Ascending Tracts | Spinocerebellar Tract

Summary

This educational video script delves into the intricacies of the spinocerebellar tracts, crucial pathways linking the spinal cord to the cerebellum for proprioception, touch, and pressure sensations. It details the dorsal spinocerebellar tract (DST), ventral spinocerebellar tract (VST), cuneocerebellar tract, and the spinal oliveri tract, highlighting their unique pathways, receptors, and functions in maintaining posture, balance, and muscle coordination. The script also explains the distinction between climbing and mossy fibers, essential for understanding cerebellar inputs.

Takeaways

• 📚 The video discusses the spinocerebellar tracts, which are pathways in the nervous system that carry sensory information from the spinal cord to the cerebellum.
• 🔍 It's recommended to watch videos on the dorsal column medial meniscal pathway, the spinothalamic pathway, and pain modulation before this one for a comprehensive understanding.
• 🌟 The script introduces three main spinocerebellar tracts: the dorsal spinocerebellar tract (DST), the ventral spinocerebellar tract (VST), and the cuneocerebellar tract.
• 🦵 The primary stimulus for these tracts is proprioception, which is the sense of body position and movement, crucial for the cerebellum's role in posture, balance, muscle tone, and coordination.
• 💡 Proprioceptive information comes from specialized receptors like muscle spindles, Golgi tendon organs, and also includes sensations from touch and pressure receptors.
• 🏋️‍♂️ The dorsal spinocerebellar tract (DST) originates from the dorsal root ganglion and ascends through the spinal cord to the cerebellum, with a key nucleus being Clark's column.
• 🔄 The ventral spinocerebellar tract (VST) carries information from below L3 and crosses over to the contralateral side, ascending through the spinal cord and using the superior cerebellar peduncles to reach the cerebellum.
• 🧠 The cuneocerebellar tract is responsible for sensations from the upper limbs, head, and neck, and it synapses in the accessory cuneate nucleus before reaching the cerebellum.
• 🌱 The spino-olivary tract is unique as it synapses first in the inferior olivary nucleus before crossing to the cerebellum, with fibers known as climbing fibers.
• 🌿 Other fibers entering the cerebellum from the spinocerebellar tracts, except those from the spino-olivary tract, are called mossy fibers.
• 👍 The video encourages viewers to like, comment, subscribe, and support the channel through social media and Patreon to help create high-quality educational content.

Q & A

What are spinocerebellar tracts?

Spinocerebellar tracts are pathways in the central nervous system that transmit proprioceptive information from the spinal cord to the cerebellum. They are essential for the cerebellum to control posture, balance, muscle tone, and coordination of muscle movements.

What are the main types of spinocerebellar tracts discussed in the script?

The main types of spinocerebellar tracts discussed are the dorsal spinocerebellar tract (DST), the ventral spinocerebellar tract (VST), the cuneocerebellar tract, and the spino-olivary tract.

What is the primary stimulus for spinocerebellar tracts?

The primary stimulus for spinocerebellar tracts is proprioception, which is the sense of the body's position in space and the awareness of limb and trunk movements.

What is proprioception and why is it important for the cerebellum?

Proprioception is the unconscious awareness of one's position of their limbs or trunk in space. It is important for the cerebellum because it allows the cerebellum to maintain posture, balance, and coordinate muscle movements accurately.

What is the role of muscle spindles in proprioception?

Muscle spindles are sensory receptors in muscles that detect changes in muscle length and tension. They play a crucial role in proprioception by sending signals to the central nervous system about the body's position and movement.

How does the dorsal spinocerebellar tract ascend to the cerebellum?

The dorsal spinocerebellar tract ascends through the lateral white column of the spinal cord, passes through the inferior cerebellar peduncles, and terminates in the cerebellar cortex.

What is unique about the ventral spinocerebellar tract's pathway?

The ventral spinocerebellar tract is unique because it crosses over to the contralateral side of the spinal cord via the anterior commissure and ascends through the superior cerebellar peduncles before reaching the cerebellum.

What is the function of the accessory cuneate nucleus in the cuneocerebellar tract?

The accessory cuneate nucleus is a part of the medulla where the cuneocerebellar tract synapses before the fibers ascend to the cerebellum through the inferior cerebellar peduncles.

What are the two types of fibers that enter the cerebellum from the spinocerebellar tracts?

