What he means is a -10 mV change in the voltage, not that it is a threshold. The threshold is still -55 mV, so the EPSP or IPSP will either excite or inhibit the neuron from firing by bringing it closer or away from doing it, respectively.
The threshold is inversely proportional to the density of VG Na+ channels. It is not constant. The threshold at the dendrite area is relatively higher.
Sir. Please clarify this point.. If every neuron - neuron synapse has inhibitory post synaptic potential. So if an action potential has passed through neuron, it will inhibit now for another action potential? If this phenomenon is for every neuron- neuron synapse ? And for every neuron - muscle synapse there is excitatory post synaptic potential. If its so, whats the benefit of that ? Could you explain please.. Thank you..
Nope. That's not how it works. Think about this only in terms of Synapses (the connection). Imagine yourselves trying to approach a girl. Some friends are pulling you behind (discouraging you because your hair looks bad at that moment) -- Inhibitory impulse. While others are encouraging you (because that jacket you are wearing is cool af) - excitatory impulse. Any Single connection could act as a pulling or pushing unit. When finally encouraged enough (given 4 out of 5 friends are pushing you for action), you might gather enough courage and motivation to finally get over your inhibitions (the negative resting state potential that keeps you From taking any action) to go and ask her out. . Considering you. You might primarily be accompanied by Positive features at that moment. (Nice jacket, great cologne, Good speaking skills etc... Maybe a negative Hairstyle. But you can workout around using so many positive (excitatory signals). So you talk to her, and continually fire excitatory signals to make her Excited enough to reach her action potential and she lends her number to you. And also TAKES ACTION to ask her friend to click a picture of you and her together. On the contrary, if you were a Negative guy - who inhibits other girls from taking action (due to bad hair, bad breath, bad conversation skills etc... Every signal inhibitory), you would go, and depolarize the girl and she would be TURNED OFF, and no number for you, sorry! So, what happened was, many Excitatory neurons excited You (a neuron primarily Populated with more number of Inhibitory Neurotransmitter/Post Synaptic Receptor pairs), so you were able to TAKE ACTION. The inhibitory neuron then took Action and signalled the Next Neuron (third layer neuron). But since the primary signal was inhibitory, the Next Neuron was primed to NOT TAKE AN ACTION Forward. (P.S. a neuron or a Neurotransmitter are not primarily Inhibitory/Excitatory. It's the signalling that determines the Interaction. For e.g You wearing specs with a nerdy look might be a Turn On for one woman while vice versa for other. --( although we all know the popular opinion :p). Similarly a Neurotransmitter like Dopamine might act to excite a Neuron with DA1 receptors, while Inhibiting a Neuron/Synapse with a DA2 receptor. (DA=Dope Amine))
@@tsaed.9170 I can see how an EPSP increases the firing in excitatory neurons. But if EPSPs increase the firing chance in inhibitory neurons (like excitatory neurons by exceeding a threshold), then a (negative) inhibitory action potential is released to the axon (when the membrane potential surpasses -10mV). So for the same depolarization of membrane potential (4cawmi2va33i3w6dek1d7y1m-wpengine.netdna-ssl.com/wp-content/uploads/2018/12/3.1_Understanding-your-brain.jpg), the inhibitory neurotransmitters in inhibitory neurons carry a negative pulse while the excitatory neurotransmitters carry a positive pulse?
Not exactly. It's the action that Neurotransmitter causes. For example, some (many) neurotransmitters create both:- Inhibitory effects in some cases, while excitatory effects in other. Thus, what is more important is the type of Receptor for the corresponding neurotransmitter released. . So, to be precise, it is the excitatory or inhibitory effect of a Neurotransmitter that is finally going to cause the change. (So, a Neurotransmitter that only causes inhibitory effect will always bring the membrane potential down in all Synapses. While a Neurotransmitter like Dopamine or Serotonin will Excite the PSN(post synaptic neuron) in some places (where Dopamine/Serotonin receptors are excitatory) while Inhibiting PSN in the other places (in synapses with inhibitory DA/HT2A Receptors .)
Because here it was starting of entry of neuro transmitter in membrane so before action potential formed here at neuron outer na ions are equal to inner cl ions so negetive so becomes equal so it was 0
MURDR63 the receptor would somehow trigger sodium channels to open, which depolarizes the membrane potential of the neuron, crossing the threshold to trigger the first action potential. You somehow have to take a stimulus and make it open ion channels which will start the first action potential.
