Why do semantic priming effects increase in old age? A meta-analysis.

Reports a meta-analysis comparing the size of semantic priming effects on young and older adults' lexical decision and pronunciation latency. The analysis included 15 studies with 49 conditions varying the semantic relatedness of a prime stimulus (single word or whole sentence) and a target word. An effect-size analysis on the difference between young and older adults' semantic priming effect (unrelated minus related latency) indicated that semantic priming effects are reliably larger for older than for young adults. There was no evidence for nonhomogeneity in this age difference across the different conditions. The relationship between young and older adults' semantic priming effects was described by a function with a positive intercept and a slope of 1.0. This pattern of findings favors aging models postulating process-specific slowing rather than general cognitive slowing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Automatic semantic priming: Effect of category exemplar level and word association level.

Evaluated semantic priming when the prime was masked below naming threshold and the target was named in 4 experiments with 263 undergraduates. Exp I showed that when word primes were masked and word targets were named, prior knowledge of the related pairs did not alter semantic priming. Semantic priming within categories occurred only when the prime stimulus was the 1st category exemplar. Findings of Exp II indicate that when masked pictures were used as primes, semantic priming for word targets was sensitive to the category exemplar level of the prime but not to the category exemplar level of the target. Word association norms collected in Exp III did not support the hypothesis that the effect of category exemplar level was mediated by the strength of word association. Exp IV revealed significant semantic priming for masked picture primes and within-category word targets, regardless of the level of word association between prime and target. Exp IV also demonstrated semantic priming for high word association targets that were not members of the same semantic category. For all experiments, Ss with the longest average reaction times (RTs) also showed the largest semantic priming effect for naming word targets. It is suggested that viewing one of the highest ranking category exemplars activates the memory representation of the category, perhaps because such prototypic exemplars are contained within the category concept itself. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Word-based grouping affects the prime-task effect on semantic priming.

Semantic priming between words is reduced or eliminated if a low-level task such as letter search is performed on the prime word (the prime task effect), a finding used to question the automaticity of semantic processing of words. This idea is critically examined in 3 experiments with a new design that allows the search target to occur both inside and outside the prime word. The new design produces the prime task effect (Experiment 1) but shows semantic negative priming when the target letter occurs outside the prime word (Experiments 2 and 3). It is proposed that semantic activation and priming are dissociable and that inhibition and word-based grouping are responsible for reduction of semantic priming in the prime task effect. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Constraints on the additive relationship between semantic priming and word repetition and on the interactive relationship between semantic priming and stimulus clarity.

Describes 2 experiments that manipulated priming condition, repetition, and stimulus clarity. Exp 1 with 87 undergraduates confirmed the additive relationship between semantic priming and word repetition when the time between repetitions was relatively long. Exp 2 with 82 undergraduates limited the number of intervening trials between repetitions (0, 1, 3, 7 trials). Results are interpreted as support for the position that there are 3 components to the repetition effect: sensory, lexical, and episodic. Degradation increased the repetition effect in both experiments without affecting the semantic priming effect. This was interpreted to mean that degradation had its effect late in the information processing sequence. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Adding new word associations to semantic memory: evidence for two interactive learning components

The addition of newly learned word associations to semantic memory was investigated in three experiments. In these experiments word pairs were repeatedly presented as prime-target pairs in a lexical decision task. Performance on repeated pairs (both pre-experimentally associated and initially unrelated pairs) was compared to that on neutral pairs. In Experiments 1 and 2, effects of prior study (episodic priming) were observed but since this episodic priming effect was equal for both conditions it could not be concluded that the new associations has been added to semantic memory. In Experiment 3 some evidence was found that the newly learned word associations had been added to semantic memory. This occurred only after presenting the word pairs for several trials in paired-associate learning. The results are interpreted as supporting a model that distinguishes two memory components that mediate the effects of new learning, an episodic and a semantic one.     

Priming effects in semantic classification tasks.

Six experiments were conducted on priming in semantic classification tasks that allow free play between perceptual and semantic processes. Priming was greatest when words were repeated on the same semantic task at study and test but was absent when repeated words were classified on different semantic tasks (size and man-made; Exp 1). Thus, merely repeating perceptual information is not sufficient to produce priming. Priming was obtained, however, when items on the same semantic task were repeated in different formats (words and pictures; Exp 2). Consistent with stage models of single-word reading, priming was obtained when a semantic classification task was followed by a word form task (i.e., lexical classification or naming) but not when it was preceded by the word form task (Exps 3 and 4). Priming was also found across lexical tasks that both involve the word form (Exp 5) and across classification tasks that refer to the same semantic domain (overall size and relative dimensions; Exp 6). Results suggest that priming is determined by the overlap in the component processes of the study and test tasks. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Semantic priming and Stroop-like interference in word-naming tasks.

