The Video Distortion Technique (VDT) scales all parts of the body ______. But with weight gain and loss the body does not change ______.
Define Weber's law.
Weber’s law states that the just noticeable difference (JND) between two stimuli will be a constant proportion of their magnitude, leading to a constant Weber fraction over the stimulus range (i.e. ΔI / I = K, where I = stimulus magnitude and K = constant)
In practice, what does Weber's law state regarding body judgement?
What does this mean for body estimation in anorexia?
A mass (body) must change by 5% to be noticed. Therefore larger bodies must change a lot more than smaller bodies to be noticeable:
- 5% of 100 = 5
- 5% of 20 = 1
This means that women with anorexia will tend to overestimate their body size and push them to get thinner, and they will be very sensitive to any increase to body size.
The most accurate way of judging peoples weight is by looking at their ______.
People’s ideal (not with eating disorder) is actually on the cusp of ______. This is quite worrying. People will say they do not want to be ______ but if they pick the ideal figure without knowing the corresponding BMI, the average pick is at this level.
Describe the adaptation effect.
VDT is used to show a scale of body sizes, asked people to guess which was the normal (average) size. They then did the same again but before asking showed a large body or a small body size. The results were the skewing of estimates based on what body size they saw first.
Define contraction bias.
A common response bias in psychophysical judgments is regression toward the mean (overestimation of small and underestimation of large values).
A body next to bigger bodies makes the body look ______. The same body next to ______ bodies makes the body look bigger.
When estimating BMI with morph, the area of body = ?
Perimeter : area ratio
Define perceptual distortion.
Person has difficulty accurately gauging body size. Eating-disordered individuals estimate their size as larger than is objectively true.
Define attitudinal distortion.
Patient may estimate size accurately, but is extremely dissatisfied with size, shape, or some other aspect of body appearance.