Retrieval savings with nonidentical elements: The case of simple addition and subtraction

The identical elements (IE) theory of fact representation (Rickard, 2005) proposes that memorized facts that are composed of identical elements (e.g., 6 × 8 = 48 and 8 × 6 = 48) share a common representation in memory, whereas facts with nonidentical elements (e.g., 6 × 8 = 48 and 48 ÷ 8 = 6) are represented separately in memory. The IE model has been successfully applied to the transfer of practice in simple multiplication and division, in transition from procedure-based to retrieval-based performance, and in cued episodic recall. In the present article, we examined the effects of practicing simple addition problems (e.g., 3 + 6 = 9) on the performance of corresponding subtraction problems (9 − 6 = 3), and vice versa. According to IE theory, there should be no transfer of retrieval savings between addition and subtraction facts if performance is based on discrete IE fact representations. Cross-operation response time savings were observed, however, for both small, well-memorized problems (e.g., practice 3 + 2, test 5 − 2) and larger problems (6 + 8, 14 − 6), and they were statistically robust when trials that were self-reported as direct retrieval were analyzed. The transfer of retrieval practice savings between facts with nonidentical elements challenges IE theory as a comprehensive model of transfer in memory retrieval.     

The organization of information retrieved from situation models

The organization of information when it is retrieved from situation models was explored using recognition and recall tests. A fan effect paradigm was used to assess organization in recognition and a clustering measure was used in recall. People memorized either object-location facts (e.g., “The pay phone is in the city hall”) or person/small location facts (e.g., “The banker is on the witness stand”). For object-location facts, a location-based organization was observed in both recall and recognition. However, for person/small location facts, a location-based organization was observed for recall, and a person-based organization was observed for recognition. Thus, the observed organization was flexible depending on the retrieval task.     

Selective memory retrieval can impair and improve retrieval of other memories

Research from the past decades has shown that retrieval of a specific memory (e.g., retrieving part of a previous vacation) typically attenuates retrieval of other memories (e.g., memories for other details of the event), causing retrieval-induced forgetting. More recently, however, it has been shown that retrieval can both attenuate and aid recall of other memories (K.-H. T. B?uml & A. Samenieh, 2010). To identify the circumstances under which retrieval aids recall, the authors examined retrieval dynamics in listwise directed forgetting, context-dependent forgetting, proactive interference, and in the absence of any induced memory impairment. They found beneficial effects of selective retrieval in listwise directed forgetting and context-dependent forgetting but detrimental effects in all the other conditions. Because context-dependent forgetting and listwise directed forgetting arguably reflect impaired context access, the results suggest that memory retrieval aids recall of memories that are subject to impaired context access but attenuates recall in the absence of such circumstances. The findings are consistent with a 2-factor account of memory retrieval and suggest the existence of 2 faces of memory retrieval.     

Focused memory search in fact retrieval

Several studies of fact retrieval have shown that the more facts a person learns about a concept, the longer it takes him or her to retrieve any of these facts. This result has been interpreted to mean that retrieval of a fact about a concept involves a search of all facts stored in memory with that concept. In the present study, it is suggested that retrieval involves not an unfocused search of all facts stored with a concept, but rather a focused memory search that examines relevant stored facts and ignores irrelevant information. This argument is supported by three experiments in which subjects first learned simple facts (e.g., “The banker likes horses”) and then made speeded true-false decisions for test probes le.g., “The banker likes elephants”). Specifically, results suggest that facts stored with a concept may be organized into subsets. For example, a person’s knowledge about Richard Nixon might be organized into subsets concerning Nixon’s resignation, his trips to China, his family, and so on. The data further suggest that a person attempting to retrieve a fact about a concept (e.g., the name of Nixon’s wife) may simply decide which subset is most likely to contain the desired fact (e.g., the subset concerning Nixon’s family) and search that subset. If the sought-for fact is found in this subset, the search process terminates. If, however, the desired information is not located, other subsets of facts may be searched before the retrieval attempt is given up. The notion that memory search focuses on relevant stored facts and ignores irrelevant information may help to explain why experts (i.e., people who know a large number of facts about a topic) do not experience great difficulty in retrieving facts in their areas of expertise.     

