 Hello everyone, how are you? Am I audible? Am I audible dear? Yes sir, you're audible. Yeah. Let's see. What are we discussing in the previous class? What are we discussing in the previous class dear? Please let me know. Sir, I'm not sure. I had connectivity issues last class. Conducts and part is finished. Now we will be talking about the nervous system. Okay. We will be talking about the human nervous system. Some division of that first. Is the screen visible? Is the non-conducting process. Yes. Screen is visible now. Let's see. Let's see what it is. Your nervous system. First see the organization. We'll talk about human nervous system. Let's see. Human nervous system. Human nervous system. What's that? It is divided into two principle parts. Okay. One is the central nervous system. Nervous system. And another is peripheral nervous system. Agreed. One is central nervous system. Another is peripheral nervous system. See. Your central nervous system is going to be going to have brain, spinal. I will see. Say over here. It consists of, let's see. It consists of spinal. Everybody. Everybody. It consists of 12 pairs of cranial nerves. And 31 pairs of spinal nerves. Yes or no? Yes or no? Yes, sir. We'll talk about cranial nerves. What are cranial nerves? Cranial nerves originate from, from which point? Tell me. From brain. Okay. And as far as spinal nerve is concerned, it is going to originate from spinal nerve originate from spinal cord. Agreed. Originate spinal nerve. Peripheral nervous system is again divided into two sections. One is, one is what? One is somatic nervous system. One is somatic nervous system. Another is autonomic nervous system. One is somatic nervous system. Another is autonomic nervous system. Agreed. Yes, sir. Somatic nervous system is going to supply your somatic tissue or skeletal muscles. It supplies the skeletal muscles. Okay. Autonomic nervous system is going to supply. It supplies visceral, done, noiseless, noiseless. Autonomic nervous system is further divided into, autonomic nervous system is further divided into the parasympathetic system, nervous system, and sympathetic nervous. Agreed. Everyone. Yes, sir. Sympathetic nervous system. Usually they, they act antagonistically. Means they, usually they have opposite functions. Can we hear? Excuse me, sir. Yes. Sir, the nodal tissue of the heart doesn't come under either of these systems. Nodal tissue is a muscular tissue. Got it, sir. Nervous tissue at all. They are supplied by these systems. Okay. Nervous system can moderate or mediate the activity of nodal tissue, but nodal tissue is not direct. That is why our heart is myogenic, not neurogenic. Yes or no? Yes. Nervous system do not have direct control on your heart. So, sir, both the sympathetic and parasympathetic moderate the functions of nodal tissue, right? Yes. Sympathetic will increase the heart rate. Parasympathetic will decrease it. Yes, sir. Got it. Done, sir. Everyone, done. We'll talk about brain now. We'll talk about brain now. Let's see. We'll talk about brain now. Let's see. Following, there are following embryological structure. There are following embryological structure that is going to form the brain. One is Progen Cephalon. Just a minute. One is Progen Cephalon. Is it visible, blue color, warrior? Yes, sir. Median Cephalon and Romain Cephalon. Agreed, dear? It is like this. Yes. Progen Cephalon is going to develop into. Progen Cephalon is going to develop into four brain. Median Cephalon is going to develop into mid-brain. Romain Cephalon is going to develop into myelan Cephalon and metan Cephalon. Under myelan Cephalon, metaloblongata is there. And under metan Cephalon, pons and cerebellum is there. Okay. You first write down this thing. Okay. Brain. There are three embryological structures from which brain is going to be formed. One is Progen Cephalon. Then brain, bromine, Cephalon. Agreed, everyone? Done, everyone? Sir, just a minute, sir. Yes, no issue. Done. No issues. Nothing is. See, I will talk about cranial capacity. Cro-magnon main, having a cranial capacity of 1650 CC. And modern men having 1450 CC. What do you think? More cranial capacity means more intelligence. Can you say that? Cro-magnon main is more intelligent than the modern men. Can you say that? Can you say that? It is not there. Actually, cranial capacity is more. What happened in modern men? The brain is thrown into these kind of folds. This is known as sulcus and gyros. This is helping in accommodating more number of neurons. This is helping in accommodating more number of neurons in lesser space. Yes or no? Because of more sulcus and gyros, it helps to accommodate more and more number of neurons. More is the sulcus and gyros. More is the IQ of that person. Can you read here? Yes, sir. Okay. I have cut the brain from the center, from the, you can say, middle, and I am able to see only one half of the brain. This is the left half. Yes or no? You can see this thing. This thing. Can you see this thing? Just give me a minute. I am taking, I am trying to take this file at the original position. Okay. In this app, I am not able to write in a manner I want to write. Just wait. Let's see. Can you see over here now? Can you see over here now? This area, this structure, we all can see this thing now. This is corpus callosum. What? Corpus callosum. Corpus callosum. It connects the two cerebral hemisphere. It connects the two cerebral hemisphere. It is the largest commissar of the brain. What is the meaning of commissar? Commissar means a structure which, which connects one side to another. Agree, dear? Agree? Yes. This is corpus callosum. Okay. This is the interior part of the corpus callosum. Corpus callosum known as genome and the posterior part is known as esplanium. Esplanium. Okay. The anterior part of the corpus callosum is known as genome and the posterior part is known as esplanium. Getting my point. So it is there. Getting my point here. Four brain is divided into two parts. Sorry. One is telencephalon and one is diencephalon. Getting my point. Telencephalon consists of cerebral cortex, corpus stritum, hippocampus and amygdala. And diencephalon consists of epithelmos, thalamus, and hypothalamus. Yes or no? Four brain consists of telencephalon, which is having cerebral cortex, corpus stritum, hippocampus and amygdala. And diencephalon having epithelmos, thalamus, and hypothalamus. Agreed, dear? Tell me. Yes, sir. Yes. Here, mesencephalon. Mesencephalon. Here is the midbrain. I'm going to tell you midbrain in the next diagram. Agreed? So, I am talking about, now you see. Four brain. Four brain mainly consists of cerebrum and diencephalon. Getting my point. Cerebrum consists of two hemispheres, known as cerebral hemispheres. Now, the two cerebral hemispheres are connected to each other with the help