1. Analysis of a New Method for Studying Placebo Effects
Ryan A. Brabrand, Ryan E. Tracy, Niall A. Moreira, James J. Rossi M.A.,
Julian R. Keith Ph.D & Len B. Lecci Ph.D
University of North Carolina Wilmington
Brain Map & Treatment
Background
For the past 40 years, placebos have played an integral role in the medical field in helping to determine the efficacy of a variety of treatments (Barkley, 2006). This is accomplished by comparing a treatment group to the control (placebo) group.
The placebo effect occurs when an inert treatment produces beneficial results that should only be typical of a valid procedure and not a false treatment.
While the placebo effect is not yet fully explained, there are some plausible theories that may illuminate this phenomenon. Many learning theories help to explain that through pairing of traditional treatment (i.e. medicine, therapy, etc.) and the expectancy of the effectiveness of the treatment, an individual can induce the placebo effect and in turn show an improvement of symptoms (Klosterhalfen & Enck, 2012).
Placebos tend to be most effective when they feature elements such as a credible treatment medium, empathic concern, individualization of a treatment, perceived technical abilities of the health-care provider administering treatment, and tactile stimulation (Bootzin & Bailey, 2005)
Placebos have a neurological basis closely associated with the endogenous opioid system (Rossi, 2002)
Measures
Center for Epidemiological Studies Depression Scale (CES-D), (Radloff, 1977). A 20-item scale that measures depression in the general population.
Self Evaluation Questionnaire (SEQ), (Spielberger, 1968). A 20-item scale that measures state anxiety symptoms.
McGill Pain Questionnaire, (Melzack & Torgerson, 1971). A self-report questionnaire asking participants to indicate the intensity of their pain with 20 groups of various descriptors of pain intensity, as well as pain duration and previous experiences with pain.
Zung Self-Rating Anxiety Scale (SAS), (Zung, 1971). A 20-item self-report assessment measuring trait anxiety symptoms.
Kiddie Schedule for Affective Disorders and Schizophrenia (K-SADS), (Endicott & Spitzer, 1978). A modified version of the ADHD scale used to assess problems with attention.
Sham EEG brain mapping leads to “mild” brain activation.
“Bio-stimulation” leads to improved brain activation.
Results
To test the hypothesis that Bio-Stimulation treatment was an effective procedure for reducing pain, depression, anxiety and attention problems a series of 3x2 split plot Analyses of Variance (ANOVAs) were conducted with the between-subject variable being treatment group and the within-subjects variable being the time that the measure was filled out.
The dependent variable in each ANOVA was either a measure of depression, anxiety, pain or attention control.
For all analyses, no statistically significant between-subjects differences were detected.
For all analyses, no interaction effects were significant.
For depression, there was a significant reduction in symptoms F(2, 27) = 5.019, p = .014 with η2 = .271.
For anxiety as measured by the SEQ, there was a trend towards reduced symptoms F(2,27) = 2.982, p = .061 with η2 = .181.
For anxiety as measured by the SAS, there was a significant reduction of symptoms F(2,26) = , p < .001 with η2 = .444.
For attention control, there was a significant reduction of symptoms F(2,27) = 3.787, p = .036 with η2 = .219.
For pain, there was a significant reduction of symptoms F(2,27) = 4.455, p = .021 with η2 = .248.
Hypothesis
“Bio-stimulation” should produce significant reductions in depression, anxiety, attention control and pain at a follow up point. It is also expected that those believing they are in the active treatment group will report greater reductions in these symptoms. This is due to the nature of bio-stimulation taking advantage of characteristics of known placebo inducing effects.
Method
Participants
34 undergraduate students from University of North Carolina at Wilmington. 24 Female, 10 Male. Of which 22 Caucasian, 5 African American, 4 Hispanic, 1 Asian, 2 Other.
Procedure of “Bio-Stimulation”
Participants were administered pre treatment questionnaires consisting of depression, anxiety and pain scales.
A multimedia presentation was shown to introduce subjects to treatment.
Participants received a sham topographical EEG brain mapping.
Participants then received a fake “bio-stimulation” treatment to the same locations on their heads.
Participants were then told they were in either a placebo or active group for treatment and completed a set of post treatment questionnaires.
After approximately a week participants self-reported with the same measures as pre/post treatment since treatment was received.
Participants were then debriefed before leaving the study. Informed that no actual “bio-stimulation” was administered.
Personality & Demographics
Pre-Measures, EEG Map & Bio-Stimulation
Condition Reveal
Placebo Condition
Active Condition
Post Measures
Follow Up Measures One Week Post- Treatment & Debrief
Discussion
Initial investigation into the effectiveness of “bio-stimulation” reveals that the sham procedure actually reduces reported anxiety, depression, pain and attention control symptoms of subjects regardless of if the subject perceives themselves to be in the active or placebo treatment. This demonstrates the potential viability of “bio-stimulation” as a reliable and valid medium to produce placebo effects in a relatively healthy undergraduate sample.
Key features of “bio-stimulation” that may be responsible for producing the strong effects include: tactile stimulation, empathic concern, perceived expertise of treatment providers and a credible treatment setting.
Limitations of this study include a small sample size of non-clinical, college undergraduates which may limit external validity.
More research is needed to investigate personality and between-subjects effects.