PS101 Lecture Notes - Lecture 4: Simple Cell, Receptive Field, Optical Illusion
Document Summary
Absolute threshold: minimum amount of stimulation an organism can detect. 50% of the time: repeatedly present a stimulus, if you perceive it 50% of the time, that"s you"re a. t, why is it just 50% of the time. Just noticeable diference: smallest detectable diference in the amount of stimulation: governed by weber"s law (jnd is a constant proportion of the size of the initial stimulus) What is the smallest amount you"ll notice if something changes. The larger stimulus , the larger the change has to be to notice it. Fechner"s law: how much you perceive is a function of # jnds above absolute threshold: the further above you are from you"re a. t, the harder it is to perceive change. Signal detection theory: detection involves sensation and decision: sensation. Motivations: problem with measuring sensation occur when we forget about peoples motivation. Ex when you pinch someone their reaction is ouch : the bias are accounted for when we calculate thresholds.
