Overview of the Brain

Presenter: Dr. Mike

Introduction

• Overview of the brain
• Discussion on brain development and structures
• The brain starts as a hollow tube (neural tube) at about 3 weeks of gestation

Development of the Brain

Neural Tube to Brain Structures

• The neural tube develops and swells, forming 5 important vesicles:

1. Telencephalon

• Telencephalon = "end of the brain"
• Develops into the cerebrum
• Cerebrum Characteristics:
  • Largest part of the brain
  • Comprised of two hemispheres
  • Longitudinal fissure separates left and right hemispheres
  • Laterality:
    • Left hemisphere controls the right side of the body
    • Right hemisphere controls the left side
    • Language comprehension predominantly in the left hemisphere

Cerebral Cortex

• Outer 1-5 mm of the cerebrum
• The seat of consciousness
• Divided into lobes:
  • Frontal Lobe:
    • Contains primary motor cortex for movement initiation
    • Higher order reasoning and behavior control
  • Parietal Lobe:
    • Contains somatosensory cortex for sensory information (touch, pain, temperature, etc.)
  • Occipital Lobe:
    • Responsible for vision
  • Temporal Lobe:
    • Responsible for hearing
  • Insula:
    • Associated with taste

Deeper Structures of the Cerebrum

• Basal Ganglia: Initiates and smooths motor movement
• Limbic System: Important for emotion

2. Diencephalon

• Diencephalon = "between brain"

Key Structures:

• Thalamus:
  • Relay/sorting center of sensory information
  • Directs signals to the appropriate cortical areas
• Hypothalamus:
  • Master regulator of the endocrine and autonomic nervous systems
  • Controls hormones related to various bodily functions (e.g., growth, emotion)

3. Mesencephalon

• Mesencephalon = "middle brain"
• Comprises the midbrain

4. Metencephalon

• Metencephalon
  • Contains the pons and cerebellum
• Cerebellum Functions:
  • Important for tone, balance, and coordination of motor activities

5. Myelencephalon

• Myelencephalon = "marrow brain"
• Contains the medulla oblongata
• Functions:
  • Basic bodily functions: heart rate, breathing, blood pressure
  • Houses nuclei of cranial nerves
  • Conduit for info between brain and body

Conclusion

• Summary of the brain structures and their functions
• Understanding the telencephalon, diencephalon, mesencephalon, metencephalon, and myelencephalon is crucial
• Encouragement to like and subscribe for more content

Key Terms:

• Laterality
• Cerebral Cortex
• Basal Ganglia
• Limbic System
• Thalamus
• Hypothalamus
• Cerebellum
• Medulla Oblongata