Key Terms
Neural groove
The indentation along the dorsal surface Neural fold: the raised edges on either side Neural tube: forms when the folds
Neuraxis
The central axis of the nervous system, running from the inferior tip of the spinal cord to the anterior surface of the
Cephalic flexure
A bend between the brain stem and forebrain. In humans (bipeds), this flexure reorients the neuraxis so that "anterior"
Hippocampus
Critical for long-term memory formation; located in the medial temporal lobe
Amygdala
Emotional responses and memory; also in medial temporal lobe
Function
Compares the motor commands sent from the cerebrum to the spinal cord with actual sensory feedback from the periphery.
Largest white matter connection
Cerebellum to pons. This follows from shared embryonic origin (both from metencephalon).
Structure
Retains the basic neural tube shape. Long and straight with a small central canal.
Regional organization
Cervical, thoracic, lumbar, sacral. Named for where the spinal nerves exit.
Venous return
Blood drains through dural sinuses → transverse sinuses → sigmoid sinuses → jugular veins.
Superior sagittal sinus
Runs along the longitudinal fissure; absorbs CSF from the meninges.
Produced by
Choroid plexuses (specialized ependymal cells lining capillaries in the ventricles)
Composition
Essentially water, small molecules, electrolytes; clear; limited blood components
Functions
1. Removes metabolic wastes from CNS tissue 2.
Total production
Approximately 500 mL per day; continuously produced and circulating