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Here, we present two case studies of extremely long-term retention. In the first, Richard C. Atkinson (RCA) had learned word sequences during experiments for his dissertation. Sixty-seven years later, RCA relearned the same words either in the original order or in a scrambled order. RCA reported no conscious awareness that the words were those used in the dissertation, but his relearning was considerably better for the words in the original order. In the second case study, Denis Cousineau had searched displays of objects for the presence of a target. The targets and foils had been novel at the beginning of training, and his search rate improved markedly over about 70 sessions. After 22 years, retraining showed retention of much of this gain in rate of search, and the rate was markedly faster than search for new objects with the same structure as the trained set. We consider interpretations of these case studies for our understanding of long-term retention.

Directed forgetting is a laboratory task in which subjects are explicitly cued to forget certain items and remember others. Volitional control over the contents of memory has been used to study clinical disorders, with successful intentional control of memory being a hallmark of a healthy mind. Yet the degree of volitional forgetting over the content of visual long-term memory is unclear when compared to words. Different kinds of visual stimuli (e.g., abstract symbols, line drawings, scenes) may not equally be susceptible to voluntary control in memory, and intentional forgetting studies have shown both twice as much forgetting of pictures compared to words (think/no-think task) and half as much forgetting of pictures compared to words (directed forgetting task). In the present study, we systematically test volitional control over pictures of everyday objects using item-method directed forgetting procedures. We find that subjects are able to intentionally prioritize memory for pictures cued as to be remembered over pictures cued to be forgotten. Here we show that directed forgetting effects are observed using pictures of everyday objects (albeit to a weaker extent compared to directed forgetting of words), suggesting increased confidence for generalization of directed forgetting literature to real-world applications. However, we caution clinical applications of intentional memory control until the underlying direction causing this effect (upregulation of remember-cued items or downregulation of forget-cued items) is known.

Previous research from our lab has shown that recognizing an object stored in visual long-term memory leads to the forgetting of related objects. Here we ask whether context, an integral aspect to modern models of memory, plays a role in induced forgetting. We manipulated the activated context at test, both externally (e.g., changes in testing room) and internally (e.g., 1 hr and 24 hr later). We found that only interfering with the ability to internally reinstate context after 24 hr eliminated induced forgetting. Thus, we demonstrate that mental context reinstatement plays a role in induced forgetting and specify that models of memory should incorporate internal context reinstatement as an underlying factor of forgetting. We also propose a process model of induced forgetting, discuss limitations of laboratory-based memory tasks, and offer a new term, induced suppression, to collectively describe this robust phenomenon. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Recognition-induced forgetting, whereby the recognition of targeted memories induces the forgetting of related memories, results from the recognition of old objects and rejection of new objects. Here we asked whether both these tasks are necessary to induce forgetting. Our unique design allowed us to isolate the recognition of old objects from the rejection of new objects by presenting subjects with only new objects, only old objects, and a mixture of both in separate conditions of an old-new recognition task. In all three conditions, we successfully induced forgetting. The magnitude of forgetting was statistically indistinguishable across all three conditions, showing that recognition of old objects and rejection of new objects are each building blocks of forgetting. These findings pinpoint both recognition and rejection as mechanisms underlying recognition-induced forgetting and demonstrate the ubiquity of this forgetting effect.

Recognition-induced forgetting is a within-category forgetting effect that results from accessing memory representations. Advantages of this paradigm include the possibility of testing the memory of young children using visual objects before they can read, the testing of multiple types of stimuli, and use with animal models. Yet it is unknown whether just episodic memory tasks (Have you seen this before?) or also semantic memory tasks (Is this bigger than a loaf of bread?) will lead to this forgetting effect. This distinction will be critical in establishing a model of recognition-induced forgetting. Here, we implemented a design in which both these tasks were used in the same experiment to determine which was leading to recognition-induced forgetting. We found that episodic memory tasks, but not semantic memory tasks, created within-category forgetting. These results show that the difference-of-Gaussian forgetting function of recognition-induced forgetting is triggered by episodic memory tasks and is not driven by the same underlying memory signal as semantic memory.

