what are the commissural fibers?
connects the two hemispheres
what makes up the commissural fibers?
what are the association fibers?
connections in the same hemisphere
association fibers will divide into what 2 types?
Also, what will they connect?
1) short: connects adjacent gyri (arcuate fibers)
2) long: connects different lobes
what are the major associations fibers? what will each connect?
- superior longitudinal fasciculus: connects frontal, parietal, occipital lobes
- arcuate fasciculus: connects the temporal lobe, also Wernicke's and Broca's
- Cingulum: connects cingulate gyrus to other limbic structures
what are projection fibers?
what is another name for these?
fibers that ascend or descend to brainstem or spinal cord
also called subcortical
what are the 2 types of projection fibers? in which direction do they go?
which is sensory and motor?
- coriticopetal: towards the cortex
2. corticofugal: from the cortex
what are the 4 examples of corticofugal (type of projection fiber) fibers?
which ones are the only that go anterior?
which one goes posterior?
1) Corticospinal to spinal nerves
2) Corticobulbar/nuclear to cranial nerves
3) Corticostriate and Corticopontine
4) extrapyramidal tracts (corticorubral)
Corticostriate and cortipontine; corticospinal and corticobulbar go through the anterior limb
extrapyramidal tracts go through the posterior limb
what type of neurons use the coriticopedal type of projection fibers?
3rd order neurons from the VPL and VPM that are going to the cortex
on their way they go through the posterior limb
what are the parts of the corpus callosum?
which fiber connects Broca's to Wernicke's?