Sensory and Motor Anatomy – Afferent vs Efferent
By Haley Masterson
Afferent vs Efferent. “Afferent” and “Efferent” may be among the most confusing similar-sounding words in medicine. Luckily, there’s a mnemonic to help tell them apart. And, as a bonus, this study trick also covers the difference between dorsal and ventral neurological systems.
This basic system is present throughout spinal cord anatomy – dorsal roots carry afferent fibers, and ventral roots carry efferent fibers. Similarly, the ventral horn contains efferent cell bodies, and the dorsal root ganglion contains afferent cell bodies. (Remember that the white matter contains myelin and is therefore where you can find axons. The cell bodies will be located in the gray matter.)
Which ones are afferent vs efferent? Just remember the “SAD” part of “SAD DAVE”:
Sensory = afferent (which is Dorsal) – meaning that the ventral “efferent” fibers must carry motor information.
Rx Bricks: Anatomy of the Spinal Cord