In-Depth Notes on Brain Anatomy and Function

Cerebral Structure

• The brain consists of the left and right hemispheres.
• Key regions discussed:
  • Lateral Ventricle: Located at the core of the cerebral structure.
  • Corpus Callosum: Acts as the ceiling of the lateral ventricle, connecting the two hemispheres.
  • Fornix: Serves as the floor of the lateral ventricle, playing a role in the limbic system.

Brainstem Anatomy

• Medulla Oblongata: Identified as the first visible bump on the brainstem, crucial for autonomic functions.
• Pons: The second bump, involved in regulating vital functions and relaying signals between different parts of the brain.

Meninges and Cerebrospinal Fluid (CSF)

• The meninges consist of three layers:
  1. Arachnoid Mater: Named after the web-like appearance; contains villi to absorb/recycle cerebrospinal fluid.
  2. Pia Mater: The innermost layer that closely adheres to the surface of the brain and spinal cord.

Relationship between Meninges and Vertebral Structure

• Important connections:
  • Meninges connect to the inside of the skull, reinforcing protection for the brain.
  • The spinal cord has how many vertebrae? 26 vertebrae total:
  • 7 cervical vertebrae
  • 12 thoracic vertebrae

Neural Pathways and Sensory Fibers

• Sensory Pathways:
  • Sensory fibers enter through the dorsal root ganglion, a collection of cell bodies.
  • Fibers: Primarily Aβ sensory fibers, responsible for transmitting sensory information.
• Dorsal root ganglion structure is important for understanding reflexes and sensory processing.

Cerebral Control and Motor Function

• Contralateral Control: The right side of the cerebrum governs the left side of the body and vice versa.
• Impact of injuries:
  • If a patient is paralyzed on the right side, the left hemisphere of the brain is typically affected.
• Broca's Area: A critical region associated with speech production; damage here can lead to aphasia, a speech disorder.

Summary of Key Terms

• Cerebral Hemispheres: Left and right parts of the brain.
• Lateral Ventricle: Contains cerebrospinal fluid; central part of cerebral anatomy.
• Medulla Oblongata & Pons: Key parts of the brainstem.
• Arachnoid & Pia Mater: Meninges involved in protection and fluid regulation.
• Dorsal Root Ganglion: Critical in sensory pathway functions.
• Contralateral Control: Body side movement controlled by the opposite brain hemisphere.