of corpus chelosum. That thing I have written over here. It is the tract of nerve fiber. Tract means a pathway. Its anterior part is known as genome, and its posterior part is known as sphenium. Now, is it? All right. Tell me, dear? Yes. Now, several cortex. It is the outer part of the cerebrum. Can you people imagine a watermelon? Have you seen that watermelon? Yes, sir. What is there in the outer part? The whitest portion that we cut and throw. Yes or no? We used to eat reddish part. Yes or no? Yes, sir. Without cutting. If you will see the watermelon from all the side, will you be able to see the red part? Will you be the, will you be people able to see the red part without cutting it? Similar is the case of, similar is the case of what? The brain, sir. Brain. Similar is the case of brain. It is wrapped all around by the cerebral cortex. So, you will see cerebral cortex from all the side. If you have to see the inner structure, you have to remove the cerebral cortex. Yes or no? Yes. You will see the outer, it is the outer part of the cerebrum. Thickness is only 2 to 4 millimeters, consists of six layers of neuron, and around 10 billion pyramidal, spindle, oscillate neurons out there. They are based on the shape only. Nothing special in this. You will see, it is divided into lobes. See, a big sulcus over here, known as central sulcus. What? Central sulcus. Divide it into frontal lobe and parietal lobe. And one sulcus is parietal orcipital. Sulcus means depression not here? Yes, sir. Yes, parietal orcipital. It is going to divide it into, it is present between the parietal lobe and the occipital lobe. Agreed? And here is the lateral sulcus. What? Lateral sulcus. Agreed? Lateral sulcus is going to be present between the frontal, parietal and the temporal lobe. So how many lobes are there? The frontal lobe, the parietal lobe, occipital lobe, and the temporal lobe. Yes or no? Yes or no? Tell me, dear. Yes, sir. Yes. See, this is the central sulcus, if you will see. See, this is the deep central sulcus. No issues? So, there are certain areas that is there in your brain. There are certain areas that is there in the brain. Just in front of the central sulcus, you are going to get the primary motor area. What? Primary motor area. And behind the central sulcus, it is the primary sensory area. Agreed? Primary motor area and primary sensory area. Read? Yes, sir. Yes, sir. What is the, what is the, what is the, you can say, function of primary motor area or your general motor activity, like walking and all. You keep on hearing the, cerebellum is going to have role in, cerebellum in the hind way. It is going to have role in equilibrium or balancing. Is it like that? Yes, sir. What will happen if your primary motor area will be affected? And what will happen if cerebellum is going to be affected? Have you seen a drunk person walking? Yes, sir. Have you seen? Is that person not able to walk or that person is not walking properly? They are not walking properly. Not walking properly, not here? Tell me. But he is able to walk. In that case, what do you think primary motor area is affected or cerebellum is affected? If a person is not, if a person is not able to maintain the balance in that case, you should understand that. You should understand that, that person, persons, sorry, cerebellum is affected. If primary motor area will be affected, analysis will be there. Person will not be able to move the limbs. Yes or no? So have you understand the difference between the role of primary motor area and cerebellum while walking? Yes, sir. Yes. In front of primary motor area is pre-motor area. It is going to help you in motor planning. Motor planning. Agreed? Dear? Yes, sir. Agreed? Agreed? So front and low is going to have primary motor area and pre-motor area. Yes or no? Like you are running and you have to change your, you can say, direction or you have to, you have to change from any present condition. Okay? Planning for that is going to be started in pre-motor area because without planning you are not going to do anything. Yes or no? Yes, sir. Agreed? No issues? No issues? Yes. Let's see dear. Let's see dear. What I wanted to tell you are pre-motor area is over. Now, what is behind the central sulcus? The primary sensory area. You have two kind of senses. One is general sense. One is general sense. Yes or no? Another is a special senses. A special senses is like visual sense and all. Yes or no? Visual sense and all. Agreed? Dear? No issues? No issues? No issues. No issues. Here, so you see, visual is also a sense only. It is there in the occipital area where it is there in the occipital area. Occipital lobe. Yes or no? Occipital lobe. No issues? No issues dear? Yes. No issues? No issues? But general senses like touch, pressure and all pain, that will be analyzed by primary sensory area. Have you understood the role of primary motor area and primary sensory area? One more area that is of a special sense is here you will see here if you will see this is the auditory area. It is responsible for your, it is responsible for your sense of, you can say hearing. Yes or no? Now's are going to take the impulse to this area only and here only it will be analyzed. Here only it will be analyzed. Agreed? Here? Tell me. No issues? No issues? Here is the Broca's area. Broca's area is the motor speech area. All the motor activity of, all the motor activity of your speech is going to be controlled by Broca's area. And one next area is the sensory speech area. Agreed? No issues? Sensory speech area. What you people are speaking, you are going to have sense of that thing also. Yes or no? If I am speaking something that I know what I am speaking. If Broca's area will be affected, in that case what will happen? The motor function of a speech will be lost. And what will happen if Varnik's area is affected? You will not be able to analyze what you are speaking. Yes or no? Understood? Yes. So if Broca's area is affected, you will be able to understand what the other person is speaking. Yes. Actually, see what other person is speaking. That is, for that your ear is responsible. Yes or no? Yes or no? That is the point that, see two things are there. One thing is you are understanding somebody else's speaking. For that ear and auditory area is responsible. Yes or no? No role of Broca's area or Varnik's area is there in that. Yes or no? Yes. It is there like you have to speak, you have to perform motor activity, you have to move your tongue and all. For that Broca's area is there. And what you are speaking that also you can say, you need to understand. You used to understand that thing, what you are speaking. But you do not understand. So for that what is there? Broca's area. Sorry, Varnik's area. Read here. Also, Varnik's area is not responsible for understanding