www.interactive-biology.com - In this episode, I go into detail about how On Center, Off surround Ganglion cells respond to light that stimulates rods and cones in the center and the surround of the ganglion cell's receptive fields.
Pretty disappointing to see a video reaching wrong information to students and not doing anything about fixing their diagrams even after all these comments!
@tashapi01 Yes, it can be confusing. The fact is that the Nervous System is VERY complex. That's just a different type of ganglion cell that responds in the exact opposite way of the On Center, Of surround cells. In response to light in the center, there's the inhibition and post-inhibitory rebound. In response to light in the surround, it gives a burst of nerve impulses. The brain then combines all the different combination and forms the image you see. Hope that helps!
@XxXxSteffXxXx That's a very good question. I'm guessing that it would depend on how strongly each is stimulated. Although, I haven't looked specifically at that so I can't tell you for certain.
In Animal Physiology now and I was so lost. This doesn't go into as much detail as our textbook (probably because you made this years ago) but it's a start! Thank you! :)
@Blue2013KITE It means that when it's stimulated in the center, it gets the OFF response (hyperpolarization and then post inhibitory rebound). When it's stimulated in the surround, it gets the On response (depolarization and burst of nerve impulses). It's the exact opposite of what is shown in the video. Hope that helps.
@molekularacNS I'm not 100% sure about that because I'm not sure what the neurotransmitter is that is released. Might have to look into that. Glad you are watching so many of the videos. Many more are coming :)
Awesome video! It's just what I needed, and it clearly lines up with what is stated in my Costanzo BRS Physiology book, 3rd edition. Thanks for the visual explanation! :D
@molekularacNS The horizontal cells basically inhibit the ganglion cells when they are stimulated. They do this by using an inhibitory neurotransmitter. That neurotransmitter binds to receptors on the ganglion cells that causes the ganglion cells to become hyperpolarized.
Can you explain what happens in the fovea where each ganglion cell is mostly connected to only one cone. Do those ganglion cells not have center and surround at the sime time? Are their just center OR surround organized? I don't quite understand that nor I can find the info anywhere.
Neuroscience-exploring the brain by Connors and Paradiso shows that the order is: For the center: Rod - bipolar - Ganglion For the surround: Rod - horizontal cell - bipolar - Ganglion
Hey! I really like your videos and they are really helpful for studying, but i have to say that there are sometimes mistakes in them. In this video you say, that the ganglion cell and the bipolar cells of the surround-area of the RGCs periphery field are connected via horizontal cells. Actually it's the Amacrine cells that form that connection, horizontal cells connect neighbouring photoreceptor cells. But that leads to the same center-surround effect you are describing, caused by lateral inhibition, it is only the image which is not correct
@InteractiveBiology I've heard that horizontal cells inhibit glutamate release from neighboring photoreceptors as well. Which book did you use as your source?
how I can I describe the different ganglia cells in different parts of the visual processing? I know they are at the eye level and in the cortex level. Can you please describe its function and importance please?
Thank you!! My psych text sucks and takes all the detail away for understanding the mechanism. You filled all the voids with your video!! THANNNNNNNK YOOOOOOOOOOOU!!!!
I applaud your efforts to explain this fascinating topic, but as has been pointed out more concisely by others, this is unfortunately a little confused (and wrong), Horizontal cells perform lateral inhibition in the outer synaptic layer - i.e. they are post-synaptic and pre-synaptic to rods (in your example) and pre-synaptic to the relevant bipolar cells (as well as being connected to each other via gap junctions). If anything, the position at which you show horizontal cells to be in your video (within the inner synaptic layer) should actually be taken by Amacrine cells. But the extent to which Amacrine cells are involved in feedback mechanisms is not (as far as I have learned to date) fully understood. I believe that there is very current research into whether starburst Amacrine cells might be involved in retinal processing for motion detection. I can see how the key idea of general lateral inhibition can still be drawn out as you present it, but the relative positions of horizontal and amacrine cells is crucially important.
