Where has all the inhibition gone? Insights from electrophysiological measures into negative priming without probe distractors

Responses to probe targets that have been distractors in a prime display are slower than responses to unrepeated stimuli, a finding labeled negative priming (NP). However, without probe distractors the NP effect usually diminishes. The present study is the first to investigate ERP correlates of NP without probe distractors to shed light on the processes underlying NP. Based on existing findings in the field, we analyzed two ERP correlates that have been associated with the visual NP effect so far, namely the N200 and the P300. As expected, no behavioral NP effect as well as no N200 modulation emerged. However, the P300 component was enhanced when a prime distractor was repeated as the probe target. This effect is interpreted as reflecting automatic retrieval of the prime episode occurring independently of the presence of probe distractors.     

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.     

Increased perceptual and conceptual processing difficulty makes the immeasurable measurable: negative priming in the absence of probe distractors

Negative priming (NP) refers to the finding that people's responses to probe targets previously presented as prime distractors are usually slower and more error prone than to unrepeated stimuli. In a typical NP experiment, each probe target is accompanied by a distractor. It is an accepted, albeit puzzling, finding that the NP effect depends on the presence of these probe distractors; for, without probe distractors, NP diminishes. This phenomenon causes severe problems for the majority of theoretical accounts of NP. In the present study, we follow a simple argument, namely that without probe distractors, the difficulty of responding to the probe is so low that NP becomes irrelevant. Hence, by increasing perceptual processing difficulty, as well as by increasing conceptual processing difficulty, significant NP effects with constantly absent probe distractors can be reliably observed. In addition, our results also show that NP without probe distractors can be found by exclusively manipulating probe display processing. This finding furthers our understanding of the processes causing NP.     

启动刺激含有多个靶子条件下的负启动效应

采用数字命名任务,在通常的负启动范式基础上增加启动刺激靶子数目．进行了两个实验。实验一发现,当启动刺激靶子个数为1个和2个时。出现负启动效应;当启动刺激靶子个数为3个和4个时。则不出现负启动效应。这提示靶子所获注意资源数量的作用。实验二发现．当启动刺激有2个和3个靶子时．如果未被选择来反应的靶子成为探测刺激的靶子,其反应时与控制组无显著差异。即不出现负启动。这表明在启动刺激中未被选择来反应的靶子与干扰项所受到的加工是有差别的。     

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.     

Attention capture by contour onsets and offsets: No special role for onsets

In five experiments, we investigated the power of targets defined by the onset or offset of one of an object’s parts (contour onsets and offsets) either to guide or to capture visual attention. In Experiment 1, search for a single contour onset target was compared with search for a single contour offset target against a static background of distractors; no difference was found between the efficiency with which each could be detected. In Experiment 2, onsets and offsets were compared for automatic attention capture, when both occurred simultaneously. Unlike in previous studies, the effects of overall luminance change, new-object creation, and number of onset and offset items were controlled. It was found that contour onset and offset items captured attention equally well. However, display size effects on both target types were also apparent. Such effects may have been due to competition for selection between multiple onset and offset stimuli. In Experiments 3 and 4, single onset and offset stimuli were presented simultaneously and pitted directly against one another among a background of static distractors. In Experiment 3, we examined “guided search,” for a target that was formed either from an onset or from an offset among static items. In Experiment 4, the onsets and offsets were uncorrelated with the target location. Similar results occurred in both experiments: target onsets and offsets were detected more efficiently than static stimuli which needed serial search; there remained effects of display size on performance; but there was still no advantage for onsets. In Experiment 5, we examined automatic attention capture by single onset and offset stimuli presented individually among static distractors. Again, there was no advantage for onset over offset targets and a display size effect was also present. These results suggest that, both in isolation and in competition, onsets that do not form new objects neither guide nor gain automatic attention more efficiently than offsets. In addition, in contrast to previous studies in which onsets formed new objects, contour onsets and offsets did not reliably capture attention automatically.     

