Dissociating word stem completion and cued recall as a function of divided attention at retrieval

The aim of this study was to investigate the widely held, but largely untested, view that implicit memory (repetition priming) reflects an automatic form of retrieval. Specifically, in Experiment 1 we explored whether a secondary task (syllable monitoring), performed during retrieval, would disrupt performance on explicit (cued recall) and implicit (stem completion) memory tasks equally. Surprisingly, despite substantial memory and secondary costs to cued recall when performed with a syllable-monitoring task, the same manipulation had no effect on stem completion priming or on secondary task performance. In Experiment 2 we demonstrated that even when using a particularly demanding version of the stem completion task that incurred secondary task costs, the corresponding disruption to implicit memory performance was minimal. Collectively, the results are consistent with the view that implicit memory retrieval requires little or no processing capacity and is not seemingly susceptible to the effects of dividing attention at retrieval.     

Dissociating word stem completion and cued recall as a function of divided attention at retrieval

The aim of this study was to investigate the widely held, but largely untested, view that implicit memory (repetition priming) reflects an automatic form of retrieval. Specifically, in Experiment 1 we explored whether a secondary task (syllable monitoring), performed during retrieval, would disrupt performance on explicit (cued recall) and implicit (stem completion) memory tasks equally. Surprisingly, despite substantial memory and secondary costs to cued recall when performed with a syllable-monitoring task, the same manipulation had no effect on stem completion priming or on secondary task performance. In Experiment 2 we demonstrated that even when using a particularly demanding version of the stem completion task that incurred secondary task costs, the corresponding disruption to implicit memory performance was minimal. Collectively, the results are consistent with the view that implicit memory retrieval requires little or no processing capacity and is not seemingly susceptible to the effects of dividing attention at retrieval.     

Facilitation of recall with intralist cues: Time-dependent characteristics of cued recall

List items were given as retrieval cues in a free-recall experiment which factorially combined the presence or absence of cues with the amount of time allowed for use of each cue (10 sec or 30 sec). A categorizable list of 75 randomly presented words was learned, and 48 h later a free-recall test trial was given, followed by a final memory search task. During the final task, cued subjects received words from categories that had not been recalled during the free-recall test. With both time intervals, cued subjects recalled more words than noncued subjects, indicating that random presentation of categorized words does not necessarily preclude the observation of a cueing effect with list items, as has been reported previously. The composition of recall, whether from previously recalled or nonrecalled categories, varied as a function of time for both groups. The results were interpreteod in terms of retrieval strategies employed by cued and noncued subjects and the effect of time on these strategies.     

Lexical and semantic search in cued recall, fragment completion, perceptual identification, and recognition

Search processes in word-stem cued recall, fragment completion, perceptual identification, and recognition are contrasted. These retention tests involve letters as cues, but the lexical characteristics of these cues vary considerably. In word-stem cued recall, ending letters are presented as recall cues for studied targets (e.g., ONEY as a cue for HONEY). In fragment completion, the test cues consist of letters and spaces (e.g., HO__Y); in perceptual identification, they consist of letter features that survive the mask; and in recognition, they consist of all the letters of the studied word (e.g., HONEY). These differences in retention tests and lexical characteristics were evaluated by manipulating three variables with known effects in cued recall: (a) the presence of study context words emphasizing lexical information, (b) lexical set size corresponding to the number of words that fit the letter cue, and (c) meaning set size corresponding to the number of meaningful associates linked to the studied targets. The results indicated that (a) the presence of study contexts emphasizing lexical information reduced accuracy and response time equally in all tasks, (b) larger lexical set sizes reduced accuracy and response time in all tasks except recognition, and (c) larger meaning set size reduced accuracy in cued recall but not in the other tasks. Lexical search appears to be a significant component process in word-stem cued recall, fragment completion, and identification. Searching through meaning-related concepts encoded during study is a significant component process only in cued recall.     

