[1] These errors or gaps can occur due to a number of different reasons, including the emotional involvement in the situation, expectations and environmental changes.
Two main areas of concern regarding memory errors are in eyewitness testimony and cases of child abuse.
[3] German philosopher named Hermann Ebbinghaus decided to measure his own memory for lists of nonsense syllables at various times after studying them.
[5] 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.
The problem of bias, which is the distorting influences of present knowledge, beliefs, and feelings on recollection of previous experiences.
[9] 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.
[16] Intrusion errors refer to when information that is related to the theme of a certain memory, but was not actually a part of the original episode, become associated with the event.
One idea regarding how intrusion errors work is due to a lack of recall inhibition, which allows irrelevant information to be brought to awareness while attempting to remember.
The first are known as extra-list errors, which occur when incorrect and non-related items are recalled, and were not part of the word study list.
[18] Although these two categories of intrusion errors are based on word list studies in laboratories, the concepts can be extrapolated to real-life situations.
[24] Personal life effects refer to the recall and belief in events as declared by family members or friends for having actually happened.
[25] Personal life effects are largely based on suggestive influences from external sources, such as family members or a therapist.
[7] Other influential sources may include media or literature stories which involve details that are believed to have been experienced or witnessed, such as a natural disaster close to where one resides, or a situation that is common and could have occurred, such as getting lost as a child.
This is likely to occur with high connection densities, in which the incorrect (but associated) node was activated and thus recalled, instead of the target memory.
Memory errors can also depend on the method of encoding used when initially experiencing or learning information, known as transfer-appropriate processing.
First, proactive interference has to do with difficulty in learning new material based on the inability to override information from older memories.
Possible reasons for this are increased source confusion for the event and findings that older persons have decreased levels of processing when first presented with new information.
[44] The visual form of processing relies on the ability to see information and break it down into its components (e.g. see the word "dog", composed D, O, and G).
Phonology relies on creating links to information through sound such as cues and tricks for memory (e.g. Dog rhymes with Fog).
Memory errors can commonly be found in types of abnormal psychology such as Alzheimer's disease, depression, and schizophrenia.
However, studies have shown that the opposite may be true for patients with Alzheimer's, such that cues may actually decrease perform on priming tasks.
Relative to the findings that retrieval cues may actually hurt recall performance, one study by Kramer et al. showed that intrusions are most commonly associated with cue-recall tasks.
Since verbal intrusions are a common aspect of Alzheimer's,[54] some researchers believe that this characteristic may be helpful in the diagnosis of the disease.
[56] Long-term memory, large capacity able to retain information over long periods of time, does however show impairment in the case of depressed individuals.
They tend to have difficulties in recall and recognition for both verbal and visuo-spatial material with intervals of a few minutes or even hours creating complex memory errors in relation to speech and surrounding details.
[56] Individuals suffering with depression also showed a specific deficit in retrieving information meaningfully organized in their semantic memory, conceptual knowledge about the real world.
In the case of implicit memory, when previous information influences ongoing responses, there has been little to no proof of a deficit in relations to depressed individuals.
Intrusion errors can commonly be found in the recall portion of a memory test when a participant includes items that were not on the original list that was presented.
[57] These types of errors are linked to problems with self-monitoring, increased positive and disorganized symptoms (confusion within the brain), and poor executive functioning.
Such features include: Memory errors regarding the recovery of repressed childhood abuse can occur due to post-event suggestions from a trusted source, such as a family member, or more commonly, a mental health professional.