what the other person is speaking. For other person, what other person is speaking for that auditory area? Yes, got it. So just a minute, could we copy the diagram? Yes, you can copy this also. Yes. So the motor areas are for processing whatever we've sensed and sensory areas, they just pick up the stimuli, right? Yes, what are you saying? So the motor area processes the senses that we have got, like the everything, whatever we can sense in the stimulus and the sensory areas, they just pick the stimulus to the brain, right? Stimulus is what? Like anything that is starting from your peripheral organ. Okay, that has to go to brain. Brain will analyze that. Brain will send motor signal according to that one. Okay, so your limbs are moving and all the motor activity will be performed by primary motor area. Okay, the voluntary motor activity, voluntary, that is under control of your will. Sensory area is for, many senses are there, that will be analyzed over there. Read? Yes, sir. So is that structure before the lateral sulcus, also a sulcus or is that an arrow? So the white line before the lateral sulcus between the occipital lobe and the lateral sulcus, is that the sulcus? Yes, that is the sulcus only, yes, depression. Yes, sir, got it. Done everyone? So just a minute, sir, could you repeat the functions of verniks and brokas area again? Verniks area is there for interpret what you speak, or you can say sensory part of your speaking. Okay, and brokas area is there or motor part of your, you can say what you are speaking. Getting my point, like your tongue movement and all are there, that will be controlled by brokas area and verniks area is going to control your sensory speech problem. Okay, like if verniks area will be a factor now, what you are speaking, you are not going to interpret that at all. Yes, sir, got it. Yes, now cerebral cortex having three types of areas. One is primary sensory area, second is primary motor area and third is association area. Primary sensory, primary motor we have discussed to see, you have many senses, like you have sense of hearing, sense of, you can say reason is there, many senses are there. There must be coordination between them, yes or no, there must be coordination between them. What I want to say, say, please see to it, like, like, if you do not have, getting my point, please mind my words, like somebody is scary for your eyes and that is present for your ear, what kind of accent you are going to take, will you be able to take any accent, whether you are going to listen to your eyes or ears, that will be a complicated problem. Yes, sir. So, there is communication between all your senses, whatever eye is thinking that will be communicated to, you can say sense of eye is there, the similar sense should be there for other sensory structures also, okay. So, they are communicated, you guys are connected. So, association area is neither clearly motor nor clearly sensory, its functions are, functions are inter sensory association, memory and communication. Three functions are there, it is important. This thing you people should write down, okay. Several cortex having three types of area, either it is primary sensory area or it is primary motor area or it is association area, yes or no, yes. Done? Done, everyone, Diane Saplone. Can you people imagine your rooms? Rooms are there, no? It is having a roof, it is having walls and it is having floor, yes or no? Yes, sir. Similar structure is there in the brain, that structure is third ventricle, what? This area is third ventricle, it's roof, the GP thalamus, this part is GP thalamus, okay. This part is hypothalamus, this is the floor and all the walls, these walls, lateral walls are what? Thalamus. Agree, dear? Agreed? Tell me. Yes, sir. Lateral wall is thalamus, the upper wall is GP thalamus, okay and the lower wall is hypothalamus, lower part is hypothalamus, yes or no? So, third ventricle is a structure, its roof is GP thalamus, yes or no? Its wall is thalamus and one structure is hypothalamus, agree, dear? One structure is hypothalamus, that is situated in the base of the third ventricle, to which pituitary gland is also connected, agreed or not? Yes, sir. Agreed or not? Everyone? See, epithalamus consists of, epithalamus consists of pineal body, pineal body or gland plus havenula, havenula is a stalk-like structure only, structure only, havenula is a stalk-like structure only, getting my point to which pineal body is connected, okay? Pineal body is endocrine gland, its secret hormone known as melatonin, agree, dear? Thalamus acts as relay center, what? Relay center, how? Try to understand my point. If you are going to, you can say, going for electrical wiring in your room, are you taking wires through the wall or through the, you can say, between the rooms only? From which area you are going today? Through walls, no? Yes. Through walls, no? Similar kind of thing is there, anything that is going up, going up, or coming down, will go through the wall of the third ventricle, that is thalamus only, no? That is thalamus only? Also, could you repeat that? I told anything that is going up to the salivary cortex or coming down, that will go through the wall only, not through the ventricle? Yes, sir. Yes. And what is the wall? Wall is thalamus? Yes. In that way, that way only, thalamus is acting as a relay center. All the sensory stimulus coming from peripheral sense organ and motor signal arising from the salivary cortex pass through thalamus, agree, dear? Tell me. Yes, sir. Hypothalamus, what is hypothalamus? It is situated in the base of third ventricle, it is situated in the base of third ventricle, agreed? Function, it acts as thermostat, hunger center, thirst center, sexual drive, and it is having endocrine functions also. You people know that it is going to control the pituitary gland, yes or no? Everyone? Yes, sir. That is hypothalamus, please write it down. That is hypothalamus, please write it down and come back in a minute. I am coming back in a minute. Yes, everyone. Are you done? Sir, just a minute. Yellow color, no? Done, everyone? Yes, sir. Yes. Now next thing is limbic system. Actually, as I have told you, the example of water melon, that is a, you can say, analogies only, not exactly. If you will remove the white part, that you consider that white part as cerebral cortex. So, if you will go down, go down into the, you can say below the cerebral cortex, you are going to find subcortical area. What? Subcortical area, in that there are many groups of nucleus, groups of nucleus. What is nucleus? Nucleus is collection of cell body into the CNS or in the CNS, okay? That is nucleus only. These are the nucleus that are there. Agreed, dear? Everyone? Agreed, everyone? Yes, sir. They are amygdala, ipuk, tempas, etcetera. You see, this