PSYC 1001 Chapter Notes - Chapter 4: Detection Theory, Gustav Fechner, Absolute Threshold
Document Summary
Absolute threshold is the just noticeable difference from nothing. As stimuli increases in magnitude, the jnd becomes larger: psychological scaling. Fechner"s law states the magnitude of a sensory experience is proportional to the number of jnds that the stimulus causing the experience is above the absolute threshold. Constant increments in stimulus intensity produce smaller and smaller increases in perceived magnitude of sensation: ex. Turning 1 light bulb on in dark room causes big difference. Turning a second light bulb on causes a smaller increase in brightness and a third light bulb will cause an even smaller increase. Perception can"t be measured on absolute scales, with sensory experiences virtually everything is relative: signal detection theory. Signal detection theory proposes that the detection of stimuli involves decision processes as well as sensory as sensory processes, which are both influenced by a variety of factors besides stimulus intensity.
