Nervous System Anatomy: Focus on the Brain

Overview

• The brain's major areas:
  • Cerebrum
  • Cerebellum
  • Brainstem

Cerebrum

• Lobes of the Cerebrum:
  • Temporal Lobe
    • Separated from the frontal and parietal lobes by the lateral cerebral sulcus/fissure.
  • Frontal Lobe
  • Parietal Lobe
    • Separated from the frontal lobe by the central sulcus.
  • Occipital Lobe
• Cerebral Hemispheres
  • Separated by the longitudinal fissure.
• Gyri and Sulci:
  • Gyri: Ridges of the brain.
  • Sulci: Shallow grooves of the brain.

Cerebellum

• Separated from the cerebrum by the transverse fissure.
• Composed of two hemispheres, divided into anterior and posterior lobes.
• Vermis: Connects the two hemispheres, named for its worm-like appearance.
• Arbor Vitae: White matter inside the cerebellum, known as the "tree of life."
• Folia: Gray matter surrounding the arbor vitae.

Brainstem

• Midbrain
  • Contains the aqueduct of the midbrain, part of the ventricular system.
  • Cerebral Peduncles: Motor tracts from the cerebrum.
  • Corpora Quadrigemina: Four bodies; superior colliculi (superior bodies) and inferior colliculi (inferior bodies).
• Pons: Part of the brainstem above the medulla, separated from the cerebellum by the fourth ventricle.
• Medulla: Connects to the spinal cord.

Diencephalon

• Thalamus
  • Egg-shaped mass; relay center for sensory information.
  • Connected by interthalamic adhesion (intermediate mass).
  • Third Ventricle: Surrounds the thalamus, torus-shaped.
• Hypothalamus
  • Located below the thalamus, near the optic chiasm.
  • Connects to the pituitary gland, interface between nervous and endocrine systems.
• Epithalamus
  • Includes the pineal gland, which secretes melatonin.

Other Structures

• Corpus Callosum: White matter connecting the two cerebral hemispheres.
• Fornix: White matter structure with association tracts for intra-hemispheric communication.
• Septum Pellucidum: Divides the two lateral ventricles.

Ventricular System

• Lateral Ventricles: Drain into the third ventricle.
• Aqueduct of the Midbrain: Connects the third and fourth ventricles.
• Fourth Ventricle: Located between the cerebellum and pons.

---

This lecture focused on brain anatomy, highlighting the cerebrum, cerebellum, brainstem, and diencephalon, along with their associated structures and functions. Further details on nerves will be covered in another video.