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Experimenter expectancy in resistance to respiratory air flow
Psychosomatic Medicine
|May 1, 1997
Summary
Experimenter expectations influenced respiratory resistance. Individuals perceived as likely to respond showed greater total respiratory resistance (Rt) increases when suggested breathing difficulty.
Area of Science:
- Psychology
- Physiology
- Medical Research
Background:
- Experimenter expectancy is a known bias in research.
- Previous studies have not fully explored its impact on physiological measures like respiratory resistance.
Purpose of the Study:
- To investigate the effect of experimenter expectancy on total respiratory resistance (Rt).
- To determine if perceived likelihood of response influences physiological reactions to suggestion.
Main Methods:
- Three naive experimenters collected respiratory air flow resistance data from 30 healthy subjects.
- Subjects were randomly assigned to groups based on experimenter's belief about their likelihood to respond to breathing difficulty suggestions.
Main Results:
- Subjects described as likely to respond exhibited significantly greater increases in total respiratory resistance (Rt).
- This occurred in response to suggestions of breathing difficulty compared to those described as unlikely to respond.
Conclusions:
- Experimenter expectancy introduces a significant source of variance in suggestion studies.
- This psychological factor must be considered in future research on physiological responses to suggestion.
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