Strategy effects counteract distractor inhibition: negative priming with constantly absent probe distractors

It is an accepted, albeit puzzling finding that negative priming (NP) hinges on the presence of distractors in probe displays. In three experiments without probe distractors, the authors yielded evidence that response-biasing processes based on the contingency between prime and probe displays may have caused this finding. It is argued that it is of help in standard NP experiments to process the distractor in the prime display in order to prepare the response to the probe target. When this contingency was removed (Experiments 2 and 3), NP was reliably observed without probe distractors, whereas no NP emerged if the design contained the typical contingency (Experiment 1). For this reason, the data suggest that the absence of NP, which is usually observed under these conditions, may be due to a contingency-based component.     

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.     

The effect of unconscious priming on temporal production

We examined the effects of unconscious priming on temporal-interval production. In Experiment 1, participants were instructed to keep visual displays on a screen for 2500 ms intervals. Half of the displays were repeated across blocks throughout the entire experiment, and the others were newly generated from trial to trial. The displays consisted of patterns so complex that the participants could not intentionally memorize them. The results showed that significantly more time elapsed for old displays than for new displays before participants indicated that a 2500 ms interval had elapsed. Experiment 2 replicated this effect and excluded an alternative account based on perceived pattern complexity. The effect of repetitive presentation was obtained despite the fact the participants did not recognize the repetition, suggesting that unconscious priming increased temporal production. These results suggest that time perception is affected by an unconscious process.     

Children do show negative priming: further evidence for early development of an intact selective control mechanism

Reactions to stimuli that were shortly before presented as distractors are usually slowed down; this phenomenon is known as negative priming. Negative priming is an accepted index for tapping into selective control mechanisms. Although this effect is well established for adults, it has been claimed that children do not show negative priming. Recently, however, V. E. Pritchard and E. Neumann challenged this view and concluded that selective control mechanisms are already fully developed in young children. The authors of the present study analyzed differences between older studies, in which no negative priming had been observed, and the Pritchard and Neumann (2004) study. In sum, the present study yielded further evidence for an intact selective control mechanism in young children. The authors also linked this empirical finding to the broader literature on negative priming by a direct comparison with an adult sample.     

Letter search does not affect semantic priming in a probe naming task

The normally robust semantic priming effect observed in lexical decision is usually reduced to the point of being absent, when a letter search has to be performed on the prime. It has been argued that semantic activation is thus not an automatic process but rather cognitively controlled and therefore adaptable to task demands. We examined the effects of letter search priming on pronunciation times and found a reliable semantic priming effect, following letter search that was not affected at all relative to a standard condition, where participants silently read the prime. Thus the nature of the prime task did not seem to affect the processing mode employed, semantic access occurred even though attention was focused on surface properties of the prime.     

Effect of stimulus repetition on positive and negative identity priming

Most negative-priming experiments have used a limited number of stimuli that are repeated many times throughout the experiment. We report five experiments that examine in greater detail the role of stimulus repetition in negative priming. Subjects were presented with displays consisting of two or more words, and were required to name the word printed in red. On attended repetition (AR) trials, the target word was the same as the target word on the preceding trial. On ignored repetition (IR) trials, the target word was the same as the distractor word on the preceding trial. Experiments 1 and 2 used novel words, and obtained positive priming on AR trials, but no negative priming on IR trials. Experiments 3 and 4 used repeated words, and obtained negative priming on IR trials, but no positive priming on AR trials. In Experiment 5, both novel and repeated words were intermixed, and negative priming was observed for repeated, but not novel, IR conditions, whereas positive priming was observed for novel, but not repeated, AR conditions. Together, Experiments 1–5 demonstrate that positive and negative identity priming are modulated by stimulus repetition and are stimulus specific.     

A challenging dissociation in masked identity priming with the lexical decision task

The masked priming technique has been used extensively to explore the early stages of visual-word recognition. One key phenomenon in masked priming lexical decision is that identity priming is robust for words, whereas it is small/unreliable for nonwords. This dissociation has usually been explained on the basis that masked priming effects are lexical in nature, and hence there should not be an identity prime facilitation for nonwords. We present two experiments whose results are at odds with the assumption made by models that postulate that identity priming is purely lexical, and also challenge the assumption that word and nonword responses are based on the same information. Our experiments revealed that for nonwords, but not for words, matched-case identity PRIME–TARGET pairs were responded to faster than mismatched-case identity prime–TARGET pairs, and this phenomenon was not modulated by the lowercase/uppercase feature similarity of the stimuli.     

