The misinformation effect is a memory bias that occurs when misinformation affects people's reports of their own memory.

In one oft-cited study led by Elizabeth Loftus, people watched footage of a car accident. Later some were asked to estimate the speed at which the car was going when it hit the other car. Others were asked how fast they thought the car was going when it smashed into the other. Those who were asked the question with the smashed wording were much more likely to "remember" seeing broken glass in a later question (in reality, no glass had been broken in the accident). They also remembered the car as driving much faster.

Another type of misformation that appears to affect memory can come in the form of false presuppositions, such as "Did the car stop at the stop sign?" when in fact it was a yield sign .

The effect serves as an illustration of the assertion that many psychologists make about memory, that it is "constructed" on the fly rather than "played back" like a video tape, and it can apparently be influenced by suggestive wording.

In a more recent study, researchers led by Henry Roediger used this effect in conjunction with the method of the Asch conformity experiments: two participants were asked to recall information about a scene, one of whom was a confederate who gave intentionally inaccurate information. In this case, the "real" subject were likely to remember seeing things that the confederate had also reported (but which did not occur).

See also

• priming
• presupposition
• false memory
• list of cognitive biases

References

• Loftus, E. F. & Palmer, J. C. (1974). Reconstruction of automobile destruction. Journal of Verbal Learning and Verbal Behaviour, 13, 585-589. Full Text (PDF). Summary here and here.
• Loftus, E. F. (1993). Made in memory: Distortions in memory after misleading communications. In D. L. Medin (Ed.), The psychology of learning and motivation: Advances in research and theory Vol. 30, pp. 187-215. San Diego: Academic Press.
• Roediger, H.L., Meade, M.L. & Bergman, E. (2001) . Social contagion of memory. Psychonomic Bulletin & Review, 8, 365-371. Full Text (PDF).