Cranial Nerves Mnemonic – Easy Way To Remember 12 Cranial Nerves

Like the human roads that facilitate movement from point to point initiating delivery, the nervous system consists of the central nervous system.

It is made of the brain and the spinal cord.

While the peripheral nervous system made of cranial, spinal and the peripheral nerves alongside their motor and sensory nerves.

There is a total of twelve pairs of cranial nerves emanating from the brain rather than the spinal cord.

Their core function is to relay information between the brain and another part of the body more so in areas around the head and the neck.

Some other cranial nerves regulate the activity of the muscles. Other cranial nerves form link to the heart and the lungs.

Types of cranial nerves

The nerves are named from the posterior end to the anterior end of the brain starting with the olfactory nerve to the twelfth cranial nerve, the hypoglossal.

They are also named depending on their function.

Number Name Function (Sensory/Motor/Both)
I Olfactory Sensory
II Optic Sensory
III Oculomotor Motor
IV Trochlear Motor
V Trigeminal Both (S/M)
VI Abducens Motor
VII Facial Both (S/M)
VIII Vestibulocochlear Sensory
IX Glossopharyngeal Both (S/M)
X Vagus Both (S/M)
XI Spinal accessories Motor
XII Hypoglossal Motor
Cranial Nerves From Brain

Image- antranik.org

The olfactory cranial nerve

Top on the list is the olfactory cranial nerve. It has its origin on the olfactory mucosa.

It penetrates through the cribriform plate and makes its destination on the surface of the brain. It is the shortest of all and very special when it comes to the sense of smell.

Not only that, it has an advanced function of taste. Above all what makes it so special is that it is capable of regeneration when damaged.

It consists of olfactory receptor neurons that are responsible for transmitting smell as soon as they receive perception by the olfaction.

Optic nerves

As we descend the list, the optic nerve at position two is responsible for relaying visual senses from the retina to the brain.

It originates from optic disk and runs through the optic chiasm, optic tract, lateral geniculate nucleus and rest at the superior colliculus at the vision center of the brain.

The optic nerve has over one million nerve fiber and is made up of ganglion cells.

As we close at number two and welcome the oculomotor at number three, it is important to note that although the optic nerve is part of the eye, it is primarily considered as part of the central nervous system.

Oculomotor

The oculomotor is the third nerve cell of the cranial nerve cells.

Its origin is in the midbrain where it starts from the third nucleus located lateral to the cerebral aqueduct on the gray matter.

It passes through the tegmentum, red nucleus and emerges from the sulcus on the middle part of the cerebral peduncle.

The oculomotor consist of the general somatic afferent that stimulates the movement of the skeletal muscle of the superior medial and inferior rectus.

Besides, it has the general visceral efferent that gives preganglionic parasympathetic to the ciliary ganglion.

Trochlear

At number four we present the motor trochlear nerve.

Unique from the rest of the nerves, having the fewest number of axons, the greatest intracranial length and the only nerve that emerges from the rear part of the brain.

Above all, it is the only cranial nerve that stimulates a muscle on the opposite side from where it originates.

Just like the optic nerve, its primary function lies in the eyes. The role, this time, is not on the visual aspect of the eye but eye movement.

It stimulates the superior oblique thus turning the eye downward and lateral.

It move forward and enters the Dura matter between the free and attached cells of the tentorium cerebella.

It goes up to the cavernous sinus where it enters the orbit via the superior orbital fissure. It winds diagonally across the levator palpebrae and superior rectus muscle to stimulate the oblique muscle.

Trigeminal

From the eye, we move to the mouth where we find the trigeminal nerve responsible for chewing and pain of the mouth and face.

At number five in the list, we find the largest and very involved nerve- the trigeminal.

It provides sensation to the face, mucous membranes and other parts of the head.
It emerges from the brain consisting of a significant sensory root and a smaller sensory root originating from the Pons.

It travels laterally to meet the semilunar ganglion in the Meckel cave.
The nerve has sensory organs that provide tactile and nociceptive afferents to the face and mouth.

The nerve also has the motor organs that help in mastication.

Abducens

Responsible for turning the eye laterally, the abducens comes at number six.

It is a somatic afferent nerve that regulates the movement of a single muscle- the lateral rectus muscle of the eye.

From the brainstem, the nerve travels upward between the Pons and the clivus where it penetrates the Dura mater.

From here it enters the cavernous sinus where it goes through the internal carotid artery. It stops at the arbitral fissure where it stimulates the lateral rectus muscle of the eye causing the eye to move laterally.
Facial

The facial nerve is responsible of all of the facial expression we express through our face. The key to these feelings lies behind facial nerve.

