Separate effects of word frequency and age of acquisition in recognition and recall.

Three experiments investigated word frequency and age of acquisition (AoA) effects in recognition and recall. Experiments 1 and 2 used the "remember-know" procedure developed by J. M. Gardiner (1988). In Experiment 1, recognition performance was higher for low-frequency words than for high-frequency words and higher for late-acquired words than for early-acquired words, but only in "remember" responses. Experiment 2 replicated the AoA effect by using a different set of early- and late-acquired words. Experiment 3 found advantages for low-frequency and late-acquired words in recall, but only when words were presented in mixed lists. The frequency effect was reversed, and the AoA effect was eliminated, when participants studied pure lists. Findings were attributed to the more distinctive encoding of low-frequency and late-acquired words. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Dissociative effect of massed repetition on implicit and explicit measures of memory.

Ss saw or heard words presented once, or repeated 4 or 16 times in massed fashion, and then received an implicit or explicit memory test. Massed repetition did not increase priming on word fragment completion beyond that obtained from a single presentation but did enhance performance on various explicit tests (free recall, recognition, question cued recall, and word fragment cued recall) and an implicit general knowledge test. Modality of presentation affected implicit and explicit word fragment cued tests but did not affect performance on any of the other tests. Levels of processing affected performance on implicit and explicit question cued tests. These results are consistent with a transfer appropriate processing account of dissociations among memory measures and imply that massed repetition promotes conceptual processing but does not entail a repetition of perceptual-based processes responsible for priming on word fragment completion. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Limiting lexical activation limits perceptual priming in masked word identification

Four experiments tested the hypothesis that perceptual priming of a word depends on the prior lexical processing of the word (Rajaram & Roediger, 1993; Weldon, 1991). Experiment 1 showed that first-letter naming reduced priming relative to reading a whole word on two tests: word fragment completion and masked word identification. In Experiment 2, naming the first letter of a word took longer than naming the letter presented alone, and led to better masked word identification. Experiment 3 showed that masked word identification was enhanced by prior word processing more for low frequency words than for high frequency words, but only when words had been read aloud. Experiment 4 tested whether the auditory input accruing from reading a word aloud was the source of facilitation and frequency effects. Participants judged either the frequency of the whole display or the positional frequency of the first letter in the display, and indicated their decisions manually. The major findings from Experiment 3 were replicated, ruling out the cross-modal source of those effects. It was concluded that activation of a lexical unit, one component of word processing (Vriezen, Moscovitch, & Bellos, 1995), is a critical determinant of the perceptual priming of that word.     

Short-term implicit memory for words and nonwords.

A short-term implicit memory effect is reported and interpreted as arising within the word recognition system. In Experiment 1, repetition priming in lexical decision was determined for low-frequency words and pseudowords at lags of 0, 1, 2, 3, 4, 5, 9, and 23 intervening items. For words, a large short-term priming component decayed rapidly but smoothly over the first 3 items (8 s) to a stable long-term value. For nonwords, priming dropped to the long-term value with a single intervening item. This Lag x Lexicality interaction was replicated with a naming task in Experiment 2 and with high-frequency words in Experiment 3. Word frequency affected long-term priming but not the size or decay rate of short-term priming, dissociating the two repetition effects. In Experiment 4, an old-new decision task was used to test explicit memory. Parallel word and nonword decay patterns were found, dissociating short-term priming from explicit working memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Direct comparison of four implicit memory tests.

Four verbal implicit memory tests, word identification, word stem completion, word fragment completion, and anagram solution, were directly compared in 1 experiment and were contrasted with free recall. On all implicit tests, priming was greatest from prior visual presentation of words, less (but significant) from auditory presentation, and least from pictorial presentations. Typefont did not affect priming. In free recall, pictures were recalled better than words. The 4 implicit tests all largely index perceptual (lexical) operations in recognizing words, or visual word form representations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Word context during initial exposure influences degree of priming in word fragment completion.

Priming in word fragment completion is revealed by the increased probability of correctly completing a fragment like "_ll_p_e' when the word "ellipse' was seen recently. Three experiments investigated the effects on priming of manipulating the context in which the words were seen. Three principal results emerged. Experiments 1 and 2 demonstrated that there was much more priming for words studied in a to-be-learned list than read in meaningful passages. In these same two experiments, low-frequency words were subject to more priming than were higher frequency words, regardless of context. Experiment 3 revealed more priming for words when they did not fit sensibly into connected discourse than when they did. The results suggest that context plays a critical role in priming: As a word moves from being contextually bound in meaningful discourse to being isolated in a list, its probability of priming increases. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of dividing attention on the memory-block effect.

