Get Psyched with Tim Stedman: AP Psychology Unit 1 Review

Introduction

• Presenter: Tim Stedman
• Topic: Unit 1 of AP Psychology - The Biological Basis of Behavior
• Key Concept: Nature vs. Nurture

Biological Influences on Behavior

Nature vs. Nurture

• Nature: Genetic inheritance from parents, including physical and psychological traits.
• Nurture: Environmental influences and experiences shaping behavior from infancy to adulthood.
• Interaction: Both nature and nurture constantly interact to shape behavior.

Evolutionary Psychology

• Darwin's Theory of Evolution: Traits enhancing survival and reproduction are likely passed to next generations.
• Misuse Example: Eugenics aimed at improving the human population through selective breeding.

Research Strategies

• Twin Studies: Study identical twins under various conditions to understand environmental influence.
• Adoption Studies: Separate genetic influence from the home environment.
• Family Studies: Analyze traits across generations to distinguish genetic vs. environmental influences.

Nervous System Structure

Central Nervous System (CNS)

• Components: Brain and spinal cord.
• Function: Command center processing sensory data, coordinating responses.

Peripheral Nervous System (PNS)

• Components: Nerves branching from CNS to rest of the body.
• Subdivisions:
  • Somatic: Voluntary movement and sensory information.
  • Autonomic: Involuntary functions (heart rate, digestion, etc.).
    • Sympathetic: Fight or flight response.
    • Parasympathetic: Restores body to normal functioning.

Neuronal Communication

Neurons

• Role: Primary communication cells in the nervous system.
• Components:
  • Nucleus: Contains genetic information.
  • Cell Body (Soma): Provides structural support.
  • Dendrites: Receive messages.
  • Axon: Sends messages, covered by the myelin sheath for faster transmission.

Types of Neurons

• Sensory Neurons: Collect information from senses.
• Motor Neurons: Control muscles and release hormones.
• Interneurons: Direct messages throughout the CNS.

Reflex Arcs

• Example: Reflex response to hot stove involves sensory, motor, and interneurons, bypassing the brain.

Neurotransmission

• Action Potential: Electrical charge traveling down the axon.
• All or Nothing Principle: Action potential occurs only if stimulation threshold is met.
• Reuptake: Reabsorbing neurotransmitters for reuse.

Disorders

• Multiple Sclerosis/Myasthenia Gravis: Autoimmune disorders affecting neuron function.

Neurotransmitters

• Dopamine: Pleasure and reward systems.
• Serotonin: Regulates mood, appetite, and sleep.
• Norepinephrine: Alertness and arousal.
• Glutamate: Cognitive functions.
• GABA: Major inhibitory neurotransmitter, slows brain activity.
• Endorphins: Natural painkillers.
• Substance P: Regulates pain perception.
• Acetylcholine: Stimulates muscle contractions.

Endocrine System

• Chemical Messengers: Hormones affecting behavior.
• Key Hormones:
  • Adrenaline: Fight or flight response.
  • Leptin: Regulates energy balance.
  • Ghrelin: Stimulates appetite.
  • Melatonin: Prepares for sleep.
  • Oxytocin: Social bonding and reproduction.

Psychoactive Drugs

• Agonists/Antagonists: Affect neurotransmitter activity.
• Reuptake Inhibitors: Increase neurotransmitter levels.
• Types of Drugs:
  • Stimulants: Increase brain activity.
  • Depressants: Slow down CNS activity.
  • Hallucinogens: Alter perception.
  • Opioids: Pain relief and euphoria.

Brain Structure and Functions

Brain Structures

• Brainstem: Controls automatic functions.
• Cerebellum: Motor control and coordination.
• Limbic System: Emotional center, includes thalamus, hypothalamus, hippocampus, and amygdala.
• Cerebral Cortex: Complex thoughts, divided into lobes (occipital, temporal, parietal, frontal).

Hemispheric Specialization

• Left Hemisphere: Language.
• Right Hemisphere: Spatial reasoning and facial recognition.

Plasticity

• Functional Plasticity: Shifting functions to undamaged areas.
• Structural Plasticity: Changing physical structure through learning.

Consciousness and Sleep

Sleep Cycles

• Stages of Sleep: NREM and REM.
• Sleep Disorders: Insomnia, narcolepsy, sleep apnea, etc.

Theories

• Restorative Theory: Sleep for body repair.
• Adaptive Theory: Sleep for survival.
• Dream Theories: Activation-synthesis and memory consolidation theories.

Sensation and Perception

Sensory Processes

• Vision: Light waves processed by rods and cones.
• Hearing: Sound waves processed by hair cells in the cochlea.
• Smell and Taste: Chemical senses using olfactory and gustatory receptors.
• Touch and Pain: Detected by mechanoreceptors, thermoreceptors, and nociceptors.

Sensory Theories

• Vision Theories: Trichromatic and opponent-process theories.
• Hearing Theories: Frequency, volley, and place theories.

Sensory Disorders

• Vision Disorders: Nearsightedness, farsightedness, color blindness.
• Hearing Disorders: Conductive and sensorineural hearing loss.

Conclusion

• Key Takeaway: Understanding the biological basis of behavior in psychology.
• Next Topic: Review on Cognition.