The two types of fibers that enter the cerebellum are climbing fibers, which come from the inferior olivary nucleus, and mossy fibers, which come from the other spinocerebellar tracts.

Why is it important to understand the different pathways of spinocerebellar tracts?

Understanding the different pathways of spinocerebellar tracts is important for comprehending the complex neural mechanisms that underlie motor control, coordination, and the body's sense of position and movement.

How does the spino-olivary tract differ from other spinocerebellar tracts?

The spino-olivary tract differs in that it first synapses in the inferior olivary nucleus before crossing the midline and entering the cerebellum through the inferior cerebellar peduncles, and its fibers are referred to as climbing fibers.

Outlines

00:00

📚 Introduction to Spinocerebellar Tracts

The video script introduces the topic of spinocerebellar tracts, which are pathways conveying proprioceptive information from the body to the cerebellum. It suggests watching related videos on the dorsal column medial meniscal pathway and the spinothalamic pathway for a comprehensive understanding. The script mentions several spinocerebellar tracts, including the dorsal spinocerebellar tract (DST), ventral spinocerebellar tract (VST), and cuneocerebellar tract, emphasizing their importance in proprioception and coordination.

05:02

🧠 Detailed Exploration of Dorsal Spinocerebellar Tract

This paragraph delves into the dorsal spinocerebellar tract, explaining its role in proprioception and its pathway from the spinal cord through specific nuclei, such as Clarke's column, to the cerebellum. It describes the tract's first- and second-order neurons, their locations, and how the information ascends through the white matter to reach the cerebellar cortex via the inferior cerebellar peduncles.

10:04

🔄 Ventral Spinocerebellar Tract's Pathway and Function

The ventral spinocerebellar tract is highlighted in this section, focusing on its unique pathway that carries proprioceptive information from below L3. The tract's first-order neuron is in the dorsal root ganglion, and it crosses to the contralateral side, ascending through the spinal cord and eventually reaching the cerebellum via the superior cerebellar peduncles. The paragraph clarifies the differences between the dorsal and ventral tracts in terms of their pathways and termination sites.

15:06

🌐 Cuneocerebellar Tract and Its Sensory Contributions

The cuneocerebellar tract is discussed, emphasizing its role in conveying proprioceptive, touch, and pressure sensations from the upper limbs and head. The tract's pathway is described, from the peripheral process to the central process in the dorsal gray horn, and its ascent to the accessory cuneate nucleus in the medulla. The tract's fibers, known as external arcuate fibers, are highlighted as they pass through the inferior cerebellar peduncles to reach the cerebellar cortex.

20:07

🌿 Spino-Olivary Tract and Climbing Fibers

This paragraph introduces the spino-olivary tract, which is unique for its connection to the inferior olivary nuclei in the medulla. The tract carries a variety of sensory inputs and is characterized by its climbing fibers that cross the midline and ascend to the cerebellum via the inferior cerebellar peduncles. The distinction between climbing fibers and mossy fibers, which are associated with other spinocerebellar tracts, is explained.

25:09

🎉 Conclusion and Engagement Invitation

The script concludes by summarizing the key points about spinocerebellar tracts and encourages viewers to engage with the content by liking, commenting, and subscribing. It also invites viewers to follow the creator's social media accounts and consider supporting the channel through Patreon to help produce high-quality educational content.

Keywords

💡Spinocerebellar tracts

Spinocerebellar tracts are a set of neural pathways that transmit information from the spinal cord to the cerebellum. They are crucial for the integration of sensory input with motor control. In the video, these tracts are the central theme, with discussions on their function in proprioception, touch, and pressure sensation.

💡Dorsal spinocerebellar tract (DST)

The dorsal spinocerebellar tract, often abbreviated as DST, is one of the specific spinocerebellar tracts mentioned in the script. It carries sensory information from the body to the cerebellum and is involved in the processing of proprioceptive signals. The script describes its pathway from the spinal cord through Clark's column and its termination in the cerebellar cortex.

💡Ventral spinocerebellar tract (VST)

The ventral spinocerebellar tract, or VST, is another key pathway discussed in the video script. It is responsible for transmitting sensory information from the lower part of the body below L2-L3 to the cerebellum. The script explains its unique crossing over to the contralateral side and its role in proprioception, touch, and pressure sensation.

