good morning afternoon evening night whenever you're watching this welcome back to the mr sim channel today we're going to be talking about unit 2 topic 6 of ap psychology the brain by the end of this video you'll be able to identify different key locations of brain structures you'll understand their functions and you'll have an understanding of different contributions made to our understanding of the brain and if all of that sounds good to you well smash that subscribe button hit that like button and let's get learning so it is no secret that the brain is one of the most important organs in your body it has over 86 billion neurons over 100 000 miles of axons and over 10 trillion synapses and consumes 20 of your body's oxygen those are some pretty impressive statistics if i do say so myself now brain research dates all the way back to the first century bc where hippocrates started speculating that a person's brain was split into two halves and each half was capable of independent processing now over time there have been many people have made significant contributions to our understanding of the brain but for time's sake i'm only going to talk about two of them carl wernicke and paul broca both looked at our brains and language paul broca first identified a region in the left cerebral hemisphere of the frontal lobe which became known as broca's area this area of the brain is in charge of facial muscles that are needed for us to physically speak broke a base's hypothesis off of case studies of patients who had damaged an area in their brain which resulted in the individual losing the ability to speak this became known as broca's aphasia which is the loss and ability to produce language while the individual may lose their speech they still are able to comprehend the language carl wernicke discovered the area in the cerebrum which is responsible for language vernicki created a model that looked at language he believed that the part of the brain known as wernicke's area located in the left temporal lobe creates meaningful speech while broca's area located in the left frontal lobe determines movement needed for vocalization and sends that information to the motor quartet if wernicke's area was ever damaged it would result in the person losing meaningful speech a person would still be able to say words and sounds but they would have no real meaning and they also would no longer be able to comprehend sounds or speech this disorder became known as wernicke's aphasia so the brain is part of the central nervous system and as we can see from research done by broca and wernicke each part of our brain is in charge of specific tasks the brain can be broken up into three major regions the first region is the hindbrain located at the bottom of the brain moving up from the base of our brain we have the smaller midbrain this part of the brain is difficult to see because it's surrounded by the last region of our brain which is the forebrain the forebrain is what most people typically visualize when thinking about the brain starting out the heim brain is made up of the pons the medulla oblongata and the cerebellum these parts of the brain allow us to survive by controlling our basic biological structure the medulla takes care of important autonomic functions these happen without us consciously thinking about them it's located right above the spinal cord and below the pond this part of the brain is going to regulate your cardiovascular and respiratory system on top of the medulla is the pons the pons is primarily a bridge between the different areas of the nervous system it connects the medulla with the cerebellum and it works with the cerebellum to coordinate movement the main functions of the pons that we're going to focus on this video is with sleep and dreams a tip for remembering the pons is to think of the pons as a pillow p for pillow and it's located on top of the bed b for brain stem next we have the cerebellum which is located at the base of the brain in the back the main function of the cerebellum is that it allows you to maintain balance and manage your coordination so you're able to walk straight in a line without tripping over your feet and you're able to scoop cereal into your mouth with a spoon instead of tossing it on your head it also plays a role with things that require practicing to improve such as playing an instrument or learning to ride a bike it helps your body remember how to perform those actions the cerebellum in latin is called the little brain since it's two wrinkled halves that look like a brain attached to the brainstem if this area becomes damaged the cerebellum would make a person's movements very unbalanced and clumsy very much like a drunk person who can't walk a straight line and since i've mentioned the term brain sim let's quick go into a couple specifics about the brain stem it's located at the base of the brain on top of the spinal cord it includes the medulla the pons and the midbrain if the brain stem is ever severely damaged the result is death because the functions of the brain stem is the autonomic function we also need to quickly talk about the spinal cord remember that the spinal cord is what connects your brain to the rest of your body it starts at the base of your brain and runs down the spine think about it like the information highway the spinal cord allows your nerves to send information from your brain to the rest of your body and vice versa all right so we talked about the hindbrain now it's on to the next region which is the midbrain this is