Flashback (psychological phenomenon)

A flashback, or involuntary recurrent memory, is a psychological phenomenon in which an individual has a sudden, usually powerful, re-experiencing of a past experience or elements of a past experience. These experiences can be happy, sad, exciting, or any other emotion one can consider. The term is used particularly when the memory is recalled involuntarily, and/or when it is so intense that the person "relives" the experience, unable to fully recognize it as memory and not something that is happening in "real time".

Flashbacks are the "personal experiences that pop into your awareness, without any conscious, premeditated attempt to search and retrieve this memory". These experiences occasionally have little to no relation to the situation at hand. Flashbacks to those suffering posttraumatic stress disorder can be so disruptive as to seriously affect day-to-day living.

Memory is divided into voluntary (conscious) and involuntary (unconscious) processes that function independently of each other. Theories and research on memory dates back to Hermann Ebbinghaus, who began studying nonsense syllables. Ebbinghaus classified three distinct classes of memory: sensory, short term, and long-term memory.Sensory memory is made up of a brief storage of information within a specific medium (the line you see after waving a sparkler in your field of vision is created by sensory memory).Short term memory is made up of the information currently in use to complete the task at hand.Long term memory is composed of the systems used to store memory over long periods. It enables one to remember what happened two days ago at noon, or who called last night.

Miller (1962–1974) declared that studying such fragile things as involuntary memories should not be done. This appears to have been followed since very little research has been done on flashbacks in the cognitive psychology discipline. Flashbacks have been studied within a clinical discipline however, and they have been identified as symptoms for many disorders, including post traumatic stress disorder.

Due to the elusive nature of involuntary recurrent memories, very little is known about the subjective experience of flashbacks. However, theorists agree that this phenomenon is in part due to the manner in which memories of specific events are initially encoded (or entered) into memory, the way in which the memory is organized, and also the way in which the individual later recalls the event. Overall, theories that attempt to explain the flashback phenomenon can be categorized into one of two viewpoints. The special mechanism view is clinically oriented in that it holds that involuntary memories are due to traumatic events, and the memories for these events can be attributed to a special memory mechanism. On the other hand, the basic mechanism view is more experimentally oriented in that it is based on memory research. This view holds that traumatic memories are bound by the same parameters as all other every-day memories. Both viewpoints agree that involuntary recurrent memories result from rare events that would not normally occur.

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