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     

Inhibition Accompanies Reference-Frame Selection

Spatial relational terms are ambiguous because they can be defined by different and sometimes conflicting frames of reference. Previous research has suggested that multiple reference frames are simultaneously active before a reference frame is selected. Two experiments examined the on-line selection of a reference frame to determine whether it is assisted by inhibition. These experiments used a negative-priming paradigm in which access to a reference frame was assessed on trial n when that reference frame was either available but not selected or not available on trial n – 1. Significant negative priming was observed; it operated along the axis of the reference frame, encompassing both endpoints. In addition, reference-frame selection seems to be independent of object selection. We cast these findings within the view of negative priming as an inhibitory mechanism, and discuss their implications for the use of spatial relations.     

Selection and inhibition in infancy: evidence from the spatial negative priming paradigm

We used a spatial negative priming (SNP) paradigm to examine visual selective attention in infants and adults using eye movements as the motor selection measure. In SNP, when a previously ignored location becomes the target to be selected, responses to it are impaired, providing a measure of inhibitory selection. Each trial consisted of a prime and a probe, separated by 67, 200, or 550 ms interstimulus intervals (ISIs). In the prime, a target was accompanied by a distractor. In the probe, the target appeared either in the location formerly occupied by the distractor (ignored repetition) or in another location (control). Adults exhibited the SNP effect in all three ISI conditions, producing slower saccade latencies on ignored repetition versus control trials. The SNP effect obtained for infants only under 550 and 200 ms ISI conditions. These results suggest that important developments in visual selection are rooted in emerging inhibitory mechanisms.     

Negative priming between pictures and words in a selective attention task: Evidence for semantic processing of ignored stimuli

This study examined the processing of ignored pictures and words when attention was directed to a different picture or word. Previous work by Tipper (1985) demonstrated that the priming effect of an ignored picture on a subsequent categorically related picture is inhibitory. This effect was termednegative priming. Tipper concluded that ignored pictures achieved abstract categorical levels of internal representation, and that these representations were inhibited during selection of a simultaneously presented picture. This conclusion, however, was premature. Observation of the figures used by Tipper suggests that objects within a category have greater structural similarity than do objects in different categories. The negative priming effect could therefore be at a structural level of representation. The present study examined priming across symbolic domains (pictures and words) where there was no structural relationship between objects. Negative priming was again observed and was equivalent to the negative priming observed within symbolic domain. These data suggest that ignored drawings and words do achieve abstract categorical levels of representation, and that the mechanisms underlying negative priming operate at, or beyond, this level.     

Spatial stimulus-response compatibility and negative priming

According to Kornblum's (1992) dimensional overlap model, when an incongruent response to a stimulus is required, automatic activation of the congruent response must first be inhibited. Shiu and Kornblum (1996a) provided evidence for such inhibition in an incongruent symbolic negative priming task. Reaction time was longer when a trial's correct response was the name of the stimulus from the previous trial than when it was not. We report three experiments that test this inhibition hypothesis for spatial stimuli and responses. In Experiment 1, which used a spatial mapping analogous to the symbolic mapping used by Shiu and Kornblum (1996a), a similar negative priming effect was found. However, in Experiments 2 and 3, which used mappings that were conducive to simple transformational rules, a positive priming effect was obtained. The results suggest that inhibition in response selection may depend on the complexity of the relations between the stimuli and responses.     

Target selection difficulty, negative priming, and aging

It has been recently suggested that the presence of identity negative priming effects in old adults could occur when there is substantial processing of the distracting information in a selective attention task (J. M. Kieley & A. A. Hartley, 1997). In three experiments, using a letter identification task, it was found that making target selection more difficult increased the magnitude of the negative priming effect to a similar extent in both young and old adults. Moreover, the size of the negative priming effect did not differ between young and elderly participants. These results are discussed with respect to the issue of age-related deficits in the mechanisms underlying negative priming.     

Influence of mapping complexity on negative priming for incompatible spatial mappings

For tasks with an incompatible stimulus-response mapping, whether the compatible response must be inhibited paradigm for four-choice tasks with three different incompatible spatial mappings. For a mapping that did not follow a simple rule, reaction time was lengthened when the corresponding response on the preceding trial became the required response on the current trial, as compared with when it did not, showing a negative priming effect. However, for mappings that followed a simple rule, negative priming was not evident. The present study extends this research to a more complex mapping. On the basis of a two-process model adopted from the negative priming literature, we hypothesized that high mapping complexity should also diminish the negative priming effect for incompatible mappings, because the balance of cognitive resources is allocated to identification of the correct response. Two experiments are reported in which mappings of different complexity were used in six-choice spatial tasks. Analyses of reaction times showed that negative priming diminished with increased mapping complexity, apparently due to increased dominance of response identification processes, rather than inhibition of the corresponding response.     