is amygdala, okay? And just give me a minute here. The important call is there. Just a minute. Yes, everyone? Can you see, if you consider this as a tuning fork, you can see, ipuk, tempas is at the base. Yes or no? This is a tuning fork, no? This is the tuning fork, ipuk, tempas is at the base. Yes or no? Am I audible? Yes, sir. Yes. So, they are there. That is the part of, you can say, limbic system, limbic system. Amygdala is, you can say, it is more responsible for the emotional thing, for anger, for rage, etcetera. And ipuk, tempas is going to convert short-term memory into long-term memory. Yes or no? ipuk, tempas is going to convert short-term memory into long-term memory. Agreed, dear? Agreed, everyone? Tell me. Yes, sir. Done? So, you people can write this thing, limbic system. Especially, amygdala along with limbic system, along with hypo thalamus abagundates, sexual behavior, emotional reaction, and motivation. Agreed, dear? Everyone? Done? Just a minute, sir. Done, sir. Done, everyone? Now, the midbrain. Everyone? Are you done, dear? Are you done? Please let me know. Here, the midbrain. This is the posterior part of your brain. This is the posterior part of your brain. Can you see four round swelling over here, here, here, here and here? Can you see that? Yes, sir. Yes. That is known as corpore, quadricemia. By the word, quadricemia is used because it is four swelling. The upper two is known as superior colliculi and the lower two is known as inferior colliculi. Yes or no, dear? Superior colliculi is for visual reflex and for hearing reflex or acoustic reflex, inferior colliculi is here. Agreed? Tell me yes or no. For visual reflex, superior colliculi is there and for acoustic reflex, inferior colliculi is there. Agreed? Say yes or no. Yes. Yes. Midbrain is there. It is consisting of four round swelling, the corpore, quadricemia. Okay? Out of that, the superior two is known as superior colliculi and the inferior two is known as inferior colliculi. It is there for visual reflex and acoustic reflex. Acoustic means hearing reflex. You already see. Done, sir. Then, dear, this is superior colliculi and inferior colliculi. This is your middle brain. Regarding the brain, we have read most of the things. Okay? We have read most of the things, like CO2. Ponds means bridge. Bridge. It connects cerebral cortex to cerebellum. It acts bridge between them. Getting my point. And it connects other part of the brain also. It is having pneumotexic center and apnoistic center that we have read in regulation of respiration. Yes or no? Yes or no? Pneumotexic center and apnoistic center. We have read in regulation of respiration. Both of these centers are responsible for regulation of respiration. Agreed? Everyone? Could you just tell the function of apnoistic center again? Apnoistic first center is there for. It prolongs. It prolongs inspiration. If it will keep on working, it will increase the duration of inspiration. Agreed? Yes, sir. Got it. Yes. High in the brain. In high in the brain, the metal of oblongata part is going to have respiratory rhythm center, cardiovascular system, the vomit center, and it is the seat of your involuntary activity. Vomiting is also known as MSS. Hence, another name of vomit center is ametic center also. Agreed, dear? Yes. Cerebellum is the second largest part of the brain. It is made up of two cerebral hemisphere. And it is most affected part by alcohol. So, once after alcohol intake, gait or pattern of walking is going to be disturbed. This gait is gait. It do not initiate movement, but helps in ordination of movement. Getting a point. Movement is going to be initiated by which part? Movement is going to. Yes. Yes. Yes. Very good. Sir. Yes. What does the pneumotoxic center do? Pneumotoxic center is going to reduce the duration of inspiration and expires on as well. What it will do? It will deteriorate, but decrease the duration. Yes, sir. Done, sir. Done, dear? Now, one thing is there. One thing is there. Let's see over here. The cerebellum is consisting of, like you are cutting, you are cutting it from here, here and watching it from this side. Because cerebellum is also going to be consisting of two lobes. So, let's see over here. Two lobes. It will be divided into following lobes. These are known as lateral lobes. The central part is known as varmice and the, these two are circular lobes. See, this structure that is there, it represents a junction of white matter and gray matter. So, this structure is known as arbor viti. Okay? And if you will see over here, you will see over here, you all can see. Cerebellum is connected to different part of brain by cerebellar peduncle. This is the superior cerebellar peduncle. What? Superior cerebellar peduncle. This is the inferior cerebellar peduncle. And this is the middle cerebellar peduncle. Can you see? The superior cerebellar peduncle is connecting the cerebellum to which part of the brain? The superior cerebellar peduncle is going to connect the brain and it is going to connect to which part of the brain? Hepatalamus. Is it midbrain? Yes, sir. Middle one is going to connect it to the bones and the inferior one is going to connect it to the middle of lung data. So, this thing is written over here only. Any more point? That's all. About the parts of the brain. Sir, could you show the arbor viti in the diagram above? Is it visible? This one, this blue line. Sir, is it visible at the brain diagram? No, it is not visible over here. Let's see. Let me check over here. Yes, sir. Let me check over here. Actually, it is going to be shown in, okay. See, you can observe a bit over here. In this view, you will be able to see like that. Okay. I have seen in this view. Yes, sir. Got it. Done, everyone. Sir, just a minute, sir, labeling. Okay. Done, sir. Done, everyone. Let's see here. Let's see what I wanted to tell you all. Ventricles of brain. Ventricles of brain. Ventricles of brain. Let's see. Can you understand which section is this? Which section is this? This section passes from one ear to another ear. Okay. Getting a point. The plane which is cutting or you can say frontal section is there. Okay. Not understood. Understood, sir. See, I am cutting the brain. I am cutting the brain from here and watching it from this side. Every, every dear. Yes, sir. You are going to get this kind of structures, this kind of structure. Okay. See over here. See over here. Before going into ventricles, we should be doing covering of brain. Covering of brain. Just a minute here. Could we understand the complete? Can you see over here? Covering of brain. That is known as managers. What? Managers. I am moving it to some other end. This is not. Let's see. Let's see our important structures. Covering of brain. Why I am teaching it over here because it is connected to the