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.[\[1\]](https://en.wikipedia.org/wiki/Memory_inhibition?utm_source=chatgpt.com#cite_note-MacLeod2007Concept-1) Memory inhibition is a critical component of an effective memory system.[\[2\]](https://en.wikipedia.org/wiki/Memory_inhibition?utm_source=chatgpt.com#cite_note-2) While some memories are retained for a lifetime, most memories are forgotten.[\[3\]](https://en.wikipedia.org/wiki/Memory_inhibition?utm_source=chatgpt.com#cite_note-WadeTavris2010-3) According to evolutionary psychologists, forgetting is adaptive because it facilitates selectivity of rapid, efficient recollection.[\[4\]](https://en.wikipedia.org/wiki/Memory_inhibition?utm_source=chatgpt.com#cite_note-Mathews2011Mnemonic-4) For example, a person trying to remember where they parked their car would not want to remember every place they have 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. ## History \ [edit\] In the early days of psychology, the concept of inhibition was prevalent and influential (e.g., Breese, 1899; Pillsbury, 1908; Wundt, 1902).[\[1\]](https://en.wikipedia.org/wiki/Memory_inhibition?utm_source=chatgpt.com#cite_note-MacLeod2007Concept-1) These psychologists applied the concept of inhibition (and interference) to early theories of learning and forgetting.[\[5\]](https://en.wikipedia.org/wiki/Memory_inhibition?utm_source=chatgpt.com#cite_note-Dempster1995Historical-5) 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.[\[5\]](https://en.wikipedia.org/wiki/Memory_inhibition?utm_source=chatgpt.com#cite_note-Dempster1995Historical-5) Based on these experiments, Muller argued that the process of attention was based on facilitation.[\[6\]](https://en.wikipedia.org/wiki/Memory_inhibition?utm_source=chatgpt.com#cite_note-Dagenbach1994-6) Arguing for a different explanation, Wundt (1902) claimed that selective attention was accomplished by the active inhibition of unattended information,[\[6\]](https://en.wikipedia.org/wiki/Memory_inhibition?utm_source=chatgpt.com#cite_note-Dagenbach1994-6) and that to attend to one of several simultaneous stimuli, the others had to be inhibited.[\[1\]](https://en.wikipedia.org/wiki/Memory_inhibition?utm_source=chatgpt.com#cite_note-MacLeod2007Concept-1) 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.[\[6\]](https://en.wikipedia.org/wiki/Memory_inhibition?utm_source=chatgpt.com#cite_note-Dagenbach1994-6)[\[7\]](https://en.wikipedia.org/wiki/Memory_inhibition?utm_source=chatgpt.com#cite_note-Carr2007Inhibit-7) 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,[\[8\]](https://en.wikipedia.org/wiki/Memory_inhibition?utm_source=chatgpt.com#cite_note-Bower2000-8) inhibition largely disappeared as a theory.[\[1\]](https://en.wikipedia.org/wiki/Memory_inhibition?utm_source=chatgpt.com#cite_note-MacLeod2007Concept-1) Instead, classical interference theory dominated memory research until as late as 1960.[\[5\]](https://en.wikipedia.org/wiki/Memory_inhibition?utm_source=chatgpt.com#cite_note-Dempster1995Historical-5) By the early 1970s, however, classical interference theory began to decline due to its reliance on associationism,[\[8\]](https://en.wikipedia.org/wiki/Memory_inhibition?utm_source=chatgpt.com#cite_note-Bower2000-8) 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.[\[5\]](https://en.wikipedia.org/wiki/Memory_inhibition?utm_source=chatgpt.com#cite_note-Dempster1995Historical-5) Since the mid-1980s, there has been a renewed interest in understanding the role of inhibition in cognition.[\[6\]](https://en.wikipedia.org/wiki/Memory_inhibition?utm_source=chatgpt.com#cite_note-Dagenbach1994-6) Research on a wide variety of psychological processes, including attention, perception, learning and memory, psycholinguistics, cognitive development, aging, learning disabilities, and neuropsychology, suggests that resistance to interference (which implies capacity for inhibition) is an important part of cognition.