CALIFORNIA STATE UNIVERSITY
PSYCHOLOGY MIDTERM EXAM 2026
PRACTICE QUESTIONS WITH ANSWERS
ORIGINAL QUESTIONS, DETAILED
RATIONALES & STUDY GUIDE
1. Which statement best describes the primary goal of psychological
science?
A. To prove that human behavior is determined primarily by biology
B. To systematically describe, explain, predict, and influence behavior
and mental processes
C. To diagnose every unusual behavior as a psychological disorder
D. To eliminate subjective experiences from psychological research
Answer: B. To systematically describe, explain, predict, and
influence behavior and mental processes
Rationale: Psychology is a scientific discipline concerned with
understanding behavior and mental processes. Its goals traditionally
include describing what happens, explaining why it happens,
predicting when it may happen, and, when appropriate and ethical,
influencing or changing behavior. Psychology does not assume that
behavior is exclusively biological, nor does it define unusual behavior
automatically as pathological.
2. A researcher observes students in a university library without
interacting with them and records how often they use electronic
devices. Which research method is being used?
A. Naturalistic observation
B. Experimental manipulation
1
,C. Case study
D. Survey research
Answer: A. Naturalistic observation
Rationale: Naturalistic observation involves systematically observing
and recording behavior in its normal environment without directly
manipulating the situation. The researcher is not assigning students to
conditions or changing their environment. A survey would require
participants to provide self-reported information, while an experiment
would involve manipulation of an independent variable.
3. A psychologist wants to determine whether sleep deprivation
causes poorer memory performance. Which research design would
provide the strongest evidence for a causal relationship?
A. Correlational study
B. Case study
C. Controlled experiment
D. Naturalistic observation
Answer: C. Controlled experiment
Rationale: A controlled experiment allows researchers to manipulate
an independent variable—in this case, sleep deprivation—and
measure its effect on a dependent variable such as memory
performance. Random assignment and control over relevant variables
strengthen causal inference. Correlation can identify relationships but
cannot by itself establish causation.
4. A researcher finds that students who spend more hours studying
tend to earn higher exam scores. What does this finding
demonstrate?
2
,A. That studying definitely causes higher scores
B. A positive correlation between studying and exam performance
C. A negative correlation between studying and exam performance
D. That exam performance causes students to study more
Answer: B. A positive correlation between studying and exam
performance
Rationale: A positive correlation means that two variables tend to
increase or decrease together. Here, greater study time is associated
with higher exam scores. However, correlation alone cannot establish
causation because other factors—such as motivation, prior knowledge,
or time-management skills—could influence both variables.
5. What is the primary purpose of random assignment in an
experiment?
A. To ensure that the sample represents the entire population
B. To eliminate the need for a control group
C. To reduce preexisting differences between experimental groups
D. To guarantee statistically significant findings
Answer: C. To reduce preexisting differences between experimental
groups
Rationale: Random assignment gives participants an approximately
equal chance of being placed into each experimental condition. This
helps distribute individual differences—such as intelligence,
motivation, and personality—across groups, making it more
reasonable to attribute differences in outcomes to the manipulated
independent variable. Random assignment is different from random
sampling, which concerns representativeness of the population.
3
, 6. In an experiment testing whether caffeine improves reaction time,
participants are randomly assigned to receive either caffeine or a
placebo. What is the independent variable?
A. Reaction time
B. Caffeine versus placebo condition
C. Participant age
D. Number of correct responses
Answer: B. Caffeine versus placebo condition
Rationale: The independent variable is the factor manipulated by the
researcher. Here, the researcher determines whether participants
receive caffeine or a placebo. Reaction time would be the dependent
variable because it is the outcome measured to determine whether the
manipulation produced an effect.
7. Which term refers to the measurable definition of a variable used
in a particular study?
A. Reliability
B. Operational definition
C. Replication
D. Randomization
Answer: B. Operational definition
Rationale: An operational definition specifies exactly how a
researcher will measure or manipulate a variable. For example,
instead of vaguely defining stress as “feeling pressured,” a researcher
might operationalize stress as a participant's score on a standardized
stress questionnaire or physiological measurement such as cortisol
level.
