Proactive vs. Retroactive Interference: How Memories Compete

4 days ago

21 min read

Author: Angela Bogdanova · Published: October 12, 2026 · Editorial Policy

Research cluster: Memory & Forgetting · Written by Artificial Sapiens

Proactive and retroactive interference describe two directions in which learning can make another memory harder to access. Proactive interference occurs when earlier learning impairs learning or remembering newer information. Retroactive interference occurs when later learning impairs memory for earlier information. Both are experimentally documented effects, especially when different experiences share cues, meanings, or responses. They are central to the psychology of forgetting because a failed recall attempt can reflect competition among memories rather than the disappearance of a stored experience. A critical contemporary overview is Kliegl and Bäuml's review of interference and inhibition.

The simplest example is a changed password. If the old password keeps coming to mind when you try to use the replacement, the earlier response is interfering with the newer one: proactive interference. If repeated use of the new password makes it harder to produce the old password when you legitimately need it, the newer response is interfering with the earlier one: retroactive interference. The same two associations may therefore produce both effects, depending on which answer is required at the test.

Proactive vs. retroactive interference: the essential difference

Proactive interference means that an earlier memory makes a later target memory harder to learn or retrieve. Its direction is from the past toward the new. The target is the more recent information; the competitor is older information. Retroactive interference means that subsequent learning makes an earlier target harder to retrieve. Its direction is from the new toward the past. The target is the earlier information; the competitor is what came afterward.

Consider two lessons. On Monday, a student learns that the Spanish word for a particular concept is one term. On Wednesday, the student learns a related word in Italian. During the Italian test, the Spanish response may intrude: that is proactive interference. During a later Spanish test, the Italian response may intrude: that is retroactive interference. Merely studying two languages, however, does not establish interference. A researcher must show that the competing learning actually impairs a relevant measure relative to an appropriate comparison condition.

A reliable way to identify the direction is to ask three questions: What is the target memory? Was the interfering information learned before or after that target? Does the test show impairment compared with a condition with less competition? The target, rather than the most recently used word or the time of the final mistake, determines the classification.

A compact comparison

For proactive interference, the sequence is old learning → new learning → test of new learning, and the old association competes with the new answer. For retroactive interference, the sequence is old learning → new learning → test of old learning, and the new association competes with the old answer. Both involve overlapping information; both can produce intrusions, slower retrieval, or reduced accuracy; both can also be moderated by remembering when a change occurred. Neither effect alone demonstrates that a memory has been erased.

What does memory interference mean in psychology?

Memory interference is a reduction in learning or later memory performance associated with other information or activity. In an interference experiment, the central question is whether other learned material makes a target harder to remember. Researchers distinguish this behavioral result from a proposed mechanism. Competing retrieval responses, weaker encoding, altered associations, contextual confusion, and changes during consolidation can yield superficially similar errors.

The distinction matters because human remembering is cue-dependent. A person usually retrieves information using a word, location, question, emotional context, or internal goal. If several experiences share that cue, the cue can activate multiple candidate memories. Producing the intended response then requires selecting the appropriate episode or association, including its temporal context. Kliegl and Bäuml (2021) review both behavioral and neuroimaging evidence for competing responses, and describe unresolved questions about encoding and retrieval mechanisms.

An interference effect is defined by a comparison, not by how frustrated someone feels. One occasion of confusion is compatible with interference, a source error, limited attention, incomplete original learning, fatigue, or ordinary uncertainty. Experiments use comparison lists, balanced materials, controlled delays, and tests of both target memories to isolate the contribution of competing material.

How researchers demonstrate interference: the A–B, A–C experiment

The standard paired-associate paradigm helps isolate why similar memories compete. First, a participant studies cue A paired with response B; for example, TREE–GLASS. Next, the same cue appears with a changed response C; for example, TREE–RIVER. On the final test, the researcher presents TREE and asks for either the first response or the second response. A control condition uses unrelated pairs so that learning one association does not introduce a competitor to the other.

If the participant is asked for the second response, RIVER, but earlier learning of TREE–GLASS reduces accuracy or produces GLASS intrusions, the observed cost is proactive interference. If asked for the original response, GLASS, but learning TREE–RIVER has reduced its accessibility, the cost is retroactive interference. Both effects require a suitable baseline comparison; merely guessing the wrong word is not sufficient evidence.

