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Human Brain Anatomy · Acedra
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An average adult human brain is about the size of a medium, cauliflower measuring roughly 15 centimeters or six inches in length. It typically weighs approximate 1.3 to 1.4 kilograms. It is surrounded and protected by cerebrospinal fluid, which cushions the brain and helps to remove waste. Here is a brief overview of all parts of the brain. We will discuss every part in more detail later in the video. Cerebrum responsible for higher cognitive functions.
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Cerebellum coordinates, motor movements, balance and posture. Brainstem controls. Heart rate. Breathing. Digestion, and sleeping. Thalamus acts as a relay center, directing sensory and motor signals to the appropriate parts of the cerebral cortex. Hypothesis. Ms.. Regulates hunger, thirst, body temperature and the release of hormones. Limbic system contains structures like the amygdala and hippocampus, and is responsible for emotions, memories and certain aspects of behavior.
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Pituitary gland releases hormones that regulate several physiological processes, including growth and metabolism. Basal ganglia is a group of nuclei that play key roles in movement regulation and habit formation and certain aspects of cognition and emotion. Corpus callosum facilitates communication between the left and right sides of the brain. Ventricles produce and circulates cerebrospinal fluid to cushion the brain and remove waste. Now we will discuss all these parts in a bit
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more detail to understand what are these and how they work. Cerebrum. The cerebrum is the largest part of the human brain, accounting for approximately 85% of its weight. It is responsible for most high order cognitive functions and can be described in further detail as follows. One hemisphere. The cerebrum is divided into two symmetrical halves known as the left and right hemispheres. These two halves are separated by a deep groove called the Longitudinal Fissure,
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but are connected by a thick band of nerve fibers known as the corpus callosum. Left hemisphere is typically associated with logical thinking, analytical, processing and language. In most right handed individuals, the left hemisphere is dominant for language. Right hemisphere is more involved with creativity, spatial ability, artistic and musical skills. It also plays a role in interpreting visual information and processing emotions. Lobes of the cerebrum, the cerebral cortex,
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the outer layer of the cerebrum is divided into four main lobes. Frontal lobe. Parietal lobe. Temporal lobe. Occipital lobe. Frontal lobe, located at the front of the brain. It's responsible for executive functions such as reasoning, decision making, planning and problem solving. It also oversees voluntary movement, speech production and aspects of personality and behavior. Parietal lobe positioned behind the frontal lobe and above the temporal lobe. It processes sensory information
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from the body, such as touch, taste and spatial positioning. The somatosensory cortex, which maps tactile information from the body, is located in this low temporal lobe found on the sides of the brain near the years. It's associated with processing auditory information, understanding language, and the formation of long term memories. It also has roles in recognizing faces and processing emotional responses. Occipital lobe located at the back of the brain. It's primarily responsible for vision.
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This includes processing visual information from the eyes, interpreting colors and recognizing shapes and movement. Gyri and sulky. The surface of the cerebrum is highly convoluted, consisting of ridges, gyri and grooves sockeye. These convolutions increase the surface area of the cerebrum, allowing more neurons to fit in and enhancing cognitive abilities. Cerebral cortex. This is the outermost layer of the cerebrum and is composed of gray matter.
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It is densely packed with nerve cells and is responsible for higher cognitive functions, including thinking, perceiving, producing and understanding language. The thickness and structure of the cerebral cortex can vary across individuals and has been associated with various cognitive abilities and personality traits. White matter located beneath the cerebral cortex, white matter is made up of myelinated or insulated axons, which are nerve fibers
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that connect different parts of the brain to each other. The myelin gives this region its white appearance and helps accelerate the transmission of signals between neurons. Basal ganglia, though often considered separately, the basal ganglia are a group of nuclei deep within the cerebrum. They play a crucial role in movement regulation, habit formation, and certain aspects of cognition and emotion. Limbic system also nested within the cerebrum. This system comprises the amygdala, hippocampus
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and other structures vital for emotion, behavior and long term memory. The cerebrum, with its intricate structures and networks, is central to human consciousness, enabling us to think, learn, create and experience emotions. It remains a focal point in neuroscience research as we strive to unravel the mysteries of human cognition and behavior. Cerebellum. The cerebellum often referred to as the little brain due to its appearance
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and size relative to the cerebellum, is an essential structure located underneath the occipital lobe of the cerebrum at the back of the brain. Here's a detailed breakdown of cerebellum, structure and functions. The cerebellum is divided into two hemispheres, similar to the cerebrum, and has a finely convoluted surface which helps maximize its surface area. These convolutions are made up of folds known as Folia. In the middle, a narrow worm like structure
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called the firmest connects the two hemispheres. The cerebellum plays a key role in fine tuning motor activities, while the cerebrum might initiate a movement. The cerebellum makes adjustments to ensure the movement is smooth and precise. It helps maintain balance in proper posture, particularly when the body is in motion. The cerebellum is essential for tasks that require practice and repetition, such as riding a bicycle or playing a musical instrument.
