Orthography and phonology in lexical decision: Evidence from repetition effects at different lags.

Full- and partial- (orthographic or phonemic) repetition effects for Hebrew voweled and unvoweled words and nonwords were examined at Lags 0 and 15 between the first and the second presentations. For voweled words, phonemic and orthographic partial-repetition effects were equivalent at Lag 0, each about half the size of the full-repetition effect. At Lag 15, the full-repetition effect was reduced to the size of phonemic repetition, which was as big as it was at Lag 0. In contrast, the orthographic repetition effect disappeared. For unvoweled words, the phonemic repetition effect was significant only at Lag 0, whereas the full-repetition effect was significant at both lags. Lexical decisions for both voweled and unvoweled nonwords were facilitated only by full repetition at Lag 0. It was concluded that addition of vowel marks attracted the subjects' attention and, therefore, lexical decisions for voweled stimuli were mediated by phonemic analysis. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

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)     

Toward a unified account of spacing effects in explicit cued-memory tasks.

Memory for repeated items improves when presentations are spaced during study. This effect is found in memory tasks using different types of material, paradigms, and participant populations. Although several explanations have been proposed, none explains the presence of spacing effects in cued-memory tasks for unfamiliar stimuli. Two experiments assessed the spacing effect on a yes-no recognition-memory task using nonwords and words as targets. The main results showed that changing the font between repeated occurrences of targets at study removed the spacing effect for nonwords only. A 3rd experiment using lexical decision showed that the font manipulation reduced repetition priming of nonwords when items were repeated at Lag 0. These results suggest that short-term perceptual priming supports spacing effects in cued-memory tasks for unfamiliar stimuli. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Event-related potentials differentiate the effects of aging on word and nonword repetition in explicit and implicit memory tasks.

Explicit memory declines with age while implicit memory remains largely intact. These experiments extended behavioral findings by recording event-related potentials (ERPs) in young and elderly adults during repetition priming and recognition memory paradigms. Words and pronounceable nonwords repeated after 1 of 3 delays. Stimuli were categorized as either word-nonword or old-new. Repeated items elicited more positive-going potentials in both tasks. Hemispheric asymmetries for word and nonword processing were observed during lexical decision: Repetition effects were larger over the left hemisphere for words and over the right hemisphere for nonwords. For the young, ERP repetition effects were larger during recognition memory. For old adults, conversely, repetition produced more positive-going waveforms during lexical decision. The elderly had ERP and behavioral deficits at long recognition delays. ERP repetition effects in the elderly, like behavioral performance, were preserved in an implicit task but impaired in an explicit memory task. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Repetition priming of words and pseudowords in divided attention and in amnesia.

Repetition priming of novel stimuli (pseudowords) and stimuli with preexisting representations (words) was compared in 2 experiments. In one, 19 normal male Ss performed a lexical decision task with either focused or divided attention. In another, lexical decision performance was compared between 8 male Korsakoff patients and 8 alcoholic control Ss. In control conditions, repetition sped responses to both stimulus types. Experimental conditions that minimized the contribution of episodic memory to task performance eliminated reaction time (RT) priming for pseudowords but not for words. However, in these same conditions, repetition increased the likelihood that pseudowords would be incorrectly classified. These results indicate that preserved repetition priming effects in amnesia do not solely reflect activation of representations in semantic memory. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Nonword Repetition Priming in Lexical Decision Reverses as a Function of Study Task and Speed Stress.

The authors argue that nonword repetition priming in lexical decision is the net result of 2 opposing processes. First, repeating nonwords in the lexical decision task results in the storage of a memory trace containing the interpretation that the letter string is a nonword; retrieval of this trace leads to an increase in performance for repeated nonwords. Second, nonword repetition results in increased familiarity, making the nonword more "wordlike," leading to a decrease in performance. Consistent with this dual-process account, Experiment 1 showed a facilitatory effect for nonwords studied in a lexical decision task but an inhibitory effect for nonwords studied in a letter-height task. Experiment 2 showed inhibitory nonword repetition priming for participants tested under speed-stress instructions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The fate of repetition effects when recognition approaches chance.

Examined whether repetition priming effects remain above baseline when explicit recognition is reduced to chance or near chance levels by forgetting. Ss studied a set of words, and memory was tested explicitly by yes/no (Exps 1 and 3) or forced-choice recognition (Exp 3) after a 20-min delay filled with an interfering task. Memory was then tested implicitly by perceptual identification (Exp 3) or lexical decision (Exps 1 and 2) for words seen only at study, at recognition, or both. In all experiments, recognition d' was about 0.75, and repetition effects remained above baseline and constant across conditions. At delays of 24 hrs (Exp 4) yes/no recognition fell to near chance (d'?     

Strategical invariance in lexical access: The reappearance of the pseudohomophone effect.