Well, actually the threshold is not necessarily -55 mV or - 10 mV. It depends on many factors. I will make a video on it and explain this in more detail for you. Thank you for your comment.
Love the way he says poooostsynaptic potential ☺Great vids as always!
Great video, I have a test over neuron function in 20 minutes and you saved my life here.
big thank you from Texas USA!
The best🎉
I must say this more than sufficient .... the way you explain
Big hug brother love from india ❤️
Thank you very much Dr Umar Azizov.
Threshold is -10V? I remember it was about -55V if i'm not mistaken..
What he means is a -10 mV change in the voltage, not that it is a threshold. The threshold is still -55 mV, so the EPSP or IPSP will either excite or inhibit the neuron from firing by bringing it closer or away from doing it, respectively.
It is, you are correct.
10 Mv is threshold stimulus
Clearly typed before watching 1 minute onward
The threshold is inversely proportional to the density of VG Na+ channels. It is not constant. The threshold at the dendrite area is relatively higher.
Wonderful explanation, thanks for the vedio lecture.🙏
Excellent explanation and beautiful diagrams. Thank you very much!!
A very well organized and well presented tutorial. Keep up the good work!
Thank you, great video!!!
Thanks... I finally understand it! :)
Да благословит вас Бог, доктор Умар, вы потрясающий врач.
🇹🇯❤️🤍💚🙏🙏🙏
you are the best!
omg, beautiful handwriting and diagrams
I love how this is on my exam but my professor never talked about it!
thank you for your work!
Synapse
😍 Thank-you
I understand all things involved in Polarization & Depolarization how take place in Neuron...
Excellent!
thank you verry much its so clear and easy!
1:53 isn’t the threshold at -ve 55 mv? ( just a doubt that’s what I saw in my text book grade 11th)
Thank you for this! I need the visuals to be able to retain all this and my textbook is not helping. This really put it all together for me visually
Thanks for the help. keep uploading more videos. new subscriber ❤️❤️
Awesome lecture ... with integrated and simplified information.
Understood this concept now.
Thank you very much sir .🙏🏻🙏🏻❤❤
Thank you so much! This video helped a bunch as I am a visual learner and your handwriting/drawings are beautiful!!!!!
Me too
Bro do you have this problem 😅 with visualizing nothing you’ll understand 😂
Thank you. Your video was really useful!
An awesome lecture... Thank you:)
I love his accent🤩
Nice graphics!
Sir ! Can u provide a lecture of presynaptic facilitation.plz
Youre so helpful!!!!!
great lecture thanks
this helped me so much! very well structured and easy to understand. Thank you !
Thaaaaanks!
Thank you... Sir.
Thank you, your veido is helpful!
Hello Dr , can we say EPSP & Sub-threshold potential are same ?
beautiful
Sir. Please clarify this point.. If every neuron - neuron synapse has inhibitory post synaptic potential. So if an action potential has passed through neuron, it will inhibit now for another action potential? If this phenomenon is for every neuron- neuron synapse ?
And for every neuron - muscle synapse there is excitatory post synaptic potential.
If its so, whats the benefit of that ? Could you explain please.. Thank you..
Legend
thank you dr
THANK YOU
It was so useful thank you so much saved my life ♥️♥️♥️♥️
Saved my life 😅😅😅😅
Gracias, buen video
doctor. how is the electrical signal of nerve fibers at the extreme point of the polarization reflection
Will an IPSP increase the likelihood of firing on a postsynaptic inhibitory neuron? Thanks!
Nope. That's not how it works.
Think about this only in terms of Synapses (the connection).
Imagine yourselves trying to approach a girl.
Some friends are pulling you behind (discouraging you because your hair looks bad at that moment) -- Inhibitory impulse.
While others are encouraging you (because that jacket you are wearing is cool af) - excitatory impulse.
Any Single connection could act as a pulling or pushing unit.
When finally encouraged enough (given 4 out of 5 friends are pushing you for action), you might gather enough courage and motivation to finally get over your inhibitions (the negative resting state potential that keeps you From taking any action) to go and ask her out.
.
Considering you. You might primarily be accompanied by Positive features at that moment. (Nice jacket, great cologne, Good speaking skills etc... Maybe a negative Hairstyle. But you can workout around using so many positive (excitatory signals).
So you talk to her, and continually fire excitatory signals to make her Excited enough to reach her action potential and she lends her number to you. And also TAKES ACTION to ask her friend to click a picture of you and her together.
