| Term | Definition |
|---|---|
Theory | A broad explanation of something |
Hypothesis | A specific, testable prediction |
Null hypothesis (H_0) | Predicts no relationship or effect |
Alternative hypothesis (H_A) | Predicts a relationship or effect |
Scientific evidence | Information collected systematically using scientific methods |
Anecdotal evidence | Evidence based on personal experiences or individual stories |
Falsifiability | A claim can be tested and potentially shown to be wrong |
Accuracy | Matches real-world observations |
Consistency | Agrees with other findings and has few exceptions |
Scope | Explains a wide range of situations |
Simplicity | Prefers the simplest reasonable explanation when explanations work equally well |
Fruitfulness | Leads to new research and testable predictions |
Inductive reasoning | Start with specific observations and form a general conclusion |
Deductive reasoning | Start with a general theory and make a specific prediction |
Independent variable (IV) | What the researcher changes or compares |
Dependent variable (DV) | What the researcher measures |
Operational definition | The exact way a variable is defined and measured |
Confounding variable | An outside factor that could affect the results |
Random assignment | Placing participants into groups by chance |
Experiment | Manipulates an IV to test its effect on a DV |
Correlational study | Measures the relationship between variables |
Survey research | Collects answers through questionnaires or interviews |
Quasi-experimental research | Compares existing groups without random assignment |
Longitudinal research | Follows the same participants over time |
Correlation | Means two variables are related |
Correlation coefficient | Represented by r, indicating the strength and direction of a linear relationship between two variables. |
Strong positive relationship | When r = +0.90. |
Weak positive relationship | When r = +0.20. |
Moderate negative relationship | When r = -0.50. |
No linear relationship | When r = 0. |
Positive correlation | Both variables tend to increase together. |
Negative correlation | As one variable increases, the other tends to decrease. |
Strength of correlation | Values closer to +1 or -1 indicate stronger linear relationships. |
Research scenario method | A five-step method to answer research questions. |
Step 1 of research scenario method | Identify the research question. |
Step 2 of research scenario method | Identify the research design. |
Step 3 of research scenario method | Identify the IV and DV if applicable. |
Step 4 of research scenario method | Explain what the results could mean. |
Step 5 of research scenario method | Identify one limitation or confounding variable. |
Frontal lobe | Involved in planning, decision-making, problem-solving, and self-control. |
Parietal lobe | Processes touch, temperature, and body awareness. |
Temporal lobe | Processes sound, language comprehension, and memory. |
Occipital lobe | Processes visual information. |
Brainstem | Controls essential automatic functions such as breathing, heart rate, and blood pressure. |
Cerebellum | Coordinates balance, movement, posture, and motor learning. |
Limbic system | Involved in emotion, motivation, reward, and memory. |
Amygdala | Processes emotion and fear. |
Hippocampus | Involved in the formation of new long-term memories. |
Hypothalamus | Regulates hunger, thirst, temperature, and other biological functions. |
Thalamus | Major relay station for sensory information, except smell. |
Central nervous system (CNS) | Consists of the brain and spinal cord. |
Peripheral nervous system (PNS) | Nerves outside the brain and spinal cord. |
Somatic nervous system | Controls voluntary movement and sensory information. |
Autonomic nervous system | Regulates automatic bodily functions. |
Sympathetic nervous system | Prepares the body for fight or flight responses. |
Parasympathetic nervous system | Promotes rest and digest functions. |
Action potential | An electrical signal traveling down a neuron. |
Resting membrane potential | Approximately -70 mV. |
Threshold of excitation | Approximately -50 mV; when reached, an action potential occurs. |
EPSP | Excitatory postsynaptic potential; moves the neuron toward firing. |
IPSP | Inhibitory postsynaptic potential; moves the neuron away from firing. |
Neurotransmission | Neurons communicate chemically across the synapse using neurotransmitters. |
Neurotransmitters | Chemical messengers that bind to receptors on the receiving cell. |
Reuptake | Removes neurotransmitters from the synapse by taking them back into the sending neuron. |
Enzymes | Can break down neurotransmitters. |
Sensation | Detecting physical information from the environment through your senses. |
Perception | Organizing and interpreting detected information. |
Absolute threshold | The minimum stimulus intensity that can be detected. |
Difference threshold | The smallest difference between two stimuli that a person can detect. |
Signal detection theory | Examines how people decide whether a stimulus is present when there is uncertainty or background noise. |
Hit | You detect a signal that is present. |
Miss | You fail to detect a signal that is present. |
False alarm | You report a signal that is not present. |
Correct rejection | You correctly report that no signal is present. |
Bottom-up processing | Starts with sensory information and builds toward an interpretation. |
Top-down processing | Uses previous knowledge, expectations, and context to interpret information. |
Vision | Receptor: Retina; Main brain area: Occipital lobe. |
Hearing | Receptor: Hair cells in the cochlea; Main brain area: Temporal lobe. |
Touch | Receptor: Sensory receptors in skin; Main brain area: Parietal lobe. |
Smell | Receptor: Olfactory receptors; Main brain area: Olfactory bulb and related areas. |
Taste | Receptor: Taste receptor cells; Main brain area: Gustatory cortex. |
Selective attention | Focusing on one source of information while ignoring others. |
Dichotic listening | A task in which different auditory information is presented to each ear. |
Divided attention | Trying to pay attention to more than one task at a time. |
Inattentional blindness | Failing to notice something visible because your attention is focused elsewhere. |
Attention | What information you are focusing on. |
Awareness | What you consciously notice or experience. |
Memory | Involves taking in information, keeping it, and accessing it later. |
Encoding | Getting information into memory. |
Storage | Keeping information in memory. |
Retrieval | Accessing stored information. |
Explicit memory | Memories you consciously recall, such as facts and personal experiences. |
Implicit memory | Memory expressed through skills or learned responses without consciously recalling the learning experience. |
Recall | Producing information from memory without the answer being shown. |
Recognition | Identifying information you have encountered before. |
Proactive interference | Older information makes it harder to remember newer information. |
Retroactive interference | Newer information makes it harder to remember older information. |