The boundary conditions of priming of visual search: From passive viewing through task-relevant working memory load

Priming of visual search has a dominating effect upon attentional shifts and is thought to play a decisive role in visual stability. Despite this importance, the nature of the memory underlying priming remains controversial. To understand more fully the necessary conditions for priming, we contrasted passive versus active viewing of visual search arrays. There was no priming from passive viewing of search arrays, while it was strong for active search of the same displays. Displays requiring no search resulted in no priming, again showing that search is needed for priming to occur. Finally, we introduced working memory load during visual search in an effort to disrupt priming. The memorized items had either the same colors as or different colors from the visual search items. Retaining items in working memory inhibited priming of the working memory task-relevant colors, while little interference was observed for unrelated colors. The picture that emerges of priming is that it requires active attentional processing of the search items in addition to the operation of visual working memory, where the task relevance of the working memory load plays a key role.     

Response-bound primes diminish affective priming in the naming task

We found affective priming in the naming task (i.e., faster naming of a target picture that follows a valence-congruent prime picture compared to an incongruent prime) significantly reduced if prime stimuli were strongly bound to a naming response compared to when primes did not elicit a naming response. This result indicates that affective priming in the naming task originates from encoding facilitation processes, which are usually overshadowed by response conflict due to primes that also trigger a naming response.     

The locus of semantic priming effects in person recognition

Semantic priming in person recognition has been studied extensively. In a typical experiment, participants are asked to make a familiarity decision to target items that have been immediately preceded by related or unrelated primes. Facilitation is usually observed from related primes, and this priming is equivalent across stimulus domains (i.e., faces and names prime one another equally). Structural models of face recognition (e.g., IAC: Burton, Bruce, & Johnston, 1990) accommodate these effects by proposing a level of person identity nodes (PINs) at which recognition routes converge, and which allow access to a common pool of semantics. We present three experiments that examine semantic priming for different decisions. Priming for a semantic decision (e.g., British/American?) shows exactly the same pattern that is normally observed for a familiarity decision. The pattern is equivalent for name and face recognition. However, no semantic priming is observed when participants are asked to make a sex decision. These results constrain future models of face processing and are discussed with reference to current theories of semantic priming.     

Selective attention and search images in pigeons

In a visual search task, pigeons detected targets when pretrial visual cues or blocked trial sequences signaled the target's identity. Sequential priming was robust over a wide range of intertrial intervals, but visual priming was unstable when the delay between cue offset and display onset was varied. Larger target set sizes enhanced sequential, but not visual, priming. Sequential priming did not depend on display size over the range of relatively large displays used. However, ambiguously cued targets in small displays were detected more quickly than primed targets in large displays. These findings suggest that naturalistic selection biases, or "search images," may be attributable to sequential priming and that the common attentional mechanism has moderately selective properties.     

语义启动模型以及启动范围

启动效应一般分为两种——知觉启动和语义启动(概念启动)。语义启动的范式逐渐成为研究语义知识在大脑中是如何存储的主要研究手段。该文针对语义启动发生的3种机制:激活扩散模型,复合线索模型和分布式记忆模型进行了简要的评述,并且重点介绍了分布式记忆模型。同时对启动效应可以激活语义知识的范围作了一个简要的概括。     

Negative priming is stronger for task-relevant dimensions: Evidence of flexibility in the selective ignoring of distractor information

The finding that in selective attention tasks responses to previously ignored stimuli are usually retarded is known as negative priming (NP). In previous studies it has been suggested that NP can depend on behavioural goals—that is, NP was observed only for task-relevant object dimensions. We extend these findings with two experiments demonstrating that stronger NP can be observed for task-relevant dimensions than for task-irrelevant dimensions (a) even if participants' tasks vary blockwise within an experiment and (b) if behavioural goals vary from trial to trial. These results suggest that selective NP is a much more flexible process than previously assumed.     

Negative priming is stronger for task-relevant dimensions: Evidence of flexibility in the selective ignoring of distractor information

The finding that in selective attention tasks responses to previously ignored stimuli are usually retarded is known as negative priming (NP). In previous studies it has been suggested that NP can depend on behavioural goals—that is, NP was observed only for task-relevant object dimensions. We extend these findings with two experiments demonstrating that stronger NP can be observed for task-relevant dimensions than for task-irrelevant dimensions (a) even if participants' tasks vary blockwise within an experiment and (b) if behavioural goals vary from trial to trial. These results suggest that selective NP is a much more flexible process than previously assumed.     

Sequential priming of 3-D perceptual organization

In four experiments, the effects of sequential priming on the perceptual organization of complex three-dimensional (3-D) displays were examined. Observers were asked to view stereoscopic arrays and to search an embedded subset of items for an odd-colored target while 3-D orientation of the stimuli was varied randomly between trials. Search times decreased reliably when 3-D stimulus orientation was unchanged on consecutive trials, indicating substantial sequential priming by 3-D stimulus layout. The priming was nonsensory and was independent of priming by additional stimulus characteristics. Finally, priming by 3-D layout was unaffected by observers' foreknowledge of display orientation. Results indicate that perceptual organization of 3-D stimuli is guided by a short-term trace of 3-D spatial relationships between stimuli.     

