Create an account
The white matter underlying the cortex consists of myelinated axons running in three directions, association fibers (within the same hemisphere), commissural fibers (between hemispheres), and projection fibers. Projection fibers are ascending and descending tracts that transmit impulses from the cerebrum to other parts of the lower brain and spinal cord. Commissural fibers transmit impulses from one cerebral hemisphere to the opposite cerebral hemisphere. In slide 1, the three important groups of commissural fibers are shown; the corpus callosum (in yellow), the anterior commissure (in red), and the posterior commissure (in blue).
Please allow access to your computer’s microphone to use Voice Recording.
Having trouble? Click here for help.
We can’t access your microphone!
Click the icon above to update your browser permissions and try again
Reload the page to try again!Reload
Press Cmd-0 to reset your zoom
Press Ctrl-0 to reset your zoom
It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.
Please upgrade Flash or install Chrome
to use Voice Recording.
For more help, see our troubleshooting page.
Your microphone is muted
For help fixing this issue, see this FAQ.
Star this term
You can study starred terms together