The control of visual attention and its influence on prioritized processing in a location negative priming paradigm

In a location-based negative priming paradigm, the possibility of a disengagement option of the underlying inhibitory mechanism was tested. Whereas in previous studies disengagement was observed when providing utility information about the probe trial structure, in the present study the allocation of visual attention to the stimuli was manipulated. In the first step an automatic deployment of visual attention was implemented by presenting all stimuli as abrupt onsets (Experiment 1), which demonstrated commonly observed negative priming effects. In further conditions of non-automatic allocation of visual attention in which target and distractor were presented as no-onset stimuli, negative priming effects were eliminated (Experiments 2 and 3). The preferred interpretation is that in conditions of automatic control of attention, target and distractor compete for control of action. A non-automatic control of visual attention, on the other hand, leads to a top-down modulated selection, which results in prioritized target encoding and a loss of distractor impact on the selection process. Alternative accounts and the role of no-onset distractor processing were investigated in Experiment 4.     

Stem homographs and lemma level representations

Previous studies have found that priming a target like cerr-o ("hill") with an unmasked stem-homograph (e.g., cerr-ar, "to close") or with an unmasked allomorph of a stem-homograph (e.g., cierr-a, "he/she/it closes") has an inhibitory effect on target recognition. We report evidence from stem-homograph priming studies that implicate both morphological parsing and lexical selection processes at the lemma level. We argue that stem-homograph inhibition is the product of lexical selection mechanisms that are engaged just when a fully ambiguous stimulus (here, an inflectional stem) must be assigned one of its viable interpretations in order to afford conscious perception of lexical identity.     

A critical evaluation of cognitive inhibition in dissociative identity disorder as inferred by negative priming in the flanker task: Limitations and the episodic retrieval alternative

Studies examining negative priming in dissociative identity disorder (DID) using the flanker task have reported emotional context effects. Significant negative priming is evident when individuals with DID are assessed in a context deemed emotionally neutral, while in contexts designed to elevate anxiety, DID samples display reduced negative priming. Limitations and considerations are discussed around statistical power, generalizability and reliability, and the use of diagnostic groups over specific clinical symptoms. The negative priming findings in this growing body of work have been interpreted with reference to the functioning of cognitive inhibitory mechanisms. Explored is how the episodic retrieval account of negative priming, with its reliance on memory mechanisms, could account for the DID findings. Encoding and retrieval possibilities are discussed and it is concluded that a failure to encode the prime trial distractor stimulus, in contexts of heightened anxiety, could explain the experimental findings from an episodic retrieval perspective.     

Does negative priming reflect inhibitory mechanisms? A review and integration of conflicting views

Negative priming has traditionally been viewed as a reflection of an inhibitory mechanism of attention. However, recent accounts have suggested that negative priming does not reflect inhibitory mechanisms. Rather, slowed reaction times on negative priming trials are either due to retrieval of incompatible response tags or of mismatching perceptual information, or due to extra processes needed to distinguish past from present information. In contrast, it is proposed that there is no firm evidence to discount inhibition models. In fact, although retrieval processes can be implicated in negative priming effects, understanding of these requires consideration of the inhibitory processes involved in selecting information for goal-directed behaviour.     

Attentional demand and memory retrieval in negative priming

Negative priming refers to delayed response to previous distractors, and can reflect the operation of attentional selection in prime trials. One important feature of negative priming is that it is modulated by the characteristics of probe trials. The current study manipulated competition from probe distractors and prime-probe similarity to examine the effects of attentional demand and memory retrieval in probe trials. The results demonstrated that the effects of attentional demand and memory retrieval on negative priming were dynamic. Distractor competition in probe trials affected negative priming in Experiment 1, and prime-probe similarity affected negative priming in Experiment 2. Moreover, negative priming in Experiment 3 was observed either when competition from probe distractors was strong or when identical spatial layouts were used in prime-probe couplets. Taken together, either competition from probe distractors or prime-probe similarity of spatial layouts was critical to the manifestation of negative priming at one time. Implications for distractor inhibition and memory retrieval in negative priming were discussed.     

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.     

Spatial frequency and attention: Effects of level-, target-, and location-repetition on the processing of global and local forms

Is attentional selection between local and global forms based on spatial frequency? This question was examined by having subjects identify local or global forms of stimuli that had been “contrast balanced,” a technique that eliminates low spatial frequencies. Response times (RTs) to global (but not local) forms were slowed for contrast-balanced stimuli, suggesting that low spatial frequencies mediate the global RT advantage typically reported. In contrast, the beneficial effect of having targets appear at the same, as opposed to a different, level as that on the immediately preceding trial was unaffected by contrast balancing. This suggests that attentional selection between different levels of structure is not based on spatial frequency. The data favor an explanation in terms of “priming,” rather than in terms of adjustments in the diameter of an attentional “spotlight.”     

Superior modulation of activation levels of stimulus representations does not underlie superior discrimination in autism

The performance of children with and without autism was compared in object-based positive and negative priming tasks within a visual search procedure. Object-based positive and negative priming effects were found in both groups of children. This result provides the first evidence for the activation of object-based representations during visual search task performance and further supports the notion that both excitatory and inhibitory guidance mechanisms are involved in target location in visual search. The children with autism were overall better than the typically developing children at visual search, thus replicating demonstrations of superior discrimination in autism. Furthermore, there was no difference between the magnitude of the positive nor the negative priming effects of the groups. This finding suggests that excitatory and inhibitory control operate comparably in autism and normal development. These results are discussed in the light of the superior ability of individuals with autism to discriminate between items. More specifically, it is argued that superior discrimination in autism does not result from enhanced top-down excitatory and inhibitory control.     

