Inferior/Ventral Toward belly side
Medial Toward midline
Rostal/Anterior Toward head of 4-legged animal
Caudal/Posterior Toward tail of 4-legged animal
Superior/Dorsal Toward back of 4-legged animal
An imaginary line that runs the length of the spinal cord to the front
Neuraxis of the brain.
Ipsilateral Structures that are on the same side of the midline.
Contralateral Structures that are on opposite sides of the midline.
Lateral Structures to the side of the midline.
Proximal Close to center
Distal Far away from center
Midline An imaginary line that divides us into 2 halves.
Coronal sections Frontal sections
Divide the system from front to back.
Sagittal sections Parallel to midline
Allows us to view brain structures from side.
Mid-sagittal section Divides brain into 2 equal parts
Horizontal/Axial section Divides the brain from top to bottom. Meninges
1. Dura mater
Means “hard mother” in Latin
Composed of leather like tissue that follows the outlines of the skull bones.
2. Arachnoid layer
Under dura mater
More delicate than dura mater
Structure looks like a spiders web
In between Arachnoid layer and Pia mater is subarachnoid space.
3. Pia mater
Sticks to outside of the brain
Dura mater and pia mater cover nerves that exit the brain and spinal cord (PNS).
Meningitis- infection of the meninges by various viruses and bacteria.
Meningiomas- tumors that arise in meninges.
Cerebrospinal fluid (CSF)
CSF is secreted within the ventricles (hollow spaces in brain).
Ventricles are lined with choroid plexus, which converts material from blood
supply to CSF (similar in composition to clear blood plasma).
CSF cushions the brain from bumps and prevents neurons from responding to
pressure on the brain.
Neuron firing due to pressure is maladaptive- e.g. pressure on brain due to
tumors causes seizures.
CSF is found in the central canal of the spinal cord and 4-brain ventricles- 2
lateral ones (one in each hemisphere) and 2 in the brainstem.
The 4 ventricle is continuous with the central canal (runs down the spinal
cord at midline).
Below the 4 ventricle, there is a small opening to allow the CSF to flow into
the subarachnoid space.
CSF is turned over 3 times a day (old CSF is reabsorbed into the blood at the
top of the head).
CSF produced by choroid plexus.
Flows from lateral ventricles to the 3 and 4 ventricles and into the central
canal. At the base of the cerebellum, it exits into the