Psychophysics Flashcards
why did Kant did not believe that psychology was a science?
- There is nothing to measure
- Subjective, not objective
- The act of introspection itself changes the content of the mind
Who was studying the JND? (Just noticeable difference)
Ernst Heinrich Weber
What is a Weber fractions?
It’s the fractions which are the JND between the standard and comparison weights is always close to 1/40 of the standard weight.
Are Weber fractions the same for each type of stimuli?
No
Discriminability
how easy it is to notice a small difference in therms of physical intensity.
Gustave Theodor Fechner
Mathematician, physicist and doctor.
Became blind after gazing too much at the sun while performing experiments.
Interested in the relationship between mind and matter.
“Fechner and Weber collaborated together and they noticed that ”Each JND is perceptually equivalent”.”
What does this mean?
The 1 gram difference between 40 and 41 grams is exactly as perceptually salient as the 10
gram difference between 410 and 400 grams
What is referred to as a perceptual
”atom”? And why?
Perceptual atom is the JND since it is the smallest noticeable different and can’t be further fragmented.
What is Fechner’s formula?
S = klog(R)
