Perceptual and Conceptual Priming of Individual Words in Coherent Texts

This study explores implicit memory within the domain of text processing. Three experiments were designed to study priming in word-fragment completion, wordstem completion, and free association tests following presentation of target words in the context of a coherent text. In order to examine the time course of perceptual and conceptual processes we investigated the priming effects by manipulating the perceptual context in which the target words had been read and the time given to the subjects for each test-cue. Three main results emerged. First, we found a significant priming effect in the three implicit tests for words previously studied in a text. Second, the magnitude of the priming effect only varied when the task demands required perceptual and conceptual processing, as was the case with the completion tests. Third, priming effects did not depend on subjects' comprehension of the text read. These results are discussed in the framework of the transfer appropriate processing view proposed by Roediger, Weldon, and Challis (1989).     

Cross-modality priming for individual words in memory for coherent texts

This study explores implicit memory within the domain of text processing. Three experiments were designed to study cross-modality priming in a word-stem completion test following presentation of target words in the context of a coherent text. Four main results emerged. First, we found a significant priming effect for words previously studied in a text, this priming is higher with low-frequency words than with high-frequency words. Second, subjects demonstrated more repetition priming when study and test modalities matched than when they were different. Third, the magnitude of the priming effect in the visual condition varied with the perceptual processing of the text read. Fourth, priming effects did not depend on subjects' remembering of the words of text read as measured by a yes/no recognition test since no modality effect was found in this latter memory test. These results challenge Levy's (1993) view and are discussed in the framework of the transfer-appropriate processing view proposed by Roediger, Weldon and Challis (1989).     

Perceptual and conceptual priming of individual words in coherent texts.

This study explores implicit memory within the domain of text processing. Three experiments were designed to study priming in word-fragment completion, word-stem completion, and free association tests following presentation of target words in the context of a coherent text. In order to examine the time course of perceptual and conceptual processes we investigated the priming effects by manipulating the perceptual context in which the target words had been read and the time given to the subjects for each test-cue. Three main results emerged. First, we found a significant priming effect in the three implicit tests for words previously studied in a text. Second, the magnitude of the priming effect only varied when the task demands required perceptual and conceptual processing, as was the case with the completion tests. Third, priming effects did not depend on subjects' comprehension of the text read. These results are discussed in the framework of the transfer-appropriate processing view proposed by Roediger, Weldon, and Challis (1989).     

Auditory and visual word-stem completion: Separating data-driven and conceptually driven processes

Two experiments investigated the contributions of data-driven and conceptually driven processing on an implicit word-stem completion task. In Experiment 1, individual words were studied either visually or auditorily and were tested using either visual or auditory word-stems. Keeping modality the same from study to test led to more priming than did changing modality, but there was reliable cross-modal priming. In Experiment 2, subjects read sentences like The boat travelled underwater and inferred the subject noun (i.e. “submarine”) or sentences like The submarine travelled underwater and categorized the subject noun (i.e. “boat”). At test, there was reliable priming for both actually read nouns and inferred nouns. In addition, a modality effect was evident for the actually read nouns but not for the inferred nouns. Taken together, these results imply that there is a basic conceptually driven contribution to priming plus an additional contribution of data-driven processing when surface form is the same at study and test.     

Feeling the past: The absence of experimental evidence for anomalous retroactive influences on text processing

In two self-paced reading experiments, we investigated the hypothesis that information moves backward in time to influence prior behaviors (Bem Journal of Personality and Social Psychology 100:407?C425, 2011a). In two of Bem??s experiments, words were presented after target pictures in a pleasantness judgment task. In a condition in which the words were consistent with the emotional valence of the picture, reaction times to the pictures were significantly shorter , as compared with a condition in which the words were inconsistent with the emotional valence of the picture. Bem Journal of Personality and Social Psychology 100:407?C425, (2011a) interpreted these results as showing a ??retroactive priming?? effect resulting from precognition. To test the precognition hypothesis, we adapted a standard repetition priming paradigm from psycholinguistics. In the experiments, participants read a set of texts. In one condition, the participants read the same text twice. In other conditions, participants read two different texts. The precognition hypothesis predicts that readers who encounter the same text twice will experience reductions in processing load during their first encounter with the text. Hence, these readers' average reading times should be shorter than those of readers who encounter the target text only once. Our results indicated that readers processed the target text faster the second time they read it. Also, their reading times decreased as their experience with the self-paced reading procedure increased. However, participants read the target text equally quickly during their initial encounter with the text, whether or not the text was subsequently repeated. Thus, the experiments demonstrated normal repetition priming and practice effects but offered no evidence for retroactive influences on text processing.     

