Inhibited prime-trial distractor responses solely produce the visual spatial negative priming effect

Responding to a target??s current (probe trial) location is slower when it appears at a former distractor-occupied position (i.e., ignored-repetition [IR] trial), relative to when it arises at a new location (i.e., control trial). This RT(IR) > RT(Control) inequality defines the spatial negative priming (SNP) effect in latency terms. It is uncertain whether the elevated RT(IR) is due to the inhibition of the distractor-occupied location or to the inhibition of this location??s assigned manual response (SNP locus issue). The main aim here was to examine the SNP locus issue. Notably, our SNP design used centrally presented visual events and included having two locations share a common response (many:1 location-to-response mapping) and the use of informative (70?% validity) or uninformative probe-trial response cues. The many:1 mapping trials allowed for the detection of location and response inhibition presence. Results showed that the latter, but not the former, causes inhibitory aftereffects (e.g., SNP) following uninformative response cues. Consistent with this finding, when the informative response cue was valid and was assigned to the many:1 probe response that had just served as the prime distractor response, inhibitory aftereffects were eliminated, when the probe target appeared at the prime distractor position (IR trial) or at a new location (distractor?Cresponse repeat trial). Blocked retrieval of stored distractor-processing representations was proposed as the mechanism for inhibitory aftereffect prevention.     

The use of a distractor-assigned response slows later responding in a location negative priming task

Responding to a target's location takes longer when that location has recently contained a distractor event (ignored-repetition [IR] trial) relative to when it has been unoccupied (control trial). This is known as the location negative priming (NP) effect. We aimed to determine whether the elevated reaction time observed for IR trials was due to the reuse of a distractor location (location locus) and/or to the need to execute a (just inhibited) distractor response (response locus). We isolated these loci latency effects by using many-to-one and one-to-many location-response assignments. Our results showed that reusing a distractor location hastened target processing at that position (facilitative location locus), whereas the production of a distractor response was associated with a time cost (interfering response locus). Accordingly, part of the latency elevation seen with IR trials results from the need on these occasions to execute ajust inhibited (distractor) response, and, hence, the location NP effect has a response locus.     

Spatial negative priming modulation: The influence of probe-trial target cueing,distractor presence,and an intervening response

Reaction times are slower when a target (T) appears at a location that has just contained a distractor (D) (ignored-repetition trial), relative to when it arises at a previously unoccupied spatial position (control trial), i.e., the spatial negative priming (NP) effect. In a typical spatial NP paradigm trials are presented in pairs, first the prime and then the probe. Validly cueing ignored-repetition trials, and/or reducing probe distractor probability, modulated the NP process under certain conditions following target-plus-distractor (prime response) but not after distractor-only (no prime response) primes. This supported the idea that the production of a prime (intervening) response meets the needs for producing NP modulation. Additionally, NP elimination, evident when the probe was randomly distractor-free, was not seen when the probe also contained a distractor event. This suggests that the removal of the NP effect is likely achieved by blocking the retrieval of prime distractor information, rather than by removing the NP cause. Seemingly, the presence of a probe distractor is able to bypass the retrieval block.     

Disengagement of the location negative priming effect: The influence of an intervening response

Reaction time is significantly longer when a target stimulus arises at a location that has just contained a distractor event, relative to when it appears at a new location [i.e., called, the location negative priming (NP) effect]. The NP effect is eliminated when the second of two paired trials (i.e., prime-to-probe trials) predictably lacks a distractor when the preceding trial contains both a target and a distractor event (T+D), but not when a prime distractor appears alone (D-only). We tested the possibility that the failed NP process disengagement seen with D-only prime trials resulted because they do not require the production of an overt intervening response. This possibility was supported. Results also showed that the intervening response had to meet prerequisites; namely, the response had to be prime-generated, i.e., come from the subset of experimental responses and have engaged in a conflict with the prime distractor-activated response.     

Prime-trial processing demands and their impact on distractor processing in a spatial negative priming task

A spatial negative priming (NP) paradigm was used where trials were presented in pairs, first the 'prime' and then the 'probe', and where participants responded manually to a target's location. In Experiment 1, three prime-trial types were used: distractor-plus-target, predictable distractor-only, and unpredictable distractor-only, with prime-probe trial onset delays of 2, 5 or 10 s (NP longevity). In Experiment 2, the latter two prime-trials were employed with onset delays of 75 and 750 ms (distractor response activation-inhibition sequence). With the exception of the 10 s onset delay, the spatial NP effect data (NP size, longevity, distractor response activation-inhibition sequence) was the same for all three prime-trial types. Thus, the varying processing demands associated with each of the prime-trial types (e.g., selection, intervening response) did not alter prime distractor processing so that they differentially contributed to the spatial NP process. The three prime-trial types can be used interchangeably, within limits, to study the NP process.     

