How not to revisit Highway 61: Negative repetition effects in a post-cue naming task

Repetition effects were studied in a post-cue naming task, in which participants were cued to name one of two stimuli following their presentation. When pairs of pictures were repeated in a second block, former distractors (not named in Block 1) were named faster than former targets (named in Block 1). This negative repetition effect was not found when two words rather than two pictures were used or when a semantic categorization task was used with two pictures. From this we conclude that the effect reflects a process of mapping from a semantic representation to a name. Negative repetition was not found with a simultaneous selection cue, suggesting that it arose only when there was competition for name selection. It was also dependent on memory for previous acts of semantic naming. We propose that negative repetition reflects a form of speech monitoring that is applied when there is competition in the process of mapping from semantic to name representations.     

Response conflict reverses priming: a replication

Subjects named target words that followed a masked prime word of 33-msec (Experiments 1A and 1B) or 200-msec (Experiment 2) duration. The target word was either presented alone or accompanied by an interleaved distractor word. Targets presented alone were named more quickly following an identical prime than following an unrelated prime (repetition priming). In Experiment 1A, targets with distractors were named more slowly following an identical prime than following an unrelated prime (negative priming), replicating Milliken, Joordens, Merikle, and Seiffert (Psychological Review, 1998). In Experiments 1B and 2, repetition priming was reduced, although not reversed, for targets with distractors. The results of all three experiments are opposite to the usual finding of enhanced priming for perceptually degraded targets and suggest that response conflict engages retrospective mechanisms that counteract the facilitatory effects of priming.     

Semantic component of a cross-modal Stroop-like task

Three experiments showed that the pattern of interference of single-modality Stroop tests also exists cross-modally. Distractors and targets were either pictures or auditory words. In a naming task (Experiment 1), word distractors from the same semantic category as picture targets interfered with picture naming more than did semantically unrelated distractors; the semantic category of picture distractors did not differentially affect word naming. In a categorization task (Experiment 2), this Stroop-like effect was reversed: Picture distractors from the same semantic category as word targets interfered less with word categorization than picture distractors that were semantically unrelated; the semantic category of word distractors did not differentially affect picture categorization. Experiment 3 replicated these effects when each subject performed both tasks; the task, naming or categorizing, determined the pattern of interference between pictures and auditory words. The results thus support the existence of a semantic component of a cross-modal Stroop-like effect.     

After-effects of responding and of withholding responses in C.RT tasks

The effects of response repetition on choice RT were compared in b-reaction and in c-reaction tasks [Experiments I(a) and I(b)]. The difference in RTs for repeated and for non-repeated responses was found to be less for c-reaction than for b-reaction tasks. This seemed to be because in c-reaction tasks subjects can prepare themselves to make the same response on every trial, so that there is little further RT reduction consequent on immediate response repetition. In b-reaction tasks subjects cannot always prepare to make the same response, so that the difference between response repetition RT and responce alteration RT is greater. Experiment II examined transitions between events in a serial, self-paced C.RT task in which subjects made a different response to each of two signals but withheld any response to the onset of a third. In this task responses were faster when they followed other, different responses than when they followed “no go” trials. The results of these experiments allow us to reject, even for very elementary tasks, a simple “S--R connection network” model for the processes involved in the identification of signals and the production of responses to them.     

Repetition blindness and repetition priming: Effects of featural differences between targets and distractors on RSVP dual-target search

In six experiments, we investigated the influence of featural differences between targets and distractors on the detection and identification of dissimilar and repeated targets in conditions that typically produce an attentional blink and repetition blindness (when a target is repeated). Rapid serial visual presentation streams were presented that contained letter targets and distractors that were either letters or digits. The targets and the distractors were either the same color or a different color and were presented either in the same font or in a differentfont. Dual-target performance on nonrepeat trials was strongly enhanced when the targets were colored. In addition, when subjects used either the color or the font cues to select the targets, there was benefit of repetition on dual-target report, instead of repetition blindness. The results suggest that featural differences between targets and distractors play an important role in registering stimuli as distinct objects.     

Colavita dominance effect revisited: the effect of semantic congruity

To investigate the effect of semantic congruity on audiovisual target responses, participants detected a semantic concept that was embedded in a series of rapidly presented stimuli. The target concept appeared as a picture, an environmental sound, or both; and in bimodal trials, the audiovisual events were either consistent or inconsistent in their representation of a semantic concept. The results showed faster detection latencies to bimodal than to unimodal targets and a higher rate of missed targets when visual distractors were presented together with auditory targets, in comparison to auditory targets presented alone. The findings of Experiment 2 showed a cross-modal asymmetry, such that visual distractors were found to interfere with the accuracy of auditory target detection, but auditory distractors had no effect on either the speed or the accuracy of visual target detection. The biased-competition theory of attention (Desimone & Duncan Annual Review of Neuroscience 18: 1995; Duncan, Humphreys, & Ward Current Opinion in Neurobiology 7: 255–261 1997) was used to explain the findings because, when the saliency of the visual stimuli was reduced by the addition of a noise filter in Experiment 4, visual interference on auditory target detection was diminished. Additionally, the results showed faster and more accurate target detection when semantic concepts were represented in a visual rather than an auditory format.     