on top of the brainstem and just right above the hindbrain this part of the brain is very difficult to observe since it's buried under the other parts of the brain and is very small in humans it's actually the start of your brainstem when thinking about the midbrain think about a relay station visual and auditory information is sent here and then sent to the appropriate structures of the brain the two important structures of the midbrain are the reticular formation and the reticular activating system the reticular formation is a structure that tunnels down the brainstem its main function is arousal in the awake and sleep cycle and if you damage this area you'll go into a coma so don't damage it this structure contains lots of neurons from different parts of the brain stem and coordinates reflexive and autonomic vital functions such as respiratory control as well as pain modulation the reticular activating system encompasses the reticular formation but it's also a network of nerves that run through the brain stem and out to the thalamus its function is to stimulate higher centers when something important happens that needs immediate attention for example when someone says your name it is screening and filtering the incoming stimuli and sending that information to the thalamus now so far we've spent some time talking about the midbrain and also the hindbrain which are responsible for our involuntary function now we're going to go into the forebrain which is in charge of our voluntary function the forebrain is the largest part of the brain it allows us to have complex thoughts and also behaviors the forebrain it consists of all parts of the brain except for the brainstem and cerebellum the term forebrain is a way to describe the region cerebrum is the name of the brain parts that are not the brain stem and the cerebellum which equal roughly about 85 percent of the brain the function of the cerebrum is all brain processes that aren't just for survival like complex sauce moving deeper into the cerebrum we have the cerebral cortex which is a thin outer layer of billions of nerve cells that cover the whole brain these neurons are called gray matter all higher cognitive functioning happens here inside of the cerebral cortex is the corpus callosum this structure is shaped like an arch that stretches from the front to the back of the brain it's made up of different nerve fibers that connect the two cerebral hemispheres this allows your hemispheres to talk and communicate with one another one trick to remembering this is to think about the corpus call oh some as calling the other hemisphere to communicate the cerebral cortex can be broken down into two different hemispheres a right and a left and this is where we get into our four different lobes the first level we'll talk about is the frontal lobe as the name suggests this lobe is located in the front of your brain it's actually right behind your forehead its function is higher level thinking and we can see there's two important areas of this low the first is the prefrontal cortex which allows you to have foresight judgment speech and complex thought this lobe will continue to grow and develop into your 20s this is also where your broca's area is located remember we talked about this area at the start of the video the second is the motor cortex which allows you to have voluntary movement and is located in the back of the frontal lobe and runs from ear to ear it's kind of like an arch the left motor cortex controls movement on the right side of your body and the right motor cortex controls movement on the left side of your body the motor cortex is represented by a figure called the motor homunculus this shows us a visual representation of the amount of brain area that's dedicated towards a specific body part what we understand from this visual representation is that more brain tissue is devoted to the body parts that are the most controlled by us like our hands and our mouth the next lobe is the parietal lobe which sits on the top of your head right behind the frontal lobe it's separated by the central sulcus the main function of this lobe is to receive sensory information it lets you understand different senses such as touch pain temperature and spatial orientation all right so remember how we talked about the motor cortex and how it sits like a headband from ear to ear as part of that frontal lobe well the somatosensory cortex is parallel and touching the motor cortex it's located in the front area of the parietal lobe and is in the front of the parietal lobes in between the parietal lobe and also the motor cortex the somatosensory cortex is part of the parietal lobe which allows you to register touch and movement sensation this is what is in charge of your skin the left sensory cortex control sensations for the right side of your body and the right sensory cortex control sensations for the left side of your body and of course just like we talked about with the motor homunculus there is also a sensory homunculus this is a visual representation of the amount of brain area that's dedicated towards a specific body part in relation to how sensitive it is to stimulate what we understand from this visual representation is that there's more brain tissue devoted to the body parts that are the most sensitive like our hands and tongue you'll notice there is a difference between the motor and sensory homunculus behind the parietal lobe is the occipital lobe this is the lobe that makes it possible for you to see this is located in the back of your