Priming and aging: further evidence of preserved memory function

Priming effects in word-stem completion were compared with cued recall in young and older adults. Cued recall showed large effects of age and also of levels of processing, but these variables had little influence on priming in word-stem completion. Free recall showed large effects of age as well as superior recall for words that had been generated rather than read at study, but priming in word-stem completion was little influenced by age, and it was greater for words that had been read at study rather than generated. These findings were interpreted as providing further evidence that age-related impairments in memory performance are greatly reduced in implicit compared with explicit tests. They also provide convergent evidence for classifying word-stem completion as a data-driven rather than conceptually driven task.     

The unbearable lightness of priming

Repetition priming from text to isolated words has been difficult to observe. One explanation for this difficulty is that previous attempts to observe this type of priming have utilised conditions that normally reduce priming. Two experiments were conducted to evaluate this hypothesis. Experiment 1 involved participants being presented with words in isolation and in text passages. The words were then presented again in a lexical decision test. Results indicated that priming occurred as a result of exposure to both isolated words and words in text, although priming was greater in the word-word condition. Experiment 2 investigated whether priming occurred in a lexical decision test on words that had been read prior to the test in Milan Kundera's novel "The Unbearable Lightness of Being." There was some evidence that participants who had read the book recently were faster at lexical decision to words from the book than participants who had not read the book. The two experiments therefore indicate that priming can occur from text to isolated words, although it is smaller in magnitude to that observed from word to word. Reasons for this difference, as suggested by Kirsner and Speelman (J. Exp. Psychol.: Learn. Mem. Cogn. 22 (1996) 563) model of repetition priming, are discussed.     

The effects of unvocalized music on short-term memory

The studies reported here investigated the role of background music in verbal processing. The experiment was a partial replication of Salame and Baddeley (1989), where the effect of music on the recall of digits, was examined, but included an additional key condition where participants heard instrumental music without the words usually associated with it. In this case we used nursery rhymes. In addition, articulatory suppression was manipulated as a tool to look at the role of working memory in the task. The relationship between long-term memory and working memory was further explored by using an implicit memory task to examine verbal memory effects for words associated with the music but not actually heard. The results indicated that background, instrumental music, long-associated with words, significantly impairs concurrent verbal processing. These long-term memory effects on working memory were, however, not associated with implicit memory effects, and no priming was observed.     

The effects of unvocalized music on short-term memory

The studies reported here investigated the role of background music in verbal processing. The experiment was a partial replication of Salame and Baddeley (1989), where the effect of music on the recall of digits, was examined, but included an additional key condition where participants heard instrumental music without the words usually associated with it. In this case we used nursery rhymes. In addition, articulatory suppression was manipulated as a tool to look at the role of working memory in the task. The relationship between long-term memory and working memory was further explored by using an implicit memory task to examine verbal memory effects for words associated with the music but not actually heard. The results indicated that background, instrumental music, long-associated with words, significantly impairs concurrent verbal processing. These long-term memory effects on working memory were, however, not associated with implicit memory effects, and no priming was observed.     

Effects of thematic and lexical priming on readers' eye movements

The study was inspired by Ehrlich & Rayner (1981). In the study semantic context effects were investigated during on-line discourse processing. Readers' eye movements were registered to see whether words that were semantically closely related to the global theme of the text were read faster than words that did not have any apparent semantic link to the discourse theme. In addition, lexical priming was examined by presenting an identity prime earlier in the text. The results showed that non-thematic words were regressed to more often than thematic words. Regressions were typically initiated after reaching a clause or sentence boundary. Regressions were thus assumed to be made in order to integrate non-thematic words into the previous context. Modest negative correlations were found between word's fixation time and its relative predictability. No effects of lexical priming were observed. It was concluded that moderately constraining discourse contexts produce negligible effects on word recognition.     