On the contrary, if you were a Negative guy - who inhibits other girls from taking action (due to bad hair, bad breath, bad conversation skills etc... Every signal inhibitory), you would go, and depolarize the girl and she would be TURNED OFF, and no number for you, sorry!
So, what happened was, many Excitatory neurons excited You (a neuron primarily Populated with more number of Inhibitory Neurotransmitter/Post Synaptic Receptor pairs), so you were able to TAKE ACTION. The inhibitory neuron then took Action and signalled the Next Neuron (third layer neuron). But since the primary signal was inhibitory, the Next Neuron was primed to NOT TAKE AN ACTION Forward.
(P.S. a neuron or a Neurotransmitter are not primarily Inhibitory/Excitatory. It's the signalling that determines the Interaction. For e.g You wearing specs with a nerdy look might be a Turn On for one woman while vice versa for other. --( although we all know the popular opinion :p). Similarly a Neurotransmitter like Dopamine might act to excite a Neuron with DA1 receptors, while Inhibiting a Neuron/Synapse with a DA2 receptor. (DA=Dope Amine))
@@tsaed.9170 many thanks for the explanation and comprehensive examples :)
@@tsaed.9170 I can see how an EPSP increases the firing in excitatory neurons. But if EPSPs increase the firing chance in inhibitory neurons (like excitatory neurons by exceeding a threshold), then a (negative) inhibitory action potential is released to the axon (when the membrane potential surpasses -10mV). So for the same depolarization of membrane potential (4cawmi2va33i3w6dek1d7y1m-wpengine.netdna-ssl.com/wp-content/uploads/2018/12/3.1_Understanding-your-brain.jpg), the inhibitory neurotransmitters in inhibitory neurons carry a negative pulse while the excitatory neurotransmitters carry a positive pulse?
@@tsaed.9170the greatest explanation I HV ever received 🙏
isn't the threshold -55mV?
Thnks🙂
Thanks ....👏
so is it the type of neurotransmitter released, that determines if whole thing goes inhibitory/excitatory?
Yes
Not exactly. It's the action that Neurotransmitter causes.
For example, some (many) neurotransmitters create both:- Inhibitory effects in some cases, while excitatory effects in other. Thus, what is more important is the type of Receptor for the corresponding neurotransmitter released.
.
So, to be precise, it is the excitatory or inhibitory effect of a Neurotransmitter that is finally going to cause the change. (So, a Neurotransmitter that only causes inhibitory effect will always bring the membrane potential down in all Synapses. While a Neurotransmitter like Dopamine or Serotonin will Excite the PSN(post synaptic neuron) in some places (where Dopamine/Serotonin receptors are excitatory) while Inhibiting PSN in the other places (in synapses with inhibitory DA/HT2A Receptors .)
Why is equilibrium potential of EPSP near zero mv??
Because here it was starting of entry of neuro transmitter in membrane so before action potential formed here at neuron outer na ions are equal to inner cl ions so negetive so becomes equal so it was 0
Isn't the equilibrium potential of Cl -70 mV? And not -90mV. Sorry, I'm just a little bit confused.
it depends on which muscle you're taking about. -70 is for nerve. and -90 is skeletal if not mistaken
Awesome
why Sodium is greater than potassium?
FINALLY
Now, what causes the initial action potential that starts this whole cycle? There has to be a FIRST action potential, the one that propagates.
Could be a receptor, for example a receptor in skin that is triggered by mechanical forces like touch and stretching.
@@darkninja___ And how would that create the initial action potential in this example?
MURDR63 the receptor would somehow trigger sodium channels to open, which depolarizes the membrane potential of the neuron, crossing the threshold to trigger the first action potential. You somehow have to take a stimulus and make it open ion channels which will start the first action potential.
@@MURDR63 th-cam.com/video/SkcflosQn9k/w-d-xo.html Here you can find everything you need
The threshold for an action potential in neurons is -55mV and not -10mV !!!!
I'm studying for a neuroscience exam and this helped a lot. Thanks !
11:47
Good overview but so many incorrect facts such as the threshold for an action potential in neurons; it's -55mV and not -10mV etc.
Well, actually the threshold is not necessarily -55 mV or - 10 mV. It depends on many factors. I will make a video on it and explain this in more detail for you. Thank you for your comment.
I would be grateful if you write other incorrect facts that you are talking about so I will correct them. Thank you!
Tht was clean explanation, thank you sir
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