What makes up the CNS?
brain, brainstem, spinal cord
What makes up the PNS?
cranial nerves and ganglia, spinal nerves and dorsal root ganglia, sympathetic and parasympathetic systems, enteric system
What is white matter?
Bundles of myelinated axons
What is grey matter?
concentrated areas of cell bodies and dendrites
What are the three classifications of white matter?
- Projection fibres
- Commissural fibres
- Association fibres
What are projection fibres?
Bundles of axons that relay impulses between the cortex, brainstem, and spinal cord
What are commissural fibres?
Fibres that cross between hemispheres
ex: corpus callosum
What are association fibres?
Fibres that connect cortical areas within a hemisphere, can be short (motor to sensory connections) or long (lobe connections)
What is a cortex?
A folded layer of gray matter on the outer surface of the brain
What is a gyrus?
An outward fold
What is a sulcus?
An inward fold
What is a fissure?
A very deep sulcus
What divides the frontal and parietal lobes?
the central sulcus
What divides the temporal and frontal lobes?
Sylvian fissure
What divides the parietal and occipital lobes?
parietal-occipital sulcus
*only seen from a medial view, no lateral landmark
What structures make up the brainstem?
Midbrain, pons, and medulla
What connects the left and right thalamus?
Interthalamic adhesions
What structure allows the spinal cord and brainstem to connect to the rest of the brain?
Foramen Magnum
What occurs at the foramen magnum?
this is the level of the cervico-medullary junction where the cervical spinal cord ends and the medulla begins
What structures sit in the posterior fossa of the skull?
Brainstem and cerebellum
What structure sits in the middle fossa of the skull?
Inferior surface of the temporal lobe
What structure sits in the anterior fossa?
Inferior surface of the frontal lobe
What separates the anterior and middle fossae of the skull?
Lesser wing of the sphenoid bone