The design is sometimes called A–B, A–D, with a different letter for the changed response. These labels do not designate separate theories. They express the same experimental structure: a cue is reused, and the associated response changes. Researchers can also study separate word lists, stories, spatial locations, visual objects, or repeated events. Their measurement choices matter: free recall, cued recall, recognition accuracy, reaction time, and source identification need not reveal the same interference pattern.

Why overlapping cues are so important

Interference often grows when two memories compete for the same retrieval cue. A new office address is especially vulnerable to confusion with the previous address because the question “What is our office address?” activates both. A different cue, such as “Where was the office before the move?”, can help identify the older episode if its temporal source was encoded and remains accessible.

Similarity is multidimensional. Two words can share meaning, spelling, sound, category, or an associated response; two autobiographical events can share a person, setting, or routine. Which dimension matters depends on the test. It is more precise to ask whether memories overlap in the information needed to answer a particular question than to treat all similar experiences as equally interfering. The 2020 review of proactive interference buildup and release examines the different experimental paradigms and their proposed mechanisms.

Classic interference theory: what the historical studies established

Early twentieth-century researchers used interference experiments to challenge explanations of forgetting based entirely on elapsed time. Their results remain historically important, although contemporary cognitive science studies multiple mechanisms, including encoding, contextual retrieval, neural competition, and consolidation. A behavioral pattern from a word-list experiment is not a complete biological theory.

Retroactive interference and related material

In a classic study, McGeoch and McDonald investigated how the relationship between original and intervening material influenced later recall. Their 1931 paper, Meaningful Relation and Retroactive Inhibition, helped show that what people do during a retention interval matters and that associations between study materials can change the degree of interference. Historical terminology commonly used inhibition where contemporary researchers often say interference; the labels should not be treated as proof of a specific neural suppression mechanism.

The key experimental lesson is that equal time intervals do not necessarily produce equal forgetting. Learning additional, overlapping material can change subsequent recall relative to spending that interval on other activities. But studies must also control for rehearsal opportunities, fatigue, initial learning strength, and testing procedures. Consequently, the evidence supports interference as an important cause of forgetting, not the assertion that time-related change is impossible.

Underwood and proactive interference

In Interference and Forgetting (1957), Benton J. Underwood argued that previously learned experimental lists contributed substantially to later list forgetting. The important insight was that the learning history of a participant can influence recall even when a study appears to be measuring retention of one newly learned list. Earlier trials are an experimental variable, not neutral background.

Underwood's influential analysis relied heavily on the verbal-learning procedures of its era. It should not be generalized into a universal percentage of everyday forgetting, or an assertion that every memory weakens only because of other memories. Modern reviews investigate how much impairment originates during encoding, how much appears at retrieval, and how performance changes when conditions encourage people to recollect change.

Keppel and Underwood: proactive buildup across short-term trials

In their 1962 experiments, Keppel and Underwood observed how previously tested verbal items contributed to losses in short-term retention tasks. Their paper, Proactive Inhibition in Short-Term Retention of Single Items80023-1), is a landmark demonstration that repeated trials can introduce competition. It complicates simple interpretations in which declining performance after a short distraction interval is attributed solely to rapid passive decay.

The finding does not prove that short-term representations never change with time. The broader lesson is methodological: to interpret a forgetting curve, researchers must examine both time elapsed and the material participants encoded on previous trials. Treating all trials as interchangeable can conceal proactive interference.

Proactive interference buildup and release

A sequence of similar lists or short-term trials can lead to progressive difficulty recalling the newest items. Earlier items accumulate as possible answers and may make the current set harder to encode distinctly or retrieve selectively. This is called the buildup of proactive interference. It is a repeatable laboratory phenomenon, but the magnitude depends on task structure and population.

Researchers have also observed release from proactive interference. When the next list differs meaningfully from prior lists—for example, when words change from one semantic category to another—recall of the newest list may improve. This improvement indicates that the dimension along which items are encoded or selected matters for interference. It does not show that all older memories suddenly become inaccessible. The review by Kliegl and Bäuml (2020) surveys buildup and release across paired-associate learning, Brown–Peterson tasks, and multiple-list learning, including neural evidence.

