Forward and backward repetition blindness in speed and accuracy.

Repetition blindness (RB) was investigated in a new paradigm in which effects could stem from items preceding or following a target. Speeded-response tasks were used in which 3 critical items (C1, C2, and C3) were sequentially presented on each trial. In Experiments 1 and 2, participants were asked to judge whether C2 (the target) was present on each trial. Forward RB was examined in Experiment 1 via manipulation of whether C1 and C2 were repeated and backward RB was probed in Experiment 2 via manipulation of whether C2 and C3 were repeated. RB was successfully demonstrated in both experiments: Target presence judgments were slower and less accurate with repeated conditions than with unrepeated conditions. Experiment 3 involved a semantic categorization task in which participants had to judge whether C2 was a letter or a digit. Manipulating forward and backward repetition produced reliable effects on both reaction times and accuracy. The results are consistent with the idea that RB is due to failure in token individualization rather than type refractory problems or failure in memory retrieval. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Repetition blindness has a perceptual locus: Evidence from online processing of targets in RSVP streams.

Four experiments tested whether repetition blindness (RB; reduced accuracy reporting repetitions of briefly displayed items) is a perceptual or a memory-recall phenomenon. RB was measured in rapid serial visual presentation (RSVP) streams, with the task altered to reduce memory demands. In Experiment 1 only the number of targets (1 vs. 2) was reported, eliminating the need to remember target identities. Experiment 2 segregated repeated and nonrepeated targets into separate blocks to reduce bias against repeated targets. Experiments 3 and 4 required immediate "online" buttonpress responses to targets as they occurred. All 4 experiments showed very strong RB. Furthermore, the online response data showed clearly that the 2nd of the repeated targets is the one missed. The present results show that in the RSVP paradigm, RB occurs online during initial stimulus encoding and decision making. The authors argue that RB is indeed a perceptual phenomenon. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Repetition blindness between visually different items: the case of pictures and words

Repetition blindness (RB) is the failure to see or recall the second of two visually similar or identical items in rapid serial visual presentation. It was initially demonstrated by Kanwisher (1987), who proposed that a second token of a given word or object type cannot be established when the two items occur close in time. Bavelier and Potter (1992) showed that RB also occurs between visually different items that are phonologically similar. They proposed that RB may occur not only when the targets are physically similar, but also when they have to be registered or encoded in short-term memory (STM) along dimensions on which they are similar. This hypothesis predicts that RB between visually different items should not be restricted to words, but should occur with any stimuli, as long as the task requires these stimuli to be encoded along dimensions on which they are similar. Moreover, it also implies that a task that changes the preferred code of targets will affect the size of RB. The first prediction was confirmed by establishing RB between phonologically similar pictures and words, whether semantically related (the picture of a cat and the word "cat") or not (the picture of a sun and the word "son"), when using a task that requires phonological encoding (Experiments 1 and 2). The second prediction was also supported: the magnitude of RB depended on whether the task required similar or different codes for pictures and words (Experiments 3 and 4). These experiments confirm that RB between visually different items is due to the similarity of the codes initially used in STM. The results suggest that RB can occur at any step during the instantiation of a token, arising not only from a failure to create a new token, but also from a failure to stabilize an opened token. In this view, tokens are to be seen as dynamical entities, built over time as a function of type activation and task requirements, and varying in stability as a function of the information that is entered into them.     

Masked priming from orthographic neighbors: An ERP investigation.

Two experiments combined masked priming with event-related potential (ERP) recordings to examine effects of primes that are orthographic neighbors of target words. Experiment 1 compared effects of repetition primes with effects of primes that were high-frequency orthographic neighbors of low-frequency targets (e.g., faute-faune [error-wildlife]), and Experiment 2 compared the same word neighbor primes with nonword neighbor primes (e.g., aujel-autel [altar]). Word neighbor primes showed the standard inhibitory priming effect in lexical decision latencies that sharply contrasted with the facilitatory effects of nonword neighbor primes. This contrast was most evident in the ERP signal starting at around 300 ms posttarget onset and continuing through the bulk of the N400 component. In this time window, repetition primes and nonword neighbor primes generated more positive-going waveforms than unrelated primes, whereas word neighbor primes produced null effects. The results are discussed with respect to possible mechanisms of lexical competition during visual word recognition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The use of nonword repetition as a test of phonological memory in children with Down syndrome

Recent research suggests a significant relationship between verbal short-term memory and normal language development. Although poor short-term memory and impaired language are features of Down syndrome there has been little investigation of the relationship between these functions in this population, and no studies have included the nonword repetition test devised by Gathercole and Baddeley on which much of the evidence from normal development is based. This study reports the use of nonword repetition with 33 children and teenagers with Down syndrome aged from 5 to 18 years, and investigates the relationship between this test and other memory and language measures. Word repetition was included as an indirect control for the perceptual and speech impairments often associated with this group. Words were repeated significantly more successfully than nonwords and both these tasks were sensitive to word length. Nonword repetition was significantly correlated with age, and when age and nonverbal cognitive ability were controlled, nonword repetition was significantly correlated with all other language-based memory measures, i.e. auditory digit span, word span, sentence repetition, and fluency, and also with memory for a sequence of hand movements, but not with memory for faces or a visual digit span task. There was also a significant relationship between nonword repetition and receptive vocabulary, language comprehension, and reading. When performance on the word repetition task was controlled in addition to age and nonverbal ability, significant correlations between nonword repetition and word span, sentence memory, hand movements, language comprehension, and reading remained. Fewer relationships between auditory digit span and these other measures were established; in particular, there was no association between digit span and the language and reading measures. Results suggest that nonword repetition is a reliable measure of phonological memory in Down syndrome and can predict language comprehension and reading ability.     

