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The Human brain is the most highly structured system in the known universe. It controls a plethora of bodily processes; processing sensory information; regulating biochemical processes; coordinating movement and of course, providing us the ability of higher thought/perception. There are three primary areas of the human brain:
• The hindbrain
• The midbrain
• The forebrain
Hindbrain
The rhomencephalon is made up of the brain stem and cerebellum and controls a number of of actions. It is located in the cranial cavity.
One crucial mass of tissue that makes up the hindbrain is the medulla oblongata. The medulla oblongata is directly above the spine and is so critical to life that pathogens affecting it are many times causing death.
Another structure is the cerebellum. This region is sometimes called the “little brain”. It looks different to the rest of the brain. It has a surface of densely folded gray matter. It is mainly involved with movement.
The Pons measures more or less an inch in length and lies next to the midbrain and the lower part of the brain stem (medulla oblongata). It contains nuclei that have significant involvment with sleep, respiration, swallowing, bladder control, hearing, equilibrium, taste, eye movement, facial expressions, facial sensation, and posture.
Midbrain
The mesencephalon is above the Pons and inferior to the cerebral hemispheres. The rear part of the mesencephalon is known as the tectum, it is involved in reflexes in relation to auditory processes and visual processes (e.g. the eye movement, pupil size, lens shape). The ventral portion of the midbrain is called the tegmentum, it is mainly a highly structured association of neurones accountable for unconscious homeostatic and reflexive pathways.
Forebrain
The Forebrain is superior to both the rhombencephalon and the midbrain as well as being the most anterior. It has important roles in the following processes:
 Mastication
 Directs sensory impulses through the body
 Equilibrium
 Vision
 Eye movement
 Facial sensation
 Hearing
 Phonation
 Intelligence
 Memory
 Personality
 Respiration
 Salivation
 Swallowing
 Smell
 Taste
The rhombencephalon is split into 2 essential structures:
 Telencephalon
The neocortex is the folded outer portion of the brain, in humans it is between 2-4mm thick. It has the highest levels of non- insulated grey matter of any structure of the brain. The cortex forms folded protrusions (thus significantly increasing the structure without expanding the volume) called gyri; so much so that more than 2/3 of the brain lie in these folds (known as sucli).
The Frontal lobe is the most ventral region of the lobes and is additionally superior to the temporal lobe. This region of the brain is interconnected with many of the the most important traits associated with personality (e.g ability to figure-out future results of action taken), learning, impulse control, and prioritising actions. It is host to most of the brain’s dopamine receptors (these are the central feedback through which learning is rewarded).
The temporal lobes are inferior to the frontal and parietal lobe and anterior to the occipital lobe. Research imply they are the central structure of the brain involved in declarative memory; damage to the temporal lobes can result in an incapability to form memory after the point of damage (anterograde amnesia). They contain the hippocampus (long-term memory) and are involved in auditory and higher visual perception (e.g. facial recognition).
The parietal lobe is anterior of the occipital lobe, posterior of the frontal lobe and superior of the temporal lobes. The border between the frontal lobe and the parietal lobe is marked by the central sulcus. The border between the occipital lobe and the parietal lobe is marked by the parieto-occipito sulcus and the border between the temporal lobe and the parietal lobe is marked by the lateral sulcus. The parietal lobe coordinates information from multiple senses in order to establish spatial orientation.
The Occipital lobe is the most posterior of all the main lobes of the brain. Anatomically this structure contains most of the visual cortex (Brodmann area 17) and damage to the occipital lobes results in vital homonomous vision loss (i.e. the effect is the same in both eyes). The occipital lobes are where shape, colour, and like the temporal lobes, facial recognition take place. Projections from the occipital lobe to the superior temporal-parietal section are vital for perceiving motion of objects.
The basal ganglia are a section of the corpus striatum and are in essentially a set of interconnected nuclei within the brain. Information from the cerebral cortex passes to the basal ganglia where it is processed and then relayed back via the thalamus. There are a plethora of connections and pathways within and although the basal ganglia have long been implicated in motor function; it is known this is not there sole function, though the exact process in relation to behaviour control have yet to be properly established. Evidence suggests that during learning, basal ganglia and medial temporal lobe memory systems are activated simultaneously and that in some learning situations competitive interference exists between these two systems. One theory suggests the basal ganglia decides which out of a number of possible actions the cortex may be planning, actually gets executed. Fitting this with idea that dopamine is used as a reward system for learning.