Category switching is therefore a useful experimental probe of encoding and retrieval processes. Its practical meaning is narrower than the popular advice to “switch subjects constantly.” Whether alternating tasks helps a particular student depends on the tasks, time scale, practice goals, and long-term test. Evidence for spaced learning comes from a related but distinct research literature.

Retroactive interference: what happens after the first memory is learned?

Retroactive interference is often demonstrated when a person learns material, then learns something related before being tested on the original. If memory for the first set suffers relative to an appropriate control group, the new learning has produced a retroactive cost.

The size and explanation of that cost can vary. A newer response may be more available and intrude when the old cue is presented. Alternatively, learning the second association can alter how the first episode is represented or how readily it is reinstated. Work on memory consolidation also raises questions about whether some intervening activities affect stabilization before the final retrieval attempt. The appropriate conclusion is that multiple processes can contribute to a measured retroactive effect; the test alone cannot decide among them.

The popular slogan “new memories overwrite old ones” expresses one possible intuition, not a universal empirical mechanism. A person can sometimes retrieve both old and new responses, especially after a contextual reminder or an explicit question about the order of events. Under other conditions, strong new learning may make an old response persistently difficult to produce. Experiments are needed to determine what changed in each case.

Competition, inhibition, integration, and memory for change

Contemporary accounts examine how the brain handles several memories associated with overlapping information. Some models emphasize competition: when a cue activates multiple candidates, selection is harder. Other accounts investigate inhibitory control during selective retrieval, changes during encoding, and the integration of old and new episodes into a structured representation. These proposed processes are related, but their presence in a particular experiment cannot be inferred from the label proactive or retroactive interference alone.

Retrieval competition and source selection

One possibility is that multiple responses remain accessible, but the wrong one is activated first or receives too much weight. A person asked for a current address may automatically produce the old address because it has been rehearsed for years. Access to a cue specifying “after the move” can support the correct choice. This account predicts that cue quality, the relative strength of alternatives, and knowledge of the temporal context will influence performance.

Neuroimaging studies associate demanding selection among competing memories with prefrontal and medial temporal systems, but an activated region is not a unique signature of one psychological mechanism. The 2021 interference-and-inhibition review discusses evidence implicating lateral prefrontal cortex during proactive interference and hippocampal–medial prefrontal contributions to reminding and integration.

Inhibition and retrieval-induced forgetting are related, but distinct

When people deliberately retrieve a target, the retrieval process can sometimes make related competitors less accessible later. In a 2015 Nature Neuroscience study, Wimber and colleagues reported suppression of neural patterns associated with competing memories during repeated retrieval, and this pattern predicted later forgetting. That work is important for understanding memory competition and inhibitory accounts.

Retrieval-induced forgetting, however, is a separate experimental phenomenon. It is defined by reduced later recall of related items following selective retrieval practice. Proactive and retroactive interference are defined by the temporal relationship between target information and competing learning. The phenomena can interact, but neither term should be used as a synonym for the other. The planned EN-24 retrieval-induced forgetting article owns that independent search intent.

Detecting a change can reverse interference

Memory research has uncovered a striking complication: encountering a changed fact can sometimes make memory better rather than worse. In Wahlheim and Jacoby (2013), participants benefited when they detected a changed cue–response relationship and later recollected that change. Remembering that a cue once led to B and later led to C can preserve both responses along with their order. When change was not detected or not recollected, proactive interference was more likely.

This memory-for-change approach is also relevant to retroactive effects. Jacoby, Wahlheim, and Kelley (2015) compared processes that help people distinguish and connect changed associations. Later studies of reminding and retroactive effects found that noticing the changed response could yield facilitation under some conditions. The scientific lesson is that additional learning can create a competitor, provide a useful reminder, or both.

What 2026 experiments add

A 2026 four-experiment study by Cox and colleagues tested how retention delay and awareness of changes affected interference. Retroactive interference appeared on immediate but not delayed tests in key conditions; proactive intrusions could be greater after delay. When participants recognized and remembered that a response had changed, later retrieval could improve. These findings show why target, test delay, study-phase retrieval, and temporal-source memory must be examined together.

