The Impact of Nocebo and Placebo Effects on Reported Incidience of Actute Mountain Sickness

2021 ◽  
Author(s):  
Peter Bärtsch
Keyword(s):  
Placebo Effects ◽  
Mountain Sickness ◽  
The Impact

scholarly journals How Can Acute Mountain Sickness be Quantified at Moderate Altitude?

1996 ◽  
Vol 89 (3) ◽  
pp. 141-143 ◽  
Author(s):  
G Roeggla ◽  
M Roeggla ◽  
A Podolsky ◽  
A Wagner ◽  
A N Laggner
Keyword(s):  
Physical Examination ◽  
Oxygen Saturation ◽  
Gold Standard ◽  
Acute Mountain Sickness ◽  
Structured Interview ◽  
Moderate Altitude ◽  
Investigation Methods ◽  
Wide Variability ◽  
Mountain Sickness ◽  
The Impact

Reports of acute mountain sickness (AMS) at moderate altitude show a wide variability, possibly because of different investigation methods. The aim of our study was to investigate the impact of investigation methods on AMS incidence. Hackett's established AMS score (a structured interview and physical examination), the new Lake Louise AMS score (a self-reported questionnaire) and oxygen saturation were determined in 99 alpinists after ascent to 2.94 km altitude. AMS incidence was 8% in Hackett's AMS score and 25% in the Lake Louise AMS score. Oxygen saturation correlated inversely with Hackett's AMS score with no significant correlation with the Lake Louise AMS score. At moderate altitude, the new Lake Louise AMS score overestimates AMS incidence considerably. Hackett's AMS score remains the gold standard for evaluating AMS incidence.

“Because I know It will!”: Placebo Effects of an Ergogenic Aid on Athletic Performance

2007 ◽  
Vol 29 (3) ◽  
pp. 382-394 ◽  
Author(s):  
Mary McClung ◽  
Dave Collins
Keyword(s):  
Drug Use ◽  
Sodium Bicarbonate ◽  
Athletic Performance ◽  
High Performance ◽  
Ergogenic Aids ◽  
Placebo Effects ◽  
Expectancy Effects ◽  
Diverse Range ◽  
Significant Performance ◽  
The Impact

In the perpetual quest for better performance, athletes are using an increasingly diverse range of ergogenic aids. Some are permitted; however, this “drug” use is often seen as an ethically questionable behavior. A variety of research suggests that much of the impact of such aids may be due to expectancy—the belief that the substance will aid performance. It would be useful to demonstrate this to athletes considering such usage, especially as a pillar of antidrug education. Accordingly, this investigation used sodium bicarbonate and placebo additives in a double disassociation design, with athletes completing a series of 1,000-m time trials. Results showed that believing one had taken the substance resulted in times almost as fast as those associated with consuming the drug itself. In contrast, taking the drug without knowledge yielded no significant performance increment. Results are discussed against the backdrop of applying expectancy effects in high-performance sport, including dissuading athletes from using illegal aids.

scholarly journals Hypercapnic ventilatory response is decreased in a mouse model of excessive erythrocytosis

2016 ◽  
Vol 311 (5) ◽  
pp. R940-R947
Author(s):  
Sofien Laouafa ◽  
Elizabeth Elliot-Portal ◽  
Susana Revollo ◽  
Edith M. Schneider Gasser ◽  
Vincent Joseph ◽  
...  
Keyword(s):  
Ventilatory Response ◽  
Serum Levels ◽  
Metabolic Effect ◽  
Chronic Mountain Sickness ◽  
Central Chemosensitivity ◽  
Hypercapnic Ventilatory Response ◽  
Intracisternal Injection ◽  
Key Factor ◽  
Mountain Sickness ◽  
The Impact

The impact of cerebral erythropoietin (Epo) in the regulation of the hypercapnic ventilatory response (HcVR) is controversial. While we reported that cerebral Epo does not affect the central chemosensitivity in C57Bl6 mice receiving an intracisternal injection of sEpoR (the endogenous antagonist of Epo), a recent study in transgenic mice with constitutive high levels of human Epo in brain and circulation (Tg6) and in brain only (Tg21), showed that Epo blunts the HcVR, maybe by interacting with central and peripheral chemoreceptors. High Epo serum levels in Tg6 mice lead to excessive erythrocytosis (hematocrit ~80–90%), the main symptom of chronic mountain sickness (CMS). These latter results support the hypothesis that reduced central chemosensitivity accounts for the hypoventilation observed in CMS patients. To solve this intriguing divergence, we reevaluate HcVR in Tg6 and Tg21 mouse lines, by assessing the metabolic rate [O consumption (V̇) and CO production (V̇)], a key factor modulating ventilation, the effect of which was not considered in the previous study. Our results showed that the decreased HcVR observed in Tg6 mice (~70% reduction; < 0.01) was due to a significant decrease in the metabolism (~40%; < 0.0001) rather than Epo’s effect on CO chemosensitivity. Additional analysis in Tg21 mice did not reveal differences of HcVR or metabolism. We concluded that cerebral Epo does not modulate the central chemosensitivity system, and that a metabolic effect upon CO inhalation is responsible for decreased HcVR observed in Tg6 animals. As CMS patients also show decreased HcVR, our findings might help to better understand respiratory disorders at high altitude.