Determinants of word fragment completion

A current debate in the memory literature concerns the validity of word fragment completion (WFC) as a test of implicit memory. It has been claimed that language variables exert a strong influence on the task, and that the task reflects memory only to a small extent (Hintzman & Hartry, 1990). For these reasons, the use of contingency analyses of recognition and WFC performance as a means of studying underlying memory processes has been criticized. The present study addressed this issue by examining the influence of language variables on completion of a set of computer generated single-solution fragments of Swedish words (Olofsson & Nyberg, 1992). It was found that language variables indeed had a large effect on completion performance, and that priming only accounted for a small portion of variance in the task. It is therefore suggested that the method of triangulation should be employed for contingency analyses involving WFC.     

Word stems as cues in recall and completion tasks

Subjects tend to complete word stems to form words to which they have recently been exposed. These priming effects in word-stem completion are compared to cued recall, where subjects are asked to recall list items and are given word stems as cues. Intentionality of learning and duration of rehearsal affected recall performance but not the magnitude of priming in word-stem completion. However, cued recall and word-stem tasks did not exhibit stochastic independence: performance on one task was strongly related to performance on the other. These results are inconsistent with extreme accounts that would attribute performance on these tasks either to entirely separate systems or to an identical set of processes.     

Hypermnesia in free recall and cued recall

In three experiments, categorized lists and both free recall and cued recall tests were used to examine hypermnesia. In Experiment 1, materials were drawn from obvious and nonobvious categories in an attempt to vary the amount of relational processing at encoding. The study materials in Experiment 2 consisted of a long word list that comprised several exemplars from each of a number of common categories. In Experiment 3, a single exemplar was drawn from each of 45 categories. In each experiment, similar magnitudes of hypermnesia were obtained on free and cued recall tests. Examination of the specific items recalled across tests indicated that similar processes underlie the hypermnesic effect for both test conditions. Implications of the results for extant accounts of the hypermnesic effect are discussed. It is concluded that the dynamics of retrieval processes change in a systematic fashion across repeated tests and the retention interval following study and that an adequate account of the nature of these changes in retrieval dynamics is essential to our understanding of hypermnesia and related phenomena.     

Selective access in cued recall: The roles of retrieval cues and domains of encoding

The purpose of these experiments was to determine whether retrieval access in cued recall can be selectively restricted to a single domain of encoding when information has been encoded within two domains as different as word sound and word meaning. In Experiment 1, the subjects studied pairs of rhyming words differing in rhyme set size under verbal-repetition or interactive-imagery instructions. Recall was cued with study-context rhymes, with extralist rhymes, or with extralist associates. The results indicated that rhyme set size and instructional effects were found no matter how recall was cued, indicating that both domains of encoding were always accessed. In Experiment 2, potential effects of study time and overt naming of the test cues were explored. These results indicated that both domains of encoding were accessed, except when long study times were available and subjects did not have to name the rhyme test cues. Rhyme set-size effects were eliminated under these conditions, suggesting that selective access to encoded meaning is possible in cued recall. Retrieval access in this task appears to be more controlled by domains of encoding than by information directly available in the cue, and access to encoded information can be restricted to a single domain.     

Bias effects in word fragment completion in young and older adults

Young and older adults were tested on a word fragment completion task in which correct solutions were studied words, words orthographically similar to studied words, or new words. In Experiments 1 and 2, the standard production version of the word fragment completion task was used; older adults had reduced benefits of prior exposure to target words and slightly decreased costs. However, costs and benefits did not differ across age in a forced-choice version of the task (Experiment 3). At a behavioral level, the results are contrary to predictions that age differences in word fragment completion priming effects will be greater when there is a strong competitor for the correct solution and that age differences in both costs and benefits will be smaller for identification than for production tasks. Theoretical implications of these findings are considered.     

Direct comparison of two implicit memory tests: word fragment and word stem completion.