Antagonistic modulatory influences of negative affect on cognitive control: Reduced and enhanced interference resolution capability after the induction of fear and sadness

The present behavioral study investigated the influence of negative affect on the neural mechanisms of cognitive control. We expected to find evidence for an antagonistic modulation of cognition by threat-relevant and threat-irrelevant negative affect (i.e. fear and sadness) that should promote bottom-up monitoring and top-down selection, respectively. Subjects performed one of three conflict tasks (Stroop, Flanker, or Simon) that tap distinct control mechanisms of conflict resolution, comprising specific attentional and motor control processes. On each task trial, target stimuli were preceded by a face stimulus exhibiting a fearful, sad, or neutral expression, providing three affect conditions. Our data provides strong evidence for substantially increased selection (attentional and motor selection) after priming of threat-irrelevant negative affect (sadness). Deviating from the results of previous studies, our analysis did not consistently yield increased monitoring after fear priming. We discuss these findings with respect to the effectiveness of different experimental affect priming procedures (i.e. stimuli) and the role of the task context, among others.     

Influence of attended repetition trials on negative priming in younger and older adults

A lengthened response time when a distractor becomes a target, called negative priming, is an undisputed phenomenon in selective attention, yet just what the underlying mechanism responsible for negative priming is has not been resolved. In this study, the proportion of attended repetition trials was manipulated in order to test the predictions of three theories that have been proposed for explaining spatial negative priming: distractor suppression (e.g., Tipper, 1985), episodic memory retrieval (e.g., Neill, Valdes, &; Terry, 1995), and novelty bias (e.g., Milliken, Tipper, Houghton, &; Lupiáñez, 2000). The results supported the proposal that a novelty bias, which is flexible and can be overridden, is the primary mechanism responsible for priming in spatial tasks. Memory retrieval obscured the novelty bias for target processing, was more selective in older adults, and did not affect distractor processing. Novelty bias and distractor suppression may share the same inhibitory attentional mechanism.     

PRP-paradigm provides evidence for a perceptual origin of the negative compatibility effect

Visual stimuli (primes) that are made invisible by masking can affect motor responses to a subsequent target stimulus. When a prime is followed by a mask which is followed by a target stimulus, an inverse priming effect (or negative compatibility effect) has been found: Responses are slow and frequently incorrect when prime and target stimuli are congruent, but fast and accurate when prime and target stimuli are incongruent. To functionally localize the origins of inverse priming effects, we applied the psychological refractory period (PRP-) paradigm which distinguishes a perceptual level, a central bottleneck, and a level of motor execution. Two dual-task experiments were run with the PRP-paradigm to localize the inverse priming effect relative to the central bottleneck. Together, results of the Effect-Absorption and the Effect-Propagation Procedure suggest that inverse priming effects are generated by perceptual mechanisms. We suggest two perceptual mechanisms as the source of inverse priming effects.     

Context-specific control and the Stroop negative priming effect

The present study highlights the utility of context-specific learning for different probe types in accounting for the commonly observed dependence of negative priming on probe selection. Using a Stroop priming procedure, Experiments 1a and 1b offered a demonstration that Stroop priming effects can differ qualitatively for selection and no-selection probes when probe selection is manipulated between subjects, but not when it is manipulated randomly from trial to trial within subject (see also Moore, 1994). In Experiments 2 and 3, selection and no-selection probes served as two contexts that varied randomly from trial to trial, but for which proportion repeated was manipulated separately. A context-specific proportion repeated effect was observed in Experiment 2, characterized by modest quantitative shifts in the repetition effects as a function of the context-specific proportion repeated manipulation. However, with a longer intertrial interval in Experiment 3, a context-specific proportion repeated manipulation that focused on the no-selection probes changed the repetition effect qualitatively, from negative priming when the proportion repeated was .25 to positive priming when the proportion repeated was .75. The results are discussed with reference to the role of rapid, context-specific learning processes in the integration of prior experiences with current perception and action.     

Selective attention versus selection for action: negative priming is not the result of distractors being unattended

Using a novel referent size-selection task, MacDonald, Joordens, and Seergobin (1999; MacDonald & Joordens, 2000) found that negative priming persisted even when participants were encouraged to attend to distractors before selectively responding to targets. This finding suggested that negative priming is not caused by processes that operate on stimuli that are to be ignored in the traditional selective attention sense. Mackintosh, Mathews, and Holden's (2002) attempt to replicate the MacDonald et al. study resulted in the discovery of possible artifacts in the referent size-selection task, thereby making the implications with respect to the role of attention less clear. In the present study, we describe a different method for directing attention to distractors in a negative priming context, one that does not suffer from the same potential artifacts as the referent size-selection task. Our results are consistent with those found by MacDonald et al., in that negative priming persisted even when participants were explicitly encouraged to attend to distractors. Implications are discussed in the context of the related concepts of selective attention (e.g., Broadbent, 1965) versus selection for action (e.g., Allport, 1987).