It originates from the brainstem between the medulla and the Pons. It has the large motor root and the small sensory root. The two roots move through the internal acoustic meatus where they open in the temporal bone.

From here, the nerve exits the internal acoustic meatus and goes into the facial canal. Here the two roots fuse to create the facial nerve. Th nerve continues to form the geniculate ganglion that gives rise to the greater petrosal nerve.

The facial nerve then leaves the facial canal and turns to run through the anterior to the outer ear where it provides motor stimulation around the ear. The motor root then continues to the parotid gland that make five branches that are responsible for stimulating the muscles of the face depending on the environment outside the face.

Vestibulocochlear

To be able to oppose the force of gravity on earth and acquire balance that makes us run, walk upright, bend and sit, the vestibulocochlear at number eight claims the importance.

It is responsible for transmitting sound and equilibrium. It made mainly of the bipolar nerves that branch into the cochlea and the vestibular nerve. 

The cochlear run all the way to the inner ear where it stimulates the inner hair cells that are responsible for activating afferent receptors to respond to pressure waves that reach the basilar membrane through sound.

The vestibular nerve goes through the vestibular system of the inner ear. The vestibular ganglion has the bipolar neurons that extend to form five sensory cells. Three of them are the cristae that have hair cells that activate the afferent receptors to respond to rotational acceleration.

The other two are the maculae that stimulate the afferent receptor to respond to acceleration.

Glossopharyngeal

At number nine on our list, we encounter the glossopharyngeal nerve that is responsible for taste and sensing carotid blood pressure.

It consists of the afferent sensory nerve and the efferent motor information. From the upper medulla, the nerve travels through the skull at the jugular foramen and rest in the mouth in the mucous glands.

Here it functions to receive sensory fiber from the tongue, carotid body, the tonsil and the middle ear.

Vagus

The vagus is responsible for sensing the blood pressure of the aorta, slowing down heart rate and stimulating digestive organ tastes.

The vagus emerges from the medulla oblongata and runs through the jugular foremen and ends at the neck, chest, and abdomen where it stimulates the viscera.

Besides, the vagus has afferent nerves that relay information about the state of the body to the central nervous system.

Spinal accessories

The nerve provides the sternocleidomastoid and the trapezius muscles.

The two muscles are responsible for the movement of the head away from the side the sternocleidomastoid muscles contracts, elevation of the shoulder through the action of the trapezius and drawing the head back thus keeping the face upward by the trapezius muscle.

Hypoglossal

At number twelve the hypoglossal closes the list with its stunning function of controlling the tongue movement.

The nerve emerges from the hypoglossal nucleus in the medulla oblongata of the brain. It then travels through the posterior cranial fossa.

The nerve then exits the cranium through the hypoglossal canal.

From here the nerve receives a branch of the cervical plexus that generate fibres from C1 AND C2.it then crosses the internal and external carotid arteries and terminating in the anterior direction and enters the tongue.

Cranial Nerves Mnemonics –

Here are some useful mnemonics that will help you to easily remember the cranial nerves.

1.

Cranial Nerves Mnemonic

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Cranial Nerves Mnemonics

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Cranial Nerves Mnemonics

 

 

Best Stethoscope Reviews -How To Choose a Best Stethoscope Easily

It can be a very daunting process to choose the best stethoscope for all your medical studies, clinic or even other purposes.

There are many stethoscopes in the market nowadays thus it can be a little bit difficult to find a single stethoscope and then call it the best.

As a matter of fact, it would very fair to say that there are several awesome stethoscopes available in the market because many professionals use them to perform many functions.

However, you no longer have to worry about finding the best product since we have finalized an in-depth research to provide you with the best stethoscope reviews so as to assist you in choosing the right stethoscope.

When purchasing this essential instrument for your medical career, it is imperative to get a stethoscope which does not just work, but it makes auscultation a better experience both for you and patients as well.

Choosing the appropriate stethoscope can optimize your patient care and you will be having the precise tool that will assist with accurate diagnoses throughout your career.

A poorly crafted stethoscope, on the other hand, can lead to numerous replacements or even unknowingly provide inaccurate auscultations of your patients.

Here are the things to look for when buying a stethoscope:

CHESTPIECE

You should look for a complete construction of stethoscope with high-density materials like stainless steel or even titanium.

Harder materials shall conduct better sound as compared to softer and more porous metals like aluminum.

In addition, the chest piece should have a hand-polished finish both on the outside and inside as well.

HEADSET

Optimally, the headset ought to have a similar high-density material as that of the chest piece and it should be angled at 15 degrees as a standard.