4
PSYCHOLOGY MIDTERM EXAM 2026
PRACTICE QUESTIONS WITH ANSWERS
ORIGINAL QUESTIONS, DETAILED
RATIONALES & STUDY GUIDE
1. Which statement best describes the primary goal of psychological
science?
A. To prove that human behavior is determined primarily by biology
B. To systematically describe, explain, predict, and influence behavior
and mental processes
C. To diagnose every unusual behavior as a psychological disorder
D. To eliminate subjective experiences from psychological research
Answer: B. To systematically describe, explain, predict, and
influence behavior and mental processes
Rationale: Psychology is a scientific discipline concerned with
understanding behavior and mental processes. Its goals traditionally
include describing what happens, explaining why it happens,
predicting when it may happen, and, when appropriate and ethical,
influencing or changing behavior. Psychology does not assume that
behavior is exclusively biological, nor does it define unusual behavior
automatically as pathological.
2. A researcher observes students in a university library without
interacting with them and records how often they use electronic
devices. Which research method is being used?
A. Naturalistic observation
B. Experimental manipulation
1
,C. Case study
D. Survey research
Answer: A. Naturalistic observation
Rationale: Naturalistic observation involves systematically observing
and recording behavior in its normal environment without directly
manipulating the situation. The researcher is not assigning students to
conditions or changing their environment. A survey would require
participants to provide self-reported information, while an experiment
would involve manipulation of an independent variable.
3. A psychologist wants to determine whether sleep deprivation
causes poorer memory performance. Which research design would
provide the strongest evidence for a causal relationship?
A. Correlational study
B. Case study
C. Controlled experiment
D. Naturalistic observation
Answer: C. Controlled experiment
Rationale: A controlled experiment allows researchers to manipulate
an independent variable—in this case, sleep deprivation—and
measure its effect on a dependent variable such as memory
performance. Random assignment and control over relevant variables
strengthen causal inference. Correlation can identify relationships but
cannot by itself establish causation.
4. A researcher finds that students who spend more hours studying
tend to earn higher exam scores. What does this finding
demonstrate?
2
,A. That studying definitely causes higher scores
B. A positive correlation between studying and exam performance
C. A negative correlation between studying and exam performance
D. That exam performance causes students to study more
Answer: B. A positive correlation between studying and exam
performance
Rationale: A positive correlation means that two variables tend to
increase or decrease together. Here, greater study time is associated
with higher exam scores. However, correlation alone cannot establish
causation because other factors—such as motivation, prior knowledge,
or time-management skills—could influence both variables.
5. What is the primary purpose of random assignment in an
experiment?
A. To ensure that the sample represents the entire population
B. To eliminate the need for a control group
C. To reduce preexisting differences between experimental groups
D. To guarantee statistically significant findings
Answer: C. To reduce preexisting differences between experimental
groups
Rationale: Random assignment gives participants an approximately
equal chance of being placed into each experimental condition. This
helps distribute individual differences—such as intelligence,
motivation, and personality—across groups, making it more
reasonable to attribute differences in outcomes to the manipulated
independent variable. Random assignment is different from random
sampling, which concerns representativeness of the population.
3
, 6. In an experiment testing whether caffeine improves reaction time,
participants are randomly assigned to receive either caffeine or a
placebo. What is the independent variable?
A. Reaction time
B. Caffeine versus placebo condition
C. Participant age
D. Number of correct responses
Answer: B. Caffeine versus placebo condition
Rationale: The independent variable is the factor manipulated by the
researcher. Here, the researcher determines whether participants
receive caffeine or a placebo. Reaction time would be the dependent
variable because it is the outcome measured to determine whether the
manipulation produced an effect.
7. Which term refers to the measurable definition of a variable used
in a particular study?
A. Reliability
B. Operational definition
C. Replication
D. Randomization
Answer: B. Operational definition
Rationale: An operational definition specifies exactly how a
researcher will measure or manipulate a variable. For example,
instead of vaguely defining stress as “feeling pressured,” a researcher
might operationalize stress as a participant's score on a standardized
stress questionnaire or physiological measurement such as cortisol
level.
4