Taking the “text” out of context effects in repetition priming of word identification

Repetition priming of masked word identification is reduced when initial exposure to target words is in a text rather than in a word list. We demonstrate that there is nothing special about the text context that reduces priming. In Experiment 1, target words read in normal text or in rapid serial visual presentation (RSVP) text--either coherent or scrambled--produced similarly reduced priming, relative to the same words read aloud in a list. In Experiment 2, the delay was decreased between study and test for words presented in text, but they still displayed less priming than did words presented in a study list and tested after an equivalent delay. In Experiment 3, presenting study list words in RSVP to prevent reading each word aloud diminished priming to the same level as that in the text context. We conclude that presenting a target in context prevents it from being encoded and responded to as distinctively as when presented in isolation.     

Word recognition during reading: The interaction between lexical repetition and frequency

Memory studies utilizing long-term repetition priming have generally demonstrated that priming is greater for low-frequency than for high-frequency words and that this effect persists if words intervene between the prime and the target. In contrast, word-recognition studies utilizing masked short-term repetition priming have typically shown that the magnitude of repetition priming does not differ as a function of word frequency and does not persist across intervening words. We conducted an eyetracking-while-reading experiment to determine which of these patterns more closely resembles the relationship between frequency and repetition during the natural reading of a text. Frequency was manipulated using proper names that were either high-frequency (e.g., Stephen) or low-frequency (e.g., Dominic). The critical name was later repeated in the sentence, or a new name was introduced. First-pass reading times and skipping rates on the critical name revealed robust repetition-by-frequency interactions, such that the magnitude of the repetition-priming effect was greater for low-frequency than for high-frequency names. In contrast, measures of later processing showed effects of repetition that did not depend on lexical frequency. These results are interpreted within a framework that conceptualizes eye-movement control as being influenced in different ways by lexical- and discourse-level factors.     

Comparing different kinds of words and word-word relations to test an habituation model of priming

Huber and O'Reilly (2003) proposed that neural habituation exists to solve a temporal parsing problem, minimizing blending between one word and the next when words are visually presented in rapid succession. They developed a neural dynamics habituation model, explaining the finding that short duration primes produce positive priming whereas long duration primes produce negative repetition priming. The model contains three layers of processing, including a visual input layer, an orthographic layer, and a lexical-semantic layer. The predicted effect of prime duration depends both on this assumed representational hierarchy and the assumption that synaptic depression underlies habituation. The current study tested these assumptions by comparing different kinds of words (e.g., words versus non-words) and different kinds of word-word relations (e.g., associative versus repetition). For each experiment, the predictions of the original model were compared to an alternative model with different representational assumptions. Experiment 1 confirmed the prediction that non-words and inverted words require longer prime durations to eliminate positive repetition priming (i.e., a slower transition from positive to negative priming). Experiment 2 confirmed the prediction that associative priming increases and then decreases with increasing prime duration, but remains positive even with long duration primes. Experiment 3 replicated the effects of repetition and associative priming using a within-subjects design and combined these effects by examining target words that were expected to repeat (e.g., viewing the target word ‘BACK' after the prime phrase ‘back to'). These results support the originally assumed representational hierarchy and more generally the role of habituation in temporal parsing and priming.     

The mnemonic value of perceptual identification

In four experiments, subjects were required to name words presented on a CRT screen. On generate trials, the words were presented quickly, at a point where roughly half could be identified correctly; on read trials, the items were presented for a full second, allowing for rapid and easy naming. A surprise recognition test for the presented items then revealed a substantial retention advantage for the briefly presented items, but no similar advantage was produced in a recall. It is argued that under rapid viewing conditions subjects may fail to extract enough visual features to allow for immediate resolution, requiring the initiation of a kind of data-driven generation process. This latter process then produces a generation effect for the briefly presented items compared with the read items, but only on a retention test that shows sensitivity to data-driven processing. These results are discussed from the standpoint of current theoretical views on the generation effect.     

The role of selective attention in perceptual and affective priming

Two kinds of perceptual priming (word identification and word fragment completion), as well as preference priming (that may rely on special affective mechanisms) were examined after participants either read or named the colors of words and nonwords at study. Participants named the colors of words more slowly than the colors of nonwords, indicating that lexical processing of the words occurred at study. Nonetheless, priming on all three tests was lower after color naming than after reading, despite evidence of lexical processing during color naming shown by slower responses to words than to nonwords. These results indicate that selective attention to (rather than the mere processing of) letter string identity at study is important for subsequent repetition priming.     