One recent study does not establish a universal timetable for interference. Its value is theoretical precision: learning a competing association changes more than the number of possible answers. It can also prompt retrieval of the first association and integrate the two learning episodes, with consequences depending on what the final test requests.

The brain and memory interference

Interference involves distributed memory systems rather than a single “interference center.” The hippocampus helps bind elements of episodes and support retrieval of contextually specific information. Prefrontal networks are implicated in selecting goal-relevant responses and managing competition. Neural representations of overlapping experiences can be differentiated or reactivated together depending on learning and testing conditions.

For example, an EEG study of competitive retrieval found that episodic contexts were incidentally reinstated while participants attempted to remember overlapping word pairs. The study observed proactive interference in its behavioral data but not a corresponding retroactive effect. This asymmetry is informative: the two kinds of interference are conceptually paired, but a particular task does not have to produce both.

Neuroimaging and electrophysiology offer converging evidence about retrieval dynamics, yet they also involve interpretation. Correlations between brain activity and recall cannot alone distinguish whether a trace was weakened, a competing trace became dominant, or contextual selection failed. Experimental manipulation and complementary behavioral controls remain necessary.

What makes interference stronger or weaker?

Interference often depends on overlap between the target and competing information, but the relationship is conditional rather than mechanical. Shared retrieval cues, semantic categories, familiar routines, and similar environments can increase competition. Distinctive temporal, spatial, or conceptual cues can help differentiate episodes.

Initial learning strength also matters. A highly familiar old response may intrude when a new response is being learned, while repeated exposure to a replacement can make that newer response more prominent on a later test. The exact outcome depends on whether the task tests initial acquisition, delayed recall, recognition, speed, or source accuracy.

The timing of tests changes results because accessibility and contextual recollection evolve over delays. The Cox et al. (2026) experiments specifically caution against assuming that proactive and retroactive costs have constant sizes over time. Detecting a change while learning, making the historical order explicit, and receiving accurate cues can alter which answer is retrieved.

Individual differences and age also matter, but the effects are not reducible to a diagnosis or a simple decline curve. In a 2022 study of value-directed remembering, Murphy and Castel examined how proactive and retroactive interference interacted with prioritized information in younger and older adults. Another study of reminding in younger and older adults found that remembering change could benefit both groups while the pattern of source intrusions differed. Neither finding supports treating a routine interference error as evidence of dementia.

Everyday examples: classify the target, not just the mistake

A new phone number or address

You move and continue saying the former street address when filling out a form requesting your current address. The old association is intruding on the new target, illustrating proactive interference. Months later, when a tax form asks for the address from an earlier year and the new address comes to mind instead, the direction is retroactive. The two errors depend on which address is being tested.

Changing a password or PIN

An old password competing with a newly assigned one illustrates proactive interference. Repeatedly using the replacement until the former password becomes difficult to retrieve illustrates a possible retroactive effect. Password managers and secure storage practices can reduce the need to remember multiple competing credentials; this is a practical observation, not evidence that all password slips have one cognitive cause.

Languages with overlapping vocabulary

A long-practiced word in one language may intrude when a learner is asked for a newer word in another language. A new language can also affect retrieval of an older one. Transfer may sometimes be beneficial if knowledge shares rules and meanings, so similarity does not imply inevitable interference. The direction should be determined by the tested target and the observed cost.

Revised procedures at work

An employee who learned a previous interface may use the old sequence after software changes: proactive interference. After months of practicing the new interface, the employee may struggle to demonstrate the previous procedure for an archived training exercise: retroactive interference. Distinct version labels and practice in the required context can clarify which procedure applies.

Similar facts in successive courses

If last semester's definitions compete with changed definitions in the current course, proactive interference is plausible. If the current formulation dominates during a test specifically about the historical theory, retroactive interference is plausible. Discriminating when and why a definition changed can sometimes support both memories, which is why explicit comparison can be more useful than treating one version as something to suppress.

Names and roles in familiar settings

Repeatedly calling a new coworker by the name of the person who previously held the job may reflect proactive interference if both names are sufficiently encoded and the old association intrudes. Later, when asked to identify the former coworker, the newer name may be more accessible. But a name not attended to at introduction may simply have been poorly encoded; it is premature to infer interference from every name lapse.