Examined the relationship between the presence of homophones and the appearance of the pseudohomophone effect, using 26 undergraduates. Ss were exposed to 10 pseudohomonyms, 10 nonwords, and 20 homophonic words or 20 nonhomophonic words in the 1st trial and to 15 pseudohomophones, 15 nonwords, and 30 nonhomophonic words during the 2nd trial. Ss' reaction time (RT) to a lexical decision task was recorded. Ss exposed to homophonic words during the 1st trial showed greater RT for decisions on pseudohomophones (pseudohomophone effect). Results support the conclusion of I. Dennis et al (1985) that the presence of homophones encourages a strategy of lexical decision making that changes the use made of phonological evidence. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Recognition and lexical decision without detection: Unconscious perception?

Stimulus detection and concurrent measures of stimulus recognition were compared to establish whether perception occurs in the absence of detection. The target stimuli were familiar words (Experiments 1 and 2), nonwords (Experiment 3), or both words and nonwords (Experiment 4). On each trial, either a stimulus or a blank field was presented. Ss first decided whether a stimulus had been presented and then made either a forced-choice recognition decision (Experiments 1, 2, and 3) or a lexical decision (Experiment 4). Both words and nonwords were recognized and discriminated following correct decisions (i.e., hits). However, in the absence of stimulus detection (i.e., misses), only words were recognized or discriminated. These qualitatively different patterns of results following hits and misses for words and nonwords suggest that stimulus detection may provide an adequate measure of conscious awareness. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Word stem and word fragment completion following semantic activation and elaboration.

In 5 experiments, Ss made timed lexical decisions to target words (or nonwords) preceded by primes that were semantically related or unrelated to them. Subsequently, a stem or fragement completion task was administered as an implicit memory test (e.g., complete bu for butter), followed by an explicit recognition test of memory for the previously seen primes and targets. Conditions of presentation for the lexical decision task were varied across experiments. In Exp 1, both semantic relatedness and semantic elaboration (primes vs targets) influenced performance on both the implicit and explicit tests. In Exps 2–5, a dissociation was obtained between the tests, with reliable effects of relatedness and eleaboration obtained for recognition but not completion. The notion of presemantic representations (E. Tulving and D. L. Schacter [see PA, Vol 77:16343] and Schacter [see PA, Vol 80:368]) is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

An event-related potential examination of masked and unmasked repetition priming in Alzheimer's disease: Implications for theories of implicit memory.

Fifteen patients diagnosed with Alzheimer's disease (AD) and 26 matched older controls engaged in a lexical-decision task with a list of words and nonwords while event-related brain potentials (ERPs) were recorded. Two repetition conditions were embedded in the list: words repeated at relatively long lags or words repeated shortly after a brief masked presentation. Although older controls displayed behavioral and ERP repetition priming for words repeated at long lags, consistent with previous studies, AD patients displayed neither. In contrast, both controls and AD patients displayed an ERP repetition priming effect for words repeated shortly after a brief masked presentation. ERP priming effects for masked and unmasked repetition differed in older controls, and additionally, the ERP masked priming effect differed between controls and AD patients. Results are discussed in the context of studies that have examined memory performance in brain-damaged populations using an impaired-intact dichotomy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Are lexical decisions a good measure of lexical access? Repetition blocking suggests the affirmative.

Examined the suggestion by D. A. Balota and J. I. Chumbley (see record 1985-05804-001) that lexical decisions can be based on computed values of a frequency/meaningfulness (FM) dimension for words and nonwords. Two experiments with 200 university students manipulated repetition of words and nonwords. Word repetition had a facilitating effect on response latencies for both words and nonwords, but nonword repetition had little or no effect. Results support a deadline decision model in which lexical decisions are based on lexical entries being activated beyond some criterion threshold within a prescribed period of time. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Evidence of flexible coding in visual word recognition.

In 3 visual word recognition experiments, the authors examined Ss' differential dependence on phonological vs orthographic information in accessing the lexicon. The critical manipulation was the presence or absence of pseudohomophones in the nonword context of a lexical decision task. Ss received a list with either no pseudohomophones (NPsH group) or 17–30% pseudohomophones among the nonwords (PsH group). In the 1st 2 experiments Ss in the PsH group were faster and no less accurate on word trials than Ss in the NPsH group. Furthermore, performance in the NPsH group was adversely affected by phonological inconsistency in the target's orthographic neighborhood. In the final experiment, a double lexical decision paradigm was used, and performance on orthographically similar but phonologically dissimilar pairs differed in the 2 conditions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Attentional resource demands of visual word recognition in naming and lexical decisions.

Attentional demands of lexical access were assessed with dual-task methodology. Ss performed an auditory probe task alone (single-task) or combined (dual-task) with either a lexical decision or a naming task. In Exp 1, probe performance showed a decrement from single- to dual-task conditions during recognition of words in both lexical decision and naming tasks. In addition, decrements of probe performance were larger during processing of low-frequency compared with high-frequency words in both of the word recognition tasks. Exp 2 showed that the time course of frequency-sensitive demands was similar across lexical decision and naming tasks and that attention is required early in the word recognition sequence. The results support the assumption that lexical access is both frequency sensitive and attention demanding. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Generation effects with nonwords: The role of test appropriateness.

