Accession Number : ADA085737

Title :   A Pilot Study of Experimenter-Subject Effect on Dark Adaptation Thresholds.

Descriptive Note : Staff paper,

Corporate Author : HUMAN RESOURCES RESEARCH ORGANIZATION ALEXANDRIA VA

Personal Author(s) : Wright,Donald L.

Report Date : OCT 1969

Pagination or Media Count : 30

Abstract : To extend the findings of studies of experimenter-induced effect on research data to the area of sensory research, in which the experimenter often serves as his own subject (ES), a pilot study was designed to permit the operation of ES-induced bias during the collection of foveal dark adaptation data. An attempt was made to instil an expectancy in the ES before data collection, by acquainting him with the often-reported finding of a positive relationship between preadaptation duration (PD) and threshold elevation (TE) in dark adaptation. During the experiment, PD was frequently misrepresented as being longer or shorter than the actual PD. The data provided some support for the notion that expectancy of a positive relationship between PD and TE (apart from PD per se) may determine the elevation of the visual threshold in dark adaptation. But more of the data supported the post hoc notion that expectancy of a curvilinear relationship between PD and TE determined TE in this experiment. Reasons for inferring that this expectancy of a curvilinear relationship originated during data collection are discussed. (Author)

Descriptors :   *EXPERIMENTAL DATA, *BIAS, *DARK ADAPTATION, COMBAT EFFECTIVENESS, PERFORMANCE(HUMAN), TEST METHODS, HUMAN FACTORS ENGINEERING, PSYCHOLOGICAL TESTS, PILOT STUDIES.

Subject Categories : Psychology
      Test Facilities, Equipment and Methods
      Human Factors Engineering & Man Machine System

Distribution Statement : APPROVED FOR PUBLIC RELEASE