PSYC 1010 Chapter Notes - Chapter 4: Optic Chiasm, Detection Theory, Subtractive Color

• School: York University
• Department: Psychology
• Course: PSYC 1010
• Professor: Agnieszka Kopinska

Document Summary

Jnd is the smallest difference in the amount of stimulation a specific sense can detect. Related to absolute threshold because it is jnd from nothing. Weber"s law: the size of jnd is proportional to size of stimulus; as stimuli increases, the jnd becomes larger. Fechner uses jnd to measure sensory experiences. Fechner"s law: the size of sensory experience is proportional to number of jnds the stimulus causes the experience above absolute threshold. Eg. going in a dark room turning on a light one by one. As stimulus intensity (amount of light) increases, sensation differences decreases (perceived brightness) Signal detection theory: detection of stimuli involves decision processes and sensory processes influenced by variety of factors besides stimulus intensity. Eg. reporting enemy aircraft; there are four possible outcomes such as hits, misses, false alarms and correct rejections. Retina: neural tissue in the inside back surface of the eye; it absorbs light, inputs images and sends visual information to the brain.