topic ventricles of the brain. You see. The covering of brain is known as managers. Yes or no? What? Managers of brain. Agreed? No issues? It is known as managers of brain. Agreed? It is. There are three managers. Durometer, Arachnoid and pyrometer. Durometer, the arachnoid membrane and the and the pyrometer. Yes or no? Yes, sir. Durometer is true. Durometer is true. One is the outer one and one is the inner one. Outer one is known as outer one is known as parietal durometer, which is when to fuse to cranial bones and inner one is known as visceral durometer, which is when to fuse to brain. You can say arachnoid membrane. Agreed? Everyone? Everyone? Inflammation of managers is known as meningitis. What? Inflammation of managers. You keep on hearing the meningitis had happened. That is what? That is inflammation of managers. That is inflammation of managers. That is meningitis. Agreed? Everyone? Now you see. Now you see. Durometer, this white structure is the cranial bone. Yes or no? Cranial bone. This white structure. Everyone? And attached to it are yellow structure or orange structure. That is the parietal durometer. And this blue one is known as visceral durometer. Agreed? Visceral durometer. And the parietal durometer and visceral durometer is fused everywhere. The parietal durometer and the visceral durometer fused everywhere except at places that is known as venous sinuses. That is known as venous sinuses. Agreed? Yes sir. Agreed? That is known as venous sinuses. No issues? Now below that this red structure is there known as arachnoid membrane. Can you observe? Arachnoid membrane and below arachnoid membrane is a structure that is known as pyrometer. This yellow structure. And pyrometer is situated just outside the brain. Yes or no? This is brain tissue. Agreed everyone? Do you people agree? Say yes or no? Yes sir. Say yes or no? Yes. You people agree to this. So this is the pyrometer and the brain tissue. Agreed? Now can you see arachnoid membrane is folded in front of venous sinuses? That is known as arachnoid willy. What? That is known as arachnoid willy. Yes or no? Yes sir. Arachnoid membrane is fused. It is forming a finger like projection in front of venous sinuses. That is known as what? Arachnoid willy. Agreed dear? Yes sir. Everyone? Yes sir. Agreed everyone? So this is there. And one thing. Till meningitis is involved it is meningitis. Once the brain tissue will be involved it will it will become encephalitis. Once the brain tissue will be involved it will become encephalitis. Agreed dear? Tell me. Yes sir. No issues? No issues? So you people can write down all these definitions. Now what is the name of a space that is present between the present below the durometer? Durometer. It is known as subdural space. Which space? Sub-dural space. It is the space present between durometer and arachnoid membrane. It is the space present between durometer and arachnoid membrane. Yes or no? Tell me. And yes sir. Below the arachnoid membrane the space that is there is known as sub-arachnoid space. The space is present between arachnoid membrane and the pyrometers. It. Getting one point. In sub-arachnoid space what is present? Cerebro, spinal, fluid is present. Agreed dear? Do you people agree with all my points? See over here. Please see to it. Do you people agree with all my points or not? Yes sir. Yes sir. Right. Because how yes sir is going to move in that both is going to have roles. That is why I am teaching people over here. Otherwise I would have thought in just giving one. Sir could you show the diagram for a minute? We are done sir. You can scroll down. Done everyone? Just a minute sir. Yes sir. Just a minute. Sir could you scroll up for a second? Done sir. Yes. Let's see dear. Let's see. In case of brain there is no space between parietal durometer and the cranial bones. So epidural space is absent. Agreed? In the brain. What is there? Epidural space is absent in the brain. But in a spinal cord it is present. Agreed? This note. Can you people recognize? Can you people recognize? Yes sir. Yes. Let's see. We'll be talking about ventricles of the brain. Let's see dear. Ventricles of the brain. Let me take that and otherwise I will forward it. Let's see. Can you all see this thing? If you will cut the frontal section you are going to have two where you can say you are going to have one hollow space inside each cerebral hemisphere and they are known as lateral ventricles. Agreed? They are known as lateral ventricles. Here is the third ventricle. What? Third ventricle. And here is the fourth ventricle. Yes or no? Can you people understand? Yes sir. Lateral ventricle and third ventricle. Sorry, sorry. Lateral ventricles and third ventricle. This is fourth ventricle. Yes or no? Here is the coroid plexus of the brain. What? Coroid plexus of the brain. What? What is there? Coroid plexus of the brain. Agreed dear? What is there? Coroid plexus of the brain. Yes or no? From there CSF will be formed. What? CSF will be formed. Agreed? And from the coroid plexus CSF is coming into which ventricle? Lateral ventricle? Yes sir. From the lateral ventricle it is moving into third ventricle with the help of a foramen that is known as foramen of monorho. What? Foramen of monorho. So now it is there in the third ventricle. From third ventricle to fourth ventricle it is coming through the cerebral equiduct or another name is equiduct of sylvius. Later on it is written. So which structure is going to connect third ventricle to the fourth ventricle? Which structure is going to connect third ventricle to the fourth ventricle dear? Cerebral equiduct. Yes or no? It is similar. Okay. Same covering is there for brain as well as spinal cord. Agreed? Yes sir. Yes. So what have I told? I told you that third ventricle and fourth ventricles are connected through which structure? Cerebral equiduct. Cerebral equiduct. Yes. You are right. It is connected through cerebral equiduct or equiduct of sylvius. Now you see the CSF is formed from the coroid fluxes of vein. It is going to lateral ventricle. From lateral ventricle to third ventricle it is moving through foramen of monorho. Yes or no? It is moving through foramen of monorho and from third ventricle to fourth ventricle it is moving through. Cerebral equiduct. Yes. In fourth ventricle there are few foramens. The median foramen that is situated in the center is known as foramen of mesendi and two lateral foramens are known as foramen of lucca. What? Foramen of mesendi and foramen lucca. Yes or no? Through them the CSF will escape to sub-recnoid space. The CSF will escape to sub-recnoid space. Yes or no? Yes sir. And I have told you already CSF is present inside the sub-recnoid space and at that place a recnoid willy was there? A recnoid willy was there? Yes sir. That will take up that CSF