AP Psychology Unit 1 Summary: Biological Basis of Behavior

Introduction

• Presenter: Mr. Sin
• Focus: Biological basis of behavior in AP Psychology.
• Emphasis on active participation and note-taking.
• Nature vs. Nurture: Now seen as a combination of both heredity (nature) and environment (nurture).

Nature vs. Nurture

• Nature: Heredity—passing traits from generation to generation.
• Nurture: Environmental influences such as family, society, and education.
• Different psychological perspectives lean towards different sides (e.g., Evolutionary approach leans towards nature).
• Epigenetics: Studies how environment affects gene expression without changing the DNA.
• Twin Studies: Used to understand heredity vs. environment (e.g., Minnesota Study of Twins).
• Plasticity: Brain’s ability to adapt through experience vs. epigenetics.

Nervous System

• Central Nervous System (CNS): Brain and spinal cord.
• Peripheral Nervous System (PNS): Connects CNS to body organs and muscles.
  • Afferent Neurons: Sensory neurons that send signals to CNS.
  • Efferent Neurons: Motor neurons that send signals from CNS.

PNS Subsystems

• Somatic Nervous System: Controls voluntary movements and senses.
• Autonomic Nervous System: Controls involuntary functions like heartbeat and digestion.
  • Sympathetic Division: Prepares the body for action (fight or flight).
  • Parasympathetic Division: Calms the body (rest and digest).

Neurons

• Types of Cells:
  • Glial Cells: Support neurons by providing nutrients and protection.
  • Neurons: Fundamental units of the nervous system that communicate using electrical impulses and chemical signals.
• Reflex Arc: Pathway involving sensory, motor, and interneurons for reflex actions.
• Neural Transmission:
  • Action Potential: Electrical impulse that travels down a neuron’s axon.
  • Synapse: Gap where neurotransmitters are released to communicate with other neurons.

Neurotransmitters and Hormones

• Key Neurotransmitters:
  • Acetylcholine: Muscle action, learning, memory.
  • Dopamine: Movement, learning, attention, emotion.
  • Serotonin: Mood, hunger, sleep, arousal.
• Endocrine System: Hormones regulate various bodily functions, slower than nervous system.

Drugs and Their Effects

• Psychoactive Drugs: Affect perception and mood.
• Agonists: Increase neurotransmitter action.
• Antagonists: Decrease neurotransmitter action.
• Substance Types:
  • Stimulants: Increase neural activity (e.g., caffeine).
  • Depressants: Decrease neural activity (e.g., alcohol).

Brain Structure and Function

• Regions of the Brain:
  • Hindbrain: Includes medulla, pons, cerebellum.
  • Midbrain: Processes visual and auditory information.
  • Forebrain: Includes cerebrum, thalamus, limbic system.
• Lobes of the Cerebrum:
  • Frontal Lobe: Higher-level thinking, voluntary movement.
  • Parietal Lobe: Sensory information processing.
  • Temporal Lobe: Auditory processing, memory, emotion.
  • Occipital Lobe: Visual processing.

Brain Research

• Phineas Gage: Case study revealing brain’s role in personality.
• Split-Brain Research: Insight into hemispheric specialization.
• Neuroimaging Techniques:
  • EEG: Measures electrical activity of neurons.
  • fMRI: Shows brain activity related to metabolic function.

Sleep and Consciousness

• Circadian Rhythm: Biological clock regulating sleep-wake cycles.
• Sleep Stages:
  • Non-REM: Light to deep sleep.
  • REM: Associated with dreaming.
• Sleep Disorders: Insomnia, sleep apnea, narcolepsy.

Sensation and Perception

• Sensation: Process of taking in information from the environment.
• Thresholds:
  • Absolute Threshold: Minimum stimulation needed to detect a stimulus.
  • Difference Threshold: Minimum difference needed to detect a change in stimuli.
• Sensory Adaption: Decreased sensitivity to constant stimuli.

Sensory Systems

• Visual System: Eye structure, rods and cones, color theories.
• Auditory System: Sound wave properties, pitch theories.
• Chemical System:
  • Olfaction: Smell.
  • Gustation: Taste.
• Touch and Pain: Sensory receptors and pain theories like gate control.

Conclusion

• Emphasis on comprehensive understanding of biological basis of behavior.
• Encouragement to use additional study resources and materials.