The study of the constituents of the brain is the same as finding one’s way around an unknown city. Generally, one needs a system of bearings and its main divisions. Ones one has acquired this information, he/she can converse the general position of any destination with ease. To be acquainted with the fact that the human brain has 5 divisions, it is essential to comprehend its premature development. In the embryos of vertebrates, the tissues which in time develop into the CNS are known as fluid-filled tubes. The initial signs of brains development are 3 swellings that crop up at the frontal part of this tube. They finally grow to form the fore, mid and hindbrain. “Before birth, the initial swellings become five. This is because the forebrain and the hindbrains grow into two different swellings. The five swellings are the Telencephalon, the Diencephalon, the Mesencephalon, the Metencephalon, and the Myelencephalon” (Pinel, 2007). These are the ultimate divisions of the human brain. This paper will therefore focus on the human brain, its divisions and its functionality.
The CNS (Central Nervous System) is constituted into the spinal cord and the brain. The brain is the section of the CNS found within the skull. “It is commonly divided into five main parts, listed here in the order from the lowest. They are the Medulla Oblongata (Myelencephalon), Pons and Cerebellum (Metencephalon), Midbrain (Mesencephalon), Thalamus and Hypothalamus (Diencephalon) and Cerebral Hemispheres (Telencephalon)” (Seymour, 2000).
The brain of a human being is in the center of the nervous system. Surrounded by the cranium, the human brain has an identical structure as that of other animals. The major difference is that it is more than 3 times larger than the brains of typical mammals with the same body size. Most of the extension is in the cerebral cortex, this is a complex layer of neural tissues covering the exterior part of the forebrain. In particular, the frontal lobes are extended; these are connected to the executive functioning such as self-control, scheduling, and way of thinking, interpretation, and conceptual thought. The brain segment that is devoted to visualization is also significantly broadened in human beings (Johansons, 2006).
The human-brain checks and controls the body’s actions and responses. It constantly gets sensory data and does a rapid analysis on this information, and then acts in response, managing bodily actions, responses and functionality. The brainstem manages breathing, heart rate, and additional autonomic courses of action that are autonomous of the conscious brain functionality. As shown by Murre & Sturdy (2005), “the neocortex is the center of higher-order thinking, learning, and memory, while the cerebellum is responsible for the body’s balance, posture, and coordination of movement”.
The Medulla (Myelencephalon) is the brain structure/division that is most posterior. It is made up of strips ferrying signals linking the body to the brain. The reticular formation is the most interesting fraction of this structure. The reticular formation is a multifaceted system of more than 100 miniature nuclei that takes up the mid of the brain-stem as of the posterior edge of this structure to the frontal edge of the mid-brain. It has a mesh-like formation, the nuclei of this part are responsible for a variety of functionality, these include sleeping, concentration, motion, muscle-tone safeguarding, and a variety of cardiac, circulatory and respiration responses. Injury to this part of the Myelencephalon is considered to be life-threatening. In general, the Myelencephalon does not play a significant function in verbal communication or comprehension.
The Pons and Cerebellum (Metencephalon) similar to the Myelencephalon, accommodates numerous ascending and descending strips and a fraction of the reticular formation. It forms a protuberance known as Pons situated on the brainstem’s ventral surface. This is a key division of this structure while the other is the Cerebellum. The latter is a big, complex part on top of the brain-stem’s dorsal part. This is a vital sensor-motor division, cerebella injury gets rid of the aptitude to accurately manage a person’s motion while adapting them to altering conditions. This part has extra neurons and is generally responsible for motor coordination (Thompson, 2000).
On its part, the midbrain (Mesencephalon) is divided into 2 (Tectum and Teqmentum). “The Tectum is the dorsal surface of the midbrain” (Pinel, 2007). In animals, this part is made up of 2 duo bumps. The posterior (inferior colliculi), has an acoustic functionality; the frontal pair (superior colliculi) has visualization functionality.
The tegmentum, on the other hand, is the partition of the midbrain ventral to the tectum. “In addition to the reticular formation and tracts of passage, the tegmentum contains three colorful structures that are of particular interest to biopsychologists: the periaqueductal gray, the substantia nigra, and the red nucleus” (Pinel, 2007). The first structure is a grayish matter found in the cerebral-aqueduct. This is a duct linking the 3rd and 4th ventricles. This part has the function of arbitrating the pain reduction outcomes of opiate drugs. The substantia-nigra and red-nucleus are all vital constituents of the sensorimotor system.
Thalamus and Hypothalamus (Diencephalon) are double structured. The Thalamus is a big, two-lobed formation constituting the upper part of the brainstem. The lobes are situated on all sides of the 3rd ventricle. These lobes are joined together by Massa-intermedia that run in the ventricle. This part has numerous nuclei pairs that are mostly projected to the cortex. Some of these are sensory relaying which get signals from sensory-receptors, process them, and finally, send them out to the correct areas in the sensory cortex. Therefore, this part is responsible for the sensory system that relays senses to the audio and visual organisms. This is also responsible for our general attention.
The hypothalamus, on the other hand, is situated under the anterior thalamus. Its function is to regulate a number of motivated behaviors. It applies its functionality partly by regulating hormone release in the pituitary glands. The pituitary gland hangs from it on the ventral surface.
Apart from this gland, there is 2 other formation on the hypothalamus. These are the “optic chiasm and the mammillary bodies. The optic chiasm is the point at which the optic nerves from each eye come together. The mammillary bodies (pair of spherical nuclei) are located on the inferior surface of the hypothalamus behind the pituitary” (Pinel, 2007).
The Cerebral Hemispheres (Telencephalon), is the biggest part of the brain. This part arbitrates its most intricate functions. This division instigates voluntary motion, reads sensory input while arbitrating complicated cognitive developments such as studying, talking and problem resolving.
“Of the other subcortical and interior portions of the Telencephalon, the basal ganglia, which partially surround the diencephalon, participate in motor functions, including articulation of speech” (Pinel, 2007). The hippocampus and the amygdaloid nucleus, found inside the cortex’s lower parts, are very vital in expressing emotions.
The cortex is what is seen in many brain pictures. This is illustrated by the many grooves found on it. The many folds of this part are for the sole reason of making use of the small part in the skull the most. These grooves are referred to as the Sulcus. This is one of the parts dividing the cortex into its major partitions. The cortex is further divided into 4 lobes which are “the frontal, temporal, parietal and occipital lobes” (Pinel, 2007). These are what constitute the Telencephalon.
All divisions/structures of the human brain work together monitoring and regulating one’s bodily actions and responses. The human brain forever gets sensory data that it quickly analyzes after which it reacts, and in the process manages the body’s actions and functionality.
References
Johansons, D.C. (2006). The Brain. New York: Simon and Schuster.
Murre, JM., Sturdy, DP. (2005). “The connectivity of the brain: multi-level quantitative analysis”. Biological cybernetics, 73 (6), 529–45.
Pinel, J. P. J. (2007). Basics of biopsychology. Boston, MA: Allyn and Bacon.
Seymour, R. (2000). Language and Brain: Neurocognitive Linguistics. Houston: Rice University Press.
Thompson, R. (2000). The Brain: An Introduction to Neuroscience. Worth Publishers.