Semantic priming in the prime task effect: Evidence of automatic semantic processing of distractors

The automaticity of the semantic processing of words has been questioned because of the reduction of semantic priming when the prime word is processed nonsemantically--for example, in letter search (the prime task effect). In two experiments, prime distractor words produced semantic priming in a subsequent lexical decision task, but with the direction of priming (positive or negative) depending on the prime task. Lexico-semantic tasks produced negative semantic priming, whereas letter search produced positive semantic priming. These results are discussed in terms of task-based inhibition. We argue that, given the results from the distractors, the absence of semantic priming does not indicate an absence of semantic activation but reflects the action of control processes on prepotent responses when less practiced responses are needed.     

Negative priming depends on prime-probe similarity: Evidence for episodic retrieval

It is well established that requiring a person to respond to a recently ignored object in a visual selection task leads to slower responding (i.e., negative priming). In the present experiment, subjects identified target letters flanked by incompatible distractor letters on prime and probe displays. Prime display distractors appeared as the target letter on one third of subsequent probe displays. We manipulated stimulus strength by means of intensity contrast between letter displays and their background. Displays were presented with either high contrast (white against a black background) or low contrast (dark gray against a black background). The important finding was that negative priming was maximal when prime and probe displays shared the same intensity contrast. These results suggest that greater similarity between prime and probe displays results in improved retrieval of prime display information. The results provide strong support for an episodic retrieval account of negative priming.     

Interference and negative priming from ignored distractors: The role of selection difficulty

The relation between distractor interference and negative priming from identical distractors was examined in two experiments. Subjects responded to a target letter, which was indicated by an adjacent bar marker, and attempted to ignore a distracting letter. Onprime trials, distracting letters were either compatible or incompatible with the target, allowing for a measure of interference. On subsequentprobe trials, previously ignored distractors were sometimes presented as targets, allowing for a measure of negative priming. Reducing the spatial separation between targets and distractors on the prime trial increased the magnitude of interferenceand negative priming, but these effects appeared to be independent of each other (Experiment 1). In Experiment 2, the prime target location was precued on some trials, but not on others. Precuing attenuated the magnitude of interference, but not that of negative priming effects. This pattern indicates that measures of negative priming and measures of distractor interference on the immediately preceding trial are independent. The results are discussed in terms of a selective inhibition model of selective attention.     

Negative priming and perceptual fluency: more than what meets the eye

In two priming experiments, we manipulated the perceptual quality of the target or the distractor on the prime trial; the stimuli were repeated or novel. Negative priming was found to be contingent on stimulus repetition, because it was obtained with repeated items but not with novel items. Prime trial perceptual degradation modulated negative priming for repeated items but had no effect on priming in ignored repetition conditions using novel stimuli. These patterns were obtained even when the effect of perceptual degradation was (1) greater than the effect of stimulus repetition and (2) greater for novel words than for repeated words. Although stimulus repetition increases perceptual fluency, the activation of perceptual representations by itself is not sufficient to produce negative priming. Instead, we suggest that negative priming is a manifestation of an activation-sensitive inhibitory mechanism that functions to reduce response competition.     

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.     

Retrieval of incidental stimulus-response associations as a source of negative priming

Priming effects of ignored distractor words were investigated in a task-switching situation that allowed an orthogonal variation of priming and response compatibility between prime and probe. Across 3 experiments, the authors obtained a disordinal interaction of priming and response relation. Responding was delayed in the ignored repetition condition if different responses were required for identical stimuli in the prime and probe (negative priming). Repeating the prime distractor in the probe facilitated responding if the same response was required in the prime and in the probe (positive priming). The same pattern of results was replicated in a letter-matching task without task switching (Experiment 4). Findings lend support to a new model that explains negative priming in terms of an automatic retrieval of incidental stimulus-response associations.     

