What Is the Experimental Method in Psychology?
The experimental method involves manipulating one variable to determine if this causes changes in another variable.
This method relies on controlled research methods andrandom assignmentof study subjects to test a hypothesis.
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For example, researchers may want to learn how different visual patterns may impact our perception.
Or they might wonder whether certain actions canimprove memory.
Positivism is also important in the experimental method.
It refers to factual knowledge that is obtained through observation, which is considered to be trustworthy.
When using the experimental method, researchers first identify and define key variables.
Then they formulate a hypothesis, manipulate the variables, and collect data on the results.
Unrelated or irrelevant variables are carefully controlled to minimize the potential impact on the experiment outcome.
Wilhelm Wundt established the first formal laboratory in 1879.
Wundt is often called the father of experimental psychology.
He believed that experiments could help explain how psychology works, and used this approach to studyconsciousness.
Wundt coined the term “physiological psychology.
“This is a hybrid of physiology and psychology, or how the body affects the brain.
Dependent Variable
Thedependent variableis the effect that the experimenter is measuring.
Independent Variable
Theindependent variableis the variable that the experimenter manipulates.
In the previous example, the amount of sleep an individual gets would be the independent variable.
Hypothesis
Ahypothesisis a tentative statement or a guess about the possible relationship between two or more variables.
The purpose of the experiment, then, is to either support or reject this hypothesis.
Operational definitions are necessary when performing an experiment.
Extraneous Variables
Extraneous variables are other variables that may also affect the outcome of an experiment.
Types of extraneous variables include participant variables, situational variables, demand characteristics, and experimenter effects.
In some cases, researchers can take steps to control for extraneous variables.
This can sometimes cause participants to alter their behavior, which can affect the results of the experiment.
Intervening Variables
Intervening variables are factors that can affect the relationship between two other variables.
The Experimental Process
Psychologists, like other scientists, use the scientific method when conducting an experiment.
Learninghow to conduct an experimentis important to understanding how psychologists prove and disprove theories in this field.
Field Experiments
Sometimes researchers opt to conduct their experiments in the field.
This throw in of experiment can be a great way to see behavioral responses in realistic options.
Quasi-Experiments
While lab experiments are known as true experiments, researchers can also utilize a quasi-experiment.
Participants also cannot be randomly assigned because they naturally fall intopre-existing groupsbased on their birth order.
So why would a researcher use a quasi-experiment?
This is a good choice in situations where scientists are interested in studying phenomena in natural, real-world configs.
It’s also beneficial if there are limits on research funds or time.
Field experiments can be either quasi-experiments or true experiments.
It found thatdividing attentionbetween these two mediums did not affect lecture comprehension.
However, it did impact long-term retention of the lecture information, which affected students' exam performance.
It found that the effects were the same in both cases.
Memory
One experimental study evaluated whether exercise timing impacts information recall.
It found that engaging in exercise prior to performing a memory task helped improve participants’short-term memoryabilities.
Perception
Sometimes researchers use the experimental method to get a bigger-picture view of psychological behaviors and impacts.
Sensation
A 2020 study set out to determine the role thatsensation-seekingplays in political violence.
This research found that sensation-seeking individuals have a higher propensity for engaging in political violence.
Experiments may produce artificial results, which are difficult to apply to real-world situations.
Similarly, researcher bias can impact the data collected.
Results may not be able to be reproduced, meaning the results havelow reliability.
In addition, political pressure may alter the results.
The subjects may not be a good representation of the population, or groups used may not be comparable.
And finally, since researchers are human too, results may be degraded due to human error.
What This Means For You
Every psychological research method has its pros and cons.
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