Three studies with 72 undergraduates examined why a semantic relation between relevant and irrelevant stimulus components facilitates performance in priming tasks but seems to inhibit performance in Stroop-like tasks. In a series of word-naming tasks, the effect of number of semantic domains (varied concomitantly with number of response alternatives) was examined by presenting to Ss an identical set of stimuli either blocked or mixed. Exp I showed that blocked presentation yielded Stroop-like interference, whereas mixed presentation yielded semantic facilitation. Exps II and III showed that the word–word variant of the Stroop task and the word-naming variant of the semantic priming task belonged to 1 family of tasks. Both tasks showed a facilitation effect when the prime was related to the target and an interference effect when the prime was a member of the response set. In the Stroop task, response competition outweighed facilitation; in the priming task, semantic facilitation outweighed response competition. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Long-term semantic priming: A computational account and empirical evidence.

Semantic priming is traditionally viewed as an effect that rapidly decays. A new view of long-term word priming in attractor neural networks is proposed. The model predicts long-term semantic priming under certain conditions. That is, the task must engage semantic-level processing to a sufficient degree. The predictions were confirmed in computer simulations and in 3 experiments. Experiment 1 showed that when target words are each preceded by multiple semantically related primes, there is long-lag priming on a semantic decision task but not on a lexical-decision task. Experiment 2 replicated the long-term semantic priming effect for semantic decisions with only one prime per target. Experiment 3 demonstrated semantic priming with much longer word lists at lags of 0, 4, and 8 items. These are the first experiments to demonstrate a semantic priming effect spanning many intervening items and lasting much longer than a few seconds. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

In Search of Perceptual Priming in a Semantic Classification Task.

Four experiments tested for perceptual priming for written words in a semantic categorization task. Repetition priming was obtained for low-frequency words when unrelated categorizations were performed at study and test (Experiment 1), but it was not orthographically mediated given that written-to-written and spoken-to-written word priming was equivalent (Experiments 2 and 3). Furthermore, no priming was obtained between pictures and words (Experiment 4), suggesting that the nonorthographic priming was largely phonological rather than semantic. These results pose a challenge to standard perceptual theories of priming that should expect orthographic priming when words are presented in a visual format at study and test. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Attention and semantic priming: a review of prime task effects

The single-word semantic priming paradigm is a tool for investigating how and when word meaning (semantic) activation occurs during visual word recognition. The prime task effect refers to the elimination of the typically robust semantic priming effect by a nonsemantic prime task (e.g., subjects search the prime word for a letter). The purpose of this paper is to provide a tutorial review of the literature examining the prime task effect. Understanding the nature of this effect has implications for delineating how selective attention modulates evidence for semantic activation during word reading. These implications are outlined. Additionally, speculations for how these issues of selective attention relate to awareness are offered.     

Integrative priming occurs rapidly and uncontrollably during lexical processing.

Lexical priming, whereby a prime word facilitates recognition of a related target word (e.g., nurse → doctor), is typically attributed to association strength, semantic similarity, or compound familiarity. Here, the authors demonstrate a novel type of lexical priming that occurs among unassociated, dissimilar, and unfamiliar concepts (e.g., horse → doctor). Specifically, integrative priming occurs when a prime word can be easily integrated with a target word to create a unitary representation. Across several manipulations of timing (stimulus onset asynchrony) and list context (relatedness proportion), lexical decisions for the target word were facilitated when it could be integrated with the prime word. Moreover, integrative priming was dissociated from both associative priming and semantic priming but was comparable in terms of both prevalence (across participants) and magnitude (within participants). This observation of integrative priming challenges present models of lexical priming, such as spreading activation, distributed representation, expectancy, episodic retrieval, and compound cue models. The authors suggest that integrative priming may be explained by a role activation model of relational integration. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Levels of selection and capacity limits.

Examined the effects of word relevancy (word in relevant or irrelevant location) and display load (1–4 words) on physical, semantic, and controlled processing of nontargets in visual target-detection tasks administered to 300 undergraduates in 8 experiments. Interwoven with the detection task was a test-word identification task that was used to measure priming potency of nontargets. Physical and semantic levels of processing were measured in terms of identity and semantic priming, respectively. Nontarget primes were repeated as test words in identity priming. Nontarget primes were semantic associates of test words in semantic priming. Controlled processing of nontargets was measured in terms of recognition memory on a subsequent test. All measures increased with word relevancy and decreased with display load. The priming effects remained intact even when word presentation was speeded up and controlled processing was sharply curtailed. Data indicate that all levels of processing are selective and capacity limited. (60 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

When are morphemic and semantic priming observed in visual word recognition?

J. Stolz and D. Besner (1998) reported a dissociation between morphemic and semantic priming in the context of lexical decision. Morphemic priming was observed following letter search on the prime display, but semantic priming was not. The 14 participants in the present experiment identified the color of a single letter in the prime display before making a lexical decision to the target. Both morphemic and semantic priming were observed. These results are discussed in relation to the observation that identifying the color of a single letter of a word in the Stroop task is associated with a reduction in the size of the Stroop effect as compared to when all letters are colored. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mechanisms of unconscious priming: I. Response competition, not spreading activation.

