Lecture Notes: Understanding the Brain and Phrenology

Introduction to Phrenology

• Franz Joseph Gall:
  • Early 1800s German physician.
  • Developed phrenology: Belief that skull morphology indicated personality traits.
  • Considered pseudoscience today, but initiated the idea that different brain areas control specific behaviors.

Brain Function Localization

• Different parts of the brain have specific functions:
  • Vision, movement, memory, speech, facial recognition.
• Biological activity is linked to psychological events.
• Mind as brain activity: "The mind is what the brain does."

Central Nervous System (CNS) vs Peripheral Nervous System (PNS)

• CNS:
  • Command center making big decisions.
• PNS:
  • Sensory neurons gather information to report to CNS.

Case Study: Phineas Gage

• Incident: Iron rod through Gage’s head (1848).
• Aftermath:
  • Survived with significant personality changes.
  • Example of brain function localization affecting behavior.

Misconceptions About Brain Usage

• Myth: People only use 10% of their brain.
• Reality: The entire brain is active during simple tasks.

Evolution of the Brain

• Brain structure:
  • Less complex animals: Basic survival functions.
  • More complex animals: Reason, memory, prediction.
• Old vs New Brain:
  • Old brain (brainstem, medulla, pons, cerebellum): Basic functions.
  • New brain (cerebral cortex, lobes): Higher functions.

Brain Anatomy and Functions

• Brain Stem:
  • Brainstem: Central core for automatic functions.
  • Medulla: Heartbeat and breathing.
  • Pons: Coordination of movement.
  • Thalamus: Sensory information processing.
  • Reticular Formation: Arousal and pain perception.
  • Cerebellum: Movement control and learning.
• Limbic System:
  • Amygdala: Memory consolidation, fear, aggression.
  • Hypothalamus: Body regulation, endocrine control.
  • Hippocampus: Learning and memory.
• Cerebral Cortex:
  • Hemispheres: Left and right, connected by corpus callosum.
  • Lobes:
    • Frontal: Speech, planning, personality.
    • Parietal: Touch, body position.
    • Occipital: Sight.
    • Temporal: Sound, speech comprehension.

Higher Brain Functions

• Motor Cortex: Voluntary movement control.
• Sensory Cortex: Sensation processing.
• Association Areas: Higher mental functions (thinking, learning).

Conclusion

• Key Takeaways:
  • Importance of understanding brain structure and function.
  • Interconnectedness of biology and psychology.
• Next Steps: Examination of sensation and perception in future lectures.