all right ninja nerd so in this video we're going to talk about the cerebral cortex primarily focusing on the occipital lobe let's go ahead and get started all right so now let's talk about the occipital lobe so the occipital lobe right we have to understand first off its boundaries what how do we know where the occipital lobe starts and ends so we have a couple different boundaries here one of them one of the boundaries of the occipital lobe is this structure right here this sulcus and what this sulcus does is is it separates the occipital lobe from the parietal lobe right so this is our parietal lobe and this sulcus is called the parietal occipital sulcus what is this called parietal occipital sulcus okay beautiful the other thing that we have to talk about the other boundary here is again that boundary that we said is kind of imaginary so remember we have this sulcus here called the lateral sulcus but there's this little notch here right so there's this little notch this little divot here and this little divot is called the preoccipital notch and if you imagine from this preoccipital notch we draw an imaginary line moving towards the tip of the lateral sulcus that separates the occipital lobe from the corresponding temporal lobe okay and so this sulcus is well there's actually not a specific sulcus it's based on this imaginary line coming from this area here which is called the pre occipital notch all right beautiful now there's two cortex thank goodness only two things that we have to cover within the occipital lobe the first one is this uh green structure we actually want to cover this one first because it's actually an order of the primary and then a corresponding association cortex so this green area here most posterior in the occipital lobe is actually going to be the primary visual cortex so what is it called it's called the primary visual cortex and really the simple function of this is just conscious awareness of visual stimuli right so conscious awareness of visual stimuli that's really honestly it is this involved with conscious awareness of pro of the visual stimuli the other area here is this blue area and this blue area is located just a little bit anterior to the primary visual cortex this is called your visual association cortex so what is this blue one here called this blue one here is called the visual association cortex now what i want you to remember is that the visual association cortex is involved with taking visual stimuli right so taking visual stimuli and basically applying meaning to that visual stimuli okay applying an understanding of that visual stimuli okay and that is important because it basically can take something that we see like a basketball right and that visual stimulus of the basketball will go to the primary visual cortex but then go to the visual association cortex which helps us to do processes of you know looking at the color looking at the shape looking at the different angles of the object looking at basically if it's in motion or if it's not in motion and then helping us to identify or recognize that object so it's also important for recognition of the visual stimuli so meaning understanding and recognition of the visual stimuli all right beautiful so that covers the basic components of the occipital lobe let's dive in a little bit more into the primary visual and visual association cortex all right so the primary visual cortex we're going to kind of talk about how that functions really in the most basic sense right now if you guys haven't already we're not going to go into all the detail of the visual pathway via the optic nerve and then to the lateral geniculate nucleus and stuff if you guys want to know more about the visual pathway of visual fields we have a video on that in our neurology playlist go watch that because it'll talk about this in more detail i want us to primarily focus on the function of this primary visual cortex so let's take let's say you have an object here right so here's our object now this object that we have here is a basketball right now when we look at a basketball a primary visual cortex doesn't necessarily see a basketball it just sees an image right and that image when it hits the retina obviously this image okay will hit the retina and from the retina it'll travel down the optic nerve you know via the optic chiasma it will go to a nucleus in the thalamus called the lateral geniculate nucleus and then eventually it'll move to the occipital lobe now some of the fibers again do cross we're not going to talk about that right now the whole point here is that this object what we see as a basketball again we might not immediately do the primary visual cortex recognize that this object is a basketball all we know is that the visual stimuli from this object is going to be going to your primary visual cortex so then what you'll know is you have conscious awareness okay of this visual stimulus and in this case that we're using for this example it is the basketball right but again we don't know yet that it's the basketball okay what happens is from this primary visual cortex what will it do it'll then take the information about this visual stimulus right now right move to here and then send that information to this cortex just around the same area here what is this here this blue cortex that is our visual association cortex so it'll take the visual stimulus from this object that we don't know as a basketball yet receive it and then go ahead and just act as the highway system to send it to the association cortex what does the association cortex do let's come down and discuss that all right so now what are we going to be talking about here again we talked about the primary visual cortex above and then we started talking about the visual association cortex but now we're going to talk a little bit more in more detail about the visual association cortex and again this is relatively simple this is a very straightforward again we started off with you have an object right that you're visibly seeing okay that object will hit the retina right after it hits the retina moves down the optic nerve via the thalamus lateral geniculate nucleus and then goes first to the primary visual cortex so we have the image of the object in our actual occipital lobe particularly the primary visual cortex then the primary visual cortex will send the information that we have from this object to the visual association cortex then what the visual association cortex will do is it'll look take this object that we have from the uh our visual stimulus and it'll look at what's the color of the object what's the size of the object right what is uh is the object moving right so is there any movement of the object or is the object not moving right and basically when it looks at all of these things and even more kind of analyzing all of this it takes this visual image that we just kind of associate as an object from the primary visual cortex analyzes it in this way right so this is our analysis of it so this is going to be our analysis of that object this is our analysis what it does is another function of this visual association cortex is it has uh it stores recent memory so past memories of what these may be visual experiences that you had in the past of maybe similar objects and so what it does is it compares with past memories okay so past memories and then by doing that what do we do so if we analyze all of these things about the object compare this with past memories maybe we've seen this object before then what does it do by the comp the components of both of these this leads to recognition recognition of the object right recognition of the object that is the function of the visual association cortex why is all of this important well the reason why is if you develop a lesion right in the visual association cortex right you may be able to what let's follow this pathway your vision right from basically the retina is okay the optic nerve is okay maybe going via the thalamus and the large niculate nucleus is okay the primary visual cortex is okay but here at the association cortex is where the damage is so you may be able to see an object right because everything up until this point is fine you may visually see the object but your ability to analyze and recognize that object is now gone because you've damaged the association cortex what is this called when you may have normal vision and see the image but not be able to recognize the image this is called agnosia visual agnosia this is called visual agnosia so again that's why it's important for us to know how this visual association cortex work because if we can't basically analyze and compare the image that we're seeing with past memories we might not be able to recognize what that image is so we may be able to see a basketball but not be able to say oh that's a basketball and that's called visual agnosia okay so it's important to remember that all right nizhny so in this video we talk about the cerebral cortex primarily focusing on the occipital lobe i hope you guys enjoyed this video hope you learned a lot and if you guys did hit that like button comment down in the comment section and please subscribe also down in the description box with links to our facebook or instagram go follow us on that also links down there for our patreon if you guys are willing to donate we would truly appreciate it all right ninja nerds as always love you thank you and until next time [Music] you