Description: Prior research has reported that individual differences influence both placebo and nocebo responses. The present study examined how individual personality, as well as trust, influence placebo/nocebo belief and symptom reporting after receiving an inert capsule that for some was described as an active “cognitively-enhancing” trial medication. Individuals (N = 104) were randomly assigned to one of three conditions: condition A participants were told they’d received the medication, condition B participants were told they’d received a placebo, and condition C participants were told, via random assignment, each would receive either the medication or placebo (after the experiment this condition listed the group – medication or placebo - each believed s/he was in). The study was completed in the UNT Student Health and Wellness Center to provide context in a medical setting. Of the 104 participants, 46 (44.2%) were either placed by experimental design or self-report in the medication group. Participants with a belief in medication ingestion, regardless of condition (i.e., A or C), reported significantly more symptoms (M = 16.65, SD = 3.178), than participants who believed they had ingested a placebo (M = 14.21, SD = 2.58), t (102) = 4.32, p = .001. Aspects of Neuroticism and Extroversion, as well as trust were correlated with symptom reporting and/or placebo/nocebo responses. It appears that that personality is part of a combination including trust, context and expectations. It is recommended that future research on personality and placebo effects consider the role of individual factors, context and communication of expectations.
Date: August 2013
Creator: Baker, Brandon Wade Roger
Partner: UNT Libraries