Brain Anatomy and Structures

Overview

• Lecture focused on structures within and covered by the cerebral hemispheres.
• Key focus areas: basal ganglia, limbic system, ventricles.

Structures Covered

Cerebral Hemispheres

• Covers other brain structures like the midbrain and diencephalon.
• Contains basal ganglia, limbic system, ventricles.

Basal Ganglia

• Misnomer, should be "basal nuclei." Collections of cell bodies in CNS white matter.
• Components:
  • Caudate Nucleus: Head, body, tail.
  • Putamen: Lateral round structure.
  • Globus Pallidus: Medial to putamen; lateral and medial parts.
• Terminology:
  • Lentiform Nucleus: Putamen + Globus Pallidus.
  • Neostriatum: Caudate Nucleus + Putamen.
  • Other components include subthalamic nucleus and substantia nigra (not covered in detail).

Limbic System

• Functionally related nuclei and cortical areas, not anatomically distinct.
• Key Structures:
  • Hippocampus: Important in memory formation, located medially in the temporal lobe.
  • Fornix: Runs up and connects hippocampus to other parts.
  • Mammillary Bodies: Located near the end of the fornix.
  • Amygdala: Often included as part of basal ganglia but belongs to the limbic system.

Ventricles

• Develop from neural tube; contain cerebrospinal fluid (CSF).
• Components:
  • Lateral Ventricles: C-shaped, one on each side.
  • Third Ventricle: Midline structure; walls formed by thalamus.
  • Interventricular Foramina: Connect lateral ventricles to third ventricle.
  • Fourth Ventricle: Located within the pons, connected to third ventricle via cerebral aqueduct.
  • Cerebral Aqueduct: Runs within midbrain, connects third and fourth ventricles.

Summary

• Detailed examination of brain structures within cerebral hemispheres: basal ganglia, limbic system, ventricles.
• Understanding of spatial relationships between different brain parts.