Using detection theory to analyze human decision making and sensory processing

On the 50th anniversary of the publication of Green and Swets’ book “Signal Detection Theory and Psychophysics,” it is fitting to revisit the question of how detection theory models of human decision making can improve our understanding of sensory processing. Classical psychophysics, as conceived by Fechner in 1850, trusts the observer to report sensory experiences without bias. The innovation of signal detection theory (SDT) was to develop methods that do not require the observer to have introspective awareness of internal sensations. Since its introduction, SDT has inspired experimentalists in many fields, and so now it is appropriate to simply refer to “detection theory” (DT) as the models are appropriate to a wide range of experiments, many of which do not involve signals in noise per se. Data from a previously published intensity discrimination task relying upon working memory (Gallun et al., 2012) will be examined in greater detail to show the techniques and benefits of a detection theory approach t...