Recognition-induced forgetting is the category-specific forgetting of pictures that occurs when a subset of a category of pictures is recognized, leading to forgetting of the remaining pictures. We have previously shown that recognition-induced forgetting does not operate over categories created by temporal relationships, suggesting that this effect does not operate over episodic memory representations. Here we systematically tested whether schematically related categories of pictures are immune to recognition-induced forgetting. We found that sufficiently weak schematically related memories are vulnerable to recognition-induced forgetting. These results offer an alternative interpretation for evidence that recognition-induced forgetting does not operate over episodic memory representations. Evidence that the strength of schematic grouping modulates forgetting supports a model of recognition-induced forgetting in which the key determinant of forgetting is moderate activation. This is the first demonstration that recognition-induced forgetting operates over perceptually distinct objects, demonstrating the ubiquity of such forgetting.

Here we employ a novel analysis to address the question: what causes induced forgetting of pictures? We use baseline memorability as a measure of initial memory strength to ask whether induced forgetting is due to (1) recognition practice damaging the association between the memory representation and the category cue used to activate the representation, (2) the updating of a memory trace by incorporating information about a memory probe presented during recognition practice to the stored trace, (3) inhibitory mechanisms used to resolve the conflict created when correctly selecting the practiced item activates competing exemplars, (4) a global matching model in which repeating some items will hurt memory for other items, or (5) falling into the zone of destruction, where a moderate amount of activation leads to the highest degree of forgetting. None of the accounts of forgetting tested here can comprehensively account for both the novel analyses reported here and previous data using the induced forgetting paradigm. We discuss aspects of forgetting theories that are consistent with the novel analyses and existing data, a potential solution for existing models, proposals for future directions, and considerations when incorporating memorability into models of memory.

Induced forgetting occurs when accessing an item in memory appears to harm memory representations of categorically related items. However, it is possible that the actual memory representations are unharmed. Instead, people may just change how they make decisions. Specifically, signal detection theory suggests this apparent forgetting may be due to participants shifting their decision criterion. Here, we used behavioral and electrophysiological measures to determine whether induced forgetting is truly due to changes in how items are represented or simply due to a shifting criterion. Participants' behavior and brain activity showed that induced forgetting was due to changes in the strength of the underlying representations, weighing against a criterion shift explanation of induced forgetting.

Recent evidence has shown that practice recognizing certain objects hurts memories of objects from the same category, a phenomenon called recognition-induced forgetting. In all previous studies of this effect, the objects have been related by semantic category (e.g., instances of vases). However, the relationship between objects in many real-world visual situations stresses temporal grouping rather than semantic relations (e.g., a weapon and getaway car at a crime scene), and temporal grouping is thought to cluster items in models of long-term memory. The goal of the present study was to determine whether temporally grouped objects suffer recognition-induced forgetting. To this end, we implemented a modified recognition-induced forgetting paradigm in which the objects were temporally clustered at study. Across four experiments, we found that recognition-induced forgetting occurred only when the temporally clustered objects were also semantically related. We conclude by discussing how these findings relate to real-world vision and inform models of memory.

Intentional forgetting refers to the attempt to marshal top-down control to purposefully forget, and has been demonstrated in the laboratory using directed forgetting paradigms. Here, we asked whether the mechanisms of top-down control can run in the opposite direction to prevent the forgetting of information; that is, can we actively resist unintentional forgetting? Recognition-induced forgetting is an unintentional forgetting effect in which accessing one memory leads to the forgetting of related memories. Just as intentional forgetting possesses intuitively appealing control over eliminating undesirable memories, resisting unintentional forgetting over desired memories would improve cognitive performance. We showed subjects a 9-min video to teach them about the recognition-induced forgetting paradigm and how recognition of certain objects unintentionally leads to forgetting of semantically related objects. After testing their comprehension of the video, we conducted a typical recognition-induced forgetting experiment and challenged the subjects to resist this form of unintentional forgetting. Despite their knowledge of the forgetting effect, and the challenge to subjects to resist the forgetting induced by the paradigm, recognition-induced forgetting persisted. These results show that knowledge of this unintentional forgetting phenomenon and the challenge to resist forgetting do not eliminate it, suggesting that it is cognitively impenetrable. Electronic supplementary material The online version of this article (10.1186/s41235-019-0180-5) contains supplementary material, which is available to authorized users.