Assessed the role of test appropriateness by studying generation effects with nonwords in 2 experiments, using 96 undergraduates. In Exp I, which used the switching of 2 letters as the generate task, Ss showed better memory for generated nonwords when the retention test assessed memory for which letters had been switched; in Exp II, a generation effect for nonwords emerged when Ss were required to generate items again at test, prior to the recognition decision. Results demonstrate that a robust generation effect can occur with meaningless items, as long as retention tests show sensitivity to what Ss actually generate in the nonword case. It is suggested that to allow for a generation effect to emerge, it is necessary to match what is actually generated with what is tested in the retention environment. (26 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Lexical access for concrete and abstract words.

Three experiments with 48 undergraduates compared the speed and accuracy of lexical decisions for concrete and abstract nouns. Results of Exp I, in which separate groups of Ss judged each word type, and of Exp II, in which all Ss judged mixed blocks of both word types, indicate that there was a small speed advantage for concrete nouns in lexical decision. To observe transfer effects from one word type to the other, all Ss in Exp III made judgments within blocked presentations of each word type. Findings show that when blocks of abstract words followed blocks of concrete words, judgments for the abstract words were significantly longer than those for concrete words. When concrete blocks followed abstract blocks, however, there was no difference in response time for the 2 word types. It is concluded that the effect of concreteness in lexical decision appears to be critically sensitive to order of presentation. Implications for models of common vs dual representation in lexical memory are discussed. (56 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Differential sensitivity of perceptual identification for words and pseudowords to test expectations: Implications for the locus of word frequency effects.

Four experiments using a study-test paradigm provide evidence of differences in the nature of perceptual enhancement effects for words compared with results for meaningless pseudowords. Ss studied words (Exps 1, 2, and 4) or pseudowords (Exps 3 and 4) presented from 1 to 6 times in a list, then performed perceptual identification tests of studied and nonstudied items. Better identification of studied than of nonstudied items (i.e., a priming effect) was found for words and nonwords, but for words the function relating enhancement to the amount of prior exposure (i.e., a repetition effect) depended on whether Ss expected a later recall test. The results support dual-process accounts of word identification that assume a flexible use of either lexical code activation or episodic trace retrieval. A framework for understanding priming, repetition, and word frequency effects is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Comparing retrieval dynamics in recognition memory and lexical decision.

The response-signal method was used to study memory retrieval in the lexical-decision (LD) and recognition-memory (RM) tasks. In Experiment 1 subjects studied mixed lists of words and nonwords and then were tested on old and new words and nonwords, under either RM or LD instructions. The earliest above-chance performance (the intercept) was shorter for LD than for RM. Repetition priming in LD appeared primarily in bias, and the only reliable RM difference between words and nonwords was a bias to respond 'old' more often to nonwords. In Experiment 2, subjects made lexical decisions to high frequency (HF) and low frequency (LF) words. LF words had a later intercept than HF words, but repetition priming largely eliminated this difference. As in Experiment 1, priming also affected LD bias. The findings have implications for several issues concerning lexical and episodic retrieval and for the ways in which the LD and RM tasks are related. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Similar attentional, frequency, and associative effects for pseudohomophones and words

Between the presentation and recall of 1 or 5 digits, Ss performed a secondary task of naming a visually presented letter string--a pseudohomophone (e.g., FOLE, HOAP) or its real-word counterpart (FOAL, HOPE). Memory load interacted with frequency (HOPE vs. FOAL, HOAP vs. FOLE) but not with lexicality (HOPE vs. HOAP, FOAL vs. FOLE). This outcome counters models in which nonwords are named by a slow (resource-expensive) process that assembles phonology and words are named by a fast (resource-inexpensive) process that accesses lexical phonology. When the associative priming-of-naming task was secondary to the memory task, pseudohomophone associative priming (HOAP-DESPAIR, FOLE-HORSE) equaled associative priming (HOPE-DESPAIR, FOAL-HORSE) and was affected in the same way by memory load. Assembled phonology seems to underlie the naming of both words and nonwords.     

Why do non-color words interfere with color naming?

In the non-color-word Stroop task, university students' response latencies were longer for low-frequency than for higher frequency target words. Visual identity primes facilitated color naming in groups reading the prime silently or processing it semantically (Experiment 1) but did not when participants generated a rhyme of the prime (Experiment 3). With auditory identity primes, generating an associate or a rhyme of the prime produced interference (Experiments 2 and 3). Color-naming latencies were longer for nonwords than for words (Experiment 4). There was a small long-term repetition benefit in color naming for low-frequency words that had been presented in the lexical decision task (Experiment 5). Facilitation of word recognition speeds color naming except when phonological activation of the base word increases response competition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)