The cerebrum is the largest part of the brain and is responsible for the higher levels of thinking. The gyri are the folds of the brain (cerebrum) and the sulci are the grooves between the gyri. The cerebellum is the little brain and is responsible for balance and coordination.

The diencephalon is the region of the brain between the cerebrum and the brain stem; it contains the epithalamus, thalamus, hypothalamus, ventral thalamus, and the third ventricle. The corpus callosum is the structure that connects right and left cerebral hemispheres. The pituitary gland is the small structure in the brain that controls the endocrine system. A ventricle is a fluid filled cavity within the brain.

The nervous system consists of the central nervous system (CNS) and the peripheral nervous system (PNS). The CNS can be thought of as the body's master control unit, it consist of the spinal cord, brainstem, and brain. The PNS is the body's link to the outside world, and consists of the autonomic nervous system (which branches into the sympathetic and parasympathetic nervous system) and the somatic nervous system. 

The occipital lobe is the main area for interpreting visual stimuli. Wernicke's area is responsible for speech perception. The parietal lobe processes the sensations of touch, pressure, and temperature amongst other things. The temporal lobe processes sound mainly. Wernicke's area is located here. The olfactory lobe is involved in processing the sense of smell.

The red nucleus is part of the midbrain. The vermis is part of the cerebellum and helps regulate trunk coordination, as well as vestibulo-ocular reflexes (VORs). The flocculonodular lobes, also part of the cerebellum, and work with the vermis to maintain trunk control and also help control the VORs. The dentate nucleus is a part of the cerebellum involved in motor planning in movement of the arms and legs.

The salivatory nucleus gives rise to the nerves that innervate the submandibular and sublingual salivary glands, as well as the lacrimal and nasal glands, and is the parasympathetic motor nucleus of the facial nerve however, it is found in the dorsal pons, not the medulla. The masticator nucleus is the trigeminal nerve motor nucleus, and is found in the pons. The mesencephalic nucleus is a sensory nucleus of the trigeminal nerve, and is found in the pons. The facial motor nucleus is found in the pons, and gives rise to the facial nerve branches that innervate the muscles of facial expression.

The Edinger-Westphal nucleus is the parasympathetic nuclues of cranial nerve III, and innervates (among other structures) the pupillary constrictors and lens ciliary muscles. The inferior salivatory nucleus is the parasympathetic nucleus of cranial nerve IX, and gives rise to the nerve that innervates the parotid gland. The superior salivatory nucleus is the parasympathetic nucleus of the facial nerve, and innvervates (among other structures) the submandibular and sublingual glands. The nucleus ambiguus has no parasympathetic function and is associated with motor functions of cranial nerves IX and X.

The precentral gyrus is an important fold found in the frontal lobe and is a landmark for the primary motor area. The parietal lobe contains another important gyrus called the postcentral gyrus, which is the landmark for the somatosensory area of the cerebral cortex. The primary auditory area is located in the temporal lobe while the primary visual area is located in the occipital lobe. The insula is a structure that lies within the lateral fissure. It cannot be seen in the external view of the brain and plays a role in the limbic system. 

The postcentral gyrus, a landmark for the somatosensory area of the cerebral cortex, is located in the parietal lobe of the cerebral cortex.  The frontal lobe contains the precentral gyrus, which is a landmark for the primary motor area. The primary auditory area is located in the temporal lobe while the primary visual area is located in the occipital lobe. The insula is a fold in the cerebral cortex found within the lateral fissure. 

The brainstem consists of the midbrain, pons, and medulla oblongata. The brainstem continues inferiorly to become the spinal cord. The brainstem is responsible for basic living functions, including but not limited to: respiration, circulation (including heart rate), and digestion. As such, any injury to the brainstem would be catastrophic. Additionally ten of twelve cranial nerves pass through the brainstem, going on to provide the face and neck with motor and sensory functions. Furthermore, nerve conduction of the motor and sensory systems of the brain and body pass through the brain stem including the corticospinal tract (involved in motor activity), the posterior column-medial lemniscus pathway (involved in fine touch, vibration sensation, and proprioception), and the spinothalamic tract (involved in pain, temperature, itch, and crude touch).