Long-term semantic priming of word meaning.

Three experiments investigated facilitation in synonym decisions as a function of prior synonym decision trials that were either identical or semantically related. Experiment 1 demonstrated that semantically related prime trials produced less facilitation than identical prime trials, but facilitation from both persisted over 14 intervening trials. Experiments 2 and 3 demonstrated that word meaning retrieval without meaning comparison in prime trials was sufficient for persistent facilitation in semantically related targets, and meaning comparison was necessary for repetition priming to show greater facilitation than semantic priming. Results suggest that semantic priming in this task may solely reflect strength changes in abstract semantic representations, whereas repetition priming may reflect additional nondeclarative memory for operations performed in prime events. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Young children's phonological awareness and nonword repetition as a function of vocabulary development.

The role of vocabulary growth in the development of two reading-related phonological processes was examined. In Experiments 1 and 2, 4- and 5-year-olds and a sample of first graders performed better on phonological awareness tasks for word versus pseudoword stimuli, and for highly familiar versus less familiar words. Three- and 4-year-olds in Experiment 3 performed better for words with many versus few similarly sounding items in a listener's lexicon. Vocabulary was strongly associated with nonword repetition scores for 3- to 5-year olds. The shared variance of this association was accounted for by phonological awareness measures and did not appear to be due to phonological short-term memory, as previously argued. The author proposes that vocabulary growth, defined in terms of absolute size, word familiarity, and phonological similarity relations between word items, helps to explain individual differences in emerging phonological awareness and nonword repetition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sentence context, word recognition, and repetition blindness.

When the sentence She ran her best time yet in the rice last week is displayed using rapid serial visual presentation, viewers sometimes misread rice as race (M. C. Potter, A. Moryadas,1. Abrams, & A. Noel, 1993). Seven experiments combined misreading and repetition blindness (RB) paradigms to determine whether misreading of a word because of biasing sentence context represents a genuine perceptual effect. In Experiments 1-4, misreading a word either caused or prevented RB for a downstream word, depending on whether orthographic similarity was increased or decreased. Additional experiments examined temporal parameters of misreading RB and tested the hypothesis that RB results from reconstructive memory processes. Results suggest that the effect of prior context occurs during perception. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Phonological working memory in very young children.

This study was designed to establish whether phonological working memory skills could be assessed in children below 4 yrs of age. A group of 2- and 3-yr-old children were tested on 3 phonological memory measures (digit span, nonword repetition, and word repetition) and were also given tasks that tapped other cognitive skills. Scores on the 3 phonological memory tasks were closely related. In addition, repetition performance was linked with both vocabulary knowledge and articulation rate. Results indicate that phonological memory skills can be reliably assessed in very young children by using conventional serial span and repetition procedures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Types and tokens in visual processing: A double dissociation between the attentional blink and repetition blindness.

In rapid serial visual presentation tasks, correct identification of a target triggers a deficit for reporting a 2nd target appearing within 500 ms: an attentional blink (AB). A different phenomenon, termed repetition blindness (RB), refers to a deficit for the 2nd of 2 stimuli that are identical. What is the relationship between these 2 deficits? The present study obtained a double dissociation between AB and RB. AB and RB followed different time courses (Experiments 1 and 4A), increased target-distractor discriminability alleviated AB but not RB (Experiments 2 and 4A), and enhanced episodic distinctiveness of the two targets eliminated RB but not AB (Experiments 3 and 4B). The implications of the double dissociation between AB and RB for theories of visual processing are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Repetition Blindness: Out of Sight or Out of Mind?

Does repetition blindness represent a failure of perception or of memory? In Experiment 1, participants viewed rapid serial visual presentation (RSVP) sentences. When critical words (C1 and C2) were orthographically similar, C2 was frequently omitted from serial report; however, repetition priming for C2 on a postsentence lexical decision task was equivalent whether or not C1 was similar to C2. In Experiment 2, participants monitored RSVP sentences for a predetermined target. Participants frequently failed to detect the target when it was preceded by an orthographically similar word. In Experiment 3, the authors investigated the role of the attentional blink in this effect. These experiments suggest that repetition blindness is a failure of conscious perception, consistent with predictions of the token-individuation hypothesis. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Phonological recoding of nonword orthographic rime primes.