Negative priming with numbers: No evidence for a semantic locus

Selective attention has been studied extensively using the negative priming (NP) paradigm. An important issue regards the representational level at which NP occurs. We investigated this issue by using numbers as stimuli. Because numbers have a well-defined semantic organization, which can be clearly measured by means of the distance effect, they are very suitable for testing the assumption that NP is situated at a central semantic level. Four experiments are presented in which the numerical distance between prime distractor and probe target was manipulated. The task was magnitude comparison. Target and distractor were defined on the basis of colour. In Experiment 1, all numbers were presented in Arabic format; NP was observed only with identical prime distractor and probe target, and no distance-related NP was observed. This could not be explained by a decay of inhibition since in Experiment 2 similar results were obtained with a shortened response-to-stimulus interval. Experiment 3 showed that these observations also hold for numbers presented verbally. Nevertheless, a cross-notational experiment with Arabic prime and verbal probe (Experiment 4) revealed no NP whatsoever and excluded the possibility that the absence of distance-related negative priming was the result of a fine-tuned inhibitory mechanism operating at the semantic level. The results are considered in the light of current theories of negative priming.     

Effects of perceptual grouping on positive and negative priming

The effects of perceptual grouping/segregation of targets and distractors by means of colour on positive and negative priming were examined in two experiments. In Experiments 1 and 2 we examined whether grouping of target and distractors by means of common colour in the prime display affected positive and negative priming, or whether these effects depend on prime–probe contextual similarity in colour. In addition, we examined the effects of the predictability of target colour in the prime and the probe displays across the experiments using mixed (Experiment 1) or blocked procedures (Experiment 2). The pattern of results was similar in both experiments, indicating that the positive priming effect was determined by target repetition and enhanced by perceptual segregation of target from distractors in the prime display. The negative priming effect was determined by grouping the target and distractors by common colour in the prime display. The results of the present experiments are consistent with inhibition-based models of negative priming.     

Early activity in the lateralized readiness potential suggests prime-response retrieval as a source of negative priming

Negative priming (NP) refers to increased response time (RT) for a probe target that was a distractor in a preceding prime presentation (distractor-target shift, DT), compared to novel targets. The present study used the lateralized readiness potential (LRP) to investigate, in a four-choice identification task, a novel episodic-retrieval explanation of NP introduced by Rothermund, Wentura, and de Houwer (2005). This theory proposes that retrieval reactivates the prime response which interferes with selection of the correct probe response, thereby producing NP. 20 participants responded to pairs of red and blue digits, contingent on the identity of the digit presented in the target color. Behavioral NP involved RT increase by 16 ms. With shift trials (different hands used for prime and probe responses), in the DT condition LRP onset was delayed relative to control. By contrast, earlier LRP onset was observed for DT relative to control with no-shift trials (same hand used for prime and probe responses). Behavioral NP effects showed similar magnitude for shift and no-shift trials. Results support the Rothermund et al. (2005) theory of prime-response retrieval.     

Negative priming in a gender decision task and in a semantic categorization task

In three experiments, we tested the hypothesis that negative priming (NP) can occur without prime or target selection, when conflicting properties are associated with the prime and the target, and when the experimental conditions allow the encoding of the target as a separate episode from the prime. These predictions were confirmed in Experiment 1, using a gender decision task. Responses were slower when prime and target had the same gender than when they had different genders, with an inter-stimulus interval (ISI) of 600 ms but not with an ISI of 25 ms. Experiment 2 eliminated a possible explanation of the NP obtained in Experiment 1, in terms of response inhibition during the prime processing. Finally, Experiment 3 demonstrated the replicability and the generality of our NP, in a semantic categorization task. Empirical and theoretical consequences of our results for studies using the priming paradigm are discussed.     

