For many students, conducting an actual experiment may be outside the scope of their project or may not be permitted by their instructor, school, or institutional review board. If your assignment or projects requires you to conduct a true experiment that involves controlling and manipulating an independent variable, you will need to take care to choose a topic that will work within the guidelines of your assignment. Some of the psychology experiment or study ideas you might want to explore: Does sleep deprivation have an impact on short-term memory?
Ask participants how much sleep they got the night before and then conduct a task to test short-term memory for items on a list. Is social media usage linked to anxiety or depression?
Ask participants about how many hours week they use social media sites and then have them complete a depression and anxiety assessment. How does procrastination impact student stress levels? Ask participants about how frequently they procrastinate on their homework and then have them complete an assessment looking at their current stress levels.
How does caffeine impact performance on a Stroop test? In the Stroop test, participants are asked to tell the color of a word, rather than just reading the word. Have a control group consume no caffeine and then complete a Stroop test, and then have an experimental group consume caffeine before completing the same test.
Compare results. Does the color of text have any impact on memory? Randomly assign participants to two groups. Have one group memorize words written in black ink for two minutes.
Have the second group memorize the same words for the same amount of time, but instead written in red ink. Compare the results.
How does weight influence how people judge others? Find pictures of models in a magazine who look similar, including similar hair and clothing, but who differ in terms of weight. Have participants look at the two models and then ask them to identify which one they think is smarter, wealthier, kinder, and healthier. Assess how each model was rated and how her weight may have influenced how she was described by participants. Does music have an effect on how hard people work out?
Have people listen to different styles of music while jogging on a treadmill and measure their walking speed, heart rate, and workout length. How reliable is eyewitness testimony? Have participants view video footage of a car crash. If participants in the treatment condition end up better off than participants in the control condition—for example, they are less depressed, learn faster, conserve more, express less prejudice—then the researcher can conclude that the treatment works.
There are different types of control conditions. One problem with this approach, however, is the existence of placebo effects. Many folk remedies that seem to work—such as eating chicken soup for a cold or placing soap under the bedsheets to stop nighttime leg cramps—are probably nothing more than placebos. Figure 6. It could be instead that participants in the treatment group improved more because they expected to improve, while those in the no-treatment control condition did not.
Of course, the principle of informed consent requires that participants be told that they will be assigned to either a treatment or a placebo control condition—even though they cannot be told which until the experiment ends. In many cases the participants who had been in the control condition are then offered an opportunity to have the real treatment. This disclosure allows researchers to compare participants who have received the treatment with participants who are not currently receiving it but who still expect to improve eventually.
A final solution to the problem of placebo effects is to leave out the control condition completely and compare any new treatment with the best available alternative treatment.
For example, a new treatment for simple phobia could be compared with standard exposure therapy. Because participants in both conditions receive a treatment, their expectations about improvement should be similar. The Powerful PlaceboMany people are not surprised that placebos can have a positive effect on disorders that seem fundamentally psychological, including depression, anxiety, and insomnia.
However, placebos can also have a positive effect on disorders that most people think of as fundamentally physiological. Medical researcher J. Bruce Moseley and his colleagues conducted a study on the effectiveness of two arthroscopic surgery procedures for osteoarthritis of the knee Moseley et al.
The control participants in this study were prepped for surgery, received a tranquilizer, and even received three small incisions in their knees. But they did not receive the actual arthroscopic surgical procedure. The surprising result was that all participants improved in terms of both knee pain and function, and the sham surgery group improved just as much as the treatment groups.
Again, in a between-subjects experiment, one group of participants would be shown an attractive defendant and asked to judge his guilt, and another group of participants would be shown an unattractive defendant and asked to judge his guilt. The primary advantage of this approach is that it provides maximum control of extraneous participant variables. Participants in all conditions have the same mean IQ, same socioeconomic status, same number of siblings, and so on—because they are the very same people.
