The Five Major Structure of the Brain
The brain is composed up of roughly 77 to 78% of water, 10 to 12% lipids, 8% proteins, 1% carbs, 2% soluble organics, and 1% inorganic salt. The brain can actually grow as it obtains more knowledge. The brain is made up of the five major structures: the myelencephalon, metencephalon (the hindbrain), mesencephalon (the midbrain), diencephalon, and the telencephalon (the forebrain). The myelencephalon is a structure of the medulla oblongata. The medulla transmits signals between the spinal cord and the upper areas of the brain. It is the lowest area of the brainstem. This area of the brain carries signals between the body and the brain.
The functions of the myelencephalon include autonomic functions, breathing, digestion, heart rate, swallowing, and sneezing. The mentencephalon is located under the rear area of the cerebrum and above the medulla oblongata. This structure is made up of the cerebellum and pons (the connection to the cerebellum). The functions of the metencephalon include arousal, balance, cardiac reflexes, muscle movement and maintenance, and sleep. Along with the myelencephalon, they represent the hindbrain. The mesencephalon is the midbrain structure of the brain stem. It is what bridges the hindbrain to the forebrain. The functions of he mesencephalon include controlling sight response, eye movement, pupil dilation, body movement, and hearing. Within the mesencephalon is the tectum, which controls visual and auditory responses. The tegmentum is another part of it, which controls awareness, attention, and motor functions. The telencephalon is at the front of the brain and is made up of the basil ganglia, the cerebral cortex, the olfactory bulb, and the corpus striatum. The functions of the telencephalon include: determining intelligence, personality, sense of smell, sense of touch, sensory impulse interpretations, organization and planning.
The diencephalon is located in between the cerebral hemispheres and is greater than the midbrain. It is composed of the thalamus and hypothalamus structures. The thalamus acts as a relay point for nerve impulses that are inbound from around the body that are then dispatched to the appropriate area of the brain for processing. The hypothalamus controls hormone secretions produced from the pituitary gland. These hormones control growth and instinctual behaviors such as eating, drinking, sex, anger, and reproduction. The hypothalamus also controls when a new mother begins to lactate.
Some of the functions of the diencephalon include: sensing impulses moving throughout the body, controlling autonomic functions, endocrine functions, motor functions, homeostasis and basic senses such as hearing, vision, smell, and taste. The cerebrum is the bigger portion of the brain and it consists of 85% of the overall weight of the brain. It has a unique outer surface with deep wrinkles, which is the cerebral cortex that consists of “gray matter”. The cerebrum is what makes the human brain as powerful as it is. Unlike animals that have larger brains such as elephants, dolphins, and whales, we have the most developed cerebrum.
It’s high development is due the fact that it’s compressed very tightly in our skulls, covering the remainder of the brain and the deep folds aid in maximizing the surface area of the cortex. The cerebrum is composed of two hemispheres, which consist of four lobes or regions. The frontal lobes are located behind the forehead and are involved with speech, thought, emotion, learning, and movement functions. The parietal lobes process sensory information such as temperature, touch and pain. They are located behind the frontal lobes. The occipital lobes are involved with vision and are located in the back of the brain.
Last but not least, there are the temporal lobes, which are involved with hearing and memory. They are located near the temples. The next biggest portion of the brain is the cerebellum, which sits below the back end of the cerebrum. It coordinates our muscle movement and keeps our balanced controlled. It consists of both grey and white matter, and is what transmits signals and messages to the spinal cord and other parts of the brain. As the preceding paragraphs show, the human brain is an incredible and complex organ. However it is a highly sensitive and delicate organ, and requires great protection.