CNS Flashcards
What is the CNS protected by
Bones, cerebrospinal fluid, and meninges
What is Cerebrospinal fluid
Composed of water, protein, glucose and electrolytes
Where is CSF located
Circulate in subarachnoid spec and ventricles and central canal in spinal cord
Choroid plexus
Cluster of blood vessels and ventricles
ependymal cells that produce CSF
What are the functions of CSF
Cushion and protect CNS
Transport nutrients and waste products
Meninges
Connective tissue surrounding CNS
Dura mater
Tough fibers putter most layer
Helps to partition and hold the brain in place inside that skull
In dura mater there is the flax cerebri that is
Large, sickle-Shaped Vertical sheets that lies within the longitude fissure between the two hemisphere
Attaches anteriorly to the crista galli of the ethmoid
Dura mater
Falx cerebelli
Vertical partition that runs along the vermis of cerebellum
Dura mater
Tentorium
Horizontal sheet that lies transverse fissure between the cerebrum and cerebellum
Arachnoid Mater
Fibrous middle layer
Arachnoid Mater
Subdural space
Potential space between the Dura and arachnoid Mater
Potential space
Normally empty but can’t fill with fluid or blood due to disease or trauma
Arachnoid Mater
Subarachnoid space
Cavity directly underneath arachnoid mater
Between the arachnoid and pia mater
Contains CSF
Pia matter
Thin vascular inner most layer
Found directly adhered to surface of brain and spinal cord
Ventricles
Net worth of cavities and canals in CNS
help circulate CSF
Lateral ventricles
Two cavities in each Cerebral hemisphere
Third ventricle
Unpaired cavity in diencephalon 
Cerebral aqueduct
Connects third and fourth ventricle
Fourth ventricles
Unpaired cavity located in brainstem
Communicates with the central canal of the spinal cord in the subarachnoid space
What neuroglia makes CSF
Ependymal cells
What is the network of blood vessels found in the ventricles that contain the neuroglia that makes CSF
choroid plexus
Cerebrum
Largest part of brain accounts for 80% of total brain mass
divided into two left and right hemispheres which are made of gray and white matter
Gray matter
Masses of neural soma located in the cerebral cortex and in deeper clusters called brain nuclei
cerebral Cortex
Outer superficial layer of gray matter arrange in gyri and sulci
Gyri
Raised ridges
Sulci
Grooves
Fissure
Especially deep sulcus
Longitudinal fissure
Separates right and left hemisphere
Transverse cerebral Fissure
Separate Cerebrum from cerebellum
White matter
Bundles of axons and neuroglia
Located in deeper part of cerebrum
Corpus callosum
Large central track of white matter
deep to longitudinal tissue
connects right and left hemisphere
Tracts
Bundles of white matter who’s axons travel together
Nuclei
Cluster of gray matter within white matter
 Cerebral lobes
One way to organize the cerebral hemisphere is dividing into lobes
which are paired
Frontal lobe
Anterior lobe deep to frontal bone
Central sulcus
Separate frontal and parietal lobes
Precentral gyrus
Area of frontal lobe anterior to central sulcus
parietal lobe
Superolateral lobe deep to parietal bone
Temporal lobe
Inferolateral Load deep to temporal bone
Lateral fissure
Separate temporal lobe from frontal and parietal lobe
Cerebral cortices
Rind or outer layer
Primary somatosensory cortex
Postcentral gyrus of parietal lobe
Receives input from general somatic senses ( touch, pressure, vibration)
Priprioception
Sense of limb or joint position
Contra lateral projection
Each cerebral hemisphere receives sensory input from opposite side of the body
Primary auditory cortex
Superior Edge of temporal lobe
receive sound input
Primary visual cortex
Occipital lobe
receive visual input
Gustatory cortex
Interior limbic lobe
Receive taste input
Olfactory cortex
Medial aspect of temporal lobe
receives smell input
Primary motor cortex
Precentral gyrus a frontal lobe controls voluntary movement by synapsing to Somaticmotor neuron
Broca’s area
Frontal lobe of left hemisphere
control motor movement for speech
Association areas
Asked to integrate multiple sensory input with memories of past experience
Anterior Association area
Prefrontal cortex
most anterior part of frontal lobe thought and personality
Higher level thinking and predicting consequences of actions
Left cerebral hemisphere is responsible for
Language processing and analytical Task like math and logic
Detail oriented
Wernicke‘s area 
Responsible for language comprehension
on the left hemisphere
Right cerebral hemisphere is responsible for
 analyzing and interpreting visual auditory information
Recognizing faces creating and appreciating music
Big picture hemisphere
Diencephalon
Enclosed by cerebrum links cerebrum to brain stem
Thalamus
Pair of egg shape structures that make up most of diencephalon
What are the functions of thalamus
