AP Psychology Unit 2 Topic 6: The Brain

Overview

• Purpose: Understand key brain structures, their functions, and significant contributions to brain research.
• Statistics:
  • 86 billion neurons
  • 100,000 miles of axons
  • 10 trillion synapses
  • Consumes 20% of body's oxygen

Historical Contributions

• Hippocrates: Speculated brain divided into two halves.
• Paul Broca:
  • Identified Broca's area in the left frontal lobe.
  • Broca's area controls facial muscles needed for speech.
  • Broca's aphasia: Loss of ability to produce language but can comprehend.
• Carl Wernicke:
  • Identified Wernicke's area in the left temporal lobe.
  • Wernicke's area responsible for meaningful speech.
  • Wernicke's aphasia: Loss of speech comprehension and meaningful speech.

Brain Structure Overview

• Central Nervous System: Brain and spinal cord.
• Regions of the Brain:
  • Hindbrain: Pons, medulla oblongata, cerebellum.
  • Midbrain: Relay station for visual and auditory information.
  • Forebrain: Complex thoughts and behaviors.

Hindbrain

• Medulla: Autonomic functions like cardiovascular and respiratory regulation.
• Pons:
  • Connects medulla with cerebellum.
  • Coordinates movement; involved in sleep and dreams.
• Cerebellum: Balance and coordination, motor learning.
• Brain Stem: Essential for autonomic functions.

Midbrain

• Reticular Formation: Arousal and sleep-wake cycle.
• Reticular Activating System: Filters stimuli, sends important information to thalamus.

Forebrain

• Cerebrum: Complex processes beyond survival.
• Cerebral Cortex: Higher cognitive functions, divided into lobes.
• Corpus Callosum: Connects two hemispheres.

Lobes of the Brain

• Frontal Lobe:
  • Prefrontal cortex: Judgment, complex thought.
  • Motor cortex: Voluntary movement.
• Parietal Lobe: Sensory information, somatosensory cortex.
• Occipital Lobe: Visual processing.
• Temporal Lobe:
  • Wernicke's area: Language comprehension.
  • Angular gyrus: Reading and auditory processing.
  • Auditory cortex: Processes hearing.

Limbic System

• Hippocampus: Memory creation.
• Amygdala: Emotional reactions, particularly fear and aggression.
• Hypothalamus: Homeostasis, regulates drives and hormones.

Other Structures

• Thalamus: Sensory information relay to forebrain.
• Nucleus Accumbens: Pleasure, reward circuit, motivation.
• Basal Ganglia: Intentional body movement, links thalamus with motor cortex, associated with Parkinson's and other movement disorders.

Conclusion

• Practice questions available.
• Resources: Review packets, practice sheets, and quizzes available online.
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