A large body of literature agrees that accessing a target memory appears to trigger a difference-of-Gaussian memory activation pulse under which the target representation is activated and categorically flanking items are suppressed and forgotten. The nature of the underlying forgetting mechanism is far from settled, with support for several theories of forgetting. Here we argue the debate is partly fueled by different forgetting mechanisms underlying the forgetting of different memoranda. We capitalized on the unique aspect of the recognition-induced forgetting paradigm to test forgetting of both pictures and words in identical recognition-practice and restudy tasks. We found that memory for pictures and words followed different patterns of forgetting. Specifically, forgetting was retrieval specific for words, in that forgetting occurred only when words were recognized, and not when words were merely restudied. However, forgetting was not retrieval specific for pictures, in that forgetting occurred both when pictures were recognized as well as restudied. Further, patterns of forgetting operated along different category-level groupings for pictures and words. Words grouped along the superordinate level were susceptible to forgetting but pictures were not. The strength of this design is the ability to directly compare forgetting for different memoranda, establishing that patterns of forgetting are modality specific. These findings demonstrate that the mechanisms underlying forgetting may differ as a function of the particular memoranda, emphasizing the need for examining forgetting in long-term memory across modalities.

Summary Accessing memories is often accompanied by both positive and negative consequences. For example, practice recognizing some visual images held in memory can improve memory for the practiced images and hurt memory for related images (i.e., recognition-induced forgetting). However, visual stimuli have been shown to improve memory for older adults by decreasing false memories. This suggests that older adults may be immune to recognition-induced forgetting and that recognition practice may decrease susceptibility to intrusion errors. We first tested the hypothesis that older adults are immune to recognition-induced forgetting. We found older adults exhibit recognition-induced forgetting. Next, we tested the hypothesis that recognition practice decreases older adult's rates of intrusion errors. We found lower intrusion errors for novel objects from practiced categories. This represents a generalizable learning effect; practice recognizing a target object (e.g., your pill bottle) improves the rejection of new lures (e.g., identifying the pill bottle that is not yours).Copyright © 2016 John Wiley & Sons, Ltd.

A popular educational method when teaching children new information is encouraging children to activate previously learned information held in long-term memory. A potential downside of this practice is the considerable evidence that there are negative consequences of accessing long-term memory representations. Specifically, it has been shown that accessing information in long-term memory can actually impair related memories. This impairment has classically been demonstrated with verbal material (i.e., retrieval-induced forgetting) and more recently with visual material in adults (i.e., recognition-induced forgetting). The goal of the present study was to examine whether recognition-induced forgetting exists in visual long-term memory for children aged 6–10 years old, the age at which retrieval-induced forgetting appears to emerge. To this end, we presented children with an abbreviated, age-appropriate recognition-induced forgetting paradigm. If children suffer recognition-induced forgetting, practicing a ...

Despite more than a century of evidence that long-term memory for pictures and words are different, much of what we know about memory comes from studies using words. Recent research examining visual long-term memory has demonstrated that recognizing an object induces the forgetting of objects from the same category. This recognition-induced forgetting has been shown with a variety of everyday objects. However, unlike everyday objects, faces are objects of expertise. As a result, faces may be immune to recognition-induced forgetting. However, despite excellent memory for such stimuli, we found that faces were susceptible to recognition-induced forgetting. Our findings have implications for how models of human memory account for recognition-induced forgetting as well as represent objects of expertise and consequences for eyewitness testimony and the justice system.

