the brain right it's amazing how many functions the brain does both consciously and subconsciously today we're going to be talking about the ait's version 7 portion of the exam human anatomy and physiology and we're going to be focusing on the neurological system let's get started structurally the nervous system is divided into two main regions we have the central nervous system and the peripheral nervous system the CNS is comprised of the brain and the spinal cord functioning as the primary Command Center for processing information in contrast our pns includes all of our nervous system elements such as our nerves distributed throughout the body the pns gathers sensory information and relays it to our CNS which then processes that data and coordinates motor responses and regulates bodily functions as we look at the brain we're going to categorize it into three main regions we have the hindbrain the midbrain and the forebrain starting with our hindbrain it is composed of three main areas we have the medulla ablang the ponds and the cerebellum the medulla ablang which is this region right about here regulates vital functions including things like breathing blood pressure and heart rate the ponds also supports these functions and help coordinate communication between our forbrain and the cerebellum and then lastly our cerebellum plays a key role when it comes to balancing and coordinating movements an easy way that I like to remember these three things is is the medulla manages the pawn passes and the cerebellum coordinates as you know the medulla manages essential bodily functions that we talked about when it comes to motor control monitoring heart rate as well as modulating breathing the pwns passes messages between the brain and the body and it plays a critical role when it comes to the patterns of breathing and participates in our sleep cycles and then lastly the cerebelum coordinates complex voluntary movements it controls balance and IT calibrates muscle activity to ensure smooth and balanced motion next up let's talk about our midbrain which is located deep within the brain it's essential for maintaining alertness and managing our sleep wake cycle as well as overseeing some of our motor activities an easy way that I like to remember how the midbrain functions is I like to use pneumonic mid controls which stands for movement involvement in the sleep wake cycle and detection of auditory and visual reflexes starting with movement the midbrain is involved in motive movements and coordination particularly eye movement and other reflexive responses when it comes to the involvement of our sleep wake cycle it plays a crucial role when it comes to maintaining our alertness and regulating that sleep wake cycle and then lastly we have detection of auditory and visual reflexes the midbrain processes that auditory and visual signals contributing to the reflective responses we get whenever we're introduced to a stimuli next up we have the four brain which contains our cerebrum which is the largest and most developed part of our brain it features a distinct fissure that actually runs down the middle of our brain dividing it into two hemispheres we have the left hemisphere and the right hemisphere but what do we mean by it's the most developed part of our brain well primarily the cerebral hemispheres houses the primary motor and sensory cortices when I mention the word cortices I'm referring to the plural form of Cortex the cortex is simply the cerebrums outer layer it's about 1 to 5 mm thick and it's actually composed of gray matter as you can see here in this picture when we're examining a neuron there's a few key components that we need to identify we have the cell body we have the axon and we have the axon terminal the axon terminal is typically going to connect to another neuron what's important to note is that the axon is enclosed in this myON sheath which is made up of fats and lipids and they appear to be white therefore in the brain we have gray matter which consists of the neuron cell bodies in the area where the synapsing actually occurs while white matter is primarily composed of those axons in the milon sheets this distinction is crucial because gray matter is where information is integrated and processed essentially where the brain makes sense of the incoming data in contrast white matter acts like highways simply facilitating that rapid transmission of signals from one area of the brain to another so as we talked about before within our cerebral hemispheres lies the primary motor and sensory cortices representing the highest level of neural activity for example the primary mottar cortex located in our frontal low if you take a look here that's that purple area that deep purple area right there this is the area that's crucial for initiating voluntary or conscious motor movements for example if you decide to start walking this initiation actually occurs right here in our brain marking it as the highest level of which motor activity is controlled similarly the sensory cortex processes incoming information from both our external and internal environments enabling us to consciously be aware of what's going on this actually occurs right here where you see this dark teal on our brain this area represents the highest level of sensory information integration for example when you t a hot surface it's that sensory cortex that processes this sensation alerting you of the Heat and enabling you to react appropriately to get your