POSITIVE EMOTIONS ENHANCE RECALL OF PERIPHERAL DETAILS

Emotional arousal and negative affect enhance recall of central aspects of an event. However, the role of discrete emotions in selective memory processing is understudied. Undergraduates were asked to recall and rate autobiographical memories of eight emotional events. Details of each memory were rated as central or peripheral to the event. Significance of the event, vividness, reliving and other aspects of remembering were also rated for each event. Positive affect enhanced recall of peripheral details. Furthermore, the impairment of peripheral recall was greatest in memories of anger, not of fear. Reliving the experience at retrieval was negatively correlated with recall of peripheral details for some emotions (e.g., anger) but not others (e.g., fear), irrespective of similarities in affect and intensity. Within individuals, recall of peripheral details was correlated with less belief in the memory's accuracy and more likelihood to recall the memory from one's own eyes (i.e., a field perspective).     

Semantic-memory sources of episodic retrieval failure

In a cued-recall paradigm, retrieval blocking was investigated as a source of episodic retrieval failure. Each unrelated-interference (UR-I) word pair (e.g., “nurse-dollar”) had its own “competitive alternative” (e.g., “doctor’), which not only was strongly related to the cue word, but also possessed the same first two letters and final letter as did the target word. None of the unrelated-control (UR-C) word pairs (e.g., “clock-dollar”) had such an alternative. Cued recall substantially increased from the cue-word-only (e.g., “nurse- ”) to the three-letters-also cue condition (e.g., “nurse-do___r”) for the UR-C but not for the UR-I word pairs. Instead, subjects frequently reported the competitive alternatives in place of the UR-I target words in the three-letters-also cue condition. It was suggested that, relying on the primary plausibility judgment, subjects falsely accepted the competitive alternatives while the UR-I target words were blocked from retrieval by the potent retrieval of these plausible alternatives.     

Positive emotions enhance recall of peripheral details

Emotional arousal and negative affect enhance recall of central aspects of an event. However, the role of discrete emotions in selective memory processing is understudied. Undergraduates were asked to recall and rate autobiographical memories of eight emotional events. Details of each memory were rated as central or peripheral to the event. Significance of the event, vividness, reliving and other aspects of remembering were also rated for each memory. Positive affect enhanced recall of peripheral details. Furthermore, the impairment of peripheral recall was greatest in memories of anger, not of fear. Reliving the experience at retrieval was negatively correlated with recall of peripheral details for some emotions (e.g., anger) but not others (e.g., fear), irrespective of similarities in affect and intensity. Within individuals, recall of peripheral details was correlated with less belief in the memory's accuracy and more likelihood to recall the memory from one's own eyes (i.e., a field perspective).     

Encoding specificity revisited: the role of semantics.

Three experiments examined the effects of semantic characteristics of word pairs on memory using the encoding specificity paradigm. The paradigm involved four phases: (a) an encoding phase to relate cues and targets, (b) a phase in which words were generated to new cues, (c) a phase for recognition of generated targets, and (d) a cued-recall phase using the original encoding cues. Encoding pairs were classified a priori as either semantically similar (e.g., alluring-PRETTY), semantically contrasting (e.g., drab-PRETTY), or semantically unrelated (e.g., sore-PRETTY). Generation pairs were classified a priori as either semantically similar (e.g., beautiful-PRETTY) or semantically contrasting (e.g., ugly-PRETTY). For recall, the results showed that both the semantic relations between the encoding cue and target and the reprovision of the encoding cue at retrieval were important factors. In the case of recognition, however, both the semantic congruence between the encoding and generation contexts and the amount of semantic elaboration provided by the encoding context were important factors.     

Providing corrective feedback during retrieval practice does not increase retrieval-induced forgetting

Recalling a subset of studied materials can impair subsequent retrieval of related, nontested materials. In two experiments, we examined the influence of providing corrective feedback (no feedback, immediate feedback, delayed feedback) during retrieval practice on this retrieval-induced forgetting effect. Performance was assessed with category cued recall (e.g., recall all exemplars studied under Weather), category-and-stem cued recall (e.g., Weather–B___), and recognition. We report a dissociation between the effects of feedback on memory of the tested materials and the nontested materials. Whereas providing immediate or delayed feedback (compared to no feedback) improved recall and recognition of the tested items, it had no influence on retrieval-induced forgetting. These results are consistent with the inhibition account of retrieval-induced forgetting. From an applied perspective, this finding is encouraging for students and educators who use testing to foster learning.     