Hi, i was initially confused with the topic of lateral inhibition and hoping this video would help. Should the photoreceptors then lead to horizontal cells, then leading to bipolar cells then connecting to amacrine cells which feed into the ganglion cell? Also, what is lateral inhibition and what is it caused by? i dont understand the inhibitory process. thankyou :)
@PittDr All questions are answered in the Interactive Biology community forums from now on. Go to the website in the description and then visit the community. This is to make it as efficient as possible as we have multiple people over there to help answer questions. All the best
So horizontal cells connect adjacent rods and cones? So does this mean if surround is off the horizontal cells give an inhibitory effect to the central on rods/cones? Please someone just explain the horizontal cells action in the more generally accepted textbooks.
Question: So this is the direct cause for the slightly over contrasted boarder we see between two different colours (or brightnesses/energy potentials, meaning something in contrast to each other), right?awesome videos your creating by the way :D
What is the point of inhibition in the surround? What does that tell the brain?? Is this the same for cones?? I thought cones were generaly one photoreceptor cell to one bipolar to one ganglion cell, so do they have receptor fields and if so how do they work? Basicaly my major problem with understanding this is that I don't know why this is the mechanism, why can't the brain just use an on stimulus when a photoreceptor is stimulated by a photon and an off when it isnt and make up the picture?
You are very much welcome @JS. Glad you got value from it. Make sure to subscribe to the channel, because I have a lot more content like this coming to help you understand how the human body works 👍🏽.
@jock10171017 The truth is that it's even more complicated than you describe. There are always details that can be left out. The human body is much more complicated than what I'm showing in this video and what you are saying in your comment, and more complicated than we fully understand it to be. This video is a general overview, and does illustrate some of the major processes that happen.
This video kind of misses a bit of the information flow... Mohammed seems to have summed it up more accurately - Receptors -> Horizontal (with feedback inhibition of receptor output) -> Bipolar -> Amacrine (with feedback inhibition of bipolar output) -> Ganglion
@aykhk7 I don't remember the textbook. It's from notes I took in college. If your book says something different, go with it. My videos (like many textbooks), can have errors in it. Do your research and you'll find the answer :)
I watched my lecturer's response like 100 times, didn't understand anything and left even more confused. I watch this video once, and I understand it so much better. Bless you
AMAZING. I've been sitting here, trying to figure out this concept and it just hasn't been working. Great video!! You might just help me save my grade in neuro :)
@virregribbe Sorry to break it to you, but it's so complex that I've seen different descriptions in different books, so I picked one. Yeah, I know - It's crazy. We don't fully understand all aspects of this complex thing we call the human body. Makes you wonder . . .
Horizontal Cells synapse with photoreceptors in the External Plexiform Membrane. So Ph--H--Ph. Amacrine synapses with Ganglion Cells in the Internal Plexiform Membrane. so it's G--A--G.
Yeah, this was confusing for me as well in Neuro. My only question is, what's the point of off center/on center cells. Our prof spent alot of time on this and I just want to know the bigger picture.
The Pathway is Photoreceptor - Bipolar Cell - Ganglion Cell. The different effects of ON-center or OFF-center bipolar cells or ganglion cells is due to the receptors expressed on the bipolar cells. Horizontal cells (and amacrine cells to some extent) are involved in LATERAL INHIBITION. This process is used by the retina cells in order to accentuate contrast, i e, borders of between light and dark objects in or visual field. I guess it's why we can see a white paper on a white table with ease.
The center of a receptive field of a ganglion cell. Remember that the receptive field is composed by many photoreceptors in retina. Thus, the center is the photorreceptors localized in the center of these fields.
And you are right, text books do have mistakes at times, but in this case i haven't seen a difference with most of the major text. All the same what determines knowing the actual orientation of the cells is histology and electron M. So we must research.
@thesameidiot All questions are answered in the Interactive Biology community forums from now on. Go to the website in the description and then visit the community. This is to make it as efficient as possible as we have multiple people over there to help answer questions. All the best
