How do perception and sensation influence behavior?

13.05.2016 10:35

Psychology: The Power of Expectations

Robert Emmerich Press and public relations
Julius Maximilians University of Würzburg

“You are much less sensitive to pain than others!” Those who get this insurance can endure pain better afterwards. The extent to which expectations can have an impact is being researched at the Department of Psychology.

Expectations have great power over people. This is shown very nicely by the placebo effect: a patient is given pills that do not contain any active substance. But the patient does not know that. He firmly believes that he will be given an effective drug - and his illness will actually improve. This was solely due to his expectations.

"The placebo effect often works very well in treating pain and depression," says Dr. Katharina Schwarz from the Institute for Psychology at the University of Würzburg. The pure expectation of receiving a drug can alleviate symptoms and improve well-being: "And that is not only a subjective sensation of the patient, but can also be measured physiologically."

Expectations change the perception of pain

Katharina Schwarz generally deals with the influence expectations have on perception and behavior. In her doctoral thesis, which she completed in 2015 at the University Medical Center Hamburg-Eppendorf, pain also played a role. One result: if men are given to understand that they are more sensitive or less sensitive than women, then their perception of pain changes.

The experiment: The participants of the experiment were given various heat stimuli with a strap on their forearms. They had to rate the pain felt in each case on a scale from “no pain” to “unbearable”.

On the next day of the experiment, the men were casually informed on an information sheet that they were either less sensitive or more sensitive to pain than women. This was justified by evolutionary psychology: a test group received the information that men, for example as hunters, are particularly used to pain. The other group read that women were particularly toughened by the pain of childbirth.

The experiment was then repeated. Now the test subjects, who considered men to be less sensitive, rated the pain as significantly less than the day before. Those who, on the other hand, had read about the higher pain tolerance of women now classified themselves as more sensitive to pain than before.

Review article published on the topic

Katharina Schwarz is currently showing in a review article in the specialist journal "Trends in Cognitive Sciences" how far the influence of expectations can go on people. For the first time, she puts examples from a wide variety of disciplines into context: “The neurosciences, psychology and pedagogy deal with expectations and their effects. But the individual disciplines hardly exchange information and I would like to change that. "

Her goal: "Above all, I would like to increase the students' awareness of these mechanisms, especially those that have a negative effect on people." This is of practical importance not only for therapies, but also in psychological research: "Also Scientists have certain expectations in their work. If you incorporate this into the test design and influence the test subjects accordingly - without any bad intentions - the results can be falsified. "

Keeping an eye on non-explicit expectations

At the University of Würzburg, Katharina Schwarz wants to advance this field of research and also increasingly deal with non-explicit expectation processes - this means expectations that people have but are not aware of.

Katharina Schwarz has been researching as a postdoc at the chair of the Würzburg psychology professor Wilfried Kunde since autumn 2015. She was born and raised in Würzburg and studied biology here. After graduation, she went on to do a doctorate in cognitive neuroscience at the University Medical Center Hamburg-Eppendorf.

Schwarz, K. A., Pfister, R., & Büchel, C. (in press). Rethinking explicit expectations: Connecting placebos, social cognition, and contextual perception. Trends in Cognitive Sciences. doi: 10.1016 / j.tics.2016.04.001


Dr. Katharina Schwarz, Chair of Psychology III, University of Würzburg, T (0931) 31-88655, [email protected]

Additional Information: To the website of Katharina Schwarz

Features of this press release:
Journalists, everyone
Society, pedagogy / education, psychology
Research results, scientific publications