scholarly journals Expectancy effects threaten the inferential validity of synchrony-prosociality research

2020 ◽  
Author(s):  
S. Atwood ◽  
Samuel A Mehr ◽  
Adena Schachner
Keyword(s):  
A Priori ◽  
Large Body ◽  
Placebo Effects ◽  
Expectancy Effects ◽  
Original Experiment ◽  
Prosocial Attitudes ◽  
Experimenter Expectancy ◽  
And Behavior ◽  
Attitudes And Behavior ◽  
The Impact

A large body of theoretical and experimental work has argued that synchronized movement among people increases prosocial attitudes and behavior. Here we review prior and new evidence that reported effects of synchrony may be driven by experimenter expectancy, leading to experimenter bias; and participant expectancy, otherwise known as placebo effects. To test for the possibility of placebo effects, we asked whether participants have a priori expectations about synchrony and prosociality that match the findings in published literature. In a preregistered experiment, we asked undergraduates (N = 216) to imagine they participated in a synchrony experiment and then predict how they would feel and act afterward. The imagined experiment and the measures of their feelings and actions were taken from a highly cited experiment on synchrony. Even without experiencing an actual synchrony manipulation, participants’ expectations about the effects of synchrony on prosocial attitudes closely matched the actual effects of synchrony reported in the original experiment. The participants who imagined synchronizing expected to feel greater levels of connection, trust, same team feeling, and similarity to their partner, but not greater happiness, than the participants who imagined action that was not synchronized. These expectations (both positive and null) directly mirror reported effects of synchrony, raising the possibility that the synchrony-prosociality literature is vulnerable to placebo effects. Previously reported effects may reflect participants’ top-down expectations about synchrony, rather than the impact of experience with synchrony itself.

Psychobiological Mechanisms of Placebo and Nocebo Effects: Pathways to Improve Treatments and Reduce Side Effects

2019 ◽  
Vol 70 (1) ◽  
pp. 599-625 ◽  
Author(s):  
Keith J. Petrie ◽  
Winfried Rief
Keyword(s):  
Side Effects ◽  
Treatment Success ◽  
Significant Proportion ◽  
Future Research ◽  
Placebo Effects ◽  
Nocebo Effect ◽  
Medical Interventions ◽  
Nocebo Effects ◽  
The Impact ◽  
Improve Clinical Outcome

Placebo effects constitute a major part of treatment success in medical interventions. The nocebo effect also has a major impact, as it accounts for a significant proportion of the reported side effects for many treatments. Historically, clinical trials have aimed to reduce placebo effects; however, currently, there is interest in optimizing placebo effects to improve existing treatments and in examining ways to minimize nocebo effects to improve clinical outcome. To achieve these aims, a better understanding of the psychological and neurobiological mechanisms of the placebo and nocebo response is required. This review discusses the impact of the placebo and nocebo response in health care. We also examine the mechanisms involved in the placebo and nocebo effects, including the central mechanism of expectations. Finally, we examine ways to enhance placebo effects and reduce the impact of the nocebo response in clinical practice and suggest areas for future research.

scholarly journals Adaptation of ghrelin and the GH/IGF axis to high altitude

2012 ◽  
Vol 166 (6) ◽  
pp. 969-976 ◽  
Author(s):  
Stefan Riedl ◽  
Michael Kluge ◽  
Katharina Schweitzer ◽  
Thomas Waldhör ◽  
Herwig Frisch
Keyword(s):  
High Altitude ◽  
Acute Mountain Sickness ◽  
Well Being ◽  
Metabolic Effects ◽  
Igf Binding Proteins ◽  
Adaptive Processes ◽  
Igf Binding ◽  
Acid Labile Subunit ◽  
Mountain Sickness ◽  
The Impact