In 3 experiments, the implicit memory tests of word fragment and word stem completion showed comparable effects over several variables: Study of words produced more priming than did study of pictures, no levels-of-processing effect occurred for words, more priming was obtained from pictures when Ss imaged the pictures' names than when they rated them for pleasantness, and forgetting rates were generally similar for the tests. A different pattern of results for the first 3 variables occurred under explicit test conditions with the same word fragments or word stems as cues. We conclude that the 2 implicit tests are measuring a similar form of perceptual memory. Furthermore, we argue that both tests are truly implicit because they meet Schacter, Bowers, & Booker's (1989) retrieval intentionality criterion: Levels of processing of words have a powerful effect on explicit versions of the tests but no effect on implicit versions.     

Perceptual identification, fragment completion, and free recall: concepts and data

The effects of orthographically distinctive and orthographically common words were compared on tests of free recall, fragment completion, perceptual identification, and lexical decision. Orthographic distinctiveness is argued to effect data-driven processing and, in light of recent theory, should have little effect upon free recall but substantial effects upon fragment completion and perceptual identification. The results showed superior recall and fragment completion of orthographically distinctive words but more accurate perceptual identification of orthographically common words. Latency of lexical decision was longer for orthographically distinctive than for orthographically common words. The visual complexity of orthographically distinctive words may require more extensive sensory processing than is possible within the temporal constraints of perceptual identification tests. The effect of orthographic distinctiveness upon free recall reveals a certain inadequacy in the notion of transfer-appropriate processing.     

Retrieval processes in recognition and cued recall

The present studies used response time (RT) and accuracy to explore the processes and relation of recognition and cued recall. The studies used free-response and signal-to-respond techniques and varied list length and presentation rate. In Experiment 1, the free-RT distributions for recognition had much lower mean and variance than those for cued recall. Similarly, signal-to-respond curves showed fast rates of accumulation of information in recognition and slow rates in recall. (Quantitative models of the results are presented in the companion article by D. E. Diller, P. A. Nobel, and R. M. Shiffrin, 2001). To rule out the possibility that the slower responses in cued recall were due to a fast retrieval process followed by a slow process of cleaning up the retrieved trace for output, additional signal-to-respond tasks provided the relevant alternatives at test. Yet, these conditions showed slow growth rates, similar to those seen in recall. The results support the hypothesis that retrieval processes differ for single-item recognition and cued recall, with retrieval in cued recall (and associative recognition) due to a sequential search.     

Affective valence and memory in depression: dissociation of recall and fragment completion.

Depressed (n = 16) and nondepressed (n = 16) subjects' memory for affectively valenced words was assessed by an explicit test (free recall) and an implicit test (word fragment completion). Under free-recall instructions, depressed subjects recalled significantly more negatively valenced than positively valenced words, whereas the opposite pattern was observed in nondepressed control subjects. These results replicate those previously reported in the literature. The differential effect of word valence was absent, however, when memory was tested implicitly: Depressed and nondepressed subjects exhibited equivalent priming of positive and negative words. These data are discussed in terms of Williams, Watts, MacLeod, and Mathews's (1988) model of depression.     

Retrieval operations in cued recall and recognition

The present study compared the effects of two classes of experimental manipulations on the recognition and cued recall of target words learned in the presence of list cues. One class of manipulations, learning instructions (repetition vs. meaningful rehearsal), had similar effects on recall and recognition, whereas the other, preexperimental association between target and cue words, had separable effects: Cue-to-target association affected only recall, while target-to-cue association affected only recognition performance. Recall and recognition were thus viewed as fundamentally similar processes, both of which require retrieval operations. Differences between the two were attributed to the differential abilities of the recall and recognition retrieval cues to access the original episodic event.     