Evidence-based ways to manage competing information

Memory research suggests several reasonable approaches, but evidence from a laboratory interference task should not be marketed as a guarantee of improved real-world memory. Practical strategies can be chosen according to what must be remembered, how similar the materials are, and when correct recall will be required.

Make the change and its context explicit

When a fact or procedure changes, record both versions and label them by date, place, role, or applicability. For example: “Before June: Room 214. Starting June: Room 318.” Then test yourself by asking which version was true at each time. This approach follows research on detection and recollection of change, including Wahlheim and Jacoby's experiments. The intervention has a clear theoretical rationale, though no one should claim that a particular note format has been proven to eliminate all interference.

Retrieve the exact target under the right cue

When the goal is to remember current information, practice answering the question as it will appear in the real task and provide feedback. When the goal is to preserve historical information, rehearse questions that explicitly ask for the previous response. Retrieval practice has substantial evidence for improving later recall in many learning settings: Karpicke and Roediger (2008) found substantial benefits of repeated testing for delayed retention. A practice test can also reinforce competitors or create new retrieval dynamics, so the task should specify the intended answer.

Space study sessions and vary cues deliberately

Spreading successful retrieval across sessions can strengthen retention. A major meta-analysis by Cepeda and colleagues (2006) synthesized hundreds of comparisons and showed that spacing and target retention interval interact. More recent classroom meta-analytic research found benefits for distributed over massed practice in applied learning. These are findings about learning schedules, not direct proof that spacing always prevents proactive or retroactive interference. Distinguish similar items during review instead of repeatedly practicing one answer without a source cue.

Build distinctive examples and comparisons

When two definitions, formulas, or procedures overlap, organize a side-by-side comparison stating the shared cue, the distinguishing context, and the correct answer under each condition. Generating an explanation for why an answer applies may make the representation more distinctive. The precise incremental effect of a particular comparison exercise depends on the learning task; its main rationale here is improved discrimination between competing versions.

Consider brief quiet periods after concentrated learning

A quiet interval after learning can reduce immediate exposure to competing material and may support retention. A 2025 systematic review and meta-analysis of wakeful rest reported an overall benefit across its included comparisons, and a second meta-analysis examined heterogeneity and found stronger effects in some populations than others. Quiet rest is a plausible low-cost study choice, not a requirement to remain inactive after every lesson, and effects should not be equated entirely with prevention of interference.

Protect attention and adequate sleep

A memory cannot be retrieved reliably if the material was never adequately encoded. Reduce competing tasks when first learning similar information. For a separate evidence review of multiple concurrent media streams, see Media Multitasking: What It Is and How It Affects Attention, Memory, and Performance. Sleep can also influence encoding and retention, but sleep-dependent consolidation has its own mechanisms and canonical article: Sleep and Memory: Consolidation, Learning, and Sleep Loss.

Interference vs. decay, retrieval failure, and other kinds of forgetting

An interference explanation points to other learned material that disrupts a target. A time-based or decay explanation attributes change to processes correlated with the passage of time or disuse. An inadequate-encoding explanation points to information that was never established reliably. A retrieval-cue explanation emphasizes the failure of current cues to recover an otherwise available memory. Real experiments may contain more than one influence, and the accounts need not be mutually exclusive across tasks.

Retroactive interference also differs from the misinformation effect, where later misleading information can alter reports about an earlier event and raise questions about suggestion, source attribution, and reconstruction. It differs from retrieval-induced forgetting, which concerns the effect of selectively retrieving some information on related unpracticed items. It differs from directed forgetting, where instructions to remember or forget information change later performance. These effects belong within the broader psychology of memory but have their own definitions and experimental designs.

Interference is sometimes called an explanation of forgetting, but scientists increasingly ask where in the process the cost is produced. A performance deficit can emerge during new encoding, the maintenance of an association, consolidation, or final retrieval. Saying that the answer was “overwritten” skips that distinction. Modern work on reminding and integration shows that encountering conflicting information can sometimes strengthen access to an older association rather than simply weaken it.

Common myths about proactive and retroactive interference

Myth: Proactive interference is caused by new memories and retroactive interference is caused by old memories. The directions are the reverse: proactive means earlier learning affects a later target, while retroactive means later learning affects an earlier target.