Just as one would want to have the highest amplifying and sealing acoustics on the chest piece, you will also want the same high-quality metals to transmit the sounds to the headset.

Nevertheless, be cautious on the materials which are used for both chest piece and headset since the description of the stethoscope might only include the chest piece material.

DIAPHRAGM

You should look for a durable and high-quality diaphragm.

It will be advantageous for you to have extra just in case of punctures or other mishaps.

TUBING

You must select a stethoscope which has durable and thick tubing so as to isolate the acoustics from the external noise and also insulate the sounds.

Thin tubing or tubing which is prone to breakage might lead to the loss of sound.

Tubing should be longer enough to maintain a safe distance from the patient.

Sound can be compromised using longer tubing, so ensure that you find a stethoscope which can compensate this length with thicker tubing together with headsets and chess pieces made from quality metals.

EARTIPS

Ear tips might seem like an afterthought whenever one is selecting a stethoscope.

However, they are actually crucial in providing precise readings.

Ear tips must fit comfortably and securely inside the ear and they should preferably be offered in several sizes for comfort.

The ear tips should not only be comfortable but should also create a seal inside the ear so as to prevent the external sound from seeping through.

STEM

The stem on your stethoscope also makes a big difference!

For the most premium sound experiences, you will want a stem which has been constructed using same quality metals as your chest piece.

Do not overlook this little detail because a great stem should be precisely designed and has to “snap” into the right place so as to reduce sound leakages.

Below is the few popular stethoscope reviews:

LITTMANN CLASSIC II SE REVIEW

With a weight of about 317.5 grams, the Littmann Classic II SE stethoscope is a great instrument that you can have.

As a matter of fact, it has been used by a wide range of people in healthcare industry thanks to its comfort and high-quality materials.

If you do not like the pricey costs of the Cardiology III, then this is a stethoscope which can be a better option for limited budgets.

The Littmann Classic II SE’s best features are:

  • Patented tunable diaphragm. Bearing in mind that this is a 3M product, the instrument has a patented tunable diaphragm so as to give you better acoustics while using the stethoscope with your patients. Its sound intensity can also be adjusted in order to listen to low as well as high-frequency sounds clearly.
  • Comfort for the patients. Unlike other stethoscopes in the market, this instrument has a non-chill rim on the bell and diaphragm. This shall surely make the patient more comfortable while trying to hear some crackles and murmurs.
  • Excellent acoustic seal. Besides the comfort that it brings, the stethoscope comes with soft-sealing ear tips which make sure that you will have maximum comfort when listening.
  • Can be personalized. The tubing on the Littmann Classic II SE can be personalized simply by placing your name on its tube. By doing so, your name will be visible to both your patients and co-workers as well.
  • Free of latex. The stethoscope is great for people who are allergic to latex.

LITTMANN CARDIOLOGY III REVIEW

The Littmann Cardiology III is not only suitable for children but also for adults. Among the wide range of stethoscopes in the cardiology department, this is the only stethoscope one which comes together with a dual-sided chest piece.

It also has patented tunable diaphragms which can be used in listening to low as well as high-frequency sounds. With its two tubes, the stethoscope eliminates noise which is created when the tubes are rubbed together.

The Littmann Cardiology III best features are:

  • Tunable diaphragm technology. This is a technology which can only be found in selected stethoscopes. With this technology, you are capable of adjusting its pressure on the chest piece so as to listen to different frequency sounds. By doing so, it allows you to focus on the patient without necessary making him uncomfortable while you are trying to hear his heart beat or even breathing.
  • Adjustable headset. With the adjustable headset, the stethoscope can fit easily into your ears for a very comfortable fit and an excellent seal for great hearing. Its tips are also firmly snapped for safety reasons.
  • Flexible tubing. Even if you choose to tightly fold it, the tubes shall still retain its flexibility and shape. As a result, the stethoscope lasts longer. It is ideal if you’re sensitive to latex because it isn’t made from natural rubber latex and does not also contain phthalate plasticizers.
  • Available in several colors. You can choose from purple, brown, black, gray and chocolate.

Despite being an excellent option, the stethoscope it can be quite heavy. As a result, you might not be capable of wearing it around the neck for a long time. Nevertheless, it is one of the stethoscopes which you can own should you wish to hear crackles and murmurs clearly and easily.

ADC ADSCOPE 603 STAINLESS STETHOSCOPE REVIEW

Do you need a stethoscope which would cost less than 100 dollars? In case you do, then the ADC ADSCOPE 603 STAINLESS STETHOSCOPE an excellent option. Even though you still have to pay for the shipping cost, the added expenses are still worth the investment when you consider its list of great features.