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More recent research has revealed the cerebellum involvement in certain cognitive and emotional functions. This includes processes like attention, language and regulating fear and pleasure, responses, layers. The cerebellar cortex, which is the outer layer of the cerebellum, is made up of three distinct layers a molecular layer, the outermost layer containing few neurons, but many extensions from other cells. Perkins layer contains Perkins cells, large neurons that send inhibitory projections
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to the deep cerebellar nuclei, granular layer, the innermost layer made up of tiny granule cells that send excitatory projections up to the molecular layer. Deep cerebellar nuclei embedded within the cerebellum are clusters of gray matter known as the deep cerebellar nuclei. These serve as the primary output canters of the cerebellum, communicating its processed information to other brain regions peduncle.
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The cerebellum communicates with other parts of the brain via three paired structures known as peduncle. Superior cerebellar peduncle connects the cerebellum to the midbrain and thalamus, primarily carrying output from the cerebellum to other brain regions. Middle cerebellar peduncle connects the cerebellum to the Pons, and is the primary input route to the cerebellum. Inferior cerebellar peduncle connects the cerebellum to the medulla oblongata, facilitating
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both input and output between the cerebellum and other brain regions. Despite cerebellum, smaller size compared to the cerebrum, the cerebellum contains more neurons and plays a crucial role in a variety of tasks, ensuring they are executed with precision and grace. Brain STEM. The brain stem is located at the base of the brain. It serves as the bridge connecting the cerebrum and cerebellum to the spinal cord. The brainstem is critical for basic life functions,
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such as breathing, heart rate and blood pressure. It's involved in reflexes, including those that regulate balance and hearing. It plays a role in regulating the sleep wake cycle. The brainstem serves as a conduit with ascending tracks, transmitting sensory information to the brain in descending tracks, sending motor information to the body. Cranial nerves three through 12 originate from the brainstem, controlling functions such as facial expressions, swallowing and sensation in the face.
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Here's a detailed look at brainstem components. The brainstem can be divided into three main structures, each with specific features and functions. Midbrain or Ms. encephalopathy. The most superior portion of the brain stem. The midbrain is located beneath the thalamus and above the pons. Prominent structures include the cerebral peduncle, which contain motor and sensory tracts. And the corporate control Gemini, composed of the superior and inferior Caligula.
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The superior Caligula are involved in visual reflexes, while the inferior Caligula are associated with auditory processing. The midbrain houses, the red nucleus involved in motor coordination, and the substantia nigra, which plays a role in reward and movement. The midbrain contains nuclei for cranial nerves. Three and four. Pons positioned between the medulla and the midbrain, the pons appears as a bulging region on the anterior part of the brain stem.
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It primarily acts as a relay station transmitting information between the cerebrum, cerebellum and spinal cord. The Pons also plays a role in regulating the sleep wake cycle and houses nuclei for cranial nerves five through eight. Medulla oblongata located closest to the spinal cord. The medulla oblongata is the most inferior part of the brainstem. It regulates several vital and involuntary functions such as heartbeat, blood pressure and respiration.
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Any significant damage to this region can be life threatening. It also contains the pyramids, which are too elongated ridges on its interior surface, where motor fibers cross over, or because eight. This decoration is why each hemisphere of the brain controls the opposite side of the body. The medulla also houses nuclei for cranial nerves eight through 12. Reticular formation spanning the length of the brainstem. The reticular formation is a network of interconnected neurons.
