Memory gaps and errors refer to the incorrect recall, or complete loss, of information in the memory system for a certain detail and/or event. Memory errors may include remembering events that never occurred, or remembering them differently from the way they actually happened.Roediger, H. L., III, & McDermott, K. B. (1995). Creating false memories: Remembering words not presented in lists. Journal of Experimental Psychology: Learning, Memory, and Cognition, 21, 803–814 These errors or gaps can occur due to a number of different reasons, including the emotional involvement in the situation, expectations and environmental changes. As the retention interval between encoding and retrieval of the memory lengthens, there is an increase in both the amount that is forgotten, and the likelihood of a memory error occurring.
Overview There are several different types of memory errors, in which people may inaccurately recall details of events that did not occur, or they may simply misattribute the source of a memory. In other instances, imagination of a certain event can create confidence that such an event actually occurred. Causes of such memory errors may be due to certain cognitive factors, such as spreading activation, or to physiological factors, including brain damage, age or emotional factors. Furthermore, memory errors have been reported in individuals with schizophrenia and depression. The consequences of memory errors can have significant implications. Two main areas of concern regarding memory errors are in eyewitness testimony and cases of child abuse.
Types of memory errors
Blocking The feeling that a person gets when they know the information, but can not remember a specific detail, like an individual's name or the name of a place is described as the "tip-of-the-tongue" experience. The tip-of-the-tongue experience is a classic example of blocking, which is a failure to retrieve information that is available in memory even though you are trying to produce it. The information you are trying to remember has been encoded and stored, and a cue is available that would usually trigger its recollection. The information has not faded from memory and a person is not forgetting to retrieve the information. What a person is experiencing is a complete retrieval failure, which makes blocking especially frustrating. Blocking occurs especially often for the names of people and places, because their links to related concepts and knowledge are weaker than for common names. The experience of blocking occurs more often as we get older; this "tip of the tongue" experience is a common complaint amongst 60- and 70-year-olds.
Transience Transience refers to forgetting what occurs with the passage of time. Transience occurs during the storage phase of memory, after an experience has been encoded and before it is retrieved. As time passes, the quality of our memory also changes, deteriorating from specific to more general. German philosopher named Hermann Ebbinghaus decided to measure his own memory for lists of nonsense syllables at various times after studying them. He decided to draw out a curve of his forgetting pattern over time. He realized that there is a rapid drop-off in retention during the first tests and there is a slower rate of forgetting later on. Therefore, transience denotes the gradual change of a specific knowledge or idea into more general memories.Schacter, Daniel L.,["Psychology 2nd Ed."],"Worth Publishers", 2009, 2011.
Absentmindedness Absentmindedness is a gap in attention which causes memory failure. In this situation the information does not disappear from memory, it can later be recalled. But the lack of attention at a specific moment prevents the information from being recalled at that specific moment. A common cause of absentmindedness is a lack of attention. Attention is vital to encoding information in long-term memory. Without proper attention, material is much less likely to be stored properly and recalled later.Schacter, Daniel L., Daniel T. Gilbert, and Daniel M. Wegner. "Chapter 6: Memory." Psychology; Second Edition. N.p.: Worth, Incorporated, 2011. 244-45. When attention is divided, less activity in the lower left frontal lobe diminishes the ability for elaborative memory encoding to take place, and results in absentminded forgetting. More recent research has shown that divided attention also leads to less hippocampal involvement in encoding. A common example of absentmindedness is not remembering to carry out actions that had been planned to be done in the future, for example, picking up grocery items, and remembering times of meetings.Schacter, Daniel L., Daniel T. Gilbert, and Daniel M. Wegner. "Chapter 6: Memory." Psychology; Second Edition. N.p.: Worth, Incorporated, 2011. 245.
False memories False memories, sometimes referred to as confabulation, refer to the recollection of inaccurate details of an event, or recollection of a whole event that never occurred. Studies investigating this memory error have been able to successfully implant memories among participants that never existed, such as being lost in a mall as a child (termed the lost in the mall technique) or spilling a bowl of punch at a wedding reception.Loftus, E. (1997). Creating false memories. Scientific American, 277, 70–75 In this case, false memories were implanted among participants by their family members who claimed that the event had happened. This evidence demonstrates the possibility of implanting false memories on individuals by leading them to remember such events that never occurred. This memory error can be particularly worrisome in judicial settings, in which witnesses may have false recollections of a crime after it has happened, especially when told by others that particular things may have happened which did not.Johnson, M. & Raye, C. (1998). False memories and confabulation. Trends in Cognitive Sciences, 2(4), 137–145 Another area of concern regarding false memories is in cases of child abuse.