Enhancing individual and collaborative eyewitness memory with category clustering recall

Most crimes have multiple eyewitnesses. The police typically interview co-witnesses separately. In time-sensitive investigations, this could slow down evidence accumulation. Having co-witnesses collaboratively recall a crime could potentially expedite evidence accumulation. However, past research shows that collaborative group members often have conflicting retrieval strategies that disrupt each other, degrading overall recall. This cost could potentially be overcome by aligning group members’ retrieval strategies with category clustering recall (CCR), which is a retrieval strategy where information is recalled from a series of forensically relevant categories (e.g., recalling the protagonists’ appearance, then actions). This study examined the costs and benefits of collaborative eyewitness memory by having collaborative pairs of strangers, nominal pairs (i.e., two individuals whose recall is pooled) and lone individuals watch a crime and recall it using free recall or CCR. The collaborative pairs recalled the crime faster than the nominal pairs. They also recalled more correct information than individuals but less than nominal pairs, irrespective of the retrieval method. There is therefore a speed-recall completeness trade-off when collaborative groups recall crimes. Importantly, all participants recalled more correct information when using CCR. This provides initial evidence suggesting that CCR is superior to free recall. Further research examining CCR’s benefits is recommended.     

Proactive interference and cuing effects in short-term cued recall: Does foil context matter?

Tehan and Humphreys's (1995, 1996) short-term cued recall paradigm showed that recall in short-term memory is cue driven. In critical trials, the participants studied two blocks of four words each and were required to forget the first block while remembering the second block. A foil in the first block (e.g., orange) was related to a target (e.g., carrot) in the second block. Proactive interference (PI) was evident when a retrieval cue was used that subsumed the foil and the target (e.g., type of juice), but not when a cue was used that subsumed only the target (e.g., type of vegetable). Four experiments were performed to examine the extent to which contextual organization in the foil block would enhance or diminish the foil's efficacy in creating PI. A novel condition was included in which the words in the foil block were studied in a phonologically related context but the target was cued semantically, and vice versa with a semantic context and phonological cue. There were no differences in recall accuracy between conditions with and without contextual organization, but reliable increases in foil intrusions were observed when contextual organization was present. Contextual organization enhanced the foil, rather than diminished it, but the strengthened foil generated PI only when the cue subsumed the foil and the target and had no effect when the cue subsumed only the target. The results are consistent with a cue-driven retrieval interpretation of short-term recall.     

Collaborative memory and part-set cueing impairments: the role of executive depletion in modulating retrieval disruption

When people are exposed to a subset of previously studied list items they recall fewer of the remaining items compared to a condition where none of the studied items is provided during recall. This occurs both when the subset of items is provided by the experimenter (i.e., the part-set cueing deficit in individual recall) and when they are provided during the course of a collaborative discussion (i.e., the collaborative inhibition effect in group recall). Previous research has identified retrieval disruption as a common mechanism underlying both effects; however, less is known about the factors that may make individuals susceptible to such retrieval disruption. In the current studies we tested one candidate factor: executive control. Using an executive depletion paradigm we directly manipulated an individual's level of executive control during retrieval. Results revealed no direct role of executive depletion in modulating retrieval disruption. In contrast, executive control abilities were indirectly related to retrieval disruption through their influence at encoding. Together these results suggest that executive control des not directly affect retrieval disruption at the retrieval stage, and that the role of this putative mechanism may be limited to the encoding stage.     

Auditory feedback and memory for music performance: Sound evidence for an encoding effect

Research on the effects of context and task on learning and memory has included approaches that emphasize processes during learning (e.g., Craik & Tulving, 1975) and approaches that emphasize a match of conditions during learning with conditions during a later test of memory (e.g., Morris, Bransford, & Franks, 1977; Proteau, 1992; Tulving & Thomson, 1973). We investigated the effects of auditory context on learning and retrieval in three experiments on memorized music performance (a form of serial recall). Auditory feedback (presence or absence) was manipulated while pianists learned musical pieces from notation and when they later played the pieces from memory. Auditory feedback during learning significantly improved later recall. However, auditory feedback at test did not significantly affect recall, nor was there an interaction between conditions at learning and test. Auditory feedback in music performance appears to be a contextual factor that affects learning but is relatively independent of retrieval conditions.     

The development of retrieval strategies in young children

Two incidental memory tasks were given to 3.5–6.5 yr old children to test for an age increase in the tendency to use a simple indirect retrieval strategy when direct retrieval efforts do not suffice. In both tasks, pictures of people were paired with very closely associated toy objects (e.g., farmer—toy tractor), and the indirect retrieval strategy consisted of thinking to use one member of the pair as a cue to the recall of the other, e.g., turning over the visible but facedown pictures and using them as retrieval cues for the toys. Support for the predicted age trend was obtained in one of the two tasks. It was suggested that the development of retrieval skills in children may show some parallels with that of storage skills.     

