Backward masking occurs when the perception of a stimulus is attenuated by the rapid presentation of a subsequent stimulus (the “mask”). Within the domains of neuropsychology and psychology, backward masking typically refers to visual phenomena. However, backward masking has been explored in other sensory domains such as … (may want to list other domains here). In a typical backward masking paradigm, a visual stimulus (such as a letter) is rapidly presented and followed by a mask that encompasses the area of the visual field where the initial stimuli was presented (Breitmeyer and Ogmen 2000). The presentation of the initial stimulus, while rapid, is sufficiently long enough for a non-backward masked presentation to be perceptible. The mechanisms underlying backward masking are an active area of research; however, it is well established that central and likely cortical mechanisms are involved, given the time course of the effect as well as its ability to be produced with dichoptic presentation (stimulus and mask presented to separate eyes).
References and Readings
- Breitmeyer, B. G., & Ogmen, H. (2000). Recent models and findings in visual backward masking: a comparison, review, and update. Perception & Psychophysics, 62(8), 1572–1595. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/11140180