Negative priming without probe selection

Responses to an object may be slower or less accurate if that object shares attributes with a recently ignored object(negative priming). Some studies have found negative priming only if the probe trial required selection against a distractor stimulus. In the present experiment, subjects responded to the location of a target (O), ignoring a distractor (X) if it appeared in another location. Reaction time was slower to probe targets that appeared in the same location as the prime distractor, regardless of whether or not the probe target was accompanied by a distractor.     

Dissociative prime-probe contextual similarity effects on negative priming and repetition priming: a challenge to episodic retrieval as a unified account of negative priming

This study examined the dependence of repetition priming (RP) and negative priming (NP) as a function of prime-probe contextual similarity in a paradigm in which participants were required to respond to a letter flanked by incompatible distractor letters (e.g., ABA). Experiment 1 used prime and probe displays containing a pair of "+" symbols that were presented horizontally or vertically. Experiments 2 and 3 manipulated whether the letter triplets contained the "!" symbol. In all experiments, regardless of whether the RP trials were intermixed with the NP trials (Experiment 2) or not (Experiment 3), RP was stronger in the prime-probe similar conditions than in the prime-probe dissimilar conditions, but NP was independent of prime-probe contextual similarity. These findings suggest that NP is not necessarily stronger in conditions in which episodic retrieval of the prime is more likely.     

Locus of single-prime negative priming: The role of perceptual form

Single-prime negative priming refers to the phenomenon in which after a single prime word is briefly presented, repeating it as the probe target results in a delay in responding to the target. The present study investigated the locus of this negative priming effect. Experiment 1 showed that repeating the identity of the prime produced a negative priming effect but merely repeating the response of the prime did not. Experiment 2 showed that the negative priming effect transformed into positive priming when the probe distractor was absent. Experiments 3 and 4 further revealed that single-prime negative priming was observed when the perceptual form was repeated. Taken together, these results suggest that single-prime negative priming involves a perceptual locus.     

Letter-position coding in random consonant arrays

The processing of letter-position information in randomly arranged consonant strings was investigated using a masked prime variant of the alphabetic decision (letter/nonletter classification) task. In Experiment 1, primes were uppercase consonant trigrams (e.g., FMH) and targets were two uppercase Xs accompanied by the target letter or a nonletter (e.g., XMX, X%X). Response times were systematically faster when target letters were present in the prime string than when target letters were not present in the prime string. These constituent letter-priming effects were significantly stronger when the target letter appeared in the same position in the prime and target stimuli. This contrast between position-specific and position-independent priming was accentuated when subjects responded only when all the characters in the target string were letters (multiple alphabetic decision) in Experiments 2 and 3. In Experiment 4, when prime exposure duration was varied, it was found that position-specific priming develops earlier than position-independent priming. Finally, Experiment 5 ruled out a perceptual-matching interpretation of these results. An interpretation is offered in terms of position-specific and position-independent letter-detector units in an interactiveactivation framework.     

Single‐prime negative priming in the shape‐matching task: Implications for the role of perceptual segmentation processes

Using the shape‐matching task developed by DeSchepper and Triesman (1996), Loula, Kourtzi, and Shiffrar (2000) demonstrated that negative priming only occurred in that task when minimal segmentation cues were available in the prime display. Loula et al. (2000) interpreted their results as revealing that negative priming in the shape‐matching task is directly caused by difficulty in segmenting the prime target from the prime distractor. We offer an alternative interpretation of their results, suggesting that a failure to observe negative priming when segmentation cues are present was incidental to the perceptual segmentation process. Instead, we provide evidence suggesting that an easier perceptual segmentation task contributes positive priming influences that makes a negative priming effect more difficult to observe. Once these positive priming influences are removed, we observed negative priming both when the perceptual segmentation task is trivial and when perceptual segmentation is not a component of the prime task at all.     

