Introduction to Psychology: The Brain

The Astonishing Hypothesis

• Proposed by Francis Crick
• Human experiences and identity are just behaviors of nerve cells
• Challenges common views of dualism

Dualism vs. Materialism

• Dualism: Mind and body are separate
  • Supported by philosophers like Plato and Descartes
  • Descartes' arguments:
    • Humans are capable of creativity and choice, unlike machines
    • The method of doubt: Can’t doubt the act of thinking
• Materialism: The mind is what the brain does
  • Supported by scientific consensus
  • Evidence from neuroscience suggests no separation of body and mind

Brain and Mental Life

• The brain appears as a simple, unattractive organ, yet supports complex processes
• Goal of neuroscience: Explain how the brain produces thought

Neurons: Building Blocks of the Brain

• Basic unit of the brain
• Components:
  • Dendrites: Receive signals
  • Cell body: Processes signals
  • Axon: Transmits signals
• Neurons communicate chemically via synapses

Neurotransmitters & Psychopharmacology

• Chemical communication between neurons
• Agonists: Enhance neurotransmitter effects
• Antagonists: Inhibit neurotransmitter effects
• Examples:
  • Curare: Blocks motor neurons
  • Alcohol: Inhibits inhibitory brain parts
  • Prozac: Affects serotonin for treatment of depression

Brain Functionality and Disorders

• Brain damage studies help identify function
• Disorders:
  • Apraxia: Difficulty with coordinated movements
  • Agnosia: Inability to recognize objects or faces
  • Aphasia: Language disorders

Brain Structure

• Subcortical structures: Underneath cortex, essential for basic functions
• Cortex: Outer layer, involved in complex processing
  • Divided into lobes: Frontal, Parietal, Occipital, Temporal
• Maps in the Brain: Topological representations of the body

Hemispheric Lateralization

• Right and left hemispheres have specialized functions
  • Language typically on the left, music and math on the right
• Experiments show different functionalities based on brain hemisphere

Challenges and Considerations

• Hard Problem: Understanding consciousness and subjective experience
• Ethical and Philosophical Implications:
  • Balancing scientific views with humanistic values like free will and intrinsic value
  • Potential tension between mechanistic views and spiritual beliefs

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These notes provide a foundational understanding of the brain, setting the stage for more detailed exploration in future classes.