Weighing only 1 pound, the stainless steel product has been made with doctors in mind. Through the professional-grade quality, all workers from the healthcare industry can take advantage of its great features that include.

  • A lifetime warranty. This is one of the very few options in the market that offers lifetime warranties.
  • An ergonomic design. Even after an extended usage, the stethoscope still gives you comfort. It is comfortable not only for doctors but also patients
  • Durable chest piece. The stethoscope has a stainless steel dual-head chest piece which has been hand-polished so as to ensure that it offers you highest performance and excellent durability.
  • Made with thicker and non-stick acoustic tubing. This prevents wearing and cracking from repeated usage. The non-stick tubing also offers insulation which seals out noise from surroundings.
  • The acoustic pyramid chamber. This is a patented chamber which allows the tubing channel to open so that you can clearly hear the sound all the time.
  • ComfortSeal ear tips. The stethoscope has this patented feature which ensures comfort fit. In addition, it makes the stethoscope more durable and last for several years.
  • Comes with accessories. The accessories include the ultrasensitive diaphragm and the extra set of ear tips.

Even though it is not as pricey as the other stethoscopes in the market, the cheaper price should not be a reason for you to ignore this option. It is a lot lighter when compared to other options. This is a very great thing more so for individuals who do not wish to carry a heavy load in their necks.

LITTMANN MASTER CLASSIC REVIEW

Nursing professionals who are looking for a top-notch diagnostic tool shall find the Littmann Master Classic Stethoscope to be a great choice for all physical assessments.

Amongst the Littmann stethoscopes, the Littmann Master Classic is perfectly suited for entry level nurse, certified nursing assistants, licensed vocational nurses, EMTs, medical assistants, registered nurses and nursing students.

Several medical professionals have given the stethoscope 5 stars in their reviews while praising its ease of use, its comfortable fit as well as the excellent acoustics.

This ergonomically-designed stethoscope has a weight of over 5 oz and it is 27 inches long. This gives you an extra length during the patient exams.

The instrument also features a tunable diaphragm which allows you to listen to high and frequencies. The headset also comes while equipped with the soft sealing ear tips. In addition, you also have the freedom of choosing your favorite color from the 13 possible choices available. Among the Littmann Master Classic’s best features are:

  • The tunable technology which allows you to conveniently hear both the low and high-frequency sounds while examining patients. This is done by easily applying firm or light pressure to its chest piece. This is contrary to other stethoscopes where you would have to turn the chest piece so as to perform this same procedure.
  • The headset on this tool is designed for very high-performance sound transmissions and it can be flexed several times during examinations. The headset is also durable enough to be flexed more than one million times thus allowing it to provide long-lasting services.
  • The snap-tight and soft sealing ear tips also provide both a very comfortable fit as well as an acoustic seal thus blocking out environmental sounds which might negatively influence the diagnosis. This is particularly helpful while in noisy situations.

 

OMRON SPRAGUE RAPPAPORT REVIEW

The Omron Sprague Rappaport is the best stethoscope for students given the fact that it is cheap.

As a student, you’re just learning what you have to be listening for and it’s more important for you to spend your money on the best courses and books than on the high-end stethoscopes.

In addition, you also have to consider the fact that it’s very likely that you shall misplace, lose or even forget at least a few stethoscopes until you get to practice medicine on your own. As a result, there’s no point for you to spend too much money on any stethoscope.

The Omron Sprague stethoscope is a decent stethoscope given the fact that Omron is among the biggest names in medical accessories’ market.

They aren’t specifically focused on producing stethoscopes but with this Sprague, they’ve managed to create an impressive product.

The stethoscope uses the standard 2 tube configuration that has the benefits of providing direct sound paths for each ear tip to the diaphragm. Of course, the Littmann built their tube configuration for a very good reason. However, the way in which the Omron stethoscope binds the 2 tubes together and also sound proofs them with the latex free tubing also achieves a great result.

Therefore, which is the best stethoscope?

The fact that the ultimate decision which might save a person’s life rests in the doctor’s hands also means that the best stethoscope to be used by doctors has to be the very best stethoscope that currently exists in the market; the Littmann Cardiology III.

This is one of the expensive stethoscopes. However, it is flawlessly built and designed to make it well worth that money.

The stethoscope is dual sided making it a perfect choice for pediatricians and the general practitioners as well. Both diaphragms are well-designed to respond to pressure changes so as to allow one to listen to low as well as high frequencies.

And what’s, even more, important is the mere fact that its sensitivity level is unmatched when compared to other products in the market.

CONCLUSION

A stethoscope is a primary tool which every nurse and physician must have. Individuals working in the healthcare industry cannot complete or even perform their responsibilities without a quality stethoscope.