💡Cuneocerebellar tract

The cuneocerebellar tract is highlighted in the script as a pathway that carries sensory information from the upper limbs and neck to the cerebellum. It is involved in the processing of proprioception, touch, and pressure from these areas. The script specifies that it synapses in the accessory cuneate nucleus before reaching the cerebellum.

💡Spino-olivary tract

The spino-olivary tract is a neural pathway that first synapses in the inferior olivary nucleus before projecting to the cerebellum. It is discussed in the script as an important tract for the transmission of sensory information, particularly proprioceptive signals, to the cerebellum.

💡Proprioception

Proprioception is the sense of the relative position of one's own parts of the body and the strength of effort being employed in movement. It is a key concept in the script, as it is the primary stimulus for the spinocerebellar tracts. The script explains that proprioception is essential for the cerebellum to control posture, balance, and muscle coordination.

💡Muscle spindles

Muscle spindles are sensory receptors located in skeletal muscle that detect changes in muscle length and are involved in proprioception. The script mentions muscle spindles as the source of proprioceptive signals that are transmitted through the spinocerebellar tracts to the cerebellum.

💡Nuclear bag and nuclear chain fibers

Nuclear bag and nuclear chain fibers are components of muscle spindles that respond to different aspects of muscle stretch. The script describes these fibers as playing a specific role in detecting the beginning and progression of muscle stretch, contributing to the proprioceptive signals sent to the cerebellum.

💡Golgi tendon organ

Golgi tendon organs are sensory receptors located at the tendons that detect the tension in the muscles. The script briefly mentions these organs as part of the proprioceptive system, providing feedback on muscle tension to the central nervous system.

💡Inferior cerebellar peduncles

The inferior cerebellar peduncles are a bundle of nerve fibers that connect the cerebellum to the brainstem. In the script, they are described as the pathway through which the spinocerebellar tracts transmit information to the cerebellar cortex.

💡Climbing fibers and mossy fibers

Climbing fibers and mossy fibers are two types of nerve fibers that enter the cerebellum. The script distinguishes between them based on their origin: climbing fibers come from the inferior olivary nucleus, while mossy fibers come from other spinocerebellar tracts. They play different roles in cerebellar function and processing of sensory information.

Highlights

Introduction to spinocerebellar tracts and their function in conveying proprioceptive information to the cerebellum.

The importance of watching related videos on dorsal column medial meniscal pathway and spinothalamic pathway for context.

Explanation of the three main spinocerebellar tracts: dorsal spinocerebellar tract (DST), ventral spinocerebellar tract (VST), and cuneocerebellar tract.

The role of proprioception in providing the cerebellum with information about body position and movement for coordination and balance.

Description of the muscle spindles and their parts, such as nuclear bag and chain fibers, and their response to muscle stretch.

The function of Golgi tendon organs in responding to tendon stretch and their contribution to proprioception.

The pathway of the dorsal spinocerebellar tract from the dorsal root ganglion through Clark's column to the cerebellum.

The unique crossing over of the ventral spinocerebellar tract at the anterior commissure and its ascent to the cerebellum.

The cuneocerebellar tract's focus on sensations from the upper limbs and head, and its synaptic action in the accessory cuneate nucleus.

The concept of climbing fibers and mossy fibers, and their distinct roles in cerebellar function.

The spinal Oliveri tract's peculiar pathway, including its synapse at the inferior olive nucleus and subsequent crossing to the cerebellum.

The significance of the inferior cerebellar peduncles in connecting the medulla to the cerebellum for various tracts.

The role of the cerebellum in processing proprioceptive information for precise muscle movements and posture control.

The anatomical distinction between the dorsal and ventral spinocerebellar tracts in terms of their location and function.

The video's conclusion summarizing the key points about spinocerebellar tracts and their importance in the nervous system.

Encouragement for viewers to engage with the content through likes, comments, and subscriptions, as well as support through Patreon.