Recently inhibited responses are avoided for both masked and nonmasked primes in a spatial negative priming task

Responding to the location of a target is delayed when the target arises at a position previously occupied by a distractor (ignored-repetition trial), relative to when it occurs at a formerly unoccupied location (control trial) [i.e., the spatial negative priming (SNP) effect]. Speculation has held that recently inhibited (distractor) responses resist future execution (i.e., execution resistance [ER]), and thus cause SNP. Evidence for ER has been reported for identity-based tasks using masked prime distractor events. The purpose of this study was to examine the potential impact of ER on response selection in an SNP task for both nonmasked (traditional) and masked primes. We employed a modified SNP task that included nonmasked and masked target-only and distractor-only visual primes (first trial), along with forced choice and free choice probes (second trial). On free choice trials, a selection bias against the prime-distractor-assigned response was evident (same-hand competition, for both nonmasked and masked primes). This selection avoidance was held to reflect ER operating with inhibited prime distractor responses. Further, inhibitory aftereffect patterns were the same for nonmasked and masked distractor primes, and masking target primes transformed a positive to a negative aftereffect, as predicted by the self-inhibition model of mask function set out by Schlaghecken and Eimer (Psychonomic Bulletin & Review, 11, 463-468, 2004).     

The influence of distractor-only prime trials on the location negative priming mechanism

Two experiments were conducted that examined the influence of distractor-only prime trials on the "location" negative priming (NP) effect. In all experiments, the probe trial always lacked a distractor. We showed that the predictable absence of a probe distractor caused the elimination of the location NP effect when the prime trial contained both a target and a distractor event (T + D-->T), but not when the prime contained only a to-be-ignored distractor event (D-->T) (Milliken, Tipper, Houghton, & Lupianez, 2000). The preservation of the NP effect seen with the distractor-only prime trials (D-->T) was not the result of its lacking a prime-trial selection, nor was it the consequence of its representing a higher level of episodic similarity than the T + D-->T condition. Finally, the location NP effect observed for the D-->T condition is seemingly consistent with the view that location NP and the inhibition-of-return effects share a common underlying process (Milliken et al., 2000).     

Can the location negative priming process operate in a proactive manner?

The location negative priming (NP) effect refers to the fact that the processing of a current target stimulus (probe trial) is delayed when it appears at a location that has recently contained a distractor event (prime trial), relative to when it occurs at a previously unoccupied position. One view is that the process causing the NP effect involves the inhibition of the internal representation of the prime-distractor event, and that the future processing of target stimuli that involve this event are prolonged because this distractor inhibition is persistent. In this study, we examined the possibility that the NP process (inhibition) could act proactively; specifically asking whether inhibition could be allocated to a location merely predicted to hold a future distractor event. To do this, we cued the probe distractor's location using an otherwise traditional location NP paradigm. No evidence of a proactive NP process was obtained. Probe-trial target latency was the same whether it appeared at the cued distractor location or at a new location, but was delayed when it occupied the prime-distractor location (NP effect). The location NP process is seemingly a reactive one, applying inhibition only when an actual distractor is present, much as past theories have implied.     

Dilution of compatibility effects in Simon-type tasks depends on categorical similarity between distractors and diluters

The presence of a distracting stimulus during performance of the Stroop color-naming task leads to dilution of the Stroop effect. Because the automatic activation of word meaning may interfere with the task-relevant stimulus feature (text color; stimulus-stimulus [S-S] interference) and the response (saying the text color; stimulus-response [S-R] interference), it is unclear which of these types of interference is diluted. We introduce a new dilution paradigm using word- and arrow-based Simon tasks, in which only S-R interference is present. Participants made a left or right response to a central color target. A task-irrelevant location-word (Experiment 1) or arrow (Experiment 2) distractor adjacent to the target produced S-R compatibility effects. An additional neutral word or symbol series (diluter) was sometimes presented on the opposite side of the target from the distractor. The compatibility effect was smaller when the distractor and diluter category domains matched than when they mismatched. This result provides evidence that S-R compatibility effects are susceptible to the presence of diluters that are categorically similar to the distractors.     

The locus of location repetition latency effects.

We examined the processing locus (location vs. response) of location repetition effects in terms of the event [target (t) or distractor (d)] that initially occupied and then re-occupied the repeated location (i.e., t-to-t, t-to-d, d-to-t, d-to-d). Trials were presented in pairs (prime, then probe) and 2:1 location-to-response mappings were used. Generally, for all repetition conditions, perceptual processing at the repeated location itself was facilitated (location locus), while re-activated responses delayed output production (response locus). More specifically, perceptual facilitation observed for a repeated location was independent of the kind of processing (i.e., t or d) that occurred earlier, suggesting that it is not the labeling of locations as relevant or irrelevant that determines location repetition effects. Response production was significantly slowed only when a just-inhibited response had then to be executed, which supported the view that the spatial negative priming effect has a response locus.     

