lecture 10/11 Flashcards
meninges
- are tissue mebranes that lie between bones and soft tissues of the CNS
- protect and cushion the brain and spinal cord
the CNS is made up of
brain and spinal cord
Name the 3 tissues that make up the meninges of the brain
- dura mater
- arachnoid membrane (fluid filled)
- pia mater (thinest layer)
what fills the subarachnoid space
cebrebrolspinal fluid (CSF)
ventricles produce _______ at the ___________
- cerebrospinal fluid
- choroid plexus (meeting of the capillaries and ependymal cells)
Functions of CSF
Physical and chemical protection:
- provides buoyancy and absorbs shock, we dont want to much CFS cause pressure will build up
- deliver (nutrients like glucose and oxygen) and remove waste (CO2)
name one major difference between plasma and CSF
the lack of protein in CFS
CSF production
ependymal cells will selectivly transport solutes (ex. glucose —-> transcellular) and then water follows by osmosis
- make it at ependymal cells within ventricles that act as border control that regulates what can come in and what cannot
CSF absorption
CSF is absorbed from the subarachnoid space into venous circulation by the arachnoid villi
the 2 aspects of the blood-brain barrier
- the ependymal cells make up and important part of the BBB where CSF is produced at choroid plexus within the ventircles
- the astrocyte foot processes secrete paracrine which promote up regulation of tight junctions which causes lining of capillaries to link more tightly —-> no leaks!
metabolic needs of neurons and glial cells
- oxygen
- nutrients: glucose or ketone produced by the liver when carbs are low
how do oxygen and glucose cross the blood-brain barrier?
oxygen: diffusion
glucose: transcellular or glucose transporter in ependymal cells
white matter
- fats
- tracts of myelinated axon fibers
grey matter
- everything else
- dendrites, synapses, cell bodies
gray matter of the spinal cord
dorsal=sensory=afferent (incoming information —> to brain)
ventral=motor=efferent (outgoing information —> info coming from the brain leaving ur spinal cord)
white matter on the outside
white matter i’m the spinal cord
ascending tracts: bundles of axons carrying messages from the spinal cord to the brain
descending tracts: bundles of axons carrying messages from the brain to the spinal cord
the brain stem
consists of the medulla, pons and midbrain
- evolutionarly speaking its pretty ancient
- autonomic function: breathing, heartrate and swallowing (medulla and pons)
- relay station for pathways (pons)
- auditory pathways and eye movements (midbrain)
How many cranial nerves are there
12
cranial nerves originate from
the brainstem
basal ganglia
- gray matter
- important for preventing movement when you do not want to move
- ensuring movement is smooth
name 2 conditions that involve the basal ganglia
- parkinsons disease
- huntingtons disease
The cerebral cortex
- Frontal lobe:
premotor cortex –> you being you, descision making, writing, smiling or speaking - Parietal lobe:
sensory cortex: incoming sensory information, what you perceive - Occipital lobe: visual cortex
- Temporal lobe: auditory cortex (hearing) and gustatory cortex and olfactory cortex (non-verbal information)
Thalamus
- receives sensory and motor information
- projects fibers to cerebrum for info processing
hypothalamus
homeostasis and behavior
pituitary gland
anterior: secretes hormones
posterior: secretes neurohormones that are made in the hypothalamus
pineal gland
secretes melatonin and regulates sleep cycle
centers for emotion, memory and learning
- cingulate gyrus
- hippocampus ( learning + short term)
- amygdala (emotion)
the limbic system
- lies around brainstem
- links higher, cognitive regions of the cerbellum to more primitive functions
- center for emotion, learning and memory
The cerebellum
- rate, range, and force
- overseas a movement and make sure it is executed as intended
- compares executed to intended
wernicke’s area
language understanding center (verbal or written)
broca’s area
responding verbally
Damage to Wernicke’s area
receptive aphasia
loss of understanding, but expression (without meaning) is maintained
Damage to Broca’s area
expressive aphasia:
loss of verbalization, but they can understand you perfectly fine