Transcripts

I initiatives in this video we're gonna

talk about the spinocerebellar tracks so

again if you guys haven't already please

go watch the dorsal column medial

meniscal pathway first then after that

go watch the spinothalamic pathway after

that watch the pain modulation video now

the last one we're gonna talk about is

the spinocerebellar tract so let's go

ahead and get started on that

so spinocerebellar tracks they are there

as they say they're going from whatever

receptor which we'll talk about into the

spinal cord up to the cerebellum and

most of pretty much all of them are FC

lateral okay so now what are some of

these spino cerebellar tracts

okay so let's talk about these ones so

the first one we're going to talk about

is going to be what's called the dorsal

spine Oh cerebellar tract we're actually

going to kind of write this down you

might see me write it as D s T dorsal

spinocerebellar tract another one is

going to be called the ventral spinal

tract

and again you might see me be a little

lazy bugger and write that as VST and

we'll talk about one more okay which is

really important and this guy is called

the cue neo cerebellar tract okay

just because I'm lazy I'm gonna put C T

alright so these guys are really

important okay and we're gonna talk

about these in pretty good detail and

talk about their stimulus we'll talk

about their receptors we'll talk about

where they're going to in the spinal

cord and where they ascend to where they

terminate so let's go ahead and start

off with the dorsal spinocerebellar

tract first and we'll also just to throw

this one in there at the end we'll do

one last tract and that is actually

gonna be called the spine o Oliveri

tract well throw this one in there at

the end because it's related to the

cerebellum okay goes to the olives first

the inferior olives and then it goes to

the cerebellum so we'll discuss this one

last okay all right so let's go ahead

and get started on the dorsal

spinocerebellar tract so again we know

that these tracks what is a track it's a

bundle of white matter axons basically

that are moving in the central nervous

system and these are ascending tracks

okay so because they're going from the

spinal cord to the cerebellum now what

is the actual stimulus for these tracks

pretty much all of these tracks to make

it easy on yourself pretty much all of

the spinocerebellar tracks respond to

proprioception okay so pretty much all

of these tracks respond to

proprioception so what is this

proprioception proprioception we've

talked about this in the dorsal column

pathway but proprioception is really

important it's basically the since this

sensation the unmanned this case insists

the cerebellum is the unconscious

awareness of one's position of their

limbs are their trunk

in space so in other words how do I

describe that I know where my arm is

right in space I know where my finger is

I know it's touching my nose I know it's

touching my eyes in another way these

proprioceptors not only are they going

up through the dorsal column right that

tract but some of them are actually

terminating in the cerebellum so now

this information is gonna go to the

cerebellum now the cerebellum is

important right because the cerebellum

controls posture it controls balance it

controls muscle tone and coordination of

muscle movements now how does it do that

though how does it maintain our posture

how does it coordinate these muscle

movements help us to have very precise

muscle movements how well the way it

does that it has to be able to get

incoming sensations from our periphery

it also has to consult with our cerebral

cortex and so by doing that it can allow

for it to really calculate an accurate

movement that's why the cerebellum is so

important that it needs to constantly

beginning information from our

proprioceptive that is the primary

important one but it can receive some

other sensations from Xterra receptors

like touch and pressure receptors but I

want you to remember the main stimulus

is proprioception and where is that

proprioception coming from remember we

have those muscle spindles right so we

have those muscle muscle spindles I

remember the muscle spindles the other

two parts you have the nuclear bag

fibers and nuclear chain fibers right

and the nuclear chain fibers were

responding specifically what they were

responding to the beginning of stretched

nuclear bag was responding to the

progression of stretch then we also had

some other structures here which was the

Golgi tendon organ and these responding

to the stretch of the tendons now I did

say that you can also not only respond

to proprioception but also touch and

pressure

okay so this is important it's not as

significant as the proprioception but it

can have some unconscious sensations

that it can pick up like touch and

pressure so it can pick up information

from like your meissner's corpuscles

okay it can pick it up from the pacinian

corpuscles maybe from the Ruffini

corpuscles

all right so different types of

receptors different types of touch and

pressure receptors

now as this information comes together

so we'll have touch and pressure

receptors will have this proprioception

all this information is gonna go into

the spinal cord so it's coming down to

the bottom part of the spinal cord okay

now from here what do you have here you