The serial and spatially extended nature of many real-world visual tasks suggests the need for control over the content of visual working memory (VWM). We examined the management of VWM in a task that required participants to prioritize individual objects for retention during scene viewing. There were 5 principal findings: (a) Strategic retention of task-relevant objects was effective and was dissociable from the current locus of visual attention; (b) strategic retention was implemented by protection from interference rather than by preferential encoding; (c) this prioritization was flexibly transferred to a new object as task demands changed; (d) no-longer-relevant items were efficiently eliminated from VWM; and (e) despite this level of control, attended and fixated objects were consolidated into VWM regardless of task relevance. These results are consistent with a model of VWM control in which each fixated object is automatically encoded into VWM, replacing a portion of the content in VWM. However, task-relevant objects can be selectively protected from replacement.

Attention operates to select both spatial locations and perceptual objects. However, the specific mechanism by which attention is oriented to objects is not well understood. We examined the means by which object structure constrains the distribution of spatial attention (i.e., a “grouped array”). Using a modified version of the Egly et al. object cuing task, we systematically manipulated within-object distance and object boundaries. Four major findings are reported: 1) spatial attention forms a gradient across the attended object; 2) object boundaries limit the distribution of this gradient, with the spread of attention constrained by a boundary; 3) boundaries within an object operate similarly to across-object boundaries: we observed object-based effects across a discontinuity within a single object, without the demand to divide or switch attention between discrete object representations; and 4) the gradient of spatial attention across an object directly modulates perceptual sensitivity, implicating a relatively early locus for the grouped array representation.

As researchers who study working memory, we often assume that participants keep a representation of an object in working memory when we present a cue that indicates that the object will be tested in a couple of seconds. This intuitively accounts for how well people can remember a cued object, relative to their memory for that same object presented without a cue. However, it is possible that this superior memory does not purely reflect storage of the cued object in working memory. We tested the hypothesis that cues presented during a stream of objects, followed by a short retention interval and immediate memory test, can change how information is handled by long-term memory. We tested this hypothesis by using a family of frontal event-related potentials believed to reflect long-term memory storage. We found that these frontal indices of long-term memory were sensitive to the task relevance of objects signaled by auditory cues, even when the objects repeated frequently, such that proactive interference was high. Our findings indicate the problematic nature of assuming process purity in the study of working memory, and demonstrate that frequent stimulus repetitions fail to isolate the role of working memory mechanisms.

Retrieval-induced forgetting is a phenomenon in which groups of stimuli are initially learned, but then a subset of those stimuli are subsequently remembered via retrieval practice, causing the forgetting of the other initially learned items. This phenomenon has almost exclusively been studied using linguistic stimuli. The goal of the present study was to determine whether our memory for simultaneously learned visual stimuli was subject to a similar type of memory impairment. Participants were shown real-world objects, then they practiced recognizing a subset of these remembered objects, and finally their memory was tested for all learned objects. We found that practicing recognition of a subset of items resulted in forgetting of other objects in the group. However, impaired recognition did not spread to new objects belonging to the same category. Our findings have important implications for how our memories operate in real-world tasks, where remembering one object or aspect of a visual scene can cause us to forget other information encoded at the same time.

Can we entirely erase a temporary memory representation from mind? This question has been addressed in several recent studies that tested the specific hypothesis that a representation can be erased from visual working memory based on a cue that indicated that the representation was no longer necessary for the task. In addition to behavioral results that are consistent with the idea that we can throw information out of visual working memory, recent neurophysiological recordings support this proposal. However, given the infinite capacity of long-term memory, it is unclear whether throwing a representation out of visual working memory really removes its effects on memory entirely. In this paper, we advocate for an approach that examines our ability to erase memory representations from working memory, as well as possible traces that those erased representations leave in long-term memory.

In four experiments, we tested whether sustained visual attention is required for the selective maintenance of objects in visual working memory (VWM). Participants performed a color change-detection task. During the retention interval, a valid cue indicated the item that would be tested. Change-detection performance was higher in the valid-cue condition than in a neutral-cue control condition. To probe the role of visual attention in the cuing effect, on half of the trials, a difficult search task was inserted after the cue, precluding sustained attention on the cued item. The addition of the search task produced no observable decrement in the magnitude of the cuing effect. In a complementary test, search efficiency was not impaired by simultaneously prioritizing an object for retention in VWM. The results demonstrate that selective maintenance in VWM can be dissociated from the locus of visual attention.