Psychology 1000 Lecture Notes - Lecture 13: Subliminal Stimuli, Retina, Power Law

• School: Western University
• Department: Psychology
• Course: Psychology 1000
• Professor: Dr.Mike

Document Summary

Relationship between physical stimulus and psychological response. Can determine a just noticeable difference (jnd) Change something and measure how they notice a difference. Value of a stimulus characteristic required to produce some response. Tsp. of sugar in 8l of water. 1 drop of perfume in a 6 room apartment. Wing of a fly falling on your cheek at a distance. Difference threshold of 1 cm: amount of change necessary for a jnd, ex. Doubling light in a room doesn"t make it twice as bright for a person perceiving it: weber"s law. Size of difference threshold relative to physical intensity of test is constant ( change in intensity (i) / i = constant. If i is 50 db, and a jnd is reported at 55 db. Would be 5/50 therefore 1/10: can predict other jnd at other intensities. 1/10 = change in i / 100. Therefore jnd will occur at 110 or 90 if test is at 100.