have the dorsal root ganglion right so

you have the dorsal root ganglion here

this is where the first-order neuron is

so again dorsal root ganglion is where

the first-order in a run of this pathway

it's the dorsal spinocerebellar tract

from here the peripheral process is

picking up the proprioception the touch

and the pressure transmitting it down to

the pseudo unipolar neuron and into the

central process where does it go from

here now there's a specific nucleus that

this is going to stop on I guess very

specific one so this is again we're

talking about the dorsal spinocerebellar

tract so this right here that nucleus is

a very specific nucleus okay and we're

going to talk about that now because we

have to understand this first okay so

let's let's let me explain how this

works this dorsal spinocerebellar tract

because it's important so imagine here I

take a part of the spinal cord here

right and let's say that this is like

the midline region okay and then this is

right side this is left side there's a

set of nuclei located that within the

actual posterior gray horn a certain

length of segments in the spinal cord so

you're gonna find these nuclei okay

they're actually located within the rex

lamina seven if you want to know

and these nuclei extend from c8 all the

way to l2 maybe even l3 so because of

that these nucleus they make a column if

you will all right so what is this

column

they call this Clark's column and it

extends from c8 all the way down to

about l3 and that is that second order

neuron for the dorsal spinocerebellar

tract so that's really important so what

is this nucleus right there that nucleus

is Clark's nucleus it's a part of

Clark's column where does it go from

here okay so now from here from this

Clark's nucleus which is extending from

c8 all the way down to l2 l3 it's going

to come over here into the lateral white

column so over here all this area right

here is lateral white column it's going

to go more than the posterior or dorsal

part of the actual lateral white column

and then guess what it's going to ascend

so now we're gonna have this soccer

moving upwards here so now we should

understand here how this works first

order neuron is within the dorsal root

ganglion second order neuron extends

from c8 to l2 l3 and that is going to be

Clark's nucleus which is actually going

to be here within lamina Rex lamina if

you will Rex lamina seven and then again

from here it's got it's actually gonna

move if see lateral within the posterior

or dorsal part of a lateral white column

and then ascend upwards now from here

where is it gonna go you know there's a

special type of white matter fiber right

here and this is medulla pons midbrain

cerebellum what happens is there's an

actual white matter structure here where

these fibers can actually pass through

and then go and supply thee

cerebral cortex I'm sorry not cerebral

cortex cerebellar cortex this structure

right here that it's actually moving

through is called the inferior

cerebellar peduncles okay

so again what is this tract right here

called this tract is called the dorsal

spine Oh cerebellar tract okay so our

DST we're calling it here all right we

got that sucker down okay now I'm gonna

bring him a little bit more posterior

since we said he was posterior so that's

a little better I like that now

all right cool so we got the dorsal

spine a cerebellar tract which again

that's extending from c3 I'm sorry c8

all the way down to l3 and what type of

sensations is it picking up touch

pressure proprioception sweet deal the

third-order neuron is gonna be the

cerebellar cortex so again you'll have

some nuclei out here that it can

actually go to and again that is going

to be the cerebellar cortex that's its

final termination site okay so we

covered the dorsal spinocerebellar tract

well now we need to do the next one

which is the ventral spinocerebellar

tract this one's kind of a tricky one so

this one's picking up information from

below l3 so any structures that are

coming from below l3 so from l3 l2 l3

all the way down to the coccygeal to the

coccygeal one right all this part down

here is going to be carried by the

ventral spinocerebellar tract so again

from l2 l3 below is gonna be carried by

the ventral spinal

cerebellar tract okay so let's go ahead

and zoom in on that one now so since

this one's a tricky one I want to show

you guys this one it's very interesting

let me actually get this out of the way

here let me put this right here

this is our dorsal spinocerebellar tract

okay this one's very cool I like this

one a lot let's say we come from here

same thing it's also going to be

carrying information of proprioception

it's going to be carrying touch and

pressure but it's going to be carrying

it from information below l2 l3 this guy

again he'll go to what's called the

dorsal root ganglion right in the dorsal

root ganglion you're gonna have this

pseudo unipolar neuron that is going to

be the first order neuron from here he's

gonna come into the actual dorsal gray

horn and sign apps on cell bodies within

the dorsal great horn from here here's

where it gets tricky he crosses over to

the opposite side to the contralateral

side and then ascends upward so what do

we have here for the ventral

spinocerebellar tract so again this one

right here is the ventral