and put that into cranial venous sinus. Yes or no? Cranial venous sinus. Agreed? Dear tell me? Yes sir. Tell me everyone? Oh yes sir. So from the fourth ventricle it will go to the? Sub-recnoid space. It will go to sub-recnoid space. From sub-recnoid space it will be taken up by a recnoid willy and will be put will be poured inside will be poured inside venous sinus and from there it will return to the blood circulation. So CSF is getting on from the blood only and it is returning to the blood also getting my point otherwise what will happen? It will keep on if there is any obstruction in the flow getting my point. The CSF will keep on accumulating will lead to increase in intracranial pressure and due to that only what will happen? A condition will develop that is known as hydrocephalus condition. Yes or no? Agreed? Everyone? Sir how is the fourth ventricle connected to the sub-recnoid space? Through foramen of mesendi and foramen of looker. You just imagine take a pipe wrap two three membranes around that okay make a hole in the pipe getting my point it can go to the outer space no? So the foramen is a cavity in the p-armator? Yes it will it will pierce through p-armator also. Yes sir got it yes agreed so this is there and you can see over here that cerebral duct is passing through mid-brain yes or no? Yes sir yes you can draw this diagram. So with the accumulation of cerebral spinal fluid will the toxins also accumulate in the brain? With the toxins that the fluid carries away from the brain will they also accumulate? No the toxins all the things you cannot call that toxin toxin is not usually present that is excretory matter it is providing nutrition and taking up things from there. So so will it cause brain damage if the if hydrocephaly is continuous? Yes of course. Yes sir got it. Sir so hydrocephalus is just increase in the intracellular pressure because of CSF right? Yeah what? Yes it is due to increase in intracranial pressure. Pressure inside the brain is increasing okay everyone? Oh excuse me sir yeah so I heard of a case where the cerebral spinal fluid leaked through the nasal cavity of a person for many years. Actually what happens there may be some damage in the bones cranial bones or some that kind of development may have may have happened. Agree to my point? Yes sir that can leak. Sir from where exactly does it travel to the nasal cavity like which bone? Actually actually actually you will see the base of cranium having many foremen having many foremen yes or no? Yes sir so does it leak through one of them? Dear am I audible now? Yes sir. Yes actually electricity? So sir I was asking if the CSF leaks through one of the foremen you mentioned? Yes yes if yes at the base of the skull or cranium actually there are many not only one there are many foremen so if some damage to the brain is there or injury to the managers is there what will happen in that case? So what are the consequences of CSF leak? What are the consequences? It can lead to you can say first consequence is the CSF is leaking because of actually injury is there not at any place getting my point information will be there getting my point if CSF is leaking in that case what will happen inside the brain CSF will decrease yes or no so all those things will be there main problem that is not going to happen on its own some injury will be there okay? Yes sir. Yes I got it yes yes I think electricity has gone okay and time for break is also there so let us take 15 minutes break after that we will start okay? Yes sir. Yes it is there no issues so after break I will let you write okay take a break till Wi-Fi starts. Yes sir. Okay let's see dear are you people there everyone? Yes sir. Yes you can see this you can write it down done everyone are we done with this? Just a minute sir. No you write down because that is a important concept done. Sir could you scroll down a bit for the points? Yes pathway of movement of CSF I have written the same thing that I have told you so could you scroll up a little bit done sir are you done with all these things? Sir just a minute. Yes sir. Right done sir. That's all with brain now we will be moving to spinal cord spinal cord if you will see this is the longitudinal section of spinal cord this is your medulla oblongata this part is medulla oblongata and in the base of the cranium there is a foramen known as foramen magnum foramen magnum through that through that only through foramen magnum only what happens the spinal cord comes out and continues like this and continues like this. Okay the lower portion of lower portion of spinal cord is conical and known as conus medullaris what is there known as conus medullaris and you see it is stretched by or keep in place by a fold of durometer that is known as phylum terminus as this is fold of durometer only so it is non-nervous in it is a non-nervous structure yes or no tell me yes sir it is a non-nervous structure so you people see this is the structure that we are looking for what is the function of phylum terminus again it is just you can say keeping the spinal cord in place otherwise it will it will go up and down no it is the lower attachment only it is the lower attachment only so what is it anchored to anchored to the vertebral column yes done everyone just a second sir yes so what's c1 l1 and mo c1 is first cervical vertebra mo is medulla of lungata and l1 is first lumbar vertebra understood yes sir done everyone no doubt no doubt let's see this is the cross section I have cut it at this level and now I am watching it see as far as cerebral cortex is there is concerned I have already told you this thing that in the brain cerebrum outer part is made up of gray matter and the inner part is made up of white matter which is opposite in case of spinal cord yes or no the inner part the yellow color thing that is there is made up of the yellow color thing that is there that is made up of gray matter and these areas are made up of white matter These areas are made up of white matter. Let's see. And these areas are made up of white matter. Agreed? These areas. Read everyone? No doubt? Yes. No doubt in this? This thing we have already discussed. Now you see. This is known as, this is known as, this is known as the dorsal root, dorsal horn actually. What? Dorsal? And this one, this side I am, I am depicting this side. This is known as ventral or agreed? This is known as ventral horn. Agreed dear? Tell me. Dorsal horn and ventral horn. From the dorsal horn, this blue color structure is arising. That is known as dorsal root. What? Dorsal root. And from the ventral part, the structure that is arising, this is known as ventral root. What? Ventral root. Agreed? Agreed dear? The dorsal root and the ventral root. Yes or no? Yes or no? Yes sir. Yes or no? Now see. There is a nerve