The Effects of Cueing Target Location and Response Mode on Interference and Negative Priming Using a Visual Selection Paradigm

Two experiments are reported that examine the effects of cueing the location of a target in the prime display on interference and subsequent negative priming. The prime and probe displays comprised two words, a target and a distractor. In the prime display, the two words were either the same (response compatible) or different (response incompatible). The target in the probe display was unrelated to the prime distractor (control), the same word as the distractor (ignored repetition), or semantically related to the distractor (ignored semantic repetition). In Experiment 1, cueing the location of the prime target significantly reduced the interference effect but not the subsequent identity negative priming (NP) effect. In contrast, not cueing the prime target resulted in the elimination of the identity NP. There was no evidence of semantic NP in this experiment. In Experiment 2, where a categorization response was required, significant interference was obtained in the prime display that was not influenced by cueing the location of the target. Although there was significant semantic NP, identity NP failed to reach significance. The two experiments were analysed together, and findings are discussed in relation to current models of negative priming.     

Contextual modulation of prime response retrieval processes: Evidence from auditory negative priming

Contextual similarity between learning and test phase has been shown to be beneficial for memory retrieval. Negative priming is known to be caused by multiple processes; one of which is episodic retrieval. Therefore, the contextual similarity of prime and probe presentations should influence the size of the negative priming effect. This has been shown for the visual modality. In Experiment 1, an auditory four-alternative forced choice reaction time task was used to test the influence of prime-probe contextual similarity on negative priming and the processes underlying the modulation by context. The negative priming effect was larger when the auditory context was repeated than when it was changed from prime to probe. The modulation by context was exclusively caused by an increase in prime response retrieval errors in ignored repetition trials with context repetition, whereas repeating only the context but not the prime distractor did not lead to an increase in prime response retrieval. This exact pattern of results was replicated in Experiment 2. The findings suggest that contextual information is integrated with prime distractor and response information. Retrieval of the previous episode, including prime distractor, prime response, and context (event file), can be triggered when the former prime distractor is repeated, whereas a context cue alone does not retrieve the event file. This suggests an event file structure that is more complicated than its usually assumed binary structure.     

Semantic priming effects from single words in a lexical decision task

The present research examines the semantic priming effects of a centrally presented single prime word to which participants were instructed to either "attend and remember" or "ignore". The prime word was followed by a central probe target on which the participants made a lexical decision task. The main variables manipulated across experiments were prime duration (50 or 100 ms), the presence or absence of a mask following the prime, and the presence (or absence) and type of distractor stimulus (random set of consonants or pseudowords) on the probe display. There was a consistent interaction between the instructions and the semantic priming effects. Relative to the "attend and remember" instruction, an "ignore" instruction produced reduced positive priming from single primes presented for 100 ms, irrespective of the presence or absence of a prime mask, and regardless of whether the probe target was presented with or without distractors. Additionally, reliable negative priming was found from ignored primes presented for briefer durations (50 ms) and immediately followed by a mask. Methodological and theoretical implications of the present findings for the extant negative priming literature are discussed.     

The role of selection in generating auditory negative priming

The importance of selecting between a target and a distractor in producing auditory negative priming was examined in three experiments. In Experiment 1, participants were presented with a prime pair of sounds, followed by a probe pair of sounds. For each pair, listeners were to identify the sound presented to the left ear. Under these conditions, participants were especially slow to identify a sound in the probe pair if it had been ignored in the preceding prime pair. Evidence of auditory negative priming was also apparent when the prime sound was presented in isolation to only one ear (Experiment 2) and when the probe target was presented in isolation to one ear (Experiment 3). In addition, the magnitude of the negative priming effect was increased substantially when only a single prime sound was presented. These results suggest that the emergence of auditory negative priming does not depend on selection between simultaneous target and distractor sounds.     

