Neuroanatomy, decussations, commissures, spinal tracts, upper & lower motor neurones

Strap yourselves in, this one's a bit of a monster. It's not always best to chop up anatomy into small chunks because it helps to link bits together, to make sense of it all. I'm going to talk about decussations within the nervous system, that is, nerve fibres crossing over from one side of the body to the other.
We'll talk about:
- decussations and commissures
- spinothalamic tracts, dorsal columns (sensory)
- corticospinal tracts (motor)
- upper motor neurones vs lower motor neurones
- the weird things that can happen when only half of the spinal cord is injured
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[@studyorrelaxationmusic7496]

You have turned anatomy into something very interesting for a person who used to procrastinate hearing the word Anatomy... thank u very much sir. I am watching your videos back to back without even getting slightly bored.

[@oganesson7034]

I can't thank you enough for actually making this video. You have turned something so complex into something so simple/straight forward and with freaking pipe cleaners!!! You sir are a genius and an outstanding teacher. Hopefully we can see more neuoranatomy videos ,especially one on cranial nerve decussations in the future. Cheers!

[@SamWebster]

Really? It worked? That's great! I'm going to need a lie down after this one before I tackle another neuroanatomy topic!

[@oganesson7034]

Haha I feel your pain

[@futurephysio6375]

If there was ever a video I needed two weeks ago......

[@margaritaasparuhova5292]

Fist time I watch the videos - I got fascinated and excited about the topic and by the way you teach. Second time I put my efforts into learning - writing, drawing, talking about it with my loved ones - and I am really learning - all thanks to your great teaching. Thank you so SO much....

[@caitlinmoore8740]

I wish I'd found this channel before, I've never picked anatomy up so fast! Great teacher

[@ianliwag7311]

Amazing instructor and very honest educator. Thank you so much, Sam.

[@angelainglismusic]

Boy oh boy, are you fabulous. Thank you so much. You're a pleasure to watch and listen to. So much better than text books.

[@phubusa2022]

Your lectures are so interesting!!! The way you make use of the visual aids have improved my understanding of the discussions!!!

[@agie3096]

You make it way easier for me to understand Doc. Thank you. I like how honest you are too when you said that it's a bit challenging to learn NeuroAnatomy even though you are the best at teaching.

[@jessicamarchiori3516]

I can't thank you enough, for 3 years I've been trying to learn this. My final exam is on Wednesday and I have finally been able to get in a way I can explain it. you are an absolute lifesaver. you are a natural teacher. Great visuals. xoxoxoxox

[@asimasim8207]

Brilliantly explained. Well done Sam

[@wandaterry2278]

I really find it interesting the discussions that this has brought about which is more learning. Love it!!!

[@jentomholbarrett9129]

Thank you, it looked really painful talking about it, but you made it really easy to understand. thank you so much.

[@harikachawhan3999]

love from India Sam..u are a life saver.. thanks buddy

[@chinmayeechavan5724]

This is sooo good ! . Studying neuroanat is not tiresome anymore !

[@mohammadadnan2844]

YOU'RE A DAMN GENIUS!! For this 'experiment'

[@heyitsme5831]

How did I not know about your channel during my struggling first year days 😭😭

[@golffitnessireland7730]

I just love sit sit down on Saturday evening after work put feet up and watch your videos! Such interesting and great entertainment!

[@nicolebonet6119]

These videos are brilliant. Thank you!!!

[@suefowler6016]

Thanks for tackling that. From my point of view it was definitely worth doing. Thanks again.

[@bernardwandera36]

watching this from Kenya, I love your work.

[@DaleStephens1949]

Thank you for your inspirational presentation.

[@arturoplaying]

You are amazing, love your way of teaching

[@ellesonia_]

thank you so much prof, i have been struggling with neuroanatomy and hearing you say it’s hard even for you makes me feel a lot better❤️

[@wenonadancy1927]

Just found your videos - perfect timing before exams!! Thank you!!