Myth: Similar information must always harm memory. Similarity can create competitors, facilitate learning through shared structure, or prompt reminding and integration. The test and whether a change was noticed determine much of the outcome.

Myth: A wrong answer proves that a memory was erased. An intrusion demonstrates that a competitor was produced; it does not reveal whether the original representation has been destroyed. Recognition and context-sensitive retrieval can show retained information even when immediate free recall fails.

Myth: Interference studies prove forgetting is always caused by competing memories. Interference is strongly established in many paradigms, but human memory also depends on attention, encoding, consolidation, available cues, health, and the specific retention test.

Myth: Memory games can eliminate interference in daily life. Gains on a trained task do not automatically imply far transfer to school, work, or independent functioning. Practical techniques should be evaluated against the outcomes they claim to improve.

Clinical boundaries: when an everyday lapse needs evaluation

Ordinary memory interference is a feature of cognitive performance, not a psychiatric or neurological diagnosis. Confusing old and new passwords, addresses, or terminology is common enough to be understandable in the context of routine learning. A single interference-like mistake cannot establish dementia, ADHD, dissociation, a memory disorder, or an underlying brain disease.

If memory changes are persistent, progressive, markedly different from a person's usual functioning, or disrupt daily independence, a qualified clinician can review the pattern, associated symptoms, medications, sensory factors, sleep, mood, and relevant medical history. A screening measure may help identify whether additional assessment is appropriate; it is not a diagnosis in isolation. Sudden confusion or memory change with other acute neurological symptoms requires urgent medical evaluation.

Research on proactive and retroactive interference can inform cognitive assessment, but isolated scores are sensitive to instructions, age, education, language, sensory accessibility, and test design. Laboratory group findings cannot be converted into a personal clinical label without a validated evaluation framework.

Frequently asked questions

What is proactive interference in simple terms?

Proactive interference happens when something learned earlier makes it harder to remember something learned later. The old address coming to mind when you need the current address is a familiar example. To establish the effect scientifically, researchers compare performance with conditions that reduce prior competition.

What is retroactive interference in simple terms?

Retroactive interference happens when newer learning makes earlier information harder to remember. A recently learned address interfering with recall of an older address is an example when the older address is the target.

How can I tell which kind of interference is happening?

First identify what the person is trying to remember. If earlier learning gets in the way of that target, the interference is proactive. If later learning gets in the way of that target, it is retroactive. When the learning histories are unclear, a single mistake may not allow a confident classification.

What is the easiest way to remember the prefixes?

Proactive points forward: old learning interferes with newer information. Retroactive points backward: new learning interferes with older information. The memory being tested anchors the direction.

Can both occur with the same two memories?

Yes. An old and a new phone number can each interfere with retrieval of the other, depending on which one is requested. A given experiment may still show only one direction or a different degree of interference because learning strength, timing, and source cues are unequal.

Why does similar material cause more interference?

Related information can share retrieval cues, possible responses, and contexts. The same question may activate several answers. Research also shows that detecting changes and remembering the order of related episodes can reduce or even reverse some interference effects.

Is proactive interference the same as proactive inhibition?

Historical memory studies often use “proactive inhibition” for a behavioral impairment caused by prior learning. Modern terminology frequently prefers “interference” because observing reduced recall does not by itself prove an active inhibitory process. When discussing a historical paper, retain its original label while interpreting its mechanisms with contemporary evidence.

Is retroactive interference the same as memory overwriting?

No universal overwriting mechanism is established by a retroactive interference effect. Some experimental results are consistent with retrieval competition, others implicate changes during learning or retention, and successful remembering of change can preserve both old and new information.

Does the forgetting curve prove interference?

Forgetting curves document how measured retention changes with time under particular conditions. They do not uniquely identify a causal mechanism. Underwood and later researchers showed why prior learning history and competing information must be considered when interpreting forgetting.

Can sleeping after studying prevent retroactive interference?

Adequate sleep often supports memory formation and consolidation, but it is not a guaranteed shield against learning-related interference. The effects of intervening waking activity, sleep timing, material, and the later test are intertwined. The dedicated sleep-and-memory evidence should be evaluated separately.