head here you also have your visual cortex now if you're struggling to remember where this is located just try to remember the saying they've got eyes in the back of their head now the visual cortex is located in the bottom of the occipital lobe and your eyes do kind of an interesting thing when they process information the left side of your visual cortex is actually interpreting the information that comes in from the left side of each eye which is reading the right field of vision while the right side of your visual cortex is interpreting the information that comes in from the right side of each eye which is interpreting the left field of vision now up next is the temporal lobe which is located right above your ears on both sides this lobe helps you recognize faces smell hear noises balance and assist with memory this lobe consists of a few different parts first remember wernicke's area it's responsible for language and also comprehension it's located in the temporal lobe we talked about it at the start of this video located near wernicke's area is the angular gyrus which allows you to read words on paper and also transfer that information as an auditory form this is what allows you to process what you read also located in the temporal lobe is the auditory cortex which is located in the upper areas of the temporal lobe this cortex is what processes your hearing and is actually hearing what is happening from the opposite ear one last thing i wanted to highlight about the lobes is that they all have association areas these are regions of the cortex which connect the sensory and also motor area it allows us to have higher level thinking process our external information and lets the cerebral cortex communicate with different parts of the cortex association areas make up about 75 of the cerebral cortex all right the next structure we're going to talk about is the thalamus it takes all the different sensory information that you get every single second and sends that information to the forebrain to be interpreted so right now when you're watching this video the sound and the visuals are being picked up by your eyes and your ears and the thalamus is sending the sound information to the temporal lobes and the visual information to your occipital lobes allowing you to understand the information in this video the thalamus is a two-symmetrical egg-like structure at the top of the brainstem next up is the limbic system which is a ring-shaped group of structures between the brain stem and the cerebral cortex the function of the limbic system is emotions learning memory and some basic drive first up is the hippocampus this structure is surrounding the thalamus and it's inside the temporal lobe this area allows you to create memories this is how you learn new information and form memory remember this is where memories are created but not stored that's going to be important to distinguish next is your amygdala this structure is located at the end of each arm of the hippocampus two round clusters on the end of each arms to be exact this is where you get your emotional reactions from specifically fear anxiety and aggression under the thalamus is the hypothalamus which keeps your body balanced this allows us to have homeostasis this is what controls your drives thirst hunger temperature and of course sex the hypothalamus also works with the pituitary gland to regulate and control your hormones remember we talked about hormones and also the endocrine system back in our unit two topic two videos so that's the limbic system now don't worry we are almost done with the video we're down to our last two brain structures but before we get there if you're finding value in this video don't forget to hit the subscribe button and drop a like on the video it's free and it lets me know that you want more content okay so first we have the nucleus accumbens this is located in the forebrain near the limbic system it's associated with drug dependency as its function is in the pleasure and reward circuit and motivation and last but certainly not least we have the basal ganglia these neuron cell bodies are involved in intentional body movement they link the thalamus with the motor cortex so the information that is sent from the motor cortex gets modified by the basal ganglia damage to this area leads to parkinson's cerebral palsy and huntington's disease the basal ganglia are located in the midbrain and also the forebrain now believe it or not this was actually just a quick overview of the brain there's a lot more complexities to the brain and more structures that we could get into but for now we need to practice what we just learned answer the questions on the screen and check your answers in the comments section below and when you're down there checking your answers don't forget to go to the description of this video and check out my ultimate review packet the packet has information on every single unit of ap psychology i also have more practice sheets for the brain the neuron the endocrine system the nervous system and also all the other units there's topic review videos practice quizzes answer keys and much more it's a great resource that'll help you get an a in your class and also a five on the national exam plus there's also the discord server there where you can study with thousands of students around the world and of course don't forget that subscribe button so you don't miss out on any future mr sin content thank you guys so much for watching i'm mr sin and until next time i'll see you online [Music] you