Nonword repetition in lexical decision: Support for two opposing processes

We tested and confirmed the hypothesis that the prior presentation of nonwords in lexical decision is the net result of two opposing processes: (1) a relatively fast inhibitory process based on global familiarity; and (2) a relatively slow facilitatory process based on the retrieval of specific episodic information. In three studies, we manipulated speed-stress to influence the balance between the two processes. Experiment 1 showed item-specific improvement for repeated nonwords in a standard “respond-when-ready” lexical decision task. Experiment 2 used a 400-ms deadline procedure and showed performance for nonwords to be unaffected by up to four prior presentations. In Experiment 3 we used a signal-to-respond procedure with variable time intervals and found negative repetition priming for repeated nonwords. These results can be accounted for by dual-process models of lexical decision (e.g., Balota & Chumbley, 1984; Balota & Spieler, 1999).     

Target absent trials in configural contextual cuing

In contextual cuing (CC), reaction times for finding targets are faster in repeated displays than in displays that have never been seen before. This has been demonstrated using target-distractor configurations, global background colors, naturalistic scenes, and covariation of targets with distractors. The majority of CC studies have used displays in which the target is always present. This study investigated what happens when the target is sometimes absent. Experiment 1 showed that, although configural CC occurs in displays when the target is always present, there is no CC when the target is always absent. Experiment 2 showed that there is no CC when the same spatial layout can be both target present and target absent on different trials. The presence of distractors in locations that had contained targets on other trials appeared to interfere with CC, and even disrupted the expression of CC in previously learned contexts (Exps. 3-5). These results show that target-distractor associations are the important element in producing CC and that, consistent with a response selection account, changing the response type from an orientation task to a detection task removes the CC effect.     

Are precues effective in proactively controlling taboo interference during speech production?

ABSTRACT

This research investigated whether precues engage proactive control to reduce emotional interference during speech production. A picture-word interference task required participants to name target pictures accompanied by taboo, negative, or neutral distractors. Proactive control was manipulated by presenting precues that signalled the type of distractor that would appear on the next trial. Experiment 1 included one block of trials with precues and one without, whereas Experiment 2 mixed precued and uncued trials. Consistent with previous research, picture naming was slowed in both experiments when distractors were taboo or negative compared to neutral, with the greatest slowing effect when distractors were taboo. Evidence that precues engaged proactive control to reduce interference from taboo (but not negative) distractors was found in Experiment 1. In contrast, mixing precued trials in Experiment 2 resulted in no taboo cueing benefit. These results suggest that item-level proactive control can be engaged under certain conditions to reduce taboo interference during speech production, findings that help to refine a role for cognitive control of distraction during speech production.     

Stimulus repetition effects on texture-based visual search by pigeons

Four experiments investigated the effects of within-session stimulus repetition on texture discrimination. Six pigeons (Columba livia) searched for a contrasting target region (color or shape) randomly embedded within a larger distractor region for food reinforcement. Experiment 1 found that repeating features of the distractors, but not those of the target, across trials increased the accuracy of target localization relative to baseline. Experiment 2 found that subsequently switching the identity of a repeated distractor feature to the target decreased accuracy. Experiment 3 found that the effects of repeating a distractor feature influenced search performance for at least 60 trials after this learning. Experiment 4 found that differential stimulus-outcome relations can produce control by repeated target features. The results are discussed in terms of the factors and strategies involved in the control of avian visual search behavior.     

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.     

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.     

Use of spatial context is restricted by relative position in implicit learning

For inefficient search, target detection is faster for repeated than for regenerated layouts. This effect, calledcontextual cuing, was assumed to arise from implicit learning of local spatial relationships between targets and distractors. However, a more global influence from distractors far from the target has not been tested. In this study, the search field was divided into upper and lower halves containing a repeated and a regenerated configuration set, respectively. The positions of the two sets were or were not exchanged, meaning that their relative as well as their absolute positions were the same or different (Experiment 1). In Experiment 2, the repeated set appeared alone in either the same or the other half of the screen (same or different absolute position). The contextual cuing effect remained when only absolute position was changed, but not when both absolute and relative positions were changed. These results suggest that contextual cuing depends on relative positional information.     

Task- and location-switching effects on visual attention

In two experiments, we examined the effects of task and location switching on the accuracy of reporting target characters in an attentional blink (AB) paradigm. Single-character streams were presented at a rate of 100 msec per character in Experiment 1, and successive pairs of characters on either side of fixation were presented in Experiment 2. On each trial, two targets appeared that were either white letters or black digits embedded in a stream of black letter distractors, and they were separated by between zero and five items in the stream (lags 1-6). Experiment 1 showed that report of the first target was least accurate if it immediately preceded the second target and if the two targets were either both letters or both digits (task repetition cost). Report of the second target was least accurate if one or two distractors intervened between the two targets (the U-shaped AB lag effect) and if one target was a letter and the other a digit (task switch cost). Experiment 2 added location uncertainty as a factor and showed similar effects as Experiment 1, with one exception. Lag 1 sparing (the preserved accuracy in reporting the second of two targets if the second immediately follows the first) was completely eliminated when the task required attention switching across locations. Two-way additive effects were found between task switching and location switching in the AB paradigm. These results suggests separate loci for their attentional effects. It is likely that the AB deficit is due mainly to central memory limitations, whereas location-switching costs occur at early visual levels. Task-switching costs occur at an intermediate visual level, since the present task switch involved encoding differences without changes in stimulus-response mapping rules (i.e., the task was character identification for both letters and digits).     