When do irrelevant visual stimuli impair processing of identical targets?

Three experiments investigated whether the repeated-letter inferiority effect (RLIE) and repetition blindness (RB) are identical phenomena or not and how the RLIE can be reconciled with the flanker compatibility effect (FCE). Participants reported a masked target and ignored an unmasked distractor. We manipulated the type of distractor (identical, alternative target, or neutral), the order of presenting distractor and target, and the predictability of target location. When distractors preceded the targets, distractors identical to the target always caused deficits in target processing (i.e., RB). With simultaneous presentation, identical distractors caused deficits (i.e., an RLIE) for unpredictable target locations only. Yet the RLIE was significantly smaller than RB. This result suggests that simultaneously presented stimuli are identified serially, in random order, if target position is unpredictable. As a result, RB arises only in the 50% of all trials with identical distractors in which the distractor is identified before the target. With simultaneous presentation and predictable target location, however, parallel processing of targets and distractors was possible that gave rise to an FCE in recognition accuracy. Analyses of false alarm rates revealed no evidence of significant response biases.     

The role of probe trial distractors in the production/removal of the spatial negative priming effect

When a current (probe trial) target arises at a location formerly occupied by a distractor event (prime trial; ignored-repetition trial), its reaction time is slower than when it occurs at a previously empty location (control trial), revealing a spatial negative priming (SNP) effect. Here, we examined the influence of prime- and probe trial distractor identity similarity on the retrieval of the stored representations of prime trial processing (i.e., indexed by SNP production), in a context where the prevention of the SNP phenomenon had been motivated (via low probability of probe distractor presence—.25). Two results were important. One, the SNP effect was evident when the prime–probe distractor identities fully matched, but not when they partially or totally mismatched, showing a retrieval role for the probe distractor. Two, target-repeat trial latency facilitation showed the same pattern, indicating that representations of prime target and distractor processing are retrieved together, indicative of an episodic storage format. Since target identity remained fixed, the role of a matching probe distractor identity in SNP production was to presumably complete the triggering requirement (i.e., full event identity matching) for accessing the episodically stored representations.     

Revisiting the role of probe distractors in negative priming: Location negative priming is observed when probe distractors are consistently absent

Negative priming (NP) refers to the delayed response to a probe target that was previously a prime distractor. One peculiar problem in NP literature is the observation that the manifestation of identity NP is contingent on the presence and type of probe distractors. When the probe distractors were completely removed, positive priming, rather than NP, was usually observed. This study investigated whether location NP was affected by the same manipulations. The proportion of ignored repetition trials, attended repetition trials, and control trials was manipulated across Experiments 1–3. These three experiments showed reliable location NP effect when the probe distractor was consistently absent. Experiment 4 showed that the presence of probe distractors did not increase the magnitude of the location NP effect. Experiment 5 showed that the location NP effect observed was not contingent on perceptual mismatching. These findings suggest that the presence of probe distractors is not a necessary component for the manifestation of location NP. Theoretical implications were discussed.     

The error protection impact of inhibitory after-effects in a location-based task and its preservation with practice

In location-based tasks, responses related to (prime trial) distractor-occupied locations automatically undergo activation, followed by inhibition, which causes these responses to become execution-resistant (ER). Distractor-response ER takes time to override, delaying target reactions that later require this response (e.g., probe, ignored-repetition trials), causing the spatial negative priming (SNP) phenomenon. We learned in this study that distractor-response ER affords this output a degree of error protection. Specifically, when the probe target appeared at a new location, former (prime) distractor responses were used erroneously significantly less often than their control response counterparts, likely due to their ER feature, which discourages their inappropriate selection (i.e., “ER” provides error protection). This error protection also was evident when a previous distractor response was activated by a distractor on the probe (i.e., distractor-repeat trial). Notably, error protection remained effective over extensive practice, as did SNP size (i.e., ER override time) after an initial decline.     

Attentional shifts to rare singletons

Five experiments examined whether extremely rare featural singletons (e.g., presented in 4% of all trials) capture attention, and whether this effect could be explained by top-down contingent capture or stimulus-driven singleton capture. To this end, performance (accuracy in Experiments 1–4, reaction time in Experiment 5) in a demanding letter search task was measured in singleton trials that were presented within rare-singleton blocks consisting mainly of no-singleton trials, and in singleton trials that occurred in all-singleton blocks. In separate blocks, either target singletons (i.e., a singleton at target position), or distractor singletons (i.e., a singleton at a distractor position) were presented in each trial. Results are consistent with the contingent-capture view. When the letters were presented briefly and accuracy was the dependent variable, a large performance benefit was obtained, revealing that attention was shifted very fast to the singleton. An examination of search efficiency with a variation of set size and reaction time as the dependent variable revealed a strong gain in search efficiency with a rare target singleton. The large benefit was not accompanied by proportionally large costs for distractor singletons relative to the no-distractor trials. Moreover, a comparison of singleton trials from the all-singleton and from the rare-singleton blocks revealed nonspatial costs for the rare singletons that were of about the same size for target and distractor singletons. In summary, results show that an attentional control setting can remain “dormant” for many trials where it is not applicable, but is then applied nearly as efficiently as when the control setting has been used just recently.     