Acts as a relay center
Relays sensory input from brainstem up to primary somatic sensory cortex
Can amplify or dampen sensory input
Relay motor output from primary motor cortex through brain stem
Hypothalamus
Inferior to thalamus
acts as a visceral control center of the body
What is the hypothalamus In control of
Controls autonomic functions like your heart rate
regulates body temperature
regulates hunger and thirst
regulates circadian rhythm controls emotions as part of limbic system regulates hormone production via pituitary gland
Pituitary gland
Secrete multiple regulatory hormones that coordinate other endocrine glands
Epithalamus
Most dorsal part of diencephalon
Consists of pineal gland which secretes melatonin
Brainstem
Inferior to cerebrum anterior to cerebellum
Connect Cerebrum and cerebellum to spinal cord
What is the brain stem function
Acts as relay center between brain and spinal cord
Serve as origin for most cranial nerve
Midbrain
Most superior part of brain stem

Mid brain
cerebral peduncles
Two ventricle pillars that hold up cerebrum
Contain motor axons for cerebrum to medulla oblongata
Pons
Middle portion of brain stem
bulge separated from cerebellum by fourth ventricle
serves as relay sensors for cerebellum
Medulla oblongata
Most inferior portion of brainstem that directly connects to spinal cord
Medulla oblongata
Pyramidal tracts 
 Nerve fibers that descend to cerebrum and carry voluntary output to spinal cord
Decussation of the pyramids
Crossing of nerve fibers
Each Cerebral hemisphere sends motor commands to contralateral side of body
Cerebellum
Second largest part of brain
Inferior to occipital lobe
coordinates in balance
Vermis
Narrow band cortex between the two hemisphere of cerebellum
White matter in the cerebellum
Branches out into a pattern called a bore vitae (tree of life)
Cerebellar nuclei 
Deeply situated Grey matter
gives rise to axon that relay instruction from cerebellar cortex to other parts of the brain
Important in muscle memory helps to refined and smooth out body movements
Limbic system
Along the border between cerebrum and diencephalon
 Limbic lobe
Control emotional response to stimuli linked to prefrontal cortex which explains why there is a close relationship between feeling in thinking
Fornix
Fiber tracks that connect different parts of limbic system
Limbic system
Hypothalamus and thalamus
Links of motion of visceral functions in brain stem explains why strong emotions can have visceral response like elevated heart rate
Amygdala
Processes fear links emotion to memory is useful for making decisions based on past experiences
Hippocampus
Stores in retrieves long-term memories
Reticular activating system
Netwerk of neurons that help connect various parts of the body
Reticular formation
Runs through central core of brainstem and Projects through thalamus and central cerebrum
Reticular activating system
Part of reticular formation
controls brain consciousness in alertness ascending axons from all major sensory tracts synapse in the pons and medulla, Visual auditory touch stimuli keeps people awake
Descending axons influenced somatic motor neurons, we have decreased muscle tone when sleeping
Spinal cord
Cylinder of nerves extending to brainstem to upper lumbar region contact information between brain and rest of body
At It superior end it connects to the _____ in travels through the ___ Of the occipital bone into the vertebral canal
Brain stem/ foramen magnum
Spinal nerves
Bundles of nerve fibers that arise from the spinal cord at various levels
Dorsal root
Posterior root that provide sensory input
Dorsal root ganglion
Cluster of nuclei
Ventral root
Anterior root delivers motor output
Conus medullaris
Inferior end of spinal cord
between L1 and L2
Filum terminale
Thin filament of connective tissue that extends from conus medullaris
 attaches Conus Medullaris To the coxal and helps hold it in place
Caude equina
Cluster of spinal nerves that extend inferior to conus medullaris
Spinal cord is shorter than vertebral column partly because of pre-natal event the spinal cord grows more slowly than vertebral column
Between what vertebrae can lumbar punctures be safely performed
Below L1 and L2
 where does the spinal cord have white and gray matter
Has white matter on the outside and gray matter on the inside
Green matters around central canal and arranges in H shaped masses called horns
Dorsal horn
Contain sensory neurons which receive input from neurons whose cell body lies in dorsal root ganglion
Ventral root
Contain motor neuron that send axon out via ventral root
Columns and tracks
Nerve fibers that travel up and down spinal cord
Dorsal/posterior columns
Ascending tracts
relay sensory information up to brain
Ventral/ anterior columns
Descending tracts
Conduct motor command down to muscles
