The Deese-Roediger-McDermott Paradigm and the Misinformation Effect.

 

What is the Deese-Roediger-McDermott (DRM) paradigm?

   To understand the Deese-Roediger-McDermott paradigm you must first understand what a paradigm is. A paradigm is a typical model or pattern of something. This paradigm is seen even at the encoding of memories in this task.

   The task consists of subjects being presented a list of words that are semantically related (such as all having connotations of sweetness  like cake and chocolate) which they have to remember. After being shown the words and a delay between the encoding of that memory and the retrieval, subjects are asked to recall or recognise the words they remember from the list. 

   

• In the 'recognition memory' version of the task, subjects are asked if they remember seeing words given to them. Some of the words asked about are words actually presented and some are relating words that the subjects haven't been presented called critical lure words. In the majority of cases, the critical lure word is recognised with a lot of confidence.
• In the 'recall memory' version of the task, subjects are asked to remember as many things from the list as possible without prompt. Typically, in a similar manner, the results show that subjects make up seeing a complete new word.

   The paradigm is largely considered a 'false-memory' paradigm yet DRM tasks also encapsulate the workings of semantic memory networks in the brain and show that it likely isn't an accidental process, nor is creating these benign false memories a disadvantage to humans. Remembering the gist of an experience with the brain filling in related ideas is an adaptive process that helps humans to relate things to use memories to their full advantage. This paradigm is the most common way to evoke 'spontaneous' false memories which arise due to internal cognitive processes.

What is the 'Misinformation effect'?

   The misinformation effect is the explanation behind the tendency for post-event information to interfere with the memory of an event. It is shown in a multitude of studies, originally and most famously conducted by Elizabeth Loftus and her colleagues, that even subtle introductions of information about a previous event can lead to an inaccurate recollection of that event.

   A prime example of evidence for this psychological effect is Loftus' study in which a film clip of a car crash was shown to participants and then after questions were asked which introduced post-event information to them which skewed their answers and memory of the clip. I went into more detail on the results of this study in my previous blog post (Notable psychologist's theories and studies). These tasks of seeing an event and then gaining post-event information are the most common teasts to evoke 'suggestion-based' false memories that are stimulated by external suggestion.