Inferences about predictable events

If someone falls off of a 14th story roof, very predictably death will result. The conditions under which readers appear to infer such predictable outcomes were examined with three different retrieval paradigms: immediate recognition test, cued recall, and priming in word recognition. On immediate test, responses to a word representing the implicit outcome (e.g., dead) were slow, but on delayed test these responses were slow or inaccurate only when primed by an explicitly stated word. However, the word expressing the predictable outcome did function as an effective recall cue. Results suggest that readers encode these inferences into memory only minimally, but that they can make use of a cue word that represents the inference (e.g., dead) both at the time of an immediate test and in delayed cued recall.     

Fan effects reveal position-specific numerical concepts.

We examined associative interference (i.e., fan) effects to determine if the numerical concepts mediating numerical fact retrieval can be position specific. Participants memorized 15 "diamond arithmetic" facts (e.g., 3 [symbol: see text] 5 = 97; Whalen, 1997) involving five different operands. Ignoring operand position (i.e., left vs. right), each operand appeared equally often across items (i.e., position-independent fan was constant). In contrast, position-specific fan values varied across items (e.g., 2 appeared five times as the left operand, but once in the right position; 3 appeared four times as the left operand, and twice as the right operand, etc). Thus, we expect a fan effect only if the concepts activated by arithmetic operands are position specific. Results indicated that position-specific fan was an excellent predictor of trials to criterion, error rate, and latency. The concepts mediating number fact retrieval can be position specific.     

Does remembering emotional items impair recall of same-emotion items?

In the part-set cuing effect, cuing a subset of previously studied items impairs recall of the remaining noncued items. This experiment reveals that cuing participants with previously-studied emotional pictures (e.g., fearevoking pictures of people) can impair recall of pictures involving the same emotion but different content (e.g., fear-evoking pictures of animals). This indicates that new events can be organized in memory using emotion as a grouping function to create associations. However, whether new information is organized in memory along emotional or nonemotional lines appears to be a flexible process that depends on people’s current focus. Mentioning in the instructions that the pictures were either amusement- or fear-related led to memory impairment for pictures with the same emotion as cued pictures, whereas mentioning that the pictures depicted either animals or people led to memory impairment for pictures with the same type of actor.     

Collaborative memory and part-set cueing impairments: The role of executive depletion in modulating retrieval disruption

When people are exposed to a subset of previously studied list items they recall fewer of the remaining items compared to a condition where none of the studied items is provided during recall. This occurs both when the subset of items is provided by the experimenter (i.e., the part-set cueing deficit in individual recall) and when they are provided during the course of a collaborative discussion (i.e., the collaborative inhibition effect in group recall). Previous research has identified retrieval disruption as a common mechanism underlying both effects; however, less is known about the factors that may make individuals susceptible to such retrieval disruption. In the current studies we tested one candidate factor: executive control. Using an executive depletion paradigm we directly manipulated an individual's level of executive control during retrieval. Results revealed no direct role of executive depletion in modulating retrieval disruption. In contrast, executive control abilities were indirectly related to retrieval disruption through their influence at encoding. Together these results suggest that executive control des not directly affect retrieval disruption at the retrieval stage, and that the role of this putative mechanism may be limited to the encoding stage.     

A neuropsychological study of fact memory and source amnesia

We investigated the ability of amnesic patients to learn new facts (e.g., Angel Falls is located in Venezuela) and also to remember where and when the facts were learned (i.e., source memory). To assess the susceptibility of fact and source memory to retrograde amnesia, patients prescribed electroconvulsive therapy were presented facts prior to the first treatment and were tested after their second treatment. All amnesic patients exhibited marked fact memory impairment. In addition, some amnesic patients exhibited source amnesia (i.e., they recalled a few facts but then could not remember where or when those facts had been learned). Source amnesia was unrelated to the severity of the memory deficit itself, because patients who exhibited source amnesia recalled as many facts as the patients who did not. These results show that the deficit in amnesia includes an impairment in acquiring and retaining new facts. Source amnesia can also occur, but it is dissociable from impaired recall and recognition and appears to reflect difficulty in remembering the specific context in which information is acquired. The findings are discussed in terms of their significance for how memory is organized.