Subliminal access to abstract face representations does not rely on attention

The present study used masked repetition priming to examine whether face representations can be accessed without attention. Two experiments using a face recognition task (fame judgement) presented masked repetition and control primes in spatially unattended locations prior to target onset. Experiment 1 (n=20) used the same images as primes and as targets and Experiment 2 (n=17) used different images of the same individual as primes and targets. Repetition priming was observed across both experiments regardless of whether spatial attention was cued to the location of the prime. Priming occurred for both famous and non-famous targets in Experiment 1 but was only reliable for famous targets in Experiment 2, suggesting that priming in Experiment 1 indexed access to view-specific representations whereas priming in Experiment 2 indexed access to view-invariant, abstract representations. Overall, the results indicate that subliminal access to abstract face representations does not rely on attention.     

Load theory of selective attention and the role of perceptual load: Is it time for revision?

Perceptual load hypothesis is proposed as a compromise between early and late theory of selective attention which states that the selection will operate early when the load on perception is high and it will operate late when the load on perception is low. Experimental findings have shown that the perceptual load hypothesis is too simplistic in nature as perceptual load is not the only determinant of selection processes. It is difficult to apply the load hypothesis to explain the occurrence of early selection in low load displays as well as the selection processes that operate on distractor and target stimuli that are a part of the same object. Factors like spatial proximity, cues that manipulate the spatial extent of attentional focus, salience of targets as well as the distractors, and perceptual grouping between the target and the distractors should be taken into account while explaining the selective control of attention. Thus, the perceptual load of the display is one such factor that affects selective attention and goal-directed behaviour, but it is not the only factor to affect the selective control of attention.     

跨通道语义启动对视觉注意的影响

采用生活中的真实客体,我们考察了跨通道语义相关性对视觉注意的影响以及跨通道促进的时程。结合启动范式和点探测范式,实验1发现在听觉启动600毫秒后,被试对高相关视觉刺激的反应比对低相关刺激的反应更快,而在视觉启动下没有发现启动效应。实验2发现在启动刺激呈现900毫秒后跨通道启动效应消失。我们的研究证明了基于先前经验的视、听语义相关能够促进视觉的选择性注意。     

Localized attentional interference affects object individuation, not feature detection

Modern theorists conceptualize visual selective attention as a competition between object representations for the control of extrastriate receptive fields, an account supported by the finding that attentional selection of one stimulus can degrade processing of nearby stimuli. In the present study the conditions that produce reciprocal interference between attended stimuli are examined. Each display contained either no, one, or two feature-defined target items among an array of homogeneous distractors. Observers performed two tasks, feature detection and object individuation. The feature-detection task required observers to determine if any targets were present within the display. The object-individuation task required observers to determine if the number of targets was exactly two. Spatially mediated interference between target pairs occurred in the object-individuation task, but had no effect on feature detection. Results suggest that localized interference between attended stimuli occurs only when observers are required to resolve the features of individual objects, consistent with the competitive interaction models of attention.     

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.     

Identity and semantic negative priming in rapid serial visual presentation streams

In selective attention tasks, the efficiency of processing concurrently presented target and distractor stimuli in a given display is often influenced by the relationship these stimuli have with those in the previous display. When a to-be-attended target on a current trial (the probe trial) matches the ignored, non-target distractor on a previous trial (the prime trial), a response to the target is typically delayed compared with when the two stimuli are not associated. This negative priming (NP) phenomenon has been observed in numerous studies with traditional NP tasks presenting the target and distractor simultaneously in both the prime and probe trial couplets. Here, however, in four experiments using a mixture of stimulus types (letters, digits, English number words, and logographic Chinese number words), target and distractor stimuli were temporally separated in two rapid serial visual presentation (RSVP) streams instead of concurrently presented. The findings provide a conceptual replication and substantial extension of a recent study by Wong (Plos One, 7, e37023, 2012), and suggest that active suppression of irrelevant distracting information is a more ubiquitous form of cognitive control than previously thought.     

