Autobiographical Memory - Emotion - Negative

Negative

Negative memories generally fade faster than positive memories of similar emotional importance and encoding period. This difference in retention period and vividness for positive memories is known as the fading affect bias. In addition, coping mechanisms in the mind are activated in response to a negative event, which minimizes the stress and negative events experienced.

While it seems adaptive to have negative memories fade faster, sometimes it may not be the case. Remembering negative events can prevent us from acting overconfident or repeating the same mistake, and we can learn from them in order to make better decisions in the future.

However, increased remembering of negative memories can lead to the development of maladaptive conditions. The effect of mood-congruent memory, wherein the mood of an individual can influence the mood of the memories they recall, is a key factor in the development of depressive symptoms for conditions such as dysphoria or major depressive disorder.

Dysphoria// Individuals with mild to moderate Dysphoria show an abnormal trend of the fading affect bias. The negative memories of dysphoric individuals did not fade as quickly relative to control groups, and positive memories faded slightly faster. In severely dysphoric individuals the fading affect bias was exacerbated; negative memories faded more slowly and positive memories faded more quickly than non-dysphoria individuals.

Unfortunately, this effect is not well understood. One possible explanation suggests that, in relation to mood-congruent memory theory, the mood of the individual at the time of recall rather than the time of encoding has a stronger effect on the longevity of negative memories. If this is the case, further studies should hopefully show that changes in mood state will produce changes in the strength of the fading affect bias.

Depression// Depression impacts the retrieval of autobiographical memories. Adolescents with depression tend to rate their memories as more accurate and vivid than never-depressed adolescents, and the content of recollection is different.

Individuals with depression encounter trouble remembering specific personal past events, and instead recall more general events (repeated or recurring events). Specific memory recall can further be inhibited by significant psychological trauma occurring in comorbidity. When a specific episodic memory is recalled by an individual with depression, details for the event are almost non-existent and instead purely semantic knowledge is reported.

The lack of remembered detail especially affects positive memories; generally people remember positive events with more detail than negative events, but the reverse is seen in those with depression. Negative memories will seem more complex and the time of occurrence will be more easily remembered than positive and neutral events. This may be explained by mood congruence theory, as depressed individuals remember negatively charged memories during frequent negative moods. Depressed adults also tend to actively rehearse negative memories, which increases their retention period and vividness.

Another explanation may be the tendency for individuals suffering from depression to separate themselves from their positive memories, and focus more on evidence that supports their current negative self-image in order to keep it intact. Depressed adults also recall positive memories from an observer perspective rather than a field perspective, where they appear as a spectator rather than a participant in their own memory.

Finally., the autobiographical memory differences may be attributed to a smaller posterior hippocampal volume in any individuals going through cumulative stress.