The effectiveness of nonword orthographic rime primes as a function of the regularity (as defined by grapheme-phoneme correspondence [GPC] rules) of typical pronunciation was examined in this research. In Experiments 1 and 2, predictions from GPC and orthographic rime unit accounts converged, but in Experiments 3 and 4 they diverged. Experiment 1 showed that when nonword orthographic rimes were used to prime consistent regular words (e.g., mist) and atypically irregular words (e.g., pint), reliable priming was observed for regular words, but priming of atypically irregular words occurred only in the 2nd block of trials, after the orthographic rime prime itself had been primed by the Block 1 presentation of the target word. In subsequent experiments, only the 1st block of trials was examined. Experiment 2 replicated selective priming of consistent regular words observed in Block 1 of Experiment 1. In Experiment 3, nonword orthographic rimes were as effective at priming typically irregular target words (e.g., grind) as they were in priming inconsistent but typically regular target words (e.g., flint)… (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Masked Repetition and Phonological Priming Within and Across Modalities.

Lexical decision latencies to word targets presented either visually or auditorily were faster when directly preceded by a briefly presented (53-ms) pattern-masked visual prime that was the same word as the target (repetition primes), compared with different word primes. Primes that were pseudohomophones of target words did not significantly influence target processing compared with unrelated primes (Experiments 1-2) but did produce robust priming effects with slightly longer prime exposures (67 ms) in Experiment 3. Like repetition priming, these pseudohomophone priming effects did not interact with target modality. Experiments 4 and 5 replicated this general pattern of effects while introducing a different measure of prime visibility and an orthographic priming condition. Results are interpreted within the framework of a bimodal interactive activation model. (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)     

Phonological priming in auditory word recognition.

Used a priming technique to test specific predictions regarding cohort activation in 3 experiments involving 170 undergraduates. Ss identified target words embedded in noise at different signal-to-noise ratios. The target words were either presented in isolation or preceded by a prime item that shared phonological information with the target. In Exp I, primes and targets were English words that shared 0, 1, 2, 3, or all phonemes from the beginning of the word. In Exp II, nonword primes preceded word targets and shared initial phonemes. In Exp III, word primes and word targets shared phonemes from the end of a word. Reliable phonological priming was observed in all experiments. Results of Exps I and II support the assumption of activation of lexical candidates based on word-initial information, as proposed in cohort theory; however, results of Exp III, which showed increased probability of correctly identifying targets that shared phonemes from the end of words, did not support the predictions derived from the theory. (34 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Semantic priming in the lexical decision task: Roles of prospective prime-generated expectancies and retrospective semantic matching.

In semantic priming paradigms for lexical decisions, the probability that a word target is semantically related to its prime (the relatedness proportion) has been confounded with the probability that a target is a nonword, given that it is unrelated to its prime (the nonword ratio). This study unconfounded these two probabilities in a lexical decision task with category names as primes and with high- and low-dominance exemplars as targets. Semantic priming for high-dominance exemplars was modulated by the relatedness proportion and, to a lesser degree, by the nonword ratio. However, the nonword ratio exerted a stronger influence than did the relatedness proportion on semantic priming for low-dominance exemplars and on the nonword facilitation effect (i.e., the superiority in performance for nonword targets that follow a category name rather than a neutral XXX prime). These results suggest that semantic priming for lexical decisions is affected by both a prospective prime-generated expectancy, modulated by the relatedness proportion, and a retrospective target/prime semantic matching process, modulated by the nonword ratio. (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)     

Are individual or consecutive letters the unit affected by repetition blindness?

When 2 similar words (e.g., react reach) are briefly sequentially displayed, the 2nd word may be omitted from the report, a phenomenon known as repetition blindness (RB). Previous researchers have suggested that consecutive letters are the unit affected by RB. Six experiments provided new data on orthographic RB. Two letters at the beginning or end of words resulted in RB, as did alternating interior letters (tactile earthly) and 3 letters with different relative positions (arid bird). However, no RB was found with a single final letter (show view). Observed RB may reflect pattern completion because RB for pairs like throat theory was reduced when the nonrepeated letters (eory) were consistent with only a single word. The experiments point to a model of orthographic RB in which both individual letters and letter sequences of length 2 or more play a role. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Repetition blindness: Levels of processing.

Repetition blindness (RB) is the failure to detect or recall repetitions of words in rapid serial visual presentation. Experiment 1 showed that synonym pairs are not susceptible to RB. In Experiments 2 and 3, RB was still found when one occurrence of the word was part of a compound noun phrase. In Experiment 4, homonyms produced RB if they were spelled identically (even if pronounced differently) but not if spelled differently and pronounced the same. Similarly spelled but otherwise unrelated word pairs appeared to generate RB (Experiment 5), but Experiment 6 produced an alternative account. Experiments 7 and 8 demonstrated that repeated letters are susceptible to RB only when displayed individually, not as part of two otherwise different words. It is concluded that RB can occur at either an orthographic (possibly morphemic) level or a case-independent letter level, depending on which unit (words or single letters) is the focus of processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)