The role of syllabic and orthographic properties of letter cues in solving word fragments

The present research examined the role of phonological and orthographic properties of cues in mediating the retrieval of words from the mental lexicon. The task required subjects to resolve fragmented words when provided with semantically related cues (e.g., spiteful:---DIC----). Phonological properties of the letter cues were manipulated such that the letters either corresponded to the syllables (e.g., DIC in vindictive) or nonsyllables (NDI) in the word. Orthographic properties of the letter cues were manipulated by selecting letter groups that either co-occurred frequently in the language or did not. In two experiments, results revealed little or no effect of the phonological variable (syllables) but a reliable effect of the orthographic variable (letter-cue frequency). Letter cues with a low frequency of co-occurrence in the language led to better completion of the fragmented words. We interpret these findings as support for models of lexical representation that are based on orthographic properties (e.g., Seidenberg & McClelland, 1989) rather than those based on phonological constraints.     

Memory for previous recall: a comparison of free and cued recall

Case studies of individuals who claimed to have recovered previously repressed memories of abuse during situations that involved memory cueing revealed that some individuals had discussed abuse with others during an earlier time period. Termed the ‘forgot‐it‐all‐along’ effect, this phenomenon has legal implications for statutes of limitations. Two experiments provide evidence for differences between free recall and more directed (recognition or cued recall) test conditions in the accuracy of memories for previous recall. Participants more often erred by claiming they had not previously remembered recognized (Experiment 1) or cued (Experiment 2) sentences than freely recalled sentences, and this difference was obtained even when the number of remembered sentences was equivalent across conditions (Experiment 2). These studies document that memory for previous recollection is less accurate for cued memories even when remembered events do not produce feelings of shock or surprise. Copyright © 2002 John Wiley & Sons, Ltd.     

Encoding specificity and unidirectional associates in cued recall

The first of two experiments confirmed the earlier findings of Humphreys and Galbraith (1975), that under silent-study encoding instructions, words assessed as strong elicitors of target words are effective extralist retrieval cues, whereas words assessed as weak elicitors are not. In the second experiment, predictions from the encoding specificity principle were confirmed with respect to the effectiveness of forward and backward retrieval cues in recall. Contrary to the conclusions of Humphreys and Galbraith, forward and backward unidirectional associates were equally effective as retrieval cues, provided subjects engaged in associative encoding (generated associations to the target words) at storage.     

Influences of item organizability and semantic retrieval cues on word recall in very old age

Abstract

This research investigated the influence of organizational structure in the materials and category cues at retrieval on episodic memory performance in very old age. A community-based sample of healthy, very old adults (N = 224) between 75 and 96 years was presented with two lists of words: a list of semantically unrelated words and a list of words from four taxonomic categories randomly intermixed. Free recall was assessed for both tasks and, for the organizable list, subjects received a cued recall test as well. Results showed an overall age-related deterioration of memory performance, although the ability to utilize item organizability and retrieval cues remained intact across age. Evidence from data on memory performance, as well as analyses of the nature of organizable free recall, suggests that problems at both encoding and retrieval may underlie the age-related performance deficit. In addition, there were age-related increases in (a) forgetting between free and cued recall, and (b) intrusion errors. Finally, regression analyses indicated that, in addition to age, level of schooling as well as markers of general cognitive status (the Mini-Mental State Examination) and fluid intelligence (Block Design) accounted for performance variation across all memory tasks.     

Repetition effects on word fragment completion: The role of competition among responses

Four experiments examined the effect of spaced repetition of study words on completion of word fragments with only one solution and word fragments with multiple solutions. Recognition was used as test of explicit memory in the first two experiments. The study words were presented either once or three times. Repetition was found to increase recognition memory substantially, and to affect fragment completion performance only marginally. This was true for both single- and multiple-solution fragments, showing that competition among responses is not critical for the magnitude of the repetition effect in fragment completion. This finding, that the repetition effect is marginal also when the type of cues provides an occasion for repetition effects to show up, suggests that the real effect of repetition on perceptual priming is borderline. It is proposed that memory from the first presentation eliminates necessary processing of items when they are re-exposed, and that the repetition effect thereby is reduced.