Problem of bias The problem of bias, which is the distorting influences of present knowledge, beliefs, and feelings on recollection of previous experiences. Sometimes what people remember from their past says less about what actually happened than about what they personally believe, feel, and the knowledge they have acquired at the present time. An individual's current moods can bias their memory recall, researchers have found. There are three types of memory biases, consistency bias, change bias and egocentric bias. Consistency bias is the bias to reconstruct the past to fit the present. Change bias is the tendency to exaggerate differences between what we feel or believe in the present and what we previously felt or believed in the past. Egocentric bias is a form of change bias, the tendency to exaggerate the change between the past and the present in order to make ourselves look good in any given situation.
Misinformation effect The misinformation effect refers to the change in memory due to the presentation of information that is relevant to the target memory, such as leading questions or suggestions.Loftus, E. F. & Hoffman, H. G. (1989). Misinformation and memory, the creation of new memories. Journal of Experimental Psychology, 118(1), 100–104 Memories are likely to be altered when questions are worded differently or when inaccurate information is presented. For example, in one experiment participants watched a video of an automobile accident and were then asked questions regarding the accident. When asked how fast the automobiles were driving when they smashed into each other, the speed estimate was higher than when asked how fast the automobiles were driving when they hit, bumped or collided into each other. Similarly, participants were more likely to report there being shattered glass present when the word smashed was used instead of other verbs.Loftus, E. F. & Palmer, J. C. (1974). Reconstruction of automobile destruction. Journal of Verbal Learning and Verbal Behavior, 13, 585–589 Evidently, memory recollection can be altered with misleading information after the event.
Source confusion Source confusion or unconscious transference,Deffenbacher, K.A., Bornstein, B.H., & Penrod, S.D. (2006). Mugshot exposure effects: Retroactive interference, mugshot commitment, source confusion, and unconscious transference. Law and Human Behaviour, 30(3), 287–307 involves the misattribution of the source of a memory. For instance, an individual may recall seeing an event in person when in reality they only witnessed the event on television. Ultimately, the individual has an inability to remember the source of information in which the content and the source become dissociated. This may be more likely for more distant memories, such as childhood memories. In more severe cases of source confusion, you can take fictional stories you heard from when you were younger and assimilated these stories being your childhood. For example, say your father told you stories about his life when he was a child every night before you went to sleep when you were a child. When you grow up, you might mistakenly remember these stories your dad told you as your own and integrate them into your childhood memories.Daniel L. Schacter, "Searching for memory: the brain, the mind, and the past", (New York, 1996)
Imagination inflation Imagination inflation refers to when a person remembers details of a memory that are exaggerated versions of the actual event or remember an entire memory that never occurred due to the act of imagination.Mazzoni, G. & Memon, A. (2003). Imagination can create false autobiographical memories. Psychological Science, 14(2), 186–188 That is, when one imagines an event occurring, their confidence that this event actually did occur increases. One reason for this may be due to the act of imagination increasing the familiarity of the event. When the event seems more familiar, it may become more likely for people to report it actually occurring. For instance, in an experiment participants were asked to imagine playing inside and then running outside toward a window, falling and breaking it, while other participants did not imagine anything. Participants who had imagined this scenario reported an increased level of confidence that the event had actually happened in comparison to those who did not imagine the event. This error can be caused simply by imagining an event.
Deese–Roediger–McDermott (DRM) paradigm Deese-Roediger-McDermott paradigm refers to the incorrect recall of features of an event that were not actually present, due to the features being related to a common theme.Deese, J. (1959). On the prediction of occurrence of particular verbal intrusions in immediate recall. Journal of Experimental Psychology, 58, 17–22 This paradigm has been demonstrated with the use of word lists and subsequent recognition tests. For example, experiments have shown that if a research participant is presented with the words: bed rest awake tired dream wake snooze snore nap yawn drowsy, there is a high likelihood that the participant will falsely recall that the word sleep was in the list of words. These results show a significant illusion in memory, in which people remember items that were never presented simply due to their relation with other items in a common theme.
Schematic errors