Graduation Date
Summer 2025
Document Type
Thesis
Program
Master of Arts degree with a major in Psychology, option Academic Research
Committee Chair Name
Amanda Hahn
Committee Chair Affiliation
Cal Poly Humboldt Faculty or Staff
Second Committee Member Name
Carrie Aigner
Second Committee Member Affiliation
Cal Poly Humboldt Faculty or Staff
Third Committee Member Name
Julia Kandus
Third Committee Member Affiliation
Cal Poly Humboldt Faculty or Staff
Keywords
Cortisol, Placebo effect, Sing-a-song stress-test, Stress
Subject Categories
Psychology
Abstract
The placebo effect is well-studied on pain perception and is often observed to have a pain-reducing effect in patients. A few studies suggest that the placebo effect can influence physiological changes in people. To date, not many studies have examined the placebo effect on stress; thus, the current study explored the placebo effect on participants’ cortisol stress response and self-reported stress while undergoing a modified acute stress task, the Sing-a-Song Stress Test (SSST). The current study includes 44 participants (22 in the control group and 22 in the treatment group). A deceptive stress-reducing tincture (filled with water) was used as a placebo treatment along with a script that explained how it works. The current study did not find significant evidence that suggested the placebo effect can reduce people’s self-reported stress and salivary cortisol levels. It is important to note that the modified version of the SSST was not successful in inducing stress in participants. Therefore, the result should be interpreted with caution. Future researchers are recommended to further validate the SSST or use alternative stress-inducing paradigms that are well-validated, like the Tier Social Stress Test (TSST), to test similar hypotheses. Given the rise of mental health concerns and misuse of medication, similar hypotheses still need to be investigated, as they may provide new directions for developing treatments that incorporate the placebo effect, which may enhance the treatment outcome as well as reduce the unnecessary use of medications.
Citation Style
APA
Recommended Citation
Yam, Povheng, "Exploring the placebo effect on the cortisol stress response" (2025). Cal Poly Humboldt theses and projects. 2326.
https://digitalcommons.humboldt.edu/etd/2326
Included in
Behavioral Neurobiology Commons, Biological Psychology Commons, Health Psychology Commons, Physiology Commons