Brain, being the central command organ in our body, is the main sensory organ which controls our movement, emotions, reactions to the surrounding and makes us humans. Thanks to the brain, we have the command of our body and we are able to communicate. It is included in every second of our lives, from the breathing to the creation of the memory and movement. It interprets the information and creates the action. It weighs about 3 pounds and it is connected to the periphery via the spinal cord and it contains about 86 billion nerve cells called neurons which are gray matter.
The central nervous system has its regulation via chemical neurotransmitters which are being secreted at the end of axons which are the ends of neurons. It is always in the state of homeostasis and it balances the action of our 5 senses: taste, smell, sight, touch and hearing and our actions in a form of speech, movement, thinking, memory, function of our internal organs.
The brain has a few main structures divided into Cerebrum, Cerebellum, Limbic System and Brainstem.
The largest part of the brain is the cerebrum. It is divided into 4 parts: the frontal lobe, the parietal lobe, the occipital lobe and the temporal lobe. These 4 lobes build cerebral cortex. It also has two hemispheres where they are connected via axons, which are the nerve fibers which transfer the information.
The frontal lobe is the part of the cerebrum which controls behavior, emotions, personality, smell, planning, problem-solving, judgment, parts of speech, body movement via coordinated movements (motor strip), attention, self-awareness, concentration and intelligence.
The parietal lobe is associated with orientation, recognition, movement, perception of stimuli such as internal stimuli, tactile sensation, and visual stimuli. It is in charge of reading, language and it has a motor and sensory cortex.
The sensory cortex is the part of the brain which receives the stimuli from the peripheral part of the nervous system such as spinal cord and further, such as the extremities movement and other body parts. It is in the front portion of the parietal lobe and it extends to the middle part which receives the information of the tactile stimuli, pain, and pressure.
The motor cortex is at the top middle part of the brain and parietal lobe. It controls the body movement and monitors the brain activity.
The temporal lobe controls the memory, hearing, sequencing and organization and understanding language using Wernicke’s area. It creates memories using visual and auditory senses. Wernicke’s area is the part which is in charge for auditory cortex. It helps us understand the language. Its function isn’t still fully known.
This part of the cortex is in charge of receiving the visual stimuli. It is located at the back of the head at the bottom. It has Broca’s area which is also in charge of understanding the spoken word and language. It controls the facial neurons and it has the inferior frontal gyrus section which is triangular and opercular section.
The “little brain” is the part of the brain that controls the balance, coordination, posture. Since its function, our movement would be rigid and we wouldn’t be able to do any fine movements.
The limbic system is responsible for controlling our emotions. It is also called “emotional brain” and it contains hypothalamus, thalamus, amygdala, and hippocampus.
The amygdala is the part of the limbic system which carries the memories, fears, and emotions. It is located in the temporal lobe and it takes a large portion of the telencephalon. It is linked to pleasure and some of the conditions such as depression, anxiety, post-traumatic stress disorder can be associated with abnormal functions of the amygdala.
The hypothalamus controls the involuntary actions such as temperature, hunger, mood, thirst. It is also included in the hormonal circle where it secretes the release hormones which affect pituitary gland and the rest downwards.
Hippocampus is associated with learning, creating permanent memories from the short-term memory. It is also in charge of accurate movements. It is located in the cerebral hemisphere and it allows us to recall the spatial relationship with the surrounding.
The thalamus helps with the attention, pain and it monitors the pain. It basically, senses the stimuli that body experiences and it helps with controlling it. Monitoring occurs at the center of the brain.
The structure which is responsible for the involuntary actions such as heartbeats, blood pressure, breathing is brain stem. It is the simplest part of the brain and it is made out of three parts: midbrain, pons, and medulla.
Midbrain or as we call it mesencephalon is the part which helps the hearing, body movement, and vision. It is made out of two parts: tegmentum and tectum. It allows the voluntary motor function via axon impulses which are being sent down the brain stem.
The part of the brain called pons is located in the hindbrain, between the medulla oblongata located below and in front of the cerebellum. It carries the signals from the brain to the cerebellum, medulla, and thalamus. It controls sleep cycle, respiration, hearing, taste, eye movement, expression, the sensation of the face, posture, swallowing, bladder control, equilibrium.
The medulla oblongata is the part which controls the heart beat and the breathing. It is also located in the hindbrain, in front of the cerebellum. It controls the sneezing and vomiting as well. Since it controls the ventilation, sympathetic and parasympathetic nervous system, vasomotor centers and reflexes, it is an important part of the brain.
- The brain is very sensitive to the oxygen level, where the lack of oxygen from 5 to 10 minutes can cause permanent brain damage.
- Believe it or not, your brain is still developing even in the later stages of life, till your late 40s.
- Although smaller than the rest of the body, it uses 20%of oxygen from the blood stream.
- When we are awake, our brain produces the electricity enough to light a small bulb.