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“Memorize The Types Of Fibers Of The Cranial Nerves In 10 Minutes So
That You Can Write Them Out In Less Than 60 Seconds:
A Visuo‐SpaIal Approach With a Long Title”
by Ethan Beckley
First memorize a simple mnemonic:
“Some say marry money, but my brother says big brains maPer more.”
If you already know this mnemonic and understand how to use it you
can skip the next page.
First memorize a simple mnemonic:
“Some say marry money, but my brother says big brains maPer more.”
Here’s how you use the mnemonic:
There are twelve words of the sentence which each correspond to one
of the twelve cranial nerve pairs.
The first lePer of each word tells you whether the nerve associated with
that word conveys sensory informaIon, motor informaIon, or both
sensory and motor informaIon.
Nerve Mnemonic word Type of information
01 - Olfactory Some Sensory
02 - Optic Say Sensory
03 - Oculomotor Marry Motor
04 - Trochlear Money Motor
05 - Trigeminal But Both
06 - Abducens My Motor
07 - Facial Brother Both
08 - Vestibulochochlear Says Sensory
09 - Glossopharyngeal Big Both
10 - Vagus Brains Both
11 - Accessory Matter Motor
12 - Hypoglossal More Motor
The next task is to re‐order the nerves according to their funcIon. Say
the mnemonic to yourself while separaIng the the nerves into different
groups based on their funcIons. Here’s a Ime‐lapse of what your paper
should look like as you separate the nerves into funcIonal groups:
1 2 8
3 4 6 11
12
5 7 9
10
1 2 8
3 4 6 11
12
5 7 9
10
1 2 8
3 4 6 11
12
5 7 9
10
1 2 8
3 4 6 11
12
5 7 9
10
1 2 8
3 4 6 11
12
5 7 9
10
1 2 8
3 4 6 11
12
5 7 9
10
1 2 8
3 4 6 11
12
5 7 9
10
1 2 8
3 4 6 11
12
5 7 9
10
1 2 8
3 4 6 11
12
5 7 9
10
1 2 8
3 4 6
11 12
5 7
9 10
1 2 8
3 4 6 11
12
5 7 9
10
1 2 8
3 4 6 11
12
5 7 9
10
Some
say
marry
money
but
my
brother
says
big
brains
matter
more
You should now have numbers 1‐12 arranged non‐consecuIvely on
your piece of paper in groups. It should look something like this:
The next job is to turn this list into a table.
1 2 8
3 4 6
11 12
5 7
9 10
Write out column headings for your table. Put the sensory group before
the motor group (“look before you leap”).
The sensory set is: Special Sensory, SomaIc Sensory, Visceral Sensory.
The motor set is: Branchial Motor, SomaIc Motor, Visceral Motor.
(Your table does not need all of these lines. Do what works for you.)
Group Nerve Special"Sensory
Somatic Sensory
Visceral Sensory
Branchial Motor
Somatic Motor
Visceral Motor
Sensory 1
2
8
Motor 3
4
6
11
12
Both 5
7
9
10
The last task is to be able to fill in the table visually. Here I have shaded
the boxes to indicate which fibers are found in which nerves.
The trick is to memorize the image itself, not what the image tells you.
Learn what the table looks like. It looks like the table below! Learn the
paPern and shape of the shading.
Once you know what the table looks like you should be able to recreate
it from memory.
Group Nerve Special"Sensory
Somatic Sensory
Visceral Sensory
Branchial Motor
Somatic Motor
Visceral Motor
Sensory 1
2
8
Motor 3
4
6
11
12
Both 5
7
9
10
But when you go to recall the informaIon you don’t need to make quite
such a fancy table. Here is the same informaIon in a form that you can
write out in literally 60 seconds (with pracIce) and have all the data you
need.
Sp S! Som S! Vis S! Br M! Som M! Vis M!
1! ✓
2! ✓
8! ✓
3! ✓ ✓
4! ✓
6! ✓
11! ✓
12! ✓
5! ✓ ✓
7! ✓ ✓ ✓ ✓
9! ✓ ✓ ✓ ✓ ✓
10! ✓ ✓ ✓ ✓ ✓
To summarize the steps:
Write out numbers 1‐12 in three groups according to the funcIons of
nerves 1‐12 (use the mnemonic).
Write out column headings le_ to right: Sensory (special, somaIc, and
visceral) then motor (branchial, somaIc, and visceral).
Fill out the table with check boxes based on your mental image of how
the table should look:
• Three check marks on the le_ side of the sensory group
• A flipped “L” shape on the right side of the motor group
• An up/down paPern (3‐4‐2‐4‐0‐4) in the “both” group
That concludes the memorizaIon method, but here are some bonus
observaIons that might interest you.
Sp S Som S Vis S Br M Som M Vis M
1 ✓ Using a spatial representation of the information it quickly becomes
obvious that the cranial nerves that are sensory-only all use special
sensory fibers exclusively. They don’t muck around with somatic or visceral sensory fibers.
2 ✓
8 ✓
3 ✓ ✓
4 ✓
6 ✓
11 ✓
12 ✓
5 ✓ ✓
7 ✓ ✓ ✓ ✓
9 ✓ ✓ ✓ ✓ ✓
10 ✓ ✓ ✓ ✓ ✓
Sp S Som S Vis S Br M Som M Vis M
1 ✓
2 ✓
8 ✓
3 It also becomes clear that motor-only neurons tend to
use somatic (voluntary) motor fibers as their
exclusive fiber type.
The only exception is cranial nerve 3, the oculomotor
nerve. Since pupil dilation is not under voluntary
control, we can surmise that pupil dilation is controled
by cranial nerve 3.
✓ ✓
4 ✓
6 ✓
11 ✓
12 ✓
5 ✓ ✓
7 ✓ ✓ ✓ ✓
9 ✓ ✓ ✓ ✓ ✓
10 ✓ ✓ ✓ ✓ ✓
Sp S Som S Vis S Br M Som M Vis M
1 ✓
2 ✓
8 ✓
The only lesson that I have learned from inspecting
the “both” section is related to CN 5.
The trigeminal nerve goes all over the face. Yet the
table reveals that it does not have special or visceral
sensory functions, nor does it have visceral motor
functions. From these findings we can conclude that
despite its ubiquity around the mouth, it does not provide taste sensation (Sp S), tongue movement
(Som M), or salivation (Vis M).
3 ✓ ✓
4 ✓
6 ✓
11 ✓
12 ✓
5 ✓ ✓
7 ✓ ✓ ✓ ✓
9 ✓ ✓ ✓ ✓ ✓
10 ✓ ✓ ✓ ✓ ✓
