2. Anatomy

• Central nervous system (CNS)


  The brain and the spinal chord
• Peripheral nervous system (PNS)


  All nerves throughout the body excluding the brain and the spinal chord
• Afferent signal


  Information that arrives into the CNS
• Efferent signal


  Information leaving the CNS
• Rostral (anterior)


  Parts of the brain that are more forward (towards the face)
• Caudal (posterior)


  Parts of the brain that are further back (towards the back of the head)
• Dorsal (superior)


  Parts of the brain that are further up (towards the top of the head)
• Ventral (inferior)


  Parts of the brain that are further down (towards the base of your head)
• Medial


  Brain structures that are closer to the middle of the brain (from the nose to the middle of the back of the head)
• Lateral


  Brain structures that are closer to the edges of your brain (e.g. behind your temples)
• Coronal slice

  
• Sagittal brain slice

  
• Horizontal brain slice

  
• White matter


  Pale brain tissue that serves as pathways of communication between neurons, caused by myelin making signal transmission faster
• Gray matter


  Parts of the brain with a darker pink color that are generally dense with cell bodies
• Corpus callosum

  
• Early in development, the neural tube splits into three compartments, so it's the three vesicle stage. A week later, two of those split, and so it's called the five vesicle stage
• gyri and sulci


  raised ridges and indentations in the cortex
• Occipital lobe


  Smallest of the four main lobes, mainly for interpreting visual stimuli
• Temporal lobe


  Most ventral of the lobes with its dorsal border being marked by the lateral fissure, it helps process auditory information, and stores structures that work with language, as well as the hippocampus, which creates memories
• Parietal lobe


  Bordered by the central sulcus and the lateral fissure, mainly receives and processes sensory information
• Proprioception


  The sense of where all your body parts are located
• Primary auditory cortex (A1)


  Lets us distinguish and process sounds, temporal lobe
• Primary somatosensory cortex (S1)


  Lets us have proprioception, and process the sensory information that we get through our skin, eyes, nose, etc (parietal lobe)
• Frontal lobe


  Bordered by the lateral sulcus posteriorly, largest of the four lobes in mammals, helps us with behavior and personality, along with some motor control
• Primary motor cortex (M1)


  Contains neurons that control the movement of your body (i.e. if you activate parts of it, your leg shakes), in the frontal lobe
• Vertebral column


  Series of bones protecting the spinal chord
• Cervical


  Area of the spine that innervates the neck, shoulders, arms, and hands. C3 through C5 innervates the diaphragm, so if you get an injury up there you could asphyxiate
• Thoracic


  12 pairs of spinal nerves that innervate the trunk area and control the organs involuntary movements when the body is in fight or flight mode
• Lumbar


  5 pairs of nerves, controls parts of the legs and has wider parts like the cervical region
• Sacral


  5 pairs of nerves, innervates back part of the legs, genital organs, colon, and bladder
• The more anterior a spinal injury, the more serious, because all signals have to pass through the regions above them to reach the brain
• The more anterior the part of the spinal chord, the higher its ratio of white matter to gray matter
• The inner portion of the spine is gray matter, the outer portion is white matter, which is what does most of the transmission
• The widest part of the spine is in the cervical region
• Proximal


  More close to the CNS
• Distal


  More far from the CNS
• Somatic nervous system


  Controls our voluntary movements (skeletal muscle) and represents all parts of the PNS that are involved with the outside environment
• Autonomic nervous system


  Encompasses all branches of the PNS that deal with the internal environment, by sensing things and sending signals to smooth muscles for us to perform involuntary physical reactions
• Sympathetic nervous system

  Triggers all the physical responses to a fight-or-flight scenario (adrenaline, bronchioles dilating, etc)