The effect of asymmetrical association on positive and negative semantic priming

One's actively ignoring a stimulus can impair subsequent responding to that stimulus. This negative priming effect has been argued to generalize to semantically related items as well, but the evidence for this is still somewhat weak. This article presents a new experiment in which participants made lexical decisions to asymmetrically associated prime-target pairs presented in either the forward (e.g., stork-baby) or backward (e.g., baby-stork) direction. The critical new finding was that both attended positive and ignored negative semantic priming occurred only for prime-target pairs presented in the forward direction. The results support either (1) a spreading inhibition model in which items associated with an ignored distractor are inhibited during prime selection or (2) a version of episodic retrieval theory in which the prime distractor and items associated with it are tagged as "to-be-ignored" during prime selection.     

Affective matching moderates S-R binding

We investigated the moderating influence of affective matching on S-R binding processes in a sequential priming study in which positive and negative nouns had to be categorised as referring to a person or to an object. Irrelevant positive and negative distractor words (adjectives) were integrated with responses into S-R episodes if they had the same valence as the target (affective match condition). In this case, repeating the prime distractor in the probe led to a retrieval of the prime response, which facilitated performance for response repetition sequences but had no effect on performance when responses changed between prime and probe. However, if target and distractor had different valences (affective mismatch condition), no interaction of distractor relation and response relation occurred, indicating that distractors were less likely to be associated with responses into event files during the prime trial episode. Findings reveal that affective mismatches are detected automatically and modulate a binding of irrelevant information with responses.     

Affective matching moderates S–R binding

We investigated the moderating influence of affective matching on S–R binding processes in a sequential priming study in which positive and negative nouns had to be categorised as referring to a person or to an object. Irrelevant positive and negative distractor words (adjectives) were integrated with responses into S–R episodes if they had the same valence as the target (affective match condition). In this case, repeating the prime distractor in the probe led to a retrieval of the prime response, which facilitated performance for response repetition sequences but had no effect on performance when responses changed between prime and probe. However, if target and distractor had different valences (affective mismatch condition), no interaction of distractor relation and response relation occurred, indicating that distractors were less likely to be associated with responses into event files during the prime trial episode. Findings reveal that affective mismatches are detected automatically and modulate a binding of irrelevant information with responses.     

The use of abstract graphemic information in lexical access

Three experiments investigated the nature of the information required for the lexical access of visual words. A four-field masking procedure was used, in which the presentation of consecutive prime and target letter strings was preceded and followed by presentations of a pattern mask. This procedure prevented subjects from identifying, and thus intentionally using, prime information. Experiment I extablished the existence of a semantic priming effect on target identification, demonstrating the lexical access of primes under these conditions. It also showed a word repetition effect independent of letter case. Experiment II tested whether this repetition effect was due to the activation of graphemic or phonemic information. The graphemic and phonemic similarity of primes and targets was varied. No evidence for phonemic priming was found, although a graphemic priming effect, independent of the physical similarity of the stimuli, was obtained. Finally Experiment III demonstrated that, irrespective of whether the prime was a word or a nonword, graphemic priming was equally effective. In both Experiments II and III, however, the word repetition effect was stronger than the graphemic priming effect. It is argued that facilitation from graphemic priming was due to the prime activating a target representation coded for abstract (non-visual) graphemic features, such as letter identities. The extra facilitation from same identity priming was attributed to semantic as well as graphemic activation. The implications of these results for models of word recognition are discussed.     

Affective priming with pictures of emotional scenes: the role of perceptual similarity and category relatedness

Prime pictures portraying pleasant or unpleasant scenes were briefly presented (150-ms display; SOAs of 300 or 800 ms), followed by probe pictures either congruent or incongruent in emotional valence. In an evaluative decision task, participants responded whether the probe was emotionally positive or negative. Affective priming was reflected in shorter response latencies for congruent than for incongruent prime-probe pairs. Although this effect was enhanced by perceptual similarity between the prime and the probe, it also occurred for probes that were physically different, and the effect generalized across semantic categories (animals vs. people). It is concluded that affective priming is a genuine phenomenon, in that it occurs as a function of stimulus emotional content, in the absence of both perceptual similarity and semantic category relatedness between the prime and the probe.