Four experiments were conducted to replicate and expand upon A. G. Greenwald, S. C. Draine, and R. L. Abram's (1996) demonstration that unconsciously perceived priming words can influence judgments of other words. The present experiments manipulated 2 types of relationships between priming and target stimuli: (a) whether priming and target stimuli possess a preexisting semantic relationship (an affective relationship in Experiments 1, 2, and 4; an associative relationship in Experiment 3; and an animacy relationship in Experiment 4) and (b) whether the primes and targets produce the same response. Large priming effects were found only when the primes and targets possessed response compatibility. No residual effects for affective, animacy, or semantic relatedness were observed. Although these results strongly support the conclusion that word meaning can be unconsciously activated, they do not support the claim that the unconscious perception effects obtained in Greenwald et al.'s (1996) paradigm are caused by automatic spreading activation of word meaning. Instead, the results reported here are consistent with a claim that unconsciously perceived words automatically trigger response tendencies that facilitate or interfere with target responding. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Blinks of the mind: Memory effects of attentional processes.

If 2 words are presented successively within 500 ms, subjects often miss the 2nd word. This attentional blink reflects a limited capacity to attend to incoming information. Memory effects were studied for words that fell within an attentional blink. Unrelated words were presented in a modified rapid serial visual presentation task at varying stimulus-onset asynchronies, and attention was systematically manipulated. Subsequently, recognition, repetition priming, and semantic priming were measured separately in 3 experiments. Unidentified words showed no recognition and no repetition priming. However, blinked (i.e., unidentified) words did produce semantic priming in related words. When, for instance, ring was blinked, it was easier to subsequently identify wedding than apple. In contrast, when the blinked word itself was presented again, it was not easier to identify than an unrelated word. Possible interpretations of this paradoxical finding are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Levels of representation in visual word recognition: a dissociation between morphological and semantic processing

A robust semantic priming effect typically occurs in visual word recognition if the prime is read before a response to the target. However, this effect is dramatically reduced if a letter search is performed on the prime prior to responding to the target. Three lexical decision experiments document the new observation that morphological priming is preserved following letter search on the prime. This dissociation between morphological and semantic priming following letter search can be understood in the context of an interactive activation framework. In addition, the implications of these results for connectionist and compound cue accounts of word recognition, as well as the issue of automaticity in word recognition, are discussed.     

Interactive Activation in Visual Word Recognition: Constraints Imposed by the Joint Effects of Spatial Attention and Semantics.

Two lexical-decision experiments investigated the effects of semantic priming and stimulus intensity when target location varied and was cued by an abrupt onset. In Experiment 1, the spatial cue was a good predictor of target location, and in Experiment 2 it was not. The results indicate that word recognition processes were postponed until spatial attention was focused on the target and that whether attention further affected word recognition depended on cue validity. The joint effects of cue validity and priming interacted when cue validity was high but were additive when cue validity was low. The joint effects of stimulus intensity and semantic priming also varied according to cue validity (i.e., interactive when high and additive when low). The results are discussed in terms of their implications for visual word recognition, the distinction between exogenous and endogenous spatial attention, and how attention is affected by visual word recognition processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

How semantic is automatic semantic priming?

Priming for semantically related concepts was investigated using a lexical decision task designed to reveal automatic semantic priming. Two experiments provided further evidence that priming in a single presentation lexical decision task (T. P. McNamara and J. Altarriba, 1988) derives from automatic processes. Mediated priming, but not inhibition or backward priming, was found in this type of lexical decision task. Exps 3 and 4 demonstrate that automatic priming was found only for associated word pairs, as determined by word association norms, and not for word pairs that are semantically related but not associated. It is argued that automatic priming in the lexical decision task occurs at a lexical level but not at a semantic level. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Semantic priming in major depressive state

We studied semantic priming in 20 major depressive subjects. The methodology used was a visual lexical decision task. Semantic priming is the facilitation of target word recognition (shortening of response time) by the prior presentation of a semantically related context (a prime word). It relies on semantic processing of words and context, facilitating early cognitive stages of response. Varying the temporal interval between prime and target words onset allows us to distinguish between two priming mechanisms, relying on more automatic (test 1) or more controlled (i.e. attention dependent) (test 2) information processing. We observe a significant retardation for words and pseudo-words in depressives (in relation to controls) in both tests. In spite of a general retardation and increase of response times in depressives, semantic priming is evident in both groups and both tests, and does not differ significantly between depressive and control groups in either automatic or controlled conditions. Theses results confirm that semantic processing is not impaired in depression, and are discussed with regard to the hypothesis of an effortful processing impairment in depression, and to depressive retardation.     

Attention constraints of semantic activation during visual word recognition.

The reduction of semantic priming following letter search of the prime suggests that semantic activation can be blocked if attention is allocated to the letter level during word processing. Is this true even for the very fast-acting component of semantic activation? To test this, the authors explored semantic priming of lexical decision at stimulus onset asynchronies (SOAs) of either 200 or 1000 ms. Following semantic prime processing, priming occurred at both SOAs. In contrast, no priming occurred at the long SOA following letter-level processing. Of greatest interest, at the short SOA there was priming following the less demanding consonant/vowel task but not following the more attention-demanding letter search task. Hence, semantic activation can occur even when attention is directed to the letter level, provided there are sufficient resources to support this activation. The authors conclude that the default setting during word recognition is for fast-acting activation of the semantic system. (PsycINFO Database Record (c) 2010 APA, all rights reserved)