spinocerebellar tract first order neuron

is actually gonna be the doors in the

dorsal root ganglion second order neuron

is gonna be within the posterior or

dorsal gray horn then it crosses to so

it goes across the midline via the

anterior commissure and crosses over to

the contralateral side of the spinal

cord and ascends upward now as it goes

upwards it goes all the way up here so

now there's tract it goes in to where

the midbrain enters and goes through

this white matter structure now what is

this sucker called well what's up this

was the inferior cerebellar peduncles

connecting the medulla to the cerebellum

this is the middle cerebellar peduncles

connecting the pons to the cerebellum so

this one's got to be the superior so

this one right here is called the

superior cerebellar peduncles

okay now from this here's why I told you

it's a tricky tract right look what it

does this guy's really sneaky he moves

behind so you know there's the -

cerebellum right this guy moves from one

side of the cerebellum so let's say that

this in this case this is the left

cerebellum this is the right cerebellum

he moves behind this structure into the

opposite side so look here I'll draw

like kind of like a dashed line here

it's going behind and it's going to the

other cerebellum so across is twice and

then from here it's I naps is on me

third order neurons of the cerebellar

cortex right so that's what's really

important so the ventral spinocerebellar

tract the only difference is from the

dorsal because if they both carry

proprioception touch and some pressure

the only difference is that the dorsal

comes in crosses over if see lateral to

the latter like hollom and ascends

upward all right and then it goes to the

inferior cerebellar peduncles

click with the actual cerebellum the

ventral is actually gonna come in cross

a sin go in and cross again now why did

I say now if you look here let's pretend

for a second I have this guy come right

here so I just want you to understand

why they say that this is dorsal the the

pink pathway here comes in sign APS's

and then look where it goes it goes here

and comes up okay so this is going to be

the posterior part of the lateral white

column this is the anterior part of the

latter white column or and to say it a

different way this is the dorsal part of

the lateral white column this is the

ventral part of the lateral a column so

that's why they call this tract going

upwards the blue tract the ventral

spinocerebellar tract that's why they

call this pink one because it's a more

dorsal to it that's why they call it the

dorsal spinocerebellar tract okay so I

just want to make sure that we're clear

on that okay sweet deal so we've done

the ventral spinocerebellar tract we've

done the dorsal spinocerebellar tract

now it's time to do the kunio cerebellar

tract what's so easy since we set this

establishment down for the dorsal

spinocerebellar that from c8 to l2 l3

is the DS dia the dorsal spine Oh

cerebellar tracked below l2 l3 is the

ventral spinocerebellar tract what you

think is above the cuny a cerebellar

tract so now it's not so hard to

understand that anything above c8 up to

c1 should now be the cue neo cerebellar

tract so this is mainly picking up

proprioception touch and pressure from

the upper limbs and the actual head and

neck structures so that should make

sense so now how does that work okay

let's actually show this guy now let's

do that here we'll come at this level

actually no will come up yeah will come

up at this level so here we're gonna

have this guy coming in here actually

there's more room here let's do it here

so here is going to be this guy right

again this is going to be the peripheral

process it's gonna be picking up touch

pressure proprioception from like the

head the neck the upper limb structures

and then what it's going to send it to

central processing from here when it

goes into the central process it goes

into the post here gray horn right goes

into the post chair gray horn and then

it actually moves upwards apes see

laterally right so it moves upwards and

as it moves upwards it comes to a

special nucleus okay comes to a special

nucleus here that is actually located

within the medulla this nucleus is

really interesting because it's gonna

sound familiar it's gonna sound very

very familiar this nucleus is called the

accessory CUNY eight

nucleus you're probably wait a second

I've heard of that before CUNY nucleus

CUNY ATIS well that was for the dorsal

column medially meniscal pathway here's

the thing with the CUNY Oh cerebellar

track they're not sure yet if it

actually moves up with the fasciculus

CUNY Attis or not but they know that it

actually ascends and moves if see

laterally and picks up sensations from

anything above c8 the head in the neck

and the upper limbs they just know that

it ascends upwards and it synapse is on

this structure here located within the

medulla called the accessory or the

external CUNY eight nucleus then where

does it go remember here just for

simplicity sake here you had the nucleus

CUNY ADIS nucleus gracilis nucleus

gracilis and then nucleus CUNY anus

right they got synapse is from the

dorsal column and then they crossed over

right and when they crossed over we

called that cross the internal arcuate

fibers all right they call that cross at