[@priyankarane6554]

Initially i was struggling to do this topic But now it's really simple ❤❤❤❤❤❤❤❤❤❤ Thank you so much..

[@drdoody69]

Dear Sam, you've been extremely thorough and presenting stuff that can be iffy and too solid for any fun in a very unique & exciting way. This is in almost all (if not all) your teaching video posts - I haven't seen them in total. Please allow me to mention the following that might be additive for more clarity, if not mistaken: - The spinothalamic tract (ascending) is subdivided into: 1) Lateral spinothalamic tract - the main one and for pain & temperature. It decussate "Two Segments" above entry. 2) Anterior spinothalamic tract - for crude touch & pressure. It decussate similar to above. - The dorsal & ventral spinocerebellar tract (ascending) - the ventral doesn't decussate, while the dorsal decussate twice. Thus lesions are always "ipsilateral". It's for unconscious proprioception. This one is a bit confusing but clinically important. - The corticospinal tract (descending) is also subdivided into: 1) Lateral corticospinal tract (pyramidal tract at medulla) - decussate at inferior part of medulla, and for muscles of the limbs. 2) Anterior corticospinal tract - decussate at segmental levels, and for muscles of the trunk. - The rubrospinal (from red nucleus) tracts (descending) - decussate early in its pathway, and for flexors & extensors muscles. - The reticulospinal (from reticular system) tracts (descending) - doesn't decussate, and only for supplementing and facilitating the corticospinal tract(s). This is a key point in some aspects of rehabilitation recovery in very simple terms. Human body is amazingly formed and created! We will keep forever discovering & confirming this fact. Happy for your feedback!

[@wandaterry2278]

I can follow you and that is so amazing for me at almost 74. I love to learn. Thank you.

[@gulcinkahraman686]

this was so helpful you are really saving me

[@hyderahmad9386]

Sir u r really nice this is the real art of teachng thanku so much

[@fatimaemad7402]

This is the best video about soensory and motor tracts thank you ☺️

[@vildanak2489]

thank you, this video is really helpful!

[@graciaissa685]

You are amazing Sam🙏🙏. Thank you

[@gunasegaranmurugiah1326]

Tq so much. I been struggling with the neuroscience. Tq so muchhhhhh!

[@cpowersmith]

thanks for the amazing content what a great teacher!

[@michaelmakarchuk8662]

Spent honestly 4hrs+ trying to understand this topic using a variety of sources. This video was finally the one that made it 'click' for me - thank you!

[@natashachihanga108]

Me too!!

[@duocphamtruongtho4462]

Its very helpful! Thanks!

[@hafizzeeshanwahab9917]

Good explanation thanks sir...

[@rohitbhaskar]

Thankyou Sir, You are making medicos life easier 😍

[@mannpatidar8764]

U are just awesome sir ur way of presentation and explaination is so simple and easy to grasp and learn... Thanku for making learning feel so easy.. 🙂🙂🙂🙂🙂just expect ing more anat videos.

[@ZahidKhan-le6tb]

Well done ...I m so thankful to your this video..it make my life easy....🤝🤝👏👏👏👏👏👏

[@josephphiri8893]

100 % Thank you very much! My lecture

[@haleemahabdulaziz8410]

You're amazing ❤❤

[@paulmaina8333]

Thank you very much

[@anut32]

Very very good

[@bublisoniyak6227]

Thank you so much sir!!!!❤️❤️❤️

[@agie3096]

Would you be able to explain UMN and LMN as well please? Thank you so much. :)

[@ashuhooda1012]

It's really helpful m great full to watch it👍👍Dr Sam

[@Dankkrg]

Great idea for explaining tracts (my neuroanatomy exam is tomorrow, so it definitely helps). Doing an awesome job, keep it up! I think Dr Acland better watch his back cuz a Brit just made Anatomy easier than he did😊

[@SamWebster]

+Daniel E Thanks! Good luck. Believe it or not, Dr Acland was also originally from Britain. I have a lot of respect for him. My videos are quick and dirty compared with his lovely fresh dissection videos.

