Traumatic brain injury (TBI) involves an unpredictable and wide array of neurological structures. The most basic levels of cognition relate to how information enters the central nervous system (CNS) and is gathered, moved, reduced, used, and stored. Information flow throughout the CNS is a primary concern for cognitive function. Tactile sensory pathways include those responsible for pain and temperature, those responsible for conscious proprioception and discriminative touch, and those responsible for unconscious proprioception. Visual stimuli enter the system at a supratentorial level, coursing from the retina via the optic nerve to the lateral geniculate nucleus of the thalamus. A primary function of the hypothalamus is regulation of the autonomic nervous system. Growth hormone deficiency (GHD), hypogonadism, and hypothyroidism are the most common sequelae of pituitary injury. Thyroid function is crucial for normal brain development and for proper production of oligodendrocytes. The medial temporal lobe (MTL) includes the hippocampal region, entorhinal, perirhinal, and parahippocampal cortices.