Epilepsy Awareness Program - Brain
Human Brain is truly an amazing organ.
This article will give you an overview of the Human amazing organ called "Brain". we will examine its structure's and what each one does.
How do you remember the way to your friend's house? Why do your eyes blink without you ever thinking about it? Where do dreams come from? Your brain is in charge of these things and a lot more. The human brain is unique. It gives us the power to think, plan, speak, imagine...
The adult human brain weighs on average about 1.5 kg with a size of around 1130 cm3 in women and 1260 cm3 in men, The brain is very soft,Despite being referred to as "grey matter", the live cortex is pinkish-beige in color and slightly off-white in the interior. The brain's nerve cells are known as neurons, which make up the organ's so-called "gray matter."
At the age of 20, a man has around 176,000 km and a woman, about 149,000 km of myelinated axons in their brain. It is, nevertheless, one of the body's biggest organs, consisting of some 100 billion nerve cells that not only put together thoughts and highly coordinated physical actions but regulate our unconscious body processes, such as digestion and breathing.
The brain performs an incredible number of tasks:It controls body temperature, blood pressure, heart rate and breathing. It accepts a flood of information about the world around you from your various senses (seeing, hearing, smelling, tasting, touching, etc). It handles physical motion when walking, talking, standing or sitting. It lets you think, dream, reason and experience emotions.
All of these tasks are coordinated, controlled and regulated by your brain.
Your brain, spinal cord and peripheral nerves make up a complex, integrated information-processing and control system. The brain monitors and regulates the body's actions and reactions. It continuously receives sensory information, and rapidly analyzes this data and then responds, controlling bodily actions and functions.
Property and used with permission of Stanford Health Library
Inside the Human Brain
The brain has many parts, each of which is responsible for particular functions. The following section describes a few key structures and what they do.
The Main Players:
Front view of the Brain
Two cerebral hemispheres account for 85 percent of the brain’s weight. The billions of neurons in the two hemispheres are connected by thick bundles of nerve cell fibers called the cerebral hemispheres. Scientists now think that the two hemispheres differ not so much in what they do (the “logical versus artistic” notion), but in how they process information. The left hemisphere appears to focus on details (such as recognizing a particular face in a crowd). The right hemisphere focuses on broad background (such as understanding the relative position of objects in a space). The cerebral hemispheres have an outer layer called the cerebral cortex. This is where the brain processes sensory information received from the outside world, controls voluntary movement, and regulates cognitive functions, such as thinking, learning, speaking, remembering, and making decisions. The hemispheres have four lobes, each of which has different roles:
The frontal lobe, which is in the front of the brain, controls “executive function” activities like thinking, organizing, planning, and problem solving, as well as memory, attention, and movement.
The parietal lobe, which sits behind the frontal lobe, deals with the perception and integration of stimuli from the senses.
The occipital lobe, which is at the back of the brain, is concerned with vision.
- The temporal lobe, which runs along the side of the brain under the frontal and parietal lobes, deals with the senses of smell, taste, and sound, and the formation and storage of memories.
Property and used with permission of Nucleus Medical Media
The cerebellum sits above the brain stem and beneath the occipital lobe. It takes up a little more than 10 percent of the brain. This part of the brain plays roles in balance and coordination. The cerebellum has two hemispheres, which receive information from the eyes, ears, and muscles and joints about the body’s movements and position. Once the cerebellum processes that information, it sends instructions to the body through the rest of the brain and spinal cord. The cerebellum’s work allows us to move smoothly, maintain our balance, and turn around without even thinking about it. It also is involved with motor learning and remembering how to do things like drive a car or write your name.
The brain stem sits at the base of the brain. It connects the spinal cord with the rest of the brain. Even though it is the smallest of the three main players, its functions are crucial to survival. The brain stem controls the functions that happen automatically to keep us alive—our heart rate, blood pressure, and breathing. It also relays information between the brain and the spinal cord, which then sends out messages to the muscles, skin, and other organs. Sleep and dreaming are also controlled by the brain stem.
