Foundations Of Cognitive Science

Mental Scanning Task

A mental scanning task is an experimental technique that has been used to support the depictive theory of imagery proposed by Kosslyn (Kosslyn, 1980, 1994; Kosslyn, Thompson & Ganis, 2006). In a mental scanning task, subjects are asked to scan across a mental image and the latency of the scan is measured. For instance, in the famous map scanning experiment (Kosslyn, Ball, & Reiser, 1978), subjects learned to be able to generate a mental image of a map to a high degree of accuracy. The map depicted seven key locations on an island. In a test phase, subjects recalled the image, and were in essence asked to scan from one map location to another, indicating to the experimenter when the scan was complete. The basic result was a linear relationship between response latency and the distance scanned on the image. This was taken as evidence to support that one of the privileged properties of mental images was their spatial extent.


  1. Kosslyn, S. M. (1980). Image and Mind. Cambridge, MA: Harvard University Press.
  2. Kosslyn, S. M. (1994). Image and Brain. Cambridge, MA: MIT Press.
  3. Kosslyn, S. M., Ball, T. M., & Reiser, B. J. (1978). Visual images preserve metric spatial information: Evidence from studies of image scanning. Journal of Experimental Psychology: Human Perception and Performance, 4(1), 47-60.
  4. Kosslyn, S. M., Thompson, W. L., & Ganis, G. (2006). The Case For Mental Imagery. New York: Oxford University Press.

(Added September 2010)