fiber that is originating from a receptor entering inside the dorsal root. Means it is taking impulse from peripheral organ towards the spinal cord. Yes or no? So this will be known as afferent fiber. Which fiber? Afferent. Afferent fiber. Agreed my dear? Getting my point dear? Tell me. That is known as afferent fiber. Now you see. This afferent fiber is going making a synapse over here. Making a synapse over here. In this area you can see here. It is making a synapse with this red color neuron. Yes or no? Yes sir. And it is coming through the ventral root. Means through ventral root, the nerve fiber is coming from CLS2. What? CLS2 towards the peripheral organ. Yes or no? Yes or no? Tell me. So one is known as dorsal root. So can I say dorsal root is sensory and ventral root is motor in nature. Can I say that? Yes sir. Dorsal root is sensory and now see. And one more fiber is there. It is there for sympathetic nervous system. Yes or no? Ramos communicates is for autonomic nervous system to be precise. Yes or no? So all the fibers of autonomic nervous system, whether it is sympathetic or parasympathetic. That is what? Whether it is sympathetic or parasympathetic. That is what? Sympathetic or parasympathetic. That is what? Tell me dear. That is motor in nature. Yes or no? Yes sir. And you see, if you bundle all these nerve fibers together, you are going to get the spinal nerve. If you will bundle all these nerve fibers together, you are going to get the spinal nerve. Here is two kind of fiber always in the spinal nerve. So spinal nerve is sensory in nature or motor in nature. Mixed. Mixed. So all the spinal nerves which is 31 pair are mixed in nature. Are you able to understand this thing? Where I have told you pseudo-unipolar nerve fiber. At that place only I have told you dorsal root. In the dorsal root ganglion, dorsal root ganglion is the part of dorsal root which is swelling in the dorsal root. That is known as dorsal root ganglion. Yes or no? It is made up of pseudo-unipolar neurons. Agreed? Tell me dear. Yes sir. Everyone. No issues? No issues? No issues sir. So what is it? Communicants? Ramos communicants is a nerve fiber that is going for autonomic nervous system. Okay? Autonomic. Sympathetic. Yes or no? That is known as Ramos communicants. Agreed? Can you observe this thing? Please draw it. I am coming back in a minute. Done everyone? Are we done dear? Yes sir. So could you just repeat what Ramos communicants is again? Ramos communicants is a motor or autonomic nervous system. Yes or no? Yes sir. Got it. Just a minute dear. My stimulating has stopped. Just a minute dear. Due to some reason it is not getting started. I am again starting it. Am I audible to you? Done everyone? Let's see. Now next thing is reflex action. What is reflex action dear? It is your sudden response to any noxious stimuli. Your sudden response to any noxious stimuli. It is protective and usually processed at spinal cord. I have written usually not always. It may be processed or it may go to the brain also. But the kind of reflex is known as cranial reflex. But cranial reflex is usually very slow in nature. So where protection of your body is required, the action should be very fast. Yes or no? The action should be very fast. Yes or no? Now this is a spinal cord. Just see. Here is a receptor. From receptor our friend fiber is going. Yes or no? Now see. Here. How many kind of things are happening? Done. See. Can you imagine a single neuron is secreting two kind of neurotransmitter? Can it happen? Can it happen? See dear. The thing is when you are getting some noxious stimuli like this. If you are getting some noxious stimuli like this. Okay. And you are trying to withdraw your hand. One muscle is going to contract. But one muscle is going to contract. Another muscle has to relax. Yes or no? Then only movement at joint can happen. Just try to think about your, you can say, hand only. Elbow joint. If I have to take my hand away. In that case, biceps has to contract and triceps has to relax. Yes or no? Then only a genuine movement can occur. Agreed dear? Yes. Tell me. No issues? So here. Our friend fiber is there. See one synapse is over here. Getting my point. And that synapse you can observe. It is direct with this red fiber. Yes or no? Direct. Agreed everybody? Yes. And here you can observe orange color neuron. One synapse is over here. Another is over here. So how many synapse are there? How many synapse are there? There are two. More than one. So this small orange color structure is known as interneural. Okay. This pathway will come and will lead to contraction by factor one. This muscle. And this pathway will come and will act on the factor two. Two relax. Means one pathway is excitatory. Another pathway is inhibitory. Agreed dear? Yes sir. One pathway is excitatory. Another pathway is inhibitory. Agreed dear? So what can you think? The excitatory pathway is monosynaptic or or polysynaptic. Excitatory pathway. Only one synapse is there in excitatory pathway and here? Yes sir. So it is monosynaptic. In inhibitory pathway. Getting my point. In either of the pathway. Either it is excitatory or inhibitory. One pathway will have interneural. At least one pathway will have interneural. Both can have. Yes or no? That's here. So reflex pathway consists of a receptor, a friend fiber, an interneural, an efferent fiber and an effector. This is known as reflex pathway which is not essential. It can be there. It cannot be there. It is interneural. You see it is missing in excitatory pathway but it is there in inhibitory pathway. So it is conditioned. Agreed everyone? Yes sir. Then draw this diagram and just coming back. Then everyone, the reflex pathway is done. Am I audible? Yes sir but just a minute. So could you just zoom in on the dial? Are we done? Yes. You can write reflex pathway. So could you just show what the glycine and astrylcholine thing you've written is? Like where they're released? Yes. I'm going to let you know. Yes. Just a minute. Done sir. Done. Now see. Types of reflex arc. It can be monosynaptic. It can be polysynaptic. I think again the screen mirroring has stopped. I don't know why this is happening in the later part of the class. Usually it do not happen. Just a minute. Let's see. Types of reflex arc. Types of reflex arc. Monosynaptic and polysynaptic. As I have told you, if only one synapse is there in the pathway, means interneural is absent. Then the direct synapse between afferent fiber and efferent fiber. That is known as monosynaptic reflex arc. And if interneural is there, that is known as polysynaptic reflex arc. Yes or no? Getting my point. One more thing is there. One is conditioned reflex. Another is unconditioned reflex. Conditions, what happened? There was a scientist, Ian Pavlov. What has he done? What has he