[\[5\]](https://en.wikipedia.org/wiki/Memory_inhibition?utm_source=chatgpt.com#cite_note-Dempster1995Historical-5) More recently, researchers suggest that the hippocampus plays a role in the regulation of disliked and competing memories, and fMRI studies have shown hippocampus activity during inhibition processes.[\[9\]](https://en.wikipedia.org/wiki/Memory_inhibition?utm_source=chatgpt.com#cite_note-9) ## Empirical research \ [edit\] ### Part-set cuing effect \ [edit\] The "part-set cuing effect" was initially discovered by Slamecka (1968), who found that providing a portion of to-be-remembered items as test cues often impairs retrieval of the remaining un-cued items compared with performance in a no-cue (free-recall) control condition.[\[10\]](https://en.wikipedia.org/wiki/Memory_inhibition?utm_source=chatgpt.com#cite_note-10) Such an effect is intriguing because normally cues are expected to aid recall (e.g., Tulving & Pearlstone, 1966).[\[11\]](https://en.wikipedia.org/wiki/Memory_inhibition?utm_source=chatgpt.com#cite_note-11) A prominent figure in retrieval-based inhibition research, Henry L. Roediger III was another one of the first psychologists to propose the idea that retrieving an item reduces the subsequent accessibility of other stored items.[\[12\]](https://en.wikipedia.org/wiki/Memory_inhibition?utm_source=chatgpt.com#cite_note-Nairne-12) Becoming aware of the part-set cueing effect reduces the effect, such that relearning part of a set of previously learned associations can improve recall of the non-relearned associations.[\[13\]](https://en.wikipedia.org/wiki/Memory_inhibition?utm_source=chatgpt.com#cite_note-13) ### Retrieval-induced forgetting \ [edit\] Main article: Retrieval-induced forgetting Anderson and Spellman's model of retrieval-induced forgetting suggests that when items compete during retrieval, an inhibitory process will serve to suppress those competitors. For instance, retrieval of one meaning for a word (e.g. the verb meaning of the word _sock_) will tend to inhibit the dominant meaning of that word (e.g. the noun meaning of _sock_).[\[15\]](https://en.wikipedia.org/wiki/Memory_inhibition?utm_source=chatgpt.com#cite_note-GorfeinBrown2007SayingNo-15) In 1995, Anderson and Spellman conducted a three-phase study using their retrieval-induced forgetting model to demonstrate unlearning as inhibition.[\[16\]](https://en.wikipedia.org/wiki/Memory_inhibition?utm_source=chatgpt.com#cite_note-16) - Study phase: Participants study a list of category-exemplar pairings where some exemplars are semantically similar in that they belong to another category besides the one they are explicitly paired with (e.g. Food-Cracker, Food-Strawberry, Red-Tomato, Red-Blood). - Retrieval-practice phase: Participants are cued to practice remembering some of the exemplars given the category cue (e.g. Red-Bl\_\_). - Test phase: Given each category as a cue, the participant tries to recall the exemplar (e.g. Food-C\_\_, Food-S\_\_, Red-T\_\_, Red-Bl\_\_). Anderson and Spellman observed that items that shared a semantic relationship with practiced information was less recallable. Using the example from above, recall of items related to practiced information, including _tomato_ and _strawberry_ was lower than recall for _cracker_, even though strawberry is part of a different pair. This finding suggests that associative competition by explicit category cue is not the only factor in retrieval difficulty. They theorized that the brain suppresses, or inhibits, non-practiced attributes.[\[1\]](https://en.wikipedia.org/wiki/Memory_inhibition?utm_source=chatgpt.com#cite_note-MacLeod2007Concept-1) This explains why an item that is very similar to tomato, but not from the same pair, also exhibits decreased recall rate.