The negative priming effect: Inhibitory priming by ignored objects

A priming paradigm was employed to investigate the processing of an ignored object during selection of an attended object. Two issues were investigated: the level of internal representation achieved for the ignored object, and the subsequent fate of this representation. In Experiment 1 a prime display containing two superimposed objects was briefly presented. One second later a probe display was presented containing an object to be named. If the ignored object in the prime display was the same as the subsequent probe, naming latencies were impaired. This effect is termed negative priming. It suggests that internal representations of the ignored object may become associated with inhibition during selection. Thus, selection of a subsequent probe object requiring these inhibited representations is delayed. Experiment 2 replicated the negative priming effect with a shorter inter-stimulus interval. Experiment 3 examined the priming effects of both the ignored and the selected objects. The effect of both identity repetition and a categorical relationship between prime and probe stimuli were investigated. The data showed that for a stimulus selected from the prime display, naming of the same object in the probe display was facilitated. When the same stimulus was ignored in the prime display, however, naming of it in the probe display was again impaired (negative priming). That negative priming was also demonstrated with categorically related objects suggests that ignored objects achieve categorical levels of representation, and that the inhibition may be at this level.     

Global/local processing and negative priming: the influence of selection difficulty and stimulus exposure

Negative priming is a decrement in performance observed when a previously ignored stimulus is re-presented as a target. The present study examined the relation between selection difficulty and negative priming in five experiments that used hierarchical stimuli (large letters made up by small letters). The results show that negative priming is greater when subjects direct attention to the local level (more difficult selection) than when they direct attention to the global level (less difficult selection). However, that occurs only when exposure of prime and probe is sufficiently long. With shorter presentations, negative priming is still observed but is no longer modulated by selection difficulty. These results suggest that both anticipatory and reactive mechanisms are responsible for the occurrence of negative priming and that instantiation of the reactive mechanism depends on the time available for prime and probe selection. Received: 17 January 2000 / Accepted: 3 July 2000     

Eye movements as a gatekeeper for memorization: evidence for the persistence of attentional sets in visual memory search

Attention is known to serve multiple goals, including the selection of information for further perceptual analysis (selection for perception) and for goal-directed behavior (selection for action). Here, we study the role of overt attention (i.e., eye movements) as a gatekeeper for memorization processes (selection for memorization). Subjects memorized complex multidimensional stimulus displays and subsequently indicated whether a specific (probe) item was present. In Experiment 1 we utilized an incidental learning setting where in the beginning only a subset of display stimuli was relevant, whereas in a transfer block all stimuli were possible probe items. In Experiment 2, we used an explicit learning setting within a between-group design. Response times and gaze patterns indicated that subjects learned to ignore irrelevant stimuli while forming memory representations. The findings suggest that complex feature binding processes in peripheral vision may serve to guide overt selective attention, which eventually contributes to filtering out irrelevant information even in highly complex environments. Gaze patterns suggested that attentional control settings persisted even when they were no longer required.     

Negative priming from ignored distractors in visual selection: A review

Ignoring a distractor on a prime trial generally impairs responses to that object on a subsequent probe trial. This negative-priming (NP) effect supports the notion that distracting objects are actively inhibited during target selection (Tipper, 1985). Alternatively, NP may be caused either by amismatch between the features of items across prime and probe trials (Park & Kanwisher, 1994) or by the episodic retrieval of information from the prime trial which conflicts with the current, correct response (Neill & Valdes, 1992). These alternative accounts are called theselective inhibition,feature mismatching, andepisodic retrieval hypotheses, respectively. The present paper reviews the NP literature and considers the evidence for each of the three accounts. Feature mismatching does produce NP in a limited number of cases, but it is not a necessary condition for NP. In other cases, NP must be due to either selective inhibition or episodic retrieval of previously ignored distractors. Though results from critical tests designed to discriminate among these hypotheses have not yet been reported, such results are crucial for both theoretical and practical reasons.