebellum
What does the myelencephalon (most posterior vesicle) develop into?
Medulla oblongata
Name the vesicles which give rise to the
a) cerebral hemispheres
b) thalamus and hypothalamus
c) midbrain
d) pons and cerebellum
e) medulla oblongata
a) Telencephalon
b) Diencephalon
c) Mesencephalon
d) Metencephalon
e) Myelencephalon
Which brain structure is found within the third ventricle of the brain is described as “two potatoes touching one another”?
Thalamus
Which hole connects the lateral ventricles and the third ventricle?
Interventricular foramen
Which bit of tissue connects the two halves of the thalamus within the third ventricle?
Interthalamic adhesion
Which gland is connected to the posterior part of the third ventricle and produces melatonin?
Pineal gland
What are the five lobes of the brain?
On each side:
frontal lobe
parietal lobe
temporal lobe
occipital lobe
insular lobe
separated by the longitudinal fissure
Which sulci separate the
a) frontal lobe and parietal lobe
b) parietal lobe and temporal lobe
c) parietal lobe and occipital lobe?
a) Central sulcus
b) Lateral fissue
c) Parieto-occipital sulcus
Which landmark separates the occipital lobe from the cerebellum?
Preoccipital notch
Where is the insular lobe found?
Deep to the temporal lobe
You can’t usually see it
Where is CSF produced?
Choroid plexuses in the ventricles
From which structures does blood from the brain drain into the internal jugular vein?
Dural venous sinuses
so the cavernous sinuses and intercavernous sinuses