Unconscious masked priming depends on temporal attention

The cognitive processes at work in masked priming experiments are usually considered automatic and independent of attention. We provide evidence against this view. Three behavioral experiments demonstrate that the occurrence of unconscious priming in a number–comparison task is determined by the allocation of temporal attention to the time window during which the prime–target pair is presented. Both response–congruity priming and physical repetition priming vanish when temporal attention is focused away from this time window. These findings are inconsistent with the concept of a purely automatic spreading of activation during masked priming.     

Inhibitory stroke neighbour priming in character recognition and reading in Chinese

In alphabetic languages, prior exposure to a target word's orthographic neighbour influences word recognition in masked priming experiments and the process of word identification that occurs during normal reading. We investigated whether similar neighbour priming effects are observed in Chinese in 4 masked priming experiments (employing a forward mask and 33-ms, 50-ms, and 67-ms prime durations) and in an experiment that measured eye movements while reading. In these experiments, the stroke neighbour of a Chinese character was defined as any character that differed by the addition, deletion, or substitution of one or two strokes. Prime characters were either stroke neighbours or stroke non-neighbours of the target character, and each prime character had either a higher or a lower frequency of occurrence in the language than its corresponding target character. Frequency effects were observed in all experiments, demonstrating that the manipulation of character frequency was successful. In addition, a robust inhibitory priming effect was observed in response times for target characters in the masked priming experiments and in eye fixation durations for target characters in the reading experiment. This stroke neighbour priming was not modulated by the relative frequency of the prime and target characters. The present findings therefore provide a novel demonstration that inhibitory neighbour priming shown previously for alphabetic languages is also observed for nonalphabetic languages, and that neighbour priming (based on stroke overlap) occurs at the level of the character in Chinese.     

The costs and benefits of cross-task priming

Two lines of research on cross-task priming yield opposite results. Research on repetition priming observed positive priming, whereas research on the role of priming in task-switching observed negative effects. We combined the two types of design. In the transfer phase of our paradigm, subjects performed task B either as a pure block (BBB) or as a switch block (ABAB). We presented items which were either unprimed or primed by prior presentation during a preceding priming phase performed on task A. Amongst others, the priming effect is determined by two factors: First, the more operation time the system needs during the probe event, the higher the likelihood to obtain priming. Protracting operation time by reducing stimulus quality favors positive priming, whereas providing more operation time by making subjects switch between tasks favors negative priming. Second, the strength of the memory trace of the prime event determines whether that trace can possibly yield negative priming, in that only strong traces can be retrieved together with the associated task/response.     

Investigating a memory-based account of negative priming: support for selection-feature mismatch

Using typical and modified negative priming tasks, the selection-feature mismatch account of negative priming was tested. In the modified task, participants performed selections on the basis of a semantic feature (e.g., referent size). This procedure has been shown to enhance negative priming (P. A. MacDonald, S. Joordens, & K. N. Seergobin, 1999). Across 3 experiments, negative priming occurred only when the repeated item mismatched in terms of the feature used as the basis for selections. When the repeated item was congruent on the selection feature across the prime and probe displays, positive priming arose. This pattern of results appeared in both the ignored- and the attended-repetition conditions. Negative priming does not result from previously ignoring an item. These findings strongly support the selection-feature mismatch account of negative priming and refute both the distractor inhibition and the episodic-retrieval explanations.     

Interaction of prime and target in the subliminal affective priming effect

It has been found that an emotional stimulus such as a facial expression presented subliminally can affect subsequent information processing and behavior, usually by shifting evaluation of a subsequent stimulus to a valence congruent with the previous stimulus. This phenomenon is called subliminal affective priming. The present study was conducted to replicate and expand previous findings by investigating interaction of primes and targets in the affective priming effect. Two conditions were used. Prime (subliminal presentation 35 msec.) of an angry face of a woman and a No Prime control condition. Just after presentation of the prime, an ambiguous angry face or an emotionally neutral face was presented above the threshold of awareness (500 msec.). 12 female undergraduate women judged categories of facial expressions (Anger, Neutral, or Happiness) for the target faces. Analysis indicated that the Anger primes significantly facilitated judgment of anger for the ambiguous angry faces; however, the priming effect of the Anger primes was not observed for neutral faces. Consequently, the present finding suggested that a subliminal affective priming effect should be more prominent when affective valence of primes and targets is congruent.