We will look more closely at this idea later in the book. However, not all experiments can use a within-subjects design nor would it be desirable to. Carryover Effects and Counterbalancing The primary disadvantage of within-subjects designs is that they can result in carryover effects.
Being tested in one condition can also change how participants perceive stimuli or interpret their task in later conditions.How reliable is eyewitness testimony? With counterbalancing, participants are assigned to orders randomly, using the techniques we have already discussed. The primary advantage of this approach is that it provides maximum control of extraneous participant variables. Make sure your hypothesis is testable with research and experimentation. The reference section at the back of your textbook can also serve as a great source for additional reference material. Medical researcher J. For example, if you have four treatments, you must have four versions. This conformity experiment investigates the impact of group pressure on individual behavior. Should college team players be treated as professional sportspeople be turned into an office-friendly one, too, you know.
Get together with a group of students in order to come up with a list of interesting ideas, subjects or questions. The teacher begins asking individual students in the room for the answer. For example: If I raise the temperature of a cup of water, then the amount of sugar that can be dissolved in it will be increased.
Talk to Your Instructor About Your Psychology Experiment Ideas Your professor or instructor is often the best person to consult for advice right from the start. When the teacher finally comes to you, do you trust your own math skills and say 32? This is not practical. State Your Case Scientists can really change the world with their hypotheses and findings. A final solution to the problem of placebo effects is to leave out the control condition completely and compare any new treatment with the best available alternative treatment. Give the participants a memory test a few days later and ask them to recall if they saw any broken glass at the scene of the accident.
Treatment and Control Conditions Between-subjects experiments are often used to determine whether a treatment works. Surely the alternative or experimental hypothesis is more important? Assess how each model was rated and how her weight may have influenced how she was described by participants. Finding a topic for your study can be difficult, but there are plenty of great ways to come up with intriguing ideas.
At this point, you might be asking why we seem so interested in the null hypothesis. Directional Hypothesis A one-tailed directional hypothesis predicts the nature of the effect of the independent variable on the dependent variable. Martin, D. Drinking sugary drinks daily leads to obesity. Medical researcher J.
Being tested in one condition can also change how participants perceive stimuli or interpret their task in later conditions.
A hypothesis is usually written in a form where it proposes that, if something is done, then something else will occur. A statistical hypothesis is an examination of a portion of a population. Randomly assign participants to two groups. An efficient way of counterbalancing is through a Latin square design which randomizes through having equal rows and columns. It states that the results are not due to chance and that they are significant in terms of supporting the theory being investigated. Compare test scores of students who ate breakfast to those who did not.
For example, I may want to drink root beer all day, not green tea. State your hypothesis as concisely, and to the point, as possible. The teacher begins asking individual students in the room for the answer. Write your hypothesis. Can certain colors improve learning?
Medical researcher J. Surely the alternative or experimental hypothesis is more important? You may need to get approval from your teacher or from an institutional review board before you begin. In your paper, you might opt to explore the typical duties of a psychologist, how much people working in these fields typically earn, and different employment options that are available. This usually involves proposing a possible relationship between two variables: the independent variable what the researcher changes and the dependent variable what the research measures.
In an attempt to disprove a null hypothesis, researchers will seek to discover an alternative hypothesis. A logical hypothesis is a proposed explanation possessing limited evidence. The surprising result was that all participants improved in terms of both knee pain and function, and the sham surgery group improved just as much as the treatment groups. Carryover Effects and Counterbalancing The primary disadvantage of within-subjects designs is that they can result in carryover effects. Have participants look at the two models and then ask them to identify which one they think is smarter, wealthier, kinder, and healthier. Ask participants about how frequently they procrastinate on their homework and then have them complete an assessment looking at their current stress levels.
Thus random assignment plays an important role in within-subjects designs just as in between-subjects designs. Usually, you don't want to state a hypothesis as a question. Can certain colors improve learning? Do people who use the social media site Facebook exhibit signs of addiction? Keep your language clean and simple.