Key Assessment Study Guide

1. Theory vs. Hypothesis

• Theory: A broad explanation or framework for understanding phenomena, based on extensive research and evidence. It’s often used to generate hypotheses. For example, the theory of evolution explains the diversity of life.

• Hypothesis: A specific, testable prediction derived from a theory. For example, “Students who sleep eight hours before an exam will perform better than those who sleep less.”

2. The Scientific Method

1. Ask a question: Identify a problem or phenomenon.

2. Do background research: Explore what’s already known.

3. Form a hypothesis: Develop a testable prediction.

4. Conduct an experiment: Test the hypothesis through controlled methods.

5. Analyze data: Use statistics to interpret results.

6. Draw conclusions: Determine whether the hypothesis is supported.

7. Report results: Share findings for replication.

3. Reliability and Validity

• Reliability: Consistency of a measurement over time. A reliable test gives similar results when repeated.

• Validity: Accuracy of a measurement. A valid test measures what it is intended to measure 

4. Research Designs

• Correlational: Examines relationships between variables without manipulation. Example: Studying the relationship between stress and sleep. Correlation ≠ causation.

• Descriptive: Observes and describes behaviors or phenomena without influencing them. Examples: case studies, surveys, naturalistic observation.

• Experimental: Involves manipulation of one variable (independent variable) to observe its effect on another (dependent variable), allowing for causal conclusions.

5. Key Terms in Experiments

• Experimental group: Participants exposed to the treatment or independent variable.

• Control group: Participants not exposed to the treatment, serving as a baseline.

• Independent variable (IV): The variable manipulated by the researcher.

• Dependent variable (DV): The variable measured to see the effect of the IV.

6. Generalizability and Internal Validity

• Generalizability (External Validity): The extent to which findings can be applied to other populations, settings, or times.

• Internal Validity: The degree to which an experiment is free from confounding variables, ensuring the IV causes the changes in the DV.

7. Ethical Considerations

• Institutional Review Boards (IRBs): Panels that review research proposals to ensure ethical standards are met.

• Informed Consent: Participants must be fully informed about the study and agree to participate voluntarily.

• Deception: Misleading participants about the study’s purpose, only allowed when necessary and justified.

• Debriefing: Explaining the true purpose of the study to participants afterward.

8. Parts of the Neuron

• Dendrites: Receive signals from other neurons.

• Cell Body (Soma): Processes information.

• Axon: Transmits signals to other neurons or muscles.

• Myelin Sheath: Insulates the axon to speed up signal transmission.

• Axon Terminals: Release neurotransmitters to communicate with other neurons.

9. Action Potential

1. A stimulus causes the neuron's membrane to depolarize.

2. Sodium ions (Na⁺) flow in, making the inside positive.

3. Potassium ions (K⁺) flow out, repolarizing the neuron.

4. The impulse travels, triggering neurotransmitter release at the axon terminals.

10. Neurotransmitters and Communication

• Neurotransmitter: Chemical messenger released by neurons to transmit signals across synapses.

• Process:

  1. Action potential reaches axon terminal.

  2. Neurotransmitters are released into the synapse.

  3. They bind to receptors on the next neuron, triggering or inhibiting an action potential.

11. Functions of Basic Neurotransmitters

• Acetylcholine: Muscle action, memory.

• Dopamine: Reward, pleasure, and movement.

• Serotonin: Mood, appetite, and sleep.

• Norepinephrine: Alertness, arousal.

• GABA: Inhibitory, reduces neural activity.

• Glutamate: Excitatory, enhances learning.

12. Structure of the Nervous System

• Central Nervous System (CNS): Brain and spinal cord.

• Peripheral Nervous System (PNS): Nerves outside the CNS, including:

  • Somatic: Voluntary muscle control.

  • Autonomic: Involuntary functions, with sympathetic (fight-or-flight) and parasympathetic (rest-and-digest) systems.

13. Parts of the Brain

• Frontal Lobe: Decision-making, motor control.

• Parietal Lobe: Sensory processing.

• Temporal Lobe: Hearing, memory.

• Occipital Lobe: Vision.

• Cerebellum: Balance, coordination.

• Brainstem: Basic life functions (e.g., breathing, heart rate).

14. Split-Brain Experiments

Conducted by Roger Sperry, these studies explored individuals whose corpus callosum (connecting brain hemispheres) was severed. Results showed:

• Left hemisphere: Language and logic.

• Right hemisphere: Spatial and creative tasks. Split-brain patients demonstrated independent hemisphere functions.

15. Philosophical Ideas

• The Blank Slate (Tabula Rasa): Humans are born with no inherent traits; experiences shape personality (John Locke’s idea).

• The Ghost in the Machine: The mind and body are separate entities (dualism, linked to Descartes).

• The Noble Savage: Humans are inherently good, corrupted by society (Jean-Jacques Rousseau).