[@xmega456]

omg youre a master, im from perú and i never had a class of neuroanatomy like that, i really wish a master like you in my country but with speak spanish haha sorry my english is bad.. whatever... thank you so much ! youre a genius

[@SamWebster]

Cheers.

[@muhammadjunaidali9449]

awesome

[@adachukwuokafor1536]

Who else watched till the end because young Sam looked 🔥

[@alexanderkenniethbam]

What is the purpose of decussation? Thank you.

[@marko1114]

Awesome

[@molitirionMUSE1996]

What would I do without this channel. Fail anatomy probably

[@josephphiri8893]

Really helpful,thank you very much my doc

[@sylshoemaker6734]

Also THANK YOU from Germany!!! 🎉

[@SamWebster]

No problem, cheers, buddy.

[@harynoor8163]

can nerve regenation then self ?

[@Lerch-zc3ww]

I love your videos....and will add from personal experience that neurology may be the 'abysmal science' of the medical world.

[@kadiegalewaler2976]

When ever one neuron meets another does it always cross over? Also is that for every nerve in the body or just the spinal cord.. if that makes sense (probably not) sorry I know it’s hard to explain

[@susanrivard3959]

Please...can you describe what Innovate means? i cannot find a good explanation so far. i really enjoy these videos. Does it mean connect or something else?

[@biomedicalsciencesociety4486]

I think he said innervate, meaning it’s the nerve for tissue xyz

[@pookista]

2022 still bumping it

[@quotesAndCo]

mannnnn hats off

[@bublisoniyak6227]

Sir you looked so different 4 years ago! 😂🤘

[@yash.jaiswal]

I love you🤗

[@priyankarane6554]

Can u go more with neuro??????

[@johnmikhail8059]

Here is a reason why we have decussations and commissures that I thought of. We have these crossing overs so that damage to one side of the brain or spinal cord does not cause a complete loss of motor control and sensation to one side of the body which is likely to 'deal' with the environment. In other words, dividing the loss of sensation and motor control over both sides of the body means less loss of sensation and motor control for one side of the body which is more useful since that side of the body encounters the environment a lot. This could have played a role in the survival of ancient animals and got passed down to other animals and eventually humans.

[@rashmika9742]

John Mikhail that's cool! I think maybe the fibres cross over so that they can be longer. If they were to go straight down and not cross, they would probably be significantly shorter. Just an uneducated guess on my part. :) neuroanatomy is a really cool mystery.

[@IK-fg4gw]

Was this video filmed recently ?

[@SamWebster]

+ibro khan Yes. I just finished editing it today.

[@medicus2876]

Why does decussation occurs ? @samwebster

[@wandaterry2278]

Would you give me the name of the text book?

[@pcchoon]

i love you

[@akshatsharma5536]

❤

[@charlieh2088]

18.32

[@dryoutube]

Ascending tracts: kzbin.info/www/bejne/jYitl2SVZryinZI Spinocerebellar tract for unconscious proprioception, Posterior Column tract for discriminant (fine) touch and conscious proprioception, Spinothalamic tract for crude touch, pressure, temperature and sensation Descending tract: kzbin.info/www/bejne/pnimpaiVoLJ4gKc Corticospinal tract: Anterior and lateral.

[@mid1chosen]

funniest part of the video 0:26

[@LittleGenius399]

That's Earth made easy!

[@bhaveedesai5543]

OG Gregory House

[@yussuf.95]

where's cranial nerves decussation ?😢👀

[@eric6345]

My recommendation is for this video to be re-done. I ultimately had to stop watching because to me it seemed unscripted, unprepared. My personal preference is for video lectures to get right to the point, no nonsense. Thumbs Down