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

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

The contribution of morphological and semantic relatedness to repetition priming at short and long lags: Evidence from hebrew

The effect of morphological repetition at lag 0 and at lag 15 on lexical decision was investigated in Hebrew with three types of relation between prime and target. In the semantic-plus-morphological condition (SM), the prime and the target in each pair were two semantically related derivatives of the same root. In the “pure morphological” condition (M), the prime and the target derived from the same root, but their semantic association was very low, or nonexistent. In the semantic priming condition (S), primes and targets were semantically associated but were not morphologically related. The pure semantic relationship produced a significant facilitation at lag 0 that disappeared completely at lag 15. The pure morphological relation produced (smaller but) significant facilitation at lag 0 that was not attenuated at lag 15. When prime and target were semantically as well as morphologically related, the facilitation at lag 0 was similar to semantic priming, whereas at lag 15 it was similar to the pure morphological effect. Significant repetition effects at both lags were also found with non-words that shared the same (nonsensical) root and differed with respect to real derivational affixes. The differential time course for facilitation due to semantic and morphological relatedness suggests distinct underlying processes, although at lag 0 it is possible that semantic relatedness may augment the morphological repetition effect. Morphological repetition probably facilitates the retrieval of lexical information that, under certain circumstances, is necessary for lexical decision.     

Spacing effects in cued-memory tasks for unfamiliar faces and nonwords

Memory for repeated items improves as the interval between repetitions in a list increases (the spacing effect). This study investigated the spacing effect in recognition memory and in a frequency judgment task for unfamiliar target faces that were repeated in the same or in a different pose during incidental learning. Changing the pose between prime and probe trials reduced perceptual repetition priming in a structural discrimination task and also reduced the spacing effect in a subsequent unexpected recognition memory task. Three further experiments confirmed that the spacing effect inrecognition memory (Experiments 2 and 4) or frequency judgment (Experiment 3) was reduced when the pose was changed between repeated presentations at study. Similarly, with nonwords as targets (Experiment 5), changing the font between repeated occurrences of targets at study removed the spacing effect in a subsequent unexpected recognition memory test. These results are interpreted to support the view that short-term perceptual repetition priming underlies the spacing effect in explicit cued-memory tasks for unfamiliar nonsense material.     

Bigger than a breadbox? Attention to distractors may not enhance negative priming

In several recent studies, P. A. MacDonald and colleagues (e.g., P. A. MacDonald & S. Joordens, 2000) reported unusually large negative priming effects and claimed that attention to distractors, counter to expectations, served to enhance the magnitude of the effect. In 3 experiments using their novel comparative judgment task, negative priming was assessed using both a control condition based on that of P. A. MacDonald, S. Joordens, and K. N. Seergobin (1999) and one in which control probe items exactly matched those on ignored repetition trials. In MacDonald et al.'s unmatched control condition, participants were faster than on ignored repetition trials, but this difference was reduced or absent when control items were matched. This result led to the conclusion that the apparently large negative priming effect reported by MacDonald and colleagues may be an artifact arising because judgments for a subset of their control trials were relatively easier than for ignored repetition trials.     

The fate of unattended stimuli and emotional habituation: Behavioral interference and cortical changes

The interference produced by the viewing of emotional distractors has been interpreted as evidence that emotional cues are processed in a fairly mandatory fashion, and that they divert attention from the primary ongoing task. However, few studies have examined how behavioral emotional interference varies with repeated presentation of the same emotional distractors. In two experiments, while participants were engaged in a parity judgment task, we investigated the effects of repetition of task-irrelevant emotional pictures, as reflected in both behavioral interference (Experiments 1 and 2) and neural activity (Experiment 2). Both experiments showed that the slowing of reaction times that was observed when viewing emotional, compared to neutral, scenes disappeared after only a few repetitions, suggesting diminished attention allocation to repeated emotional pictures. Conversely, in Experiment 2, neural correlates of picture processing revealed that the late positive potential (LPP) amplitude continued to be enhanced for emotional, compared to neutral, distractors despite picture repetition and the presence of a concurrent task. Altogether, these findings suggest that while evaluative processes are mandatory, and continue to engage cortico-limbic appetitive and defensive systems even after massive repetition, as suggested by the affective modulation of the LPP, attentional processes are not necessary after several repetitions of the same stimulus, as indicated by the rapid decline of behavioral emotional interference.     

Contextual cueing in multiple object tracking

In this study, we examined whether visual context can be learned through a dynamic display and whether it can facilitate sustained attentional tracking by combining a multiple object tracking (MOT) task and a contