Depth of processing and memory organization

Summary The study examined the idea that the organization of information in memory varies depending on the depth of processing during input, as well as on the conditions for retrieval. Two types of memory organization are distinguished: Conceptual organization implies a hierarchical structure in which items are grouped according to a principled taxonomic system (e.g., cow — horse). Associative organization, in contrast, is based on direct links among the members of a group (e.g., cow — milk). Two experiments examined the propositions that conceptual relations require more effort to be encoded during learning and more effort to be utilized during remenbering than associative relations. In Experiment 1 a list of 28 words was used, which could be grouped into 14 conceptual categories or, alternatively, into 14 associative categories of two words each. The words were presented under either shallow or deep encoding conditions. Increased depth of encoding resulted in increased conceptual clustering but had little effect on amount of associative clustering. Similar amounts of associative and conceptual clustering were observed during early output positions, but conceptual clustering tended to increase with recall trials, suggesting that it might depend on the establishment of a retrieval schema. In Experiment 2, after memorizing a list of words, subjects recalled the words either with or without the requirement to perform a secondary task while recalling. Relative to the undisturbed recall condition, the secondary task condition indicated stronger associative than conceptual clustering. The results were seen to support the idea that different types of memory organization may become salient under different attentional conditions.     

The generality of the levels of processing hypothesis: An application to memory for chess positions

The generality of the levels of processing approach to memory was tested by using chess positions rather than words as stimuli. Experiment 1 compared recall following semantic orienting instructions (find the best move and determine which side has the advantage), formal orienting instructions (determine the number of pieces on light squares and the number of pieces on dark squares), and intentional learning instructions using 19 novice chess players as subjects. Formal orienting instructions produced poorer recall than did either semantic orienting or intentional learning instructions, which yielded similar levels of retention. These results were replicated in Experiment 2 with 16 tournament chess players. Chess rating correlated with recall .82 under semantic orienting instructions but only —.15 under formal orienting instructions. It was concluded that the levels of processing framework has applicability outside the area of verbal learning.     

The subjective organization of input and output events in memory

In order to study the organization of memory for self-performed actions, 80 participants were presented with 20 action phrases for ten consecutive study-test cycles. Enactment was manipulated both in the input phase and in the output phase by having participants say or enact the phrases during encoding and/or during testing. Enactment at input or output generally enhanced both the quantity and the accuracy of recall and also improved output monitoring. More important, subjective organization, as indexed by the tendency to recall the same two phrases successively across repeated recall tests, was significant for all conditions, even on the first pair of trials, and increased systematically with repeated study-test cycles. Enactment neither impaired nor enhanced the amount of organization, and in all conditions a positive correlation was obtained between recall and subjective organization. Some commonalities in the nature of memory organization were found across all conditions. The results suggest that enactment may lead to more differentiated memory traces, resulting in more accurate recall. Although subjective organization was clearly observed when enactment was involved, its contribution to the enhancement of recall deserves further examination. Received: 12 November 1997 / Accepted: 2 June 1998     

Perceptual and conceptual training mediate the verbal overshadowing effect in an unfamiliar domain

Describing memory for a nonverbal perceptual stimulus can impair recognition. This verbal overshadowing effect may occur when perceptual expertise exceeds verbal expertise, but previous evidence for this hypothesis has been strictly correlational. We conducted two experiments, exploring the relation between expertise and verbal overshadowing by manipulating perceptual and conceptual knowledge. Participants received perceptual training (categorizing mushrooms), conceptual training (lecture), or no training, then viewed a mushroom and described it or not. A recognition test followed. In Experiment 1, perceptual training increased susceptibility to verbalization relative to the no training condition. However, conceptual training did not insulate individuals from the verbal overshadowing effect. Experiment 2 was modified to enhance both forms of training. It replicated the finding that perceptual training increases vulnerability to verbal overshadowing, and indicated that, when sufficiently emphasized, verbalization may be useful following conceptual training. The results demonstrate the role that different forms of learning and expertise may play in mediating language influences on recognition memory.     

What colour is the car? Implicit memory for colour information in children

Three experiments were conducted to examine age-related differences in colour memory. In Experiment 1, preschool age and elementary school age children were given a conceptual test of implicit colour memory (a colour-choice task). They were presented with the names or achromatic versions of previously studied coloured line drawings and asked to select an appropriate colour. Significant priming could be demonstrated: The children chose the previously seen colours more often than was expected by chance. Equivalent priming was found for both versions (pictorial and verbal) suggesting that colour priming may be conceptually mediated. Moreover, colour priming proved to be age invariant. Experiment 2 replicated and extended this finding by using a wider age group (preschool, elementary school, and young adults) and by giving a perceptual implicit task (picture identification) in addition to a verbal colour-choice task. Colour did not affect priming in the perceptual task. Whereas priming showed no developmental change, agerelated improvements were observed on an explicit colour memory task that differed only in the test instructions from the implicit colour-choice task (Experiments 2 and 3). Taken together, the results suggest that implicit colour memory may be mediated by conceptual processes that are age invariant.     

The influence of levels of processing on recall from working memory and delayed recall tasks

Recent research in working memory has highlighted the similarities involved in retrieval from complex span tasks and episodic memory tasks, suggesting that these tasks are influenced by similar memory processes. In the present article, the authors manipulated the level of processing engaged when studying to-be-remembered words during a reading span task (Experiment 1) and an operation span task (Experiment 2) in order to assess the role of retrieval from secondary memory during complex span tasks. Immediate recall from both span tasks was greater for items studied under deep processing instructions compared with items studied under shallow processing instructions regardless of trial length. Recall was better for deep than for shallow levels of processing on delayed recall tests as well. These data are consistent with the primary-secondary memory framework, which suggests that to-be-remembered items are displaced from primary memory (i.e., the focus of attention) during the processing phases of complex span tasks and therefore must be retrieved from secondary memory.     

Signing enhances memory like performing actions

In three experiments, we investigated the influence of the overt performance of signs on memory. Deaf and hearing participants studied lists of action phrases (Experiment 1) or nouns (Experiment 2) under standard verbal instruction, under the instructions to sign the verbal phrase, to symbolically perform the denoted action, or to carry out a prototypical action corresponding to each noun. Higher recall and recognition performances were observed when actions were performed than in the verbal encoding condition, and signing was as effective for memory as was enactment. Thus, overt signing can induce an enactment effect. In contrast, Experiment 3 demonstrated that performing an unrelated action did not. A unique but unrelated action was not memory efficient.     

Does motor encoding enhance relational information?

Summary Three experiments investigated whether learning action phrases by enacting the denoted action enhances organization or not. In the first experiment it was shown that, compared to a standard learning instruction, enacting did not enhance the clustering of episodic and taxonomic lists, but it did enhance memory performance. Furthermore, the enacting effect was strongest with an unrelated list; in all lists, organization and recall correlated only under a verbal instruction and not under an enacting instruction. In the second experiment, subjects were also informed about the categories of the lists and instructed to use them to learn the items. The organization was enhanced in all cases by this procedure, but the recall performance was enhanced only with a standard learning instruction. Under enacting, information about the categories had no influence. In the third experiment this effect was replicated for a taxonomic list and could be generalized for a motor list, in which categories were in accordance with the similarities of the movement pattern. Here too the explicit category information had an effect only under a standard learning instruction, but not with enacting. We interpret these effects as support for the assumption that enacting does not enhance memory performance by better relational information. Relational information is, on the contrary, less important for recall under enacting than under a standard learning instruction.     

Verbal cues facilitate memory retrieval during infancy

In three experiments, 18-month-olds were tested in a deferred imitation paradigm. Some infants received verbal information during the demonstration and at the time of the test (full narration), and some did not (empty narration). When tested after a 4-week delay, infants given full narration exhibited superior retention relative to infants given empty narration (Experiment 1). This retention advantage appears to be due to the effects of verbal cues at the time of memory retrieval. There was no effect of verbal cues that were presented only at the time of original encoding (Experiment 2A). Furthermore, infants who received verbal cues only at the time of retrieval exhibited superior retention relative to infants who received verbal cues only at the time of original encoding (Experiment 2B). These findings demonstrate that verbal cues can enhance memory retrieval by participants who are not yet fluent speakers themselves.     

The interval for interference in conscious visual imagery

Three experiments are described that use dynamic visual noise (DVN) to interfere with words processed under visual and verbal processing instructions. In Experiment 1 DVN is presented to coincide with the encoding of the words or to coincide with the interval between encoding and recall. The results show that while DVN is a robust disruptor when it is applied during encoding to words processed under visual instruction, it has no effect during encoding when the words are processed under rote instruction. Moreover, DVN has no effect when it is applied during the retention interval, no matter what means are employed to encode the words. Experiment 2 extends these findings by again showing no effect of DVN during the retention interval, yet showing robust interference effects for visually processed words during recall. Finally, Experiment 3 demonstrates that the results of Experiments 1 and 2 cannot be explained by a difference in the time duration associated with application of DVN during the retention interval compared to during encoding and recall. Moreover, the differing decay functions for visually and verbally processed words during the intervals used in Experiment 3 suggest that any failure to cause interference is not because the two processing instructions resulted in words being retained in the same medium. The functions are consistent with word storage mechanisms reflecting appropriately verbal and visual properties. The results are discussed in terms of current models of visual working memory. It is argued that a full interpretation of the results requires a buffer mechanism as an important component of any model of visual working memory.     

The interval for interference in conscious visual imagery

Three experiments are described that use dynamic visual noise (DVN) to interfere with words processed under visual and verbal processing instructions. In Experiment 1 DVN is presented to coincide with the encoding of the words or to coincide with the interval between encoding and recall. The results show that while DVN is a robust disruptor when it is applied during encoding to words processed under visual instruction, it has no effect during encoding when the words are processed under rote instruction. Moreover, DVN has no effect when it is applied during the retention interval, no matter what means are employed to encode the words. Experiment 2 extends these findings by again showing no effect of DVN during the retention interval, yet showing robust interference effects for visually processed words during recall. Finally, Experiment 3 demonstrates that the results of Experiments 1 and 2 cannot be explained by a difference in the time duration associated with application of DVN during the retention interval compared to during encoding and recall. Moreover, the differing decay functions for visually and verbally processed words during the intervals used in Experiment 3 suggest that any failure to cause interference is not because the two processing instructions resulted in words being retained in the same medium. The functions are consistent with word storage mechanisms reflecting appropriately verbal and visual properties. The results are discussed in terms of current models of visual working memory. It is argued that a full interpretation of the results requires a buffer mechanism as an important component of any model of visual working memory.     

Encoding information for future action: Memory for to-be-performed tasks versus memory for to-be-recalled tasks

What is the nature of the representation underlying memory for future tasks such as calling the doctor or buying milk? If this representation consists of a verbal instruction that is translated into action at the time of retrieval, then memory should be better when tested via verbatim recall of the instruction than when tested via actual performance. Three experiments rejected this possibility, indicating better memory for a perform mode of report than for a recall mode of report. This was true in Experiment 1 in which subjects saw a series of verbal instructions (e.g., “move the eraser,” “lift the cup,” “touch the ashtray”), with advance information regarding the mode of report required during testing. In Experiment 2, the advance cue was valid only in 75% of the trials. Memory depended more heavily on the expected mode of report thanon the actual mode ofreport, suggesting that the perform superiority is due to processes that occur during encoding. In Experiment 3, subjects learned 20 phrases depicting minitasks were remembered by subjects tested via performance than by subjects tested via verbatim recall. A second part of Experiment 3 also indicated superior memory when a perform test was expected, regardless of which mode of report was actually required. The results were compared with the finding that subject-performed tasks are better remembered thanare their verbal instructions, which suggeststhat the representation underlying memory for future assignments-may-take advantage of the imaginal-enactive properties ofthe envisagedacts. Other possible differences between memory for to-be-recalled tasks and memory for to-be-performed tasks are discussed.     

Implementation intentions facilitate prospective memory under high attention demands

An implementation intention is a planning technique that involves specifying a situation for initiating an intended action and linking these specific cues to the intention. In two experiments with young adults, we found significant increases in prospective memory with implementation intentions. With an implementation intention, but not with standard instructions, prospective memory performance was maintained under demanding attentional conditions (Experiment 2). Ongoing task performance did not decline, however, in relation with a no prospective memory control. Positive effects were not observed when the imagery component of the implementation intention was isolated from the verbal component. We suggest that implementation intention planning (relative to standard instructions) increases the likelihood that people will encode a robust associative link between the target cue and the intended action, thereby promoting reflexive triggering of the intended action on presentation of the target cue.     

The emergence of strategic knowledge activation in categorical clustering during retrieval

Elementary school children's free recall clustering has recently been explained as an automatic by-product of their developing knowledge base. In contrast, it is claimed that as children get older they become aware of the usefulness of category organization as a memory strategy that enables them to strategically activate category knowledge even during retrieval. To test this hypothesis an experimental procedure was developed where Ss first had to learn items in a noncategorical order to the criterion of two perfect serial recall trials. After a 12- to 15-min retention interval Ss unexpectedly received either serial or free recall (or--in Experiment 1--cued recall) instructions. In three experiments with second and fourth graders it was shown that (1) fourth graders' recall exceeded that of second graders only in the free, but not in the serial (or cued), recall condition, (2) higher levels of clustering were observed for fourth graders in the free recall condition, and (3) the grade effect on free recall data was eliminated when the influence of metamemory and categorical clustering statistically was partialled out (Experiments 1 and 3). This pattern of results proved robust against variants in which a metamemory question was asked or omitted prior to recall (Experiment 2) and manipulations in which age differences in categorical knowledge were minimized (Experiment 3). The results were interpreted as demonstrating fourth graders' strategic competence in activating category knowledge during retrieval and second graders' automatic knowledge activation.     

Task-relevant perceptual features can define categories in visual memory too

Although Konkle, Brady, Alvarez, and Oliva (2010, Journal of Experimental Psychology: General, 139(3), 558) claim that visual long-term memory (VLTM) is organized on underlying conceptual, not perceptual, information, visual memory results from visual search tasks are not well explained by this theory. We hypothesized that when viewing an object, any task-relevant visual information is critical to the organizational structure of VLTM. In two experiments, we examined the organization of VLTM by measuring the amount of retroactive interference created by objects possessing different combinations of task-relevant features. Based on task instructions, only the conceptual category was task relevant or both the conceptual category and a perceptual object feature were task relevant. Findings indicated that when made task relevant, perceptual object feature information, along with conceptual category information, could affect memory organization for objects in VLTM. However, when perceptual object feature information was task irrelevant, it did not contribute to memory organization; instead, memory defaulted to being organized around conceptual category information. These findings support the theory that a task-defined organizational structure is created in VLTM based on the relevance of particular object features and information.     

Individual differences in visuospatial working memory: benefits from environmental support for rehearsal

ABSTRACT

Previous research has suggested that participants with low working memory spans are less likely than those with high spans to engage in rehearsal and other effective strategies during memory tasks. However, most of this research has been conducted in the verbal domain, and less is known about strategy differences in visuospatial working memory. Therefore, the present experiments investigated potential individual differences in the benefit participants receive from environmental support for visuospatial rehearsal. In Experiment 1, memory spans were significantly larger when support was present (i.e. when the array of possible locations remained on the screen) during long inter-item intervals, but importantly, the observed benefit was larger for high-span participants than low-span participants, suggesting that high spans were more likely to use support to facilitate their rehearsal. Other research has suggested that low spans may benefit more than high spans from rehearsal instructions, and so in Experiment 2, participants also were provided with such instructions. However, the rehearsal instructions did not improve memory spans significantly in either group, suggesting that low spans are not only naturally less strategic than high spans, but they may be less capable of taking advantage of effective rehearsal strategies, even when environmental support is present.     

Source memory enhancement for emotional words

The influence of emotional stimuli on source memory was investigated by using emotionally valenced words. The words were colored blue or yellow (Experiment 1) or surrounded by a blue or yellow frame (Experiment 2). Participants were asked to associate the words with the colors. In both experiments, emotionally valenced words elicited enhanced free recall compared with nonvalenced words; however, recognition memory was not affected. Source memory for the associated color was also enhanced for emotional words, suggesting that even memory for contextual information is benefited by emotional stimuli. This effect was not due to the ease of semantic clustering of emotional words because semantically related words were not associated with enhanced source memory, despite enhanced recall (Experiment 3). It is suggested that enhancement resulted from facilitated arousal or attention, which may act to increase organization processes important for source memory.     

Asymmetric interference between domains: evidence from the stimulus order effect in complex span tasks

The stimulus order effect refers to the finding that recall in complex span tasks is better when span lists begin with a longer processing task and end with a shorter task than when these processing tasks are presented in the reverse order. This study independently manipulated processing time and processing difficulty between Long-final and Short-final lists. The processing task required participants to solve arithmetic problems with either verbal (Experiment 1) or visuospatial (Experiment 2) materials. The memory items used in the storage task were either digits (verbal material) or dots-in-matrices (visuospatial materials). Storage of both verbal and visuospatial materials was sensitive to the change in processing difficulty, but not processing time. Furthermore, this study provides further evidence for the asymmetry of domain interference in working memory. The similarities and differences between verbal and visuospatial storage in working memory are discussed.