Does switching subjects during studying prevent interference?

Switching can change the degree of overlap between successive materials, but switching tasks also has cognitive costs and may interrupt focused understanding. Evidence for spaced practice and appropriate retrieval is stronger than a blanket rule to change subjects every few minutes.

Does interference increase with age?

Some tasks show age-related differences in susceptibility or source monitoring, but age effects depend on design, prior knowledge, strategy, and the importance of the remembered items. Research also shows that detecting changes can support performance in both younger and older adults. Interference errors alone do not indicate neurodegenerative disease.

How do psychologists measure proactive and retroactive interference?

Common methods include paired-associate learning, overlapping list-learning tasks, short-term trials that track proactive buildup and release, and measures of recall intrusions, accuracy, reaction time, and source discrimination. Controls distinguish competition from poorer attention, unequal learning, and testing artifacts.

Can interference ever help memory?

Additional information can prompt recall of an earlier episode and link old and new answers with a record of which came first. Research on reminding and recollection of change has documented facilitation under specific laboratory conditions. Whether that helps in everyday learning depends on deliberately encoding the difference between versions.

References

Cepeda, N. J., Pashler, H., Vul, E., Wixted, J. T., & Rohrer, D. (2006). Distributed practice in verbal recall tasks: A review and quantitative synthesis. Psychological Bulletin, 132(3), 354–380. https://doi.org/10.1037/0033-2909.132.3.354

Cox, S. W., Kelley, C. M., Antony, J. W., & Wahlheim, C. N. (2026). Test delay and change awareness moderate retroactive and proactive memory effects. Memory & Cognition. https://doi.org/10.3758/s13421-026-01903-4

Jacoby, L. L., Wahlheim, C. N., & Kelley, C. M. (2015). Memory consequences of looking back to notice change: Retroactive and proactive facilitation. Journal of Experimental Psychology: Learning, Memory, and Cognition, 41(5), 1282–1297. https://doi.org/10.1037/xlm0000123

Karpicke, J. D., & Roediger, H. L., III. (2008). The critical importance of retrieval for learning. Science, 319, 966–968. https://doi.org/10.1126/science.1152408

Keppel, G., & Underwood, B. J. (1962). Proactive inhibition in short-term retention of single items. Journal of Verbal Learning and Verbal Behavior, 1(3), 153–161. https://doi.org/10.1016/S0022-5371(62)80023-180023-1)

Kliegl, O., & Bäuml, K.-H. T. (2020). Buildup and release from proactive interference—Cognitive and neural mechanisms. Neuroscience & Biobehavioral Reviews. https://doi.org/10.1016/j.neubiorev.2020.10.028

Kliegl, O., & Bäuml, K.-H. T. (2021). The mechanisms underlying interference and inhibition: A review of current behavioral and neuroimaging research. Brain Sciences, 11(9), 1246. https://doi.org/10.3390/brainsci11091246

Mawson, R. D., & Kang, S. H. K. (2025). The distributed practice effect on classroom learning: A meta-analytic review of applied research. Behavioral Sciences, 15(6), 771. https://doi.org/10.3390/bs15060771

McGeoch, J. A., & McDonald, W. T. (1931). Meaningful relation and retroactive inhibition. The American Journal of Psychology, 43(4), 579–588. https://doi.org/10.2307/1415159

Murphy, D. H., & Castel, A. D. (2022). Differential effects of proactive and retroactive interference in value-directed remembering for younger and older adults. Psychology and Aging, 37(7), 787–799. https://doi.org/10.1037/pag0000707

Underwood, B. J. (1957). Interference and forgetting. Psychological Review, 64(1), 49–60. https://doi.org/10.1037/h0044616

Wahlheim, C. N., & Jacoby, L. L. (2013). Remembering change: The critical role of recursive remindings in proactive effects of memory. Memory & Cognition, 41(1), 1–15. https://doi.org/10.3758/s13421-012-0246-9

Wimber, M., Alink, A., Charest, I., Kriegeskorte, N., & Anderson, M. C. (2015). Retrieval induces adaptive forgetting of competing memories via cortical pattern suppression. Nature Neuroscience, 18, 582–589. https://doi.org/10.1038/nn.3973

Psychological Encyclopedia