Study Guide: Hormones and Genes in IB Psychology

Topic 1: Hormones

Definition:
- Hormones are chemical messengers secreted by the endocrine system that regulate bodily functions and influence behavior.
- Unlike neurotransmitters, hormones are slower to act but have widespread effects.

Examples:
- Cortisol: Related to stress.
- Testosterone: Associated with aggression and dominance.
- Oxytocin: Influences social bonding and trust.

How Hormones Work:
- Released into the bloodstream by glands.
- Target specific organs or cells.
- Work through feedback mechanisms to maintain balance.

Influence on Behavior:
- Hormones affect emotions, stress responses, social behaviors, and decision-making.

Research Framework (APRIL):
- Aim: Understand hormonal effects on behavior.
- Procedure: Commonly involves controlled experiments and observation.
- Results: Highlight relationships between hormone levels and specific behaviors.
- Implications: Provides insights into biological influences on behavior.
- Limitations: Ethical concerns, individual variability, and complex interactions with other factors.

Topic 2: Pheromones

Definition:
- Pheromones are chemical substances released by animals and humans to communicate and influence others' behavior.

Role:
- Affect mating behavior, social bonding, and recognition among individuals.

Key Components:
- Detection: Specialized receptors (e.g., vomeronasal organ).
- Response: Behavioral or physiological changes.
- Effects: Social interactions, bonding, and reproduction.

Human Research:
- Focuses on the subtle role of pheromones in attraction and social dynamics.
- Challenges include isolating effects and ethical concerns.

Topic 3: Genes

Nature vs. Nurture Debate:
- Nature: Behavior influenced by genetic predispositions.
- Nurture: Shaped by environmental factors.

Interaction:
- Genes and the environment interact dynamically to shape personality, intelligence, and behavior.

Epigenetics:
- Definition: Study of how external factors (e.g., stress, diet) affect gene expression without altering DNA.
- Impacts: Epigenetic changes can lead to variations in behavior and mental health.

Topic 4: Genetic Similarities

Why Study Genetic Similarities?
- Helps identify hereditary traits.
- Provides insights into disorders like depression or schizophrenia.

Methods:
- Twin Studies: Compare identical vs. fraternal twins.
- Adoption Studies: Examine differences between adopted children and biological parents.

Ethical Considerations:
- Privacy and consent in genetic research.
- Implications of genetic data for individuals and families.