Other Crucial parts
Several other essential parts of the brain lie deep inside the cerebral hemispheres in a network of structures called the limbic system. The limbic system links the brain stem with the higher reasoning elements of the cerebral cortex. It plays a key role in developing and carrying out instinctive behaviors and emotions and also is important in perceiving smells and linking them with memory, emotion, and instinctive behaviors. The limbic system includes:
The amygdala, an almond-shaped structure involved in processing and remembering strong emotions such as fear. It is located in the temporal lobe just in front of the hippocampus.
The hippocampus, which is buried in the temporal lobe, is important for learning and short-term memory. This part of the brain is thought to be the site where short-term memories are converted into long-term memories for storage in other brain areas.
The thalamus, located at the top of the brain stem, receives sensory and limbic information, processes it, and then sends it to the cerebral cortex.
The hypothalamus, a structure under the thalamus, monitors activities such as body temperature and food intake. It issues instructions to correct any imbalances. The hypothalamus also controls the body’s internal clock.
list of major structures of the brain and some of their functions:
Involved in cognition and voluntary movement
Diseases related to damages of this area are Parkinson's and Huntington's
Relays information between the peripheral nerves and spinal cord to the upper parts of the brain
Consists of the midbrain, medulla oblongata, and the pons
Central Sulcus (Fissure of Rolando):
Deep grove that separates the parietal and frontal lobes
Controls movement coordination
Maintains balance and equilibrium
Outer portion (1.5mm to 5mm) of the cerebrum
Receives and processes sensory information
Divided into cerebral cortex lobes
Cerebral Cortex Lobes:
Frontal Lobes -involved with decision-making, problem solving, and planning
Occipital Lobes-involved with vision and color recognition
Parietal Lobes - receives and processes sensory information
Temporal Lobes - involved with emotional responses, memory, and speech
Largest portion of the brain
Consists of folded bulges called gyri that create deep furrows
Thick band of fibers that connects the left and right brain hemispheres
Twelve pairs of nerves that originate in the brain, exit the skull, and lead to the head, neck and torso
Fissure of Sylvius (Lateral Sulcus):
Deep grove that separates the parietal and temporal lobes
Limbic System Structures:
Amygdala - involved in emotional responses, hormonal secretions, and memory
Cingulate Gyrus - a fold in the brain involved with sensory input concerning emotions and the regulation of aggressive behavior
Fornix - an arching, fibrous band of nerve fibers that connect the hippocampus to the hypothalamus
Hippocampus - sends memories out to the appropriate part of the cerebral hemisphere for long-term storage and retrievs them when necessary
Hypothalamus - directs a multitude of important functions such as body temperature, hunger, and homeostasis
Olfactory Cortex - receives sensory information from the olfactory bulb and is involved in the identification of odors
Thalamus - mass of grey matter cells that relay sensory signals to and from the spinal cord and the cerebrum
Lower part of the brainstem that helps to control autonomic functions
Membranes that cover and protect the brain and spinal cord
Bulb-shaped end of the olfactory lobe
Involved in the sense of smell
Endocrine gland involved in biological rhythms
Secretes the hormone melatonin
Endocrine gland involved in homeostasis
Regulates other endocrine glands
Relays sensory information between the cerebrum and cerebellum
Nerve fibers located inside the brainstem
Regulates awareness and sleep
Helps to control voluntary movement and regualtes mood
The dorsal region of the mesencephalon (mid brain)
The ventral region of the mesencephalon (mid brain)
Ventricular System - connecting system of internal brain cavities filled with cerebrospinal fluid:
Aqueduct of Sylvius - canal that is located between the third ventricle and the fourth ventricle
Choroid Plexus - produces cerebrospinal fluid
Fourth Ventricle - canal that runs between the pons, medulla oblongata, and the cerebellum
Lateral Ventricle - largest of the ventricles and located in both brain hemispheres
Third Ventricle - provides a pathway for cerebrospinal fluid to flow
Region of the brain where spoken language is understood
The Brain’s Vital Statistics:
Adult weight: about 3 pounds
Adult size: a medium cauliflower
Number of neurons: 100 billion
Number of synapses: (the gaps between neurons) about 100 trillion
Number of capillaries: (tiny blood vessels) about 400 billion
See Also: Epilepsy Health Corner
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