The brainstem is made up of the medulla and pons. Together, these make up the oldest (evolutionarily speaking) region of the brain. In cases of patients with brain damage, there have been observations made that no higher brain power is required to control heart rate and breathing because it's all managed by the medulla. The thalamus is not technically part of the brainstem, although it does attach to it via the reticular formation.

The medulla and pons make up the brainstem. As does the cerebellum, also known as "the little brain. The cerebellum is responsible for nonverbal learning, memory and balance. The amygdala is considered to be a primitive structure in the brain, tied to fear response. All these structures can be observed in primitive animals. 

Broca's area, however, is tied to language expression - a more recently evolved capability. The "old" structures of the brain are old in terms of their evolutionary development.

The amygdala is responsible for evoking fear and aggression.

The "reward centers" in the brain were observed in the 1954 study by James Olds and Peter Milner where they mistakenly placed an electrode in a rat's hypothalamus instead of the intended reticular formation. They observed the rat continuously visiting the location where it had previously received the electrode stimulation. The rat continued to return to that location for what appeared to be some perceived reward.

The hypothalamus is responsible for maintaining body temperature, regulating thirst and hunger, etc. In a sense, it's like maintaining a body's equilibrium - that is, homeostasis. In doing so, this may require the activation of the pituitary (master) gland, which will in turn release hormones.

The occipital lobe is located far in the back of the brain. It is in charge of processing visual signals.

The temporal lobes are located on the sides of the brain, close to where the ears are. They are in charge of processing auditory information.

The cerebellum is important in helping us maintain balance and coordination. It is also in charge of precise timing and other motion related activities. It is located in the back of the brain, under the occipital lobe, and near the brain stem.

The brain stem is one of the first parts of the brain to be formed during fetal development. It controls essential bodily functions such as heart rate, body temperature, and breathing. It is located at the base of the brain, near the cerebellum, and connects to the spine through a bundle of nerves.

The myelin sheath is the fatty layer that covers the axon. It helps to speed up nerve impulses and keeps them channeled on the neuron.

Varolio, a 16th-century anatomist and lecturer, was likely the first anatomist to study the brain from the bottom upwards, instead of the traditional top-down approach used by anatomists until that time. He also correctly theorized the pons as being vital in communication between the brain and spinal cord.

The hindbrain is the division of the brain containing the pons, medulla, and cerebellum, which are together largely responsible for autonomous processes of the body, such as breathing, blood pressure, heart rate, and body temperature.