The crucial roles of stimulus matching and stimulus identity in negative priming

Negative priming refers to the situation in which an ignored item on an initial prime trial suffers slowed responding when it becomes the target item on a subsequent probe trial. In this experiment (and a replication), we demonstrate two ways in which stimulus consistency (matching) governs negative priming. First, negative priming for identical words occurred only when the prime distractor changed color when it became the probe target (i.e., constant cue to read the red word); negative priming disappeared when the prime distractor retained its color as the probe target (i.e., cue switches from read the red prime word to read the white probe word). Second, negative priming occurred for identical words, but not for semantically related words, whether related categorically or associatively. This pattern of results is consistent with a memory retrieval account, but not with an inhibition account of negative priming, and casts doubt on whether there is semantic negative priming for words.     

Lexical processing during saccades in text comprehension

We asked whether people process words during saccades when reading sentences. Irwin (1998) demonstrated that such processing occurs when words are presented in isolation. In our experiment, participants read part of a sentence ending in a high- or low-frequency target word and then made a long (40°) or short (10°) saccade to the rest of the sentence. We found a frequency effect on the target word and the first word after the saccade, but the effect was greater for short than for long saccades. Readers therefore performed more lexical processing during long saccades than during short ones. Hence, lexical processing takes place during saccades in text comprehension.     

联想启动与知觉启动的比较研究

采用快速命名方法探讨不同加工水平对联想启动效应的影响。被试分别在深、浅加工条件下学习一系列颜色词,然后完成颜色命名和再认任务,并设立词命名任务,以比较联想启动和知觉启动的异同。结果表明,在颜色命名任务中,深、浅加工条件下均可形成对颜色词的启动效应,但浅加工条件下的再认成绩明显低于深加工,出现了联想启动和再认的分离现象。词命名表现出与颜色命名相似的结果,但它们在有意识回忆方面仍存在一定的差异,提示知觉表征系统单独并不能支持联想启动,联想启动可能是多个记忆系统共同作用的结果。     

Conjoint dissociations reveal involuntary "perceptual" priming from generating at study.

Incidental perceptual memory tests reveal priming when words are generated orally from a semantic cue at study, and this priming could reflect contamination by voluntary retrieval. We tested this hypothesis using a generate condition and two read conditions that differed in depth of processing (read-phonemic vs read-semantic). An intentional word-stem completion test showed an advantage for the read-semantic over the generate condition and an advantage for the generate over the read-phonemic condition, and completion times were longer than in a control test, prior to which there was no study phase. An incidental word-stem completion test showed equivalent priming for the read-semantic and read-phonemic study conditions, despite considerable power, and completion times were no longer than control, indicating that retrieval was involuntary, and insensitive to prior conceptual processing. The generate condition produced less priming than the read conditions, but significant priming nonetheless. The results show that priming from generating can be involuntary and suggest that lexical processes are responsible. They are also the first results conjointly showing a crossed double dissociation, a single dissociation, and a parallel effect across memory tests with identical physical retrieval cues.     

The influence of multiple readings on the missing-letter effect revisited

In searching for a target letter while reading, participants make more omissions when the target letter is embedded in frequent function words than when it is embedded in less frequent content words. According to the guidance-organization (GO) model, this occurs because high-frequency function words are processed faster than low-frequency content words, leaving less time available for letter processing. We tested this hypothesis in three experiments by increasing word-processing speed through text repetition, which should translate into higher omission rates. Participants either read the text and searched for the target letter once or read the text three times and searched for a target letter on all readings or the final reading only. In all the experiments in which participants could not anticipate the target letter to be used, results revealed the presence of a large missing-letter effect that was unaffected by familiarity with the text. In addition, when participants knew from the start the target letter to be used on the final reading, the missing-letter effect was eliminated. Repeated search of the same text for different targets increased omissions equally for function words and content words, but this finding was present even when a new text was used, suggesting that repetition of the search task, rather than familiarity with the text, was responsible.