ObjectiveHigh altitude (HA) provokes a variety of endocrine adaptive processes. We investigated the impact of HA on ghrelin levels and the GH/IGF axis.DesignObservational study as part of a medical multidisciplinary project in a mountainous environment.MethodsThirty-three probands (12 females) were investigated at three timepoints during ascent to HA (A: d −42, 120 m; B: d +4, 3440 m; C: d +14, 5050 m). The following parameters were obtained: ghrelin; GH; GH-binding protein (GHBP); IGF1; IGF2; IGF-binding proteins (IGFBPs) -1, -2, and -3; acid-labile subunit (ALS); and insulin. Weight was monitored and general well being assessed using the Lake Louise acute mountain sickness (AMS) score.ResultsGhrelin (150 vs 111 pg/ml;P<0.01) and GH (3.4 vs 1.7 μg/l;P<0.01) were significantly higher at timepoint C compared with A whereas GHBP, IGF1, IGF2, IGFBP3, ALS, and insulin levels did not change. IGFBP1 (58 vs 47 μg/l;P<0.05) and, even more pronounced, IGFBP2 (1141 vs 615 μg/l;P<0.001) increased significantly. No correlation, neither sex-specific nor in the total group, between individual weight loss (females: −2.1 kg; males: −5.1 kg) and rise in ghrelin was found. Five of the subjects did not reach investigation point C due to AMS.ConclusionsAfter 14 days of exposure to HA, we observed a significant ghrelin and GH increase without changes in GHBP, IGF1, IGF2, IGFBP3, ALS, and insulin. Higher GH seems to be needed for acute metabolic effects rather than IGF/IGFBP3 generation. Increased IGFBP1 and -2 may reflect effects from HA on IGF bioavailability.

Cognitive Therapy with Aged Persons: Implications of Research Design for Its Implementation and Evaluation

1989 ◽  
Vol 3 (4) ◽  
pp. 255-271 ◽  
Author(s):  
Bert Hayslip ◽  
Marsha L. Caraway
Keyword(s):  
Cognitive Therapy ◽  
Research Design ◽  
Older Persons ◽  
Elderly Persons ◽  
Placebo Effects ◽  
Rational Solutions ◽  
Environmental Support ◽  
Cognitive Interventions ◽  
Everyday Problems ◽  
The Impact

On the basis of intervention research with elderly persons, numerous research design issues are discussed that influence the implementation and evaluation of cognitive therapy with aged individuals. These issues reflect a concern for the impact of placebo effects, sampling, and attrition on treatment efficacy, as well as attention to the measurement of rational thinking in the aged. Moreover, environmental support for rational solutions to everyday problems among older persons may vary. It is argued that given the limited research to date, an awareness of such issues must temper conclusions about the effectiveness of cognitive interventions with older persons.

Formation of Lunar Craters and Bright Rays as a Result of Meteorite Impacts

1962 ◽  
Vol 14 ◽  
pp. 415-418
Author(s):  
K. P. Stanyukovich ◽  
V. A. Bronshten
Keyword(s):  
Explosive Charge ◽  
The Moon ◽  
Meteorite Impacts ◽  
The Earth ◽  
Lunar Craters ◽  
The Impact

The phenomena accompanying the impact of large meteorites on the surface of the Moon or of the Earth can be examined on the basis of the theory of explosive phenomena if we assume that, instead of an exploding meteorite moving inside the rock, we have an explosive charge (equivalent in energy), situated at a certain distance under the surface.

The Geosciences Applied to Lunar Exploration

1962 ◽  
Vol 14 ◽  
pp. 169-257 ◽  
Author(s):  
J. Green
Keyword(s):  
Lunar Surface ◽  
Probable Mechanism ◽  
Point Of View ◽  
Lunar Exploration ◽  
Geological Model ◽  
Apply Geophysics ◽  
Surface Features ◽  
The Impact

The term geo-sciences has been used here to include the disciplines geology, geophysics and geochemistry. However, in order to apply geophysics and geochemistry effectively one must begin with a geological model. Therefore, the science of geology should be used as the basis for lunar exploration. From an astronomical point of view, a lunar terrain heavily impacted with meteors appears the more reasonable; although from a geological standpoint, volcanism seems the more probable mechanism. A surface liberally marked with volcanic features has been advocated by such geologists as Bülow, Dana, Suess, von Wolff, Shaler, Spurr, and Kuno. In this paper, both the impact and volcanic hypotheses are considered in the application of the geo-sciences to manned lunar exploration. However, more emphasis is placed on the volcanic, or more correctly the defluidization, hypothesis to account for lunar surface features.

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