hand away from that hot surface within the cbal hemispheres we find association areas that augment the functions of both our primary motor and our sensory cortices these areas are going to integrate past and present information enabling comparison and contrast of what is already known this process is going to enrich our understanding SC in and providing us a deeper analysis of complex information for instance while the primary mottar cortex May initiate basic actions like walking it's really that Association area that enhances the capability by allowing the sequencing and planning of more intricate tasks so let's take for example if you were dancing in ballet or executing a series of martial art movements the association area of the mortar cortex would be engaged enabling the planet and sequencing of these more elaborate activities when we're examining the sensory cortex which is located up here in our parietal lob this Association cortices play a crucial role when it comes to helping you interpret the type of sensory information that you're going to encounter for example using the earlier example of touching that hot stove the primary sensory cortex alerts you of the sensation of heat but it's the association cortex that then further analyzes that information it assesses the temperature and considers whether it's merely just warm or scolding hot this area also draws upon past experiences like previous encounters with heat to help us identify and understand the sensation thus that Association cortex is integrated into our memories and current sensation it's going to Aid in our primary Stato sensory cortex the cerebral hemispheres are also going to serve as the foundation of our conscious experience when we become consciously aware of something it is because that sensory information or thought processes have reached our cortex as we discussed before this cortex is that thin layer about 1 to 5 mm thick enveloping the outermost part of our hemispheres it is within this critical layer that our Consciousness emerges allowing us to become more aware of the experiences around us while the deeper areas of our brain may receive sensory information or initiate decisions about motor movements these processes do not enter our conscious awareness unless they reach our cerebral cortex therefore for us to consciously be aware of Sensations thoughts and actions they must be processed through the superficial layer of our cerebral hemispheres this is where all elements necessary for conscious awareness are integrated and interpreted the cerebral hemispheres also house our lyic system which plays a crucial role when it comes to memory and the emotional dimension of behavior let's consider various emotional aspects of our daily life such as relating to eating relationships reproduction and the fight ORF flight response it's the limic system that influences all of these furthermore the lyic system is integral to the highest level of cognitive function found in our cerebral hemispheres cognitive functions Encompass activities such as planning making judgments experiencing emotions reasoning and ensuring that behavior is appropriate to the context much of our cognitive processing occurs in the frontal low specifically known as the prefrontal cortex if we have damage that occurs in this area it is going to significantly impair our Behavior planning and other cognitive functions highlighting its importance in managing complex behaviors and decision-making processes and lastly we have our occipital low which is back here and we have our temporal lobe which is right here the aital lob's primary functions include processing integration and interpretation of visual and vision stimuli this area houses the primary visual cortex where visual signals are received from our retinas and our temporal lobe is important for processing auditory information and it's home to our primary auditory cortex it plays a key role in the formation of our longterm memory it's also involved in speech comprehension through our wori areas which is on the left temporal lobe and it also assists in recognizing and processing emotion and language so I wanted to give you an easy memory trick when it comes to remembering what each lobe does so we're going to start with the frontal lobe I want you to think forhead frontal lobe it's symbolizing our deep thought and decision-making processes so when it comes to the parietal lobe I want you to associate it with a parachute because it's covering the top part of our head and it's related to the sensory input from our body below our occipital low which is located here in the back connects to our Optics and our ocular focusing on our role when it comes to vision and then lastly when it comes to the temporal low which is kind of right here on the sides I want you to link it to Tempo when it comes to music reflecting on its connection when it comes to hearing and rhythm in speech and memories so now that we've covered the central nervous system what about that peripheral nervous system from a functional perspective the pns can be further categorized into two main parts we have our somatic nervous system and we have our autonomic nervous system the somatic nervous system is primarily responsible when it comes to the motor functions of our skeletal muscles both encompassing the voluntary actions that are under our conscious control and the somatic reflexes which are not on the other hand we have our autonomic nervous system which primarily