Perception 1- Psychophysics Flashcards
What is psychophysics?
The relationship between subjective sensory experience and the objective physical stimuli that triggers this. Psychophysics are the methods by which we investigate this subjective individual experience.
What is psychometrics?
how we measure people’s subjective mental experience. It allows us to question the reliability, consistency and true reports of their internal experience
What is Stephen’s power law?
P=KS^n
P= perceived magnitude
S- Stimulus intensity
K,n- constants specific to perception
What is JND?
Just noticeable difference- the the smallest difference between two similar stimuli that can we can detect.
What is Webber’s Law?
Suggests that the JND is in constant proportion to the stimulus magnitude, regardless of the difference between size of stimuli, the JND will be the same.
△P/P = K p= stimulus intensity △P= JND K= Constant
What are the three classic methods of limits of perception/perceptual thresholds?
Method of limits, method of adjustment, method of constant stimuli
What is involved in the method of limits format of testing perception limits ?
We see if stimuli can be perceived at very low and very high magnitudes, turning it up each time, and using the report of the participant to judge when the stimulus is detected. However, this can create order effect
What is involved in the method of adjustment format of testing perception limits?
the participant starts at bassline and then adjusts the stimulus until they say they can detect it. This is the quickest method but is most dependent on participant cooperation
What is involved in the method of constant stimuli format of testing perception?
stimuli and stimulus intensity is preselected by the experimenter and the intensities are given in random order. We then plot when the stimuli is and isn’t detected to create a psychometric curve. This is the most precise but most time consuming method