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It's vital for consciousness, sleep, regulation and overall alertness. Damage to this area can result in coma. The reticular formation can also filter sensory input to decide what information is relayed to the cerebral cortex. Thalamus. The thalamus is located in the center of the brain, just above the brainstem and is nestled between the cerebral cortex and the midbrain. Each hemisphere of the brain contains a thalamus. It is composed of two symmetrical, egg shaped masses of gray matter.
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And these are surrounded by a thin layer of white matter called the external medullary lamina. It performs various functions. Relay station. One of the primary roles of the thalamus is to relay sensory information from peripheral receptors in the spinal cord to the appropriate regions of the cerebral cortex. It processes and transmits inputs from all the senses except smell to associated cortical areas. Motor functions. The thalamus also receives information from the cerebellum and basal ganglia
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and relays it to the motor areas of the cerebral cortex, aiding in the coordination and modulation of movement, sleep and wakefulness. It's involved in regulating states of sleep and wakefulness. The thalamus plays a role in controlling the sleep spindle activity during the sleep cycle. Consciousness. The thalamus contributes to consciousness and alertness, particularly through its connections with the cerebral cortex and the reticular formation in the brainstem. Pain perception.
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The thalamus is also involved in processing pain signals and can modulate the perception of pain. Hypothalamus. The hypothalamus is a small but crucial region of the brain that plays an integral role in connecting the nervous system to the endocrine system via the pituitary gland. The hypothalamus is located below the thalamus, approximately above the pituitary gland, and forms the lower walls and floor of the third ventricle in the brain.
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It's about the size of an almond and consists of various nuclei and nerve fibers. The hypothalamus is connected to many parts of the central nervous system, including the cerebral cortex, thalamus, basal ganglia and limbic system. The pituitary gland is attached to the hypothalamus by the infant fibula or pituitary stock. Through this connection, the hypothalamus can regulate a wide variety of bodily functions by influencing hormone release from the pituitary hypothalamus.
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Perform various functions, for example, endocrine system regulation, autonomic nervous system regulation, temperature regulation, hunger and thirst, regulation, sleep wake cycles and circadian rhythms, emotion and behavior and memory. Limbic System. The limbic system is a collection of structures in the brain involved in various functions, including emotion, behavior, motivation, long term memory and olfaction. Limbic system is a group of interconnected structures.
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Here are some of the primary components. Amygdala, a small almond shaped set of neurons located deep within the brain's medial temporal lobe. It's key in processing emotions, especially those related to fear and pleasure. Hippocampus. Located in the medial temporal lobe. The hippocampus plays a critical role in forming new memories and connecting emotions in senses such as smell and sound to memories. Thalamus, while primarily a relay station for sensory and motor signals
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to the cerebral cortex, the thalamus does have connections with the limbic system and is involved in some of its functions, especially in relaying sensory information. Hypothalamus is situated beneath the thalamus. The hypothalamus regulates vital functions like hunger, thirst, body temperature and sleep. It also helps in controlling mood and emotions and is integrally linked to the endocrine system cingulate gyrus, an arc shaped region that plays a role in regulating
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aggressive behavior and linking behavioral outcomes to motivation. Para hippocampal gyrus surrounding the hippocampus. This region plays a role in memory encoding and retrieval. Basal ganglia, while often associated with movement, the basal ganglia have connections to the limbic system and play a role in certain emotional and cognitive functions. Olfactory bulbs. These are involved in the sense of smell which can evoke strong emotional responses and memories. Pituitary gland.
