What Is the Misinformation Effect?

The misinformation effect is the tendency for the information you learned after an event to interfere with your original memory of what happened. Research has shown that introducing even relatively subtle new information later on can dramatically affect how people remember events they have seen or experienced.

The misinformation effect illustrates how easily memories can be influenced. It also raises concerns about the reliability of memory—particularly when the memories of eyewitnesses are used to determine criminal guilt, referred to as eyewitness testimony. 

What Is the Misinformation Effect?

The misinformation effect refers to a type of memory impairment caused by the introduction of misleading information. Essentially, the misleading information becomes incorporated into the memory of the past event.

The work of psychologist Elizabeth Loftus and her colleagues has demonstrated that the questions asked after witnessing an event can influence a person's memory of that event. In other words, if a question contains misleading information, it can distort the memory of the event, a phenomenon that psychologists have dubbed "the misinformation effect." 

Misinformation Effect Example

An example of the misinformation effect could be a person who had witnessed a car accident on their way home from work. When they later hear a news report stating that the driver was speeding, they might later add that detail to their recollection of the event, even if that wasn't what actually happened.

Example of the Misinformation Effect in Psychology Research

In the famous experiment conducted by Loftus, participants were shown video footage of a traffic accident. After watching the clip, participants were asked a number of questions about what they had observed, much in the same way police officers, accident investigators, and attorneys might question an eyewitness.

One of the questions asked was, "How fast were the cars going when they hit each other?" In some instances, however, a subtle change was made; participants were instead asked how fast the cars were going when they "smashed into" each other. Researchers discovered that using the word "smashed" instead of "hit" could change how the participants remembered the accident.

A week later, the participants were once again asked a series of questions, including "Did you see broken glass?" Most of the participants correctly answered no. But those who had been asked the "smashed" version of the question in the initial interview were more likely to incorrectly believe that they had indeed seen broken glass.

Misinformation Effect Theories

Why does the misinformation effect happen, potentially leading to the formation of false memories? There are a few different theories.

• Blending of memories: One explanation is that the original information and the misleading information presented after the fact get blended together in the person's memory.
• Replacement of memories: Another possibility is that the misleading information actually overwrites the original memory of the event.
• Retrieval of memories: Researchers have also suggested that since the misleading information is more recent in memory, it tends to be easier to retrieve.
• Filling of memory gaps: In some cases, the pertinent data from the original event may never have been encoded into memory in the first place. So, when misleading information is presented, it is incorporated into the mental narrative to fill in these gaps in memory.

Factors Influencing the Misinformation Effect

Research has shown that there are several factors that can contribute to the misinformation effect, making it more likely that event happenings will be distorted and lead to false memories.

Discussing the Event With Other Witnesses

Talking to other witnesses following an event can distort a person's original memory. Their reports might conflict with the original memory of an event, and the new information might reshape or distort a witness's original memory of the events as they occurred.

Reading or Watching News Reports

Reading news stories and watching television reports of an accident or event can also contribute to misinformation. People often forget the source of information, which means they might mistakenly believe that a piece of information was something they observed personally when, in reality, it was something they heard in a post-event news report.

Repeated Exposure to Misinformation

The more often people are exposed to misleading information, the more likely they are to incorrectly believe that the misinformation was part of the original event.

The Passage of Time

If the misleading information is presented some time after the original memory, it is likely to be much more accessible in memory. In these cases, the misleading information is much easier to retrieve, effectively blocking the retrieval of the original, correct information.

How to Reduce the Misinformation Effect

What can prevent intervening information and events from altering memories or even creating false memories? Writing down your memory of an important event immediately after it happens is one strategy that might help minimize the effects.

Being aware that your memory can be influenced is another helpful and important strategy. While you might have a good memory, understand that everyone is susceptible to the misinformation effect.

That said, susceptibility may be even greater for people with a low need for cognition. People who have a high need for cognition tend to seek out lots of information to help make sense of events. People who have a low need for cognition, on the other hand, are more likely to use heuristics (mental shortcuts) to make sense of the world.

Research exploring the misinformation effect paradigm found that individuals with a high cognitive need were better at detecting differences between the original event memory and the misinformation. People with high cognitive need tend to think about ideas and pursue mentally challenging tasks, like puzzles.

How to Distinguish False Memories

Some argue that there is no way to distinguish a false memory from a real one. This creates a challenge not just when trying to remember a particular event, but also in memory research.

If there is video footage of the event, reviewing it can help you decide if your memories are real or if they could be false. It may also be beneficial to consider other people's recollections of the event. If they are all saying the same thing, and it is different than what you remember, the misinformation effect may be at play.