An attentional-adaptation account of spatial negative priming: Evidence from event-related potentials

Negative priming (NP) refers to a slower response to a target stimulus if it has been previously ignored. To examine theoretical accounts of spatial NP, we recorded behavioral measures and event-related potentials (ERPs) in a target localization task. A target and distractor briefly appeared, and the participant pressed a key corresponding to the target’s location. The probability of the distractor appearing in each of four locations varied, whereas the target appeared with equal probabilities in all locations. We found that response times (RTs) were fastest when the prime distractor appeared in its most probable (frequent) location and when the prime target appeared in the location that never contained a distractor. Moreover, NP effects varied as a function of location: They were smallest when targets followed distractors in the frequent distractor location—a finding not predicted by episodic-retrieval or suppression accounts of NP. The ERP results showed that the P2, an ERP component associated with attentional orientation, was smaller in prime displays when the distractor appeared in its frequent location. Moreover, no differences were apparent between negative-prime and control trials in the N2, which is associated with suppression processes, nor in the P3, which is associated with episodic retrieval processes. These results indicate that the spatial NP effect is caused by both short- and long-term adaptation in preferences based on the history of inspecting unsuccessful locations. This article is dedicated to the memory of Edward E. Smith, and we indicate how this study was inspired by his research career.     

情境特异比例一致变化对冲突效应的影响

采用Hedge和Marsh任务与比例一致性操纵相结合,分别以刺激的空间位置和形状作为比例一致操纵的情境线索,考察刺激-反应联结学习与注意调节在比例一致效应中的作用。结果发现,在情境比例一致操纵下,冲突效应的效应量受到比例一致操纵的影响产生反转。表明刺激-反应联结学习在情境特异比例一致效应中起到主要作用。     

Is automatic imitation a specialized form of stimulus–response compatibility? Dissociating imitative and spatial compatibilities

In recent years research on automatic imitation has received considerable attention because it represents an experimental platform for investigating a number of interrelated theories suggesting that the perception of action automatically activates corresponding motor programs. A key debate within this research centers on whether automatic imitation is any different than other long-term S-R associations, such as spatial stimulus-response compatibility. One approach to resolving this issue is to examine whether automatic imitation shows similar response characteristics as other classes of stimulus-response compatibility. This hypothesis was tested by comparing imitative and spatial compatibility effects with a two alternative forced-choice stimulus-response compatibility paradigm. The stimulus on each trial was a left or right hand with either the index or middle finger tapping down. Speeded responses were performed with the index or middle finger of the right hand in response to the identity or the left-right spatial position of the stimulus finger. Two different tasks were administered: one that involved responding to the stimulus (S-R) and one that involved responding to the opposite stimulus (OS-R; i.e., the one not presented on that trial). Based on previous research and a connectionist model, we predicted standard compatibility effects for both spatial and imitative compatibility in the S-R task, and a reverse compatibility effect for spatial compatibility, but not for imitative compatibility, in the OS-R task. The results from the mean response times, mean percentage of errors, and response time distributions all converged to support these predictions. A second noteworthy result was that the recoding of the finger identity in the OS-R task required significantly more time than the recoding of the left-right spatial position, but the encoding time for the two stimuli in the S-R task was equivalent. In sum, this evidence suggests that the processing of spatial and imitative compatibility is dissociable with regard to two different processes in dual processing models of stimulus-response compatibility.     

Cross-trial priming in visual search for singleton conjunction targets: role of repeated target and distractor features

Kristjánsson, Wang, and Nakayama (2002) demonstrated that visual search for conjunctively defined targets can be substantially expedited ("primed") when target and distractor features are repeated on consecutive trials. Two experiments were conducted to examine whether the search response time (RT) facilitation on target-present trials results from repetition of target-defining features, distractor features, or both. The experiments used a multiple conjunctive search paradigm (adapted from Kristjánsson et al., 2002), in which the target and distractor features were varied (i.e., repeated) independently of each other across successive trials. The RT facilitation was numerically largest when both target and distractor features were repeated, but not significantly larger than that when only distractor features were repeated. This indicates that cross-trial priming effects in conjunctive visual search result mainly from the repetition of distractor, rather than target, features.     

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.