manages our body's internal environment regulating functions related to to our gastrointestinal expiratory and endocrine systems as well as smooth and cardiac muscle activities it also governs autonomic reflexes and the autonomic nervous system can indeed be split even further yes there's more divisions taking place we have the sympathetic nervous system and we have the parasympathetic nervous system the sympathetic nervous system which is the shorter name of the two is easy to remember because it's associated with the rapid fight or flight response instead of that typical example of running from a bear let's say you're suddenly standing in front of a vending machine your snack has just gotten stuck and it's Out Of Reach while there's a long line forming behind you for those who also want to get some snacks this frustrating scenario could definitely kick that sympathetic nervous system into overdrive this reaction could increase your heart rate it could increase your respiratory rate and your digestive system well that's going to take a backseat to all other things that need to take place first I mean after all you're dealing with an immediate stress be it a bear or a rebellious vending machine digesting food is not your body's main priority now when it comes to our parasympathetic nervous system denoted by the longer word it's frequently referred to as our rest in digest system in this state your heart rate is going to slow down and digestion is going to occur in your body as it enters into that phase of rest and Recovery often the parasympathetic and sympathetic systems have inverse effects on on the same organs essentially balancing each other out in their regulation of bodily functions let's discuss the two primary types of cells found in the nervous tissue of both the Central and peripheral nervous systems that you're going to need to know when it comes to the te's typically when we think about cells in the nervous systems neurons are the first thing that come to mind while we do recognize that there are various types of neurons let's take a look at the basic structure when it comes to a general neuron as we talked about before a neuron houses a cell body which encompasses most of the neurons organel as well as its nucleus we also have things known as dendrites and these are branch-like structures that receive the signals from other cells and then next up we have our axon which is our long body right here and the way that I like to remember it is I like to think of the phrase axon away because axons are the long fibers that carry signals away from the neuron to other cells the point in which neurons communicate with one another is known as a synapse and that's done right here at the axon terminal another essential cell you're going to need to know are gleo cells structurally there are significant emphasis on how gal cells help hold neurons in place the word glea itself deres from the Greek word meaning glue however gal cells are far more significant than that some of these cells help maintain the chemical balance necessary for signaling between our cells and help sustain that blood brain barrier which prevents many substances in the body from entering our nervous system others produce myin sheath a protective coating that wraps around our neurons axons insulating them in enhancing signal transmission additionally some gal cells generate cerebros spinal fluid which not only protects our brain but it also plays a crucial role in maintaining homeostasis among other critical functions certain gal cells are integral when it comes to our immune function within our nervous system honestly these examples are just scratch ing the surface of the diverse and essential roles that these gal cells play within our body last for neuro let's break down neuron input and output and how they play a crucial role in how our bodies function first up we have our afferent neurons also known as our Sensory neurons they carry signals towards the central nervous system from our sensory receptors I like to think of afferent as admission or afferent arrives because they admit information into the brain and spinal cord from the body so again using the example we talked about before when we touch a hot stove our sensory receptors in our skin are going to detect this extreme heat it's those afferent neurons that are going to quickly carry that information to our brain signaling that something is painfully hot now moving over to our eent neurons these are known as our motor neurons because they carry signals away from the central nervous system to muscles and glands I like like to think of this as eperen exits because these types of neurons exit our brain and spinal cord to actually cause the action to take place so once our brain has processed the information received from our afferent neurons about the hot stove it needs to take action it's going to react it's these epher neurons that are going to carry the instructions from our brain back to the muscles of our hand telling them to pull away this is the motor response that's initiated by our e arent neurons I hope that this information was helpful in understanding the neurological system when it comes to the aits as always if you have any questions make sure that you leave them down below I love answering your questions head over to nurse Chun store.com there's a ton of additional resources available to you to help you Ace those ait's exams and as always I'm going to catch you in the next video bye