Decision Making, Perceptual

One can define perceptual decision making (PDM) as a categorical choice based on sensory information. For example, did you just hear an airplane flying by or was it a helicopter? PDM can be contrasted with economic, emotional, reward-based, or value-based decision making, in which the decision is driven by the desirability of an option. For example, you see two identical-looking boxes in front of you. From past experience, you know that you are less likely to find candy when opening the right box. You therefore choose the left box. Because perceptual decisions can only be studied when the choice is reported by the subject, studies of PDM usually also involve a verbal report or triggering an action (pushing a button, for example).

Perceptual decisions can be classified based on their complexity. The simplest type of perceptual decision is deciding whether a stimulus has been present or not (stimulus detection). “Did you perceive a flash of light?” would be an example. More complex perceptual decisions involve making a choice between two categories (binary choice). Examples would be “Did you see a cat or a dog?,” “Was the second tone louder or softer than the first one?,” or “Did you feel a touch on your left or on your right arm?” Even more complex perceptual decisions involve choices between multiple categories (for example, “In which of the four cardinal directions was the object moving?”).

The goal of studying PDM is to understand how humans and animals process sensory information for categorizing stimuli and triggering appropriate actions. This involves understanding the choice behavior itself as well as the neural mechanisms leading to this choice behavior. Traditionally, PDM has been studied primarily by psychophysicists and (mathematical) psychologists, but more recently, it has also become a popular area of research in neu-roscience. Interdisciplinary approaches that combine behavioral and physiological experimental techniques with mathematical modeling are aimed at understanding the mathematical algorithms underlying PDM (the “recipes” for how to come up with an appropriate choice) as well as their neural implementation (how these computations are performed by the brain).

This entry first summarizes behavioral aspects of PDM, continues with a discussion of neural correlates, and finishes with a review of theoretical concepts.