Memory repression

In psychology, memory inhibition is the ability not to remember irrelevant information. The scientific concept of memory inhibition should not be confused with everyday uses of the word "inhibition". Scientifically speaking, memory inhibition is a type of cognitive inhibition, which is the stopping or overriding of a mental process, in whole or in part, with or without intention.

Memory inhibition is a critical component of an effective memory system. While some memories are retained for a lifetime, most memories are forgotten. According to evolutionary psychologists, forgetting is adaptive because it facilitates selectivity of rapid, efficient recollection. For example, a person trying to remember where he parked his car would not want to remember every place he has ever parked. In order to remember something, therefore, it is essential not only to activate the relevant information, but also to inhibit irrelevant information.

There are many memory phenomena that seem to involve inhibition, although there is often debate about the distinction between interference and inhibition.

In the early days of psychology, the concept of inhibition was prevalent and influential (e.g., Breese, 1899; Pillsbury, 1908; Wundt, 1902). These psychologists applied the concept of inhibition (and interference) to early theories of learning and forgetting. Starting in 1894, German scientists Muller and Shumann conducted empirical studies that demonstrated how learning a second list of items interfered with memory of the first list. Based on these experiments, Muller argued that the process of attention was based on facilitation. Arguing for a different explanation, Wundt (1902) claimed that selective attention was accomplished by the active inhibition of unattended information, and that to attend to one of several simultaneous stimuli, the others had to be inhibited. American Psychologist Walter Pillsbury combined Muller and Wundt's arguments, claiming that attention both facilitates information that is wanted and inhibits information that is unwanted.

In the face of behaviorism during the late 1920s through the 1950s, and through the early growth of cognitive psychology in the late 1950s and early 1960s, inhibition largely disappeared as a theory. Instead, classical interference theory dominated memory research until as late as 1960. By the early 1970s, however, classical interference theory began to decline due to its reliance on associationism, to its inability to explain the facts of interference or how interference applies to everyday life, and to newly published reports on proactive and retroactive inhibition.

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