L2 - structure of the nervous system Flashcards
3 different scales to view the brain
macroscopic
mesoscopic
microscopic
how many neurons in the brain
86 billion
macroscopic scale
looks at flow of connections
uses tractography
looks at general structures
mesoscopic scale
looks at divisions of functional compartments and their functions
microscopic
looks at functions of single cells
anatomy and characteristics of neurons
where is visual cortex
back of brain in occipital lobe
Raman Y Cahal
neuroanatomist
used golgi stain
detailed brain morphology
e.g. purkinje cell
synaptic strength/plasticity underlies…
- processing of sensory information
- motor circuits
- memory formation
defects/loss of synapses leads to…
dementia, paralysis etc
astrocytes
wrap around synapses
mop up excess neurotransmitter
what is self-avoidance, exlpain process
- neuron projections never synapse back on themselves
- they recognise their own projections
what does glia mean
glue
function of glial cells
regulation of synapses trophic support protection of neurons maintain homeostasis form myelin
two examples of gliotransmitters
ATP
D-serine
4 types of gilal cell
oligodendrocyte
microglia
astrocyte
ependymal cell
oligodendrocyte
MYELIN SHEATH
wrap myelin sheath around neurons - support and insulation
microglia
BRAIN IMMUNE CELLS
modulate activity - synaptic pruning
phagocytose cell debris
synaptic pruning
elimination of synapses in development
astrocytes
ENERGY BALANCE
provide nutrition for neurons star-shaped most abundant maintain BBB absorb and recycle neurotransmitters
EPENDYMAL CELLS
CSF
line CSF-filled ventricles
similar to ciliated epithelial cells
assist in circulation, producing and monitoring CSF
human cerebral cortex map
1909 Brodmann
importance of 1909 Brodmann cerebral cortex map
widely used
Brodmann = pioneer
shows grouping of neurons ‘structural and functional’relationships
cyto-archi-tech-tonics
study of cellular composition
stains reveal location of neurons
components of tripartite synapse
1 - pre-synaptic terminal nerve
2- post-synaptic spine
3 - glial cell
3 features looked at and combined in modern brain mapping
function
architecture
connectivity
technique - modern mapping of brain function
task-based MRI
technique used in modern mapping of brain architecture
myelin mapping
technique used in modern mapping of brain connectivity
resting state fMRI
fMRI
Functional magnetic resonance imaging
