Establishing Threshold for Visual Discrimination of Height in

Abstract

Human height is usually determined by objective measures. Taking into account that body height can have perceptual dimensions, it seems interesting to investigate this personal attribute by a more subjective approach. However, for this it would be former necessary to establish the capability to discriminate difference between figures depicturing body heights. Thus, the objective of this study was to establish the smallest perceptible difference whilst judging the similarity between different human figures representing body heights. Methods: 140 pairs of human figures were presented to 37 participants. The differences between human figures varied from 0 (equal) to 6 cm proportionally to the real height. Each participant judged whether the figures were similar or different. Results: The percentage of correct answers increased when the difference between figures increased. This percentage was higher than 70% for differences corresponding to 4 cm or higher of the real height for both genders. Conclusion: Relative difference (sensory threshold) of 4 cm was consistently established for visual discrimination of height in pictorial human body. This sensory threshold can be considered when studies on perceptual body height are conducted in the future.

Keywords: Psychophysics, Just Noticeable Difference, Human Figures, Sensory Threshold, Silhouettes

DOI: 10.54941/ahfe100809