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The pituitary gland, often termed the master gland, is a small, pea sized structure that plays a crucial role in the human endocrine system. The pituitary gland is situated at the base of the brain right below the hypothalamus and is housed within a bony structure called the skeleton of this finite bone. It is attached to the hypothalamus by a thin stalk known as the infant fibula or pituitary stock. The gland is divided into two primary sections the anterior pituitary
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or adeno hypothesis and the posterior pituitary or neuro hypothesis anterior pituitary adeno hypothesis. This lobe synthesizes and releases several hormones regulated by releasing and inhibiting hormones sent from the hypothalamus via the portal blood system. Hormones produced and released by the anterior pituitary include growth hormone, thyroid stimulating hormone, adrenal cortical tropic hormone follicle stimulating hormone, luteinizing, hormone prolactin endorphins
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and then cephalopods posterior pituitary. Neuro hypothesis. Unlike the anterior pituitary which produces hormones, the posterior pituitary stores and releases hormones produced by the hypothalamus. Hormones released by the posterior pituitary include oxytocin and vasopressin. Basal ganglia. The basal ganglia are a group of nuclei located deep within the cerebral hemispheres that play crucial roles in a range of functions, including the control of voluntary motor movements, procedural learning,
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habit formation and emotion, among others. The basal ganglia are composed of several interconnected nuclei, which includes striatum globus pavlidis sub thalamic nucleus and substantia nigra. The basal ganglia have several pathways that process and relay information, direct pathway, indirect pathway, hyper direct pathway. Proper balance between these pathways is crucial for smooth motor control function. Basal ganglia perform several functions which include motor control
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the basal ganglia in coordination with the cerebral cortex, thalamus and brainstem help smooth out and coordinate movements. They are involved in the initiation and termination of movements, ensuring movements are fluid and purposeful. Procedural learning. They play a role in the learning of routines or sequences, especially motor sequences, emotions and behavior. The basal ganglia are connected to the limbic system and have been implicated in the control of emotional behaviors and responses.
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Cognitive functions. They contribute to certain aspects of cognitive processing, decision making and task switching. Corpus callosum. The corpus callosum is the largest bundle of nerve fibers in the brain that connects the left and right hemispheres, allowing them to communicate and coordinate with one another. Anatomy and structure. The corpus callosum lies beneath the cerebral cortex, arching around the lateral ventricles. It is composed of over 200 million axonal projections,
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facilitating the transfer of information integration of motor sensory and cognitive performances between the cerebral hemispheres. The corpus callosum can be segmented into different regions based on its anterior to posterior orientation, rostrum, general body or trunk, and selenium functions. Corpus callosum performs several functions which include inter hemispheric communication. Its primary role is to integrate motor sensory and cognitive information between the two hemispheres.
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For instance, sensory information received in one hemisphere can be shared with the opposite hemisphere to produce coordinated motor outputs to facilitate learning. It's believed to play a role in the sharing of learning and memory processes between hemispheres. Redundancy and recovery in cases of cerebral damage like a stroke to one hemisphere, the corpus callosum may facilitate compensation by transferring functions to undamaged areas in the opposite hemisphere.
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Ventricles The ventricles of the brain are a connected system of cavities filled with cerebrospinal fluid CSF. These cavities not only serve as a reservoir for CSF, but also play a role in its circulation and in cushioning the brain. Anatomy and Structure. The ventricular system comprises four main ventricles lateral ventricles, first and second ventricles. These are the largest of the ventricles and are found within each hemisphere of the cerebral cortex.
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Having a curved horseshoe like shape, each lateral ventricle consists of a central body and three protruding horns. The anterior or frontal posterior or occipital and inferior or temporal horns. Third ventricle. This is a narrow funnel shaped cavity located in the midline between the left and right. Thalamus. It's connected to each lateral ventricle by the inter ventricular foramen or foramen of manuel fourth ventricle located between the pons and the cerebellum.
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It communicates with the third ventricle above through the cerebral aqueduct or aqueduct of Sylvia's function. Cerebral spinal fluid or CSF production. The ventricles are lined by a pen themselves, and within the ventricles specialized structures called choroid plexus is produced. CSF. Brain protection. CSF acts as a cushion, providing a protective layer for the brain against trauma. The fluid also helps maintain intracranial pressure, which is crucial for normal brain function,
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nutrient and waste transport. CSF facilitates the exchange of nutrients and waste products between the brain and the blood. This was the basic overview of human brain, its components and functions. Which brain and its components perform. We will go in more detail in some other video. That's it for today. Hope you like this video. For more videos on human body and organ system, please subscribe to this channel. See you in the next video.
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