Beat the Bots: Exploring the Effects of Placebo Manipulation on Performance During Video Gameplay

This study investigates placebos and video games’ usefulness as psychological research tools. One proposed underlying mechanism of the placebo effect is participants’ expectations. Such expectation effects exist in sports psychology and healthcare domains, but inconsistent findings have emerged on whether similar effects impact a participants’ cognitive performance. Concurrently, using video games as task environments is an emerging methodology relating to expertise and large-scale behavioral data collection. Therefore, this study examines the expectancy effect induced by researcher instructions on in-game performance. The instructional expectancy condition for this study is in-game successes framed using emoting (e.g., emoting under the pretense of subsequent performance increases) versus a control group. Preliminary results showed no evidence of different in-game performance between expectancy conditions. Potential mechanisms that could have led to a lack of effect were discussed.

Evaluating cannabidiol (CBD) expectancy effects on acute stress and anxiety in healthy adults: a randomized crossover study

Rationale Cannabidiol (CBD) has been reported to attenuate stress and anxiety, but little is known about the extent to which such effects result from pharmacological versus expectancy factors. Objectives We evaluated whether CBD expectancy alone could influence stress, anxiety, and mood, and the extent to which beliefs regarding CBD effects predicted these responses. Methods In this randomized crossover study, 43 health adults (23 women) attended two experimental laboratory sessions, where they self-administered CBD-free hempseed oil sublingually. During one session, they were (incorrectly) informed that the oil contained CBD and in the other session, that the oil was CBD-free. Following administration, participants engaged in the Maastricht Acute Stress Test (MAST). Heart rate variability (HRV) was assessed continuously, and subjective state was assessed at baseline, 90-min following oil administration, immediately following the MAST, and after a 10-min recovery period. Results The CBD expectancy condition was associated with increased sedation as well as with changes in HRV that were consistent with heightened anticipatory stress regulation. Overall, there were no systematic changes in subjective stress, or anxiety, according to expectancy condition. However, participants who endorsed strong a priori beliefs that CBD has anxiolytic properties reported significantly diminished anxiety in the CBD expectancy condition. Conclusions CBD expectancy alone impacted several subjective and physiological responses. Additionally, expectancy-related factors were implicated in anxiolytic effects of CBD for those who believed it was helpful for such purposes, emphasizing the need to measure and control for CBD-related expectancies in clinical research that involves the administration of CBD.

“I Wouldn't Have Seen it If I Hadn't Believed it”

38 students enrolled in an introductory special education class in education of the emotionally disturbed were randomly assigned to two treatment conditions, a normal (control) condition and low expectancy condition. These teacher trainees participated in a two phase study. During phase 1 the teachers were asked to rate a hypothetical normal child (control group) or a hypothetical emotionally disturbed child (low expectancy group) on two dependent measures developed for this research. During phase 2, both groups independently viewed a videotape of the same normal child. The control group was told the child was normal; the low expectancy group was told the child was emotionally disturbed. Both groups completed the same dependent measures following observation of the child. Differences between the groups in both phases indicate that teacher trainees hold negative stereotypical expectations of children labeled emotionally disturbed. Observations of normal behavior alter these expectations to some extent, but the negative halo of the label still results in more negative perceptions of behavior than when the child is labeled normal.

Psychology of the Scientist: X. Observer Bias in Classical Conditioning of the Planarian

Three groups of undergraduate volunteers were given differential expectancies about S's behavior prior to their observations of planaria undergoing conditioning. Group HE ( n = 5) received a high response expectancy, Group LE ( n = 5) a low response expectancy, and Group HLE observed one planarian under each expectancy condition. Group HE reported 18% contractions and 49% head turns in 100 trials whereas Group LE reported but 9% and 9.9%. Group HLE reported 15.4% contractions and 30% head turns under high expectancy instructions, but only 4.8% and 15.4% under low expectancy instructions. Analyses of the effect of instructions between Groups HE and LE and within Group HLE both yielded significant F ratios ( P < .001). Although it is unwise to generalize from naive volunteers to sophisticated investigators, it is clear that response recording in planaria should be made less ambiguous, perhaps by taking photographic records.