the internal arcuate fibers well guess

what this accessory CUNY a nucleus gives

off fibers that move through the

inferior cerebellar peduncles they call

these fibers that are coming from the

accessory CUNY a nucleus the external

arcuate fibers so beautiful so this is

called the external arcuate fibers

now from here where will it go it'll go

through the inferior cerebellar

peduncles and it'll go and supply parts

of the cerebellar cortex so again just

remember that does CUNY Oh cerebellar

tract let's actually put this a little

bit more over here they're not sure if

it moves up but they think that it might

move up through the fasciculus CUNY itis

but instead of it actually sign app

saying at the nucleus CUNY Attis it

actually sign apps is at a different

portion here and that is called the

accessory or the external CUNY a nucleus

and then from there fibers will come to

the cerebellum through the inferior

cerebellar peduncles

and these fibers that are going to go

into the inferior cerebellar peduncles

it's called the external arcuate fibers

okay so that covers that guys now last

part I said that we were gonna do a

little tidbit on the spinal Oliveri

tract this one is important too okay

there's special nuclei located within

the medulla and these nuclei here are

called the inferior Oliveri nuclei so

these are called your inferior Oliveri

nuclei okay these guys right here this

system is a little bit odd okay

so another little tricky tract okay how

does this one work okay let's actually

do this one in green once we have this

in green so this tract is a little

interesting so it's going to be picking

up about a bunch of different

proprioception a bunch of different

touch a bunch of different pressure how

does this tract work okay so let's say

here we have this guy coming in again

this is going to be the peripheral

process picking up touch pressure

proprioception and then this is going to

be the central process which is going to

be going into the dorsal root ganglia a

little bit farther here in the dorsal

root ganglia it's going to synapse on a

second order neuron so here's our second

order neuron from here it's going to

cross over it's going to cross over to

the contralateral side through the

answer why

commissure and then move upwards now as

this tract moves upwards it comes in its

sign apses on this nucleus right here

this inferior Oliveri nucleus now from

the inferior Oliveri nucleus something

tricky happens so again what happens

here these fibers are coming in dorsal

root ganglion into the posterior horn

synaptic on the cell bodies they're

crossing to the contralateral side

ascending upwards as the spinal Oliveri

tract as it goes upwards at synapse is

on the inferior Oliveri nucleus from the

inferior Oliveri nucleus these fibers

cross the midline so they cross the

midline and go over to the other side

and then enter into this the actual

cerebellum through what's called the

inferior cerebellar peduncles okay so

the same thing if we were having it come

up here throw on the opposite side what

would it do it would cross over here and

then move into the inferior cerebellar

peduncles and then supply the cerebellar

cortex there's a reason why we should

mention these any fibers that are coming

from the inferior Oliveri nucleus going

into the cerebellum have a specific type

of name these fibers these green fibers

if they're coming from the inferior

Oliveri nucleus they call these climbing

fibers okay they call them climbing

fibers any other fiber any other fiber

which is coming from the ventral

spinocerebellar tract the dorsal

spinocerebellar tract the kunio

cerebellar tract any of that information

that's going into the cerebellum besides

the inferior Oliveri nucleus for example

this pink fiber here this pink fiber was

coming from the dorsal spinocerebellar

tract any fibers other than the climbing

fibers which are coming from the infra

Oliveri nucleus

are referred to as mossy fibers okay

they're called mossy fibers so there's

two different types of fiber fibers

climbing fibers which are coming from

the in fear Oliveri nucleus and mossy

fibers which are coming from anywhere

any other fibers okay

whether it be dorsal spinocerebellar

ventral spinocerebellar or cuneus to

spinocerebellar i'm sorry chunio

cerebellar tract okay and where was the

cue neo cerebellar just so we can have

that here so we can have it all mark

down that was this guy right here so

this guy right here was our cue neo

cerebellar tracked and then the last one

was this green one here and this green

one was the spy no Oliveri tracked all

right knizner so that pretty much covers

everything that you guys would need to

know about the spinocerebellar tracks I

hope it all made sense I really truly do

guys I hope you guys enjoyed it if you

guys did please hit that like button

comment down the comments section please

subscribe you guys also if you guys have

the time please go check out our

Facebook account or Instagram maybe

leave some comments like some pictures

there also if you do have the

opportunity maybe even check our patreon

out if you guys have the opportunity to

donate we truly appreciate it would make

the difference and helping us to make

the most high-quality videos for you

guys as enjoyment

all right ninja tears as always until

next time

[Music]

you

[Music]