done? Pavlov has done. He has, you can say a dog was there before giving that dog the food. You can say Pavlov used to ring the bell. Pavlov used to ring the bell. Yes or no? Pavlov used to ring the bell. Done, dear? Done. What he observed? After some time, even if the food is not given, even just after ringing the bell, you can say dog starts salivating. Based on that, there are two kinds of reflex. One is unconditioned, one is conditioned. Unconditions is, in this previous exposure is not required, like knees are reflex. Or if you are going to touch anything harmful, you will withdraw your hand. But salivation after seeing a tasty food, that is conditioned reflex. Because if you have not tasted the food earlier, you are not going to salivate much. Yes or no? So this is there. You can write now. Excuse me, sir. Sir, in conditioned reflex, is there any case where conditioned reflex can, conditioned reflex? What? Is there a case? Yes, is there a case where conditioned reflex can inhibit or dominate? No, actually conditioned reflex are not of that kind. Getting my point. Many things, try to understand my point. Many things are there. Like you are going to have something noxious, like fire is there, some chemical is there. You will feel the pain. But for all the reflex, you are not going to feel the pain suddenly. Or that can be present also. Getting my point. That can be present also. So without knowing that thing, how your body is going to react? Tell me. Understood? Yes. Unconditioned is because that is absolute. That is objective. That is not subjective. It is present all the time. Yes, got it. Excuse me, sir. So is conditioned reflex and Pavlovian reflex the same? Yes. Actually, Jan Pavlov was the scientist who has, at any moment, who has done all these experiments. So, sir, both of them are different names for the same reflex, right? Yes. Name of the scientist was Jan Pavlov. Yes or no? Yes, sir. Done, sir. Done. So that is about the reflex sense. Now, we will talk about sensory. Let's see here. What happens? What is your, you can say, what is your receptors are? What are the receptors? What is the function of the receptors? It converts one form of energy into another form of energy. Yes or no? It converts one form of energy into another form of energy. Done here. Yes, sir. It converts one form of energy into another form of energy. What happens? You people have a little bit of idea about mechanism of hearing. Because see, all your, you can say, everything, all your senses are going to be processed inside the brain only. Every, all your senses are going to be processed inside the brain only. Yes or no? All your senses are going to be processed inside the brain only. Done, dear? Yes, sir. It is processed inside your brain only. Every time. So, what will happen? What will happen? Any energy that is coming, that has to be converted into what? That has to be converted inside, converted into electrical energy, no? Because one knows, one neurons, conduction of electrical energy is possible only. Agreed? Tell me? Yes, sir. Yes. So, what receptor do? Any energy is coming, receptor is converting that energy into electrical energy. Agreed? So, that is acting as a transducer. In physics, you may have heard about transducer. It converts one form of energy into another form of energy. Yes or no? Like in ear, rubbing of hair cells against factorial membrane is there. Means, mechanical rubbing is there. Means, mechanical energy is converted into electrical energy. Yes or no? Yes, sir. Yes. Inside your eyes, inside your eyes, what happens? The light energy is converted into electrical energy. Inside your tongue, the chemical energy is converted into electrical energy. Agreed? Yes, sir. Done? Done. Yes, sir. So, if chemical energy is converted into electrical energy, that will be known as chemo receptor. Everyone, now see, here is classification of sense organs. One is extero receptor, one is proprioceptor and one is visceral receptor. Extero receptor is the external sense organ, which perceive our environment, which perceive our environment. Proprio receptor, they are present in joints, tendons, skeletal muscles. And visceral receptor is present internally. Done? So, these are, this classification is based on the location. Agreed? Done? Yes, sir. Everyone? Just a second, sir. Sir, so muscle cramps are perceived by proprioceptors, right? Yes. Muscle cramps, actually, it is there to perceive your, you can say, it is there to perceive your position. Okay? Whether you are standing, you are sitting, whatever kind of things are there, that is going to be perceived by your muscles. Yes, sir. Done? So, means proprioceptors, joint movement, everything that you are doing. Yes. Yes. Let's see. According to a stimulus, they receive, okay? Receptors are mechanoreceptor. As I have already told you, mechanoreceptor means what? Mechanical energy is converting mechanical energy into electrical energy. And what all kind of mechanical energy can be there? Let's see. Here, tango receptor, business corp cells, Merkel's disc and a Pascinian corp cells are there. Phono receptors, organ of prototype, stator receptor, it is Krista and Makula. LJC receptor, it is free nerve-ending. Proprio receptor, it is responsible for position of the body. It is Golgi mojoni organ. Reo receptor, it is a lateral line system. You know, fishes are like this. The whole body is covered by non-living plastic-like scales. Yes or no? Yes, sir. Yes, sir. If nothing will be there, no? This is lateral line system, okay? Lateral line system. If this will not be there, what will happen? This will not be able to, fish will not be able to perceive anything in the water. It will not be able to perceive anything in the water. So, it is the sensory organ of the fish. Agree, dear? Yes, sir. No source. This is lateral line system in fishes. That lateral line system is going to have neuromast cells, neuromast cells that you people can remember, okay? Then photoreceptor can be there. It is there for light. It is the retina, the chemoreceptor, your olfactory receptor for smell and gastroreceptor for taste. And one is thermoreceptor. These two are there. And bulb of cross and raffinate organ that is there. Okay? You people can write down these things. Rest we will be discussing in the next class. I think by that time it will be over. Done. And, sir. Done. Sir. Yes. So, what are the examples for the thermoreceptors, sir? Thermoreceptors. And the bulb of cross and raffinate organ are the names. And the bulb of cross and raffinate organs are the names. Yes, sir. Done, everyone? Just a second. Done, sir. Bye, everyone. Good night. Thank you, sir. Okay, I hope you people have understood. Yes, sir. Yes, sir. Yes. Thank you, sir. Yes, rest we will discuss in the next class. Yes, sir. Thank you, sir.