S. M. Smith and D. R. Tindell (1997) reported that prior study of words that are orthographically similar to the solutions of test word fragments (e.g., studying ANALOGY and completing the fragment A L_ _GY, whose solution is ALLERGY) reduced the fragment completion rate relative to a baseline condition in which unrelated words were studied. They called this effect the memory-block effect. In the present experiment, the authors replicated this effect using a larger set of materials than that used by S. M. Smith and D. R. Tindell. The authors also found that dividing attention at study eliminated the memory-block effect. This pattern mimicked the effect of dividing attention on recognition memory but differed from the effect on repetition priming effects. The authors suggest that the memory-block effect is driven by a mechanism different from that responsible for producing repetition priming effects in an implicit fragment completion test. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of imagery on perceptual implicit memory tests.

Four experiments demonstrate that imagery can promote priming on perceptual implicit memory tests. When Ss were given words during a study phase and asked to form mental images of corresponding pictures, more priming was obtained on a picture fragment identification test than from a study condition in which Ss performed semantic analyses of words. Imaginal priming of picture fragment identification occurred for recoverable fragments, but not for nonrecoverable fragments. The imagery effect was restricted to the imaged type of material: Imagining pictures (when presented with words) enhanced priming on a picture fragment identification test but not on word fragment completion. Similarly, when pictures were presented, imagining the corresponding words increased priming on word fragment completion but not on picture fragment identification. Overall, results support the hypothesis that imagining engages some of the same mechanisms used in perception and thereby produces priming. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

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. It is concluded that the 2 implicit tests are measuring a similar form of perceptual memory. Furthermore, it is argued that both tests are truly implicit because they meet the D. L. Schacter et al (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. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Detection of Kanji words in a rapid serial visual presentation task.

In 3 experiments, lists of 12 Kanji words were rapidly presented in the same position, and participants reported a red target word embedded in green distractor words. Two lists were used: same and different category. A tendency toward category priming was found at longer durations. Frequency of target localization indicated that participants familiar with Kanji had a greater tendency to report the word immediately preceding the target. These pretarget intrusion errors dominated the posttarget intrusion errors, when the luminance of red and green stimuli were equated (Experiment 2), and when the response was recall (Experiments 1 and 2) or recognition (Experiment 3). In contrast, participants unfamiliar with Kanji made posttarget intrusion errors as frequently as pretarget intrusion errors (Experiment 3), suggesting that knowledge of Kanji influences the integration of color and form codes in visual information processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Conceptual priming in fragment completion.

Some researchers have claimed that fragment completion tasks are dependent primarily on data-driven processing and are insensitive to conceptually driven processing. In this article we present four experiments demonstrating that conceptually driven processing affects fragment completion by showing that under appropriate conditions, studied words can facilitate identification of their picture and word fragments. We examine two theoretical explanations of this effect. First, we consider the possibility that subjects explicitly retrieve episodic representations in fragment completion. Analyses of correlations between priming and recall performance across items and subjects do not support this explanation. The alternative explanation is that there are two separate conceptual representations in memory. The first is assumed to mediate conceptual priming in fragment completion; the second is assumed to mediate free recall performance. A final experiment supports this view by demonstrating that even when differences between experimental conditions are made to disappear in fragment completion, they remain in free recall. Further applications of the notion of two semantic representations are discussed in the General Discussion. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Associative priming in word fragment completion: a dissociation between explicit and implicit retrieval processes

Three experiments investigated associative priming in word fragment completion. In associative priming, the study word that acts as a prime is semantically related in some way to the response word that the subject must produce or respond to at test. For example, a prime might be semantically related to the solution to its paired word fragment (e.g. study "VANILLA", solve fragment "-H-C--A-E" at test, solution is "CHOCOLATE"). Associative priming therefore differs from both repetition and conceptual priming, in which the studied primes are themselves the words that must be produced or responded to at test. In Experiment 1, associative primes were found to influence word fragment completion performance on an explicit test, but not on an implicit test. Experiment 2 demonstrated that the effects of associative primes on explicitly instructed fragment completion cannot be attributed to the specific information about cue-prime relationships that is included in the explicit instructions. Experiment 3 demonstrated that a manipulation of modality, a variable known to disrupt implicit retrieval processes, disrupts repetition priming on an explicit test, but not associative priming. The results of these three experiments suggest that whereas repetition primes are retrieved from memory by both explicit and implicit retrieval processes, associative primes are retrieved by only explicit processes. These data suggest that implicit retrieval processes are cue-dependent processes which automatically retrieve memory information that provides a good match to retrieval cues. Explicit retrieval processes are cue-independent, functioning as an intentional retrieval set to access particular categories or types of memory information.     

Forgetting in primed fragment completion.

Seven experiments examined the time course of primed fragment-completion performance. A pilot experiment and Experiment 1 showed that rapid forgetting occurs immediately after study for a period of approximately 5 min. The rate of this immediate forgetting is independent of the length of the list. Experiment 2 showed that priming effects were still present after 16 months. Experiments 3 and 4 provided further evidence of forgetting over 1 week. Experiment 5 showed that retention performance after 20 min is unaffected by the interpolated study and recall of other lists of words. Experiment 6 showed that 10-min retention performance was substantially reduced as list length was increased from 10 to 100 words; but it showed no evidence of intralist proactive interference. The combined results of the seven experiments illustrate some similarities and differences between forgetting in primed fragment completion and in episodic memory tasks such as recall and recognition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Rate of forgetting in amnesia: II. Recall and recognition of word lists at different levels of organization.

Amnesic rate of decline of free recall, cued recall, and recognition of word lists with different levels of organization was investigated in 2 experiments. In Experiment 1, it was found that amnesic free recall of semantically related word lists declined at an accelerated rate, whereas free recall of lists of unrelated words declined at a normal rate. Cued recall and recognition performance of both kinds of word lists appeared to decline at a normal rate. In Experiment 2, the results of the free-recall and recognition conditions were replicated using an improved experimental design. The observed amnesic forgetting pattern is interpreted as arising from an impairment in consolidation of long-term memory for complex associations between 2 or more items and their study context that is caused by extended hippocampal system lesions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The role of attention during encoding in implicit and explicit memory.

In 5 experiments, participants read study words under conditions of divided or full attention. Dividing attention reduced performance on the general knowledge test, a conceptual implicit test of memory. Likewise, dividing attention reduced conceptual priming on the word association task, as well as on a matched explicit test, associate-cued recall. In contrast, even very strong division of attention did not reduce perceptual priming on word-fragment completion, although it did reduce recall on the matched explicit test of word-fragment-cued recall. Finally, dividing attention reduced recall on the perceptual explicit tests of graphemic-cued recall and graphemic recognition. The results indicate that perceptual implicit tests rely minimally on attention-demanding encoding processes relative to other types of memory tests. The obtained pattern of dissociations is not readily accommodated by the transfer-appropriate-processing (TAP) account of implicit and explicit memory. Potential extensions of the TAP view are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Code-specific processes in word naming: Evidence supporting a dual-route model of word recognition.

This research examined visual and phonological coding in visual word recognition, Participants named words while performing 1 of 3 memory tasks. The difficulty of the memory tasks was varied. In Experiment 1, increasing the difficulty of a digit-memory load resulted in slower naming of low-frequency regular (e.g., wink) words but faster naming of low-frequency exception (e.g., pint) words. In Experiment 2, increasing the difficulty of a dot-memory load slowed naming of low-frequency exception words more than naming of low-frequency regular words. In Experiment 3, increasing the difficulty of a tone-memory load resulted in slower naming of both low-frequency regular and exception words. The results are consistent with dual-route assumptions concerning code-specific processes in word recognition. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Ribosomal RNA: a key to phylogeny

Subjects studied a list of words (e.g., cheetah) and received an implicit word fragment completion test (complete -h-t-h). On the test, the ratio of studied to nonstudied items (proportion overlap) was 0, 25, 50, 75, or 100%. Subjects were administered the identical test twice. Proportion overlap did not affect priming in word fragment completion, on either the first or second test. Also, the completion of studied and nonstudied fragments increased over repeated tests, but priming (the studied-nonstudied rate) remained unchanged. The proportion overlap of items between study and test does not affect performance on primed word fragment completion.     

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. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Lexical precision in skilled readers: Individual differences in masked neighbor priming.

Two experiments investigated the relationship between masked form priming and individual differences in reading and spelling proficiency among university students. Experiment 1 assessed neighbor priming for 4-letter word targets from high- and low-density neighborhoods in 97 university students. The overall results replicated previous evidence of facilitatory neighborhood priming only for low-neighborhood words. However, analyses including measures of reading and spelling proficiency as covariates revealed that better spellers showed inhibitory priming for high-neighborhood words, while poorer spellers showed facilitatory priming. Experiment 2, with 123 participants, replicated the finding of stronger inhibitory neighbor priming in better spellers using 5-letter words and distinguished facilitatory and inhibitory components of priming by comparing neighbor primes with ambiguous and unambiguous partial-word primes (e.g., crow#, cr#wd, crown CROWD). The results indicate that spelling ability is selectively associated with inhibitory effects of lexical competition. The implications for theories of visual word recognition and the lexical quality hypothesis of reading skill are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Word-fragment cuing: The lexical search hypothesis.

In four experiments we evaluated aspects of the hypothesis that word-fragment completion depends on the results of lexical but not semantic search. Experiment 1 showed that the number of meaningful associates linked to a studied word does not affect its recovery when the test cue consists of letters and spaces for missing letters. Experiments 2 and 3 showed retroactive interference effects in fragment completion when words in a second list were lexically related to words in a first list but not when the words in the second list were meaningfully related. Experiment 4 indicated that for studied words, instructions to search at the word level facilitated completion performance and that instructions to generate letters to fill missing spaces had no effect. Other findings indicate that completion was affected by the number of words lexically related to the fragment and by the number of letters missing from the fragment. In general, experimental manipulations that focused on lexical characteristics were effective, and those that focused on semantic characteristics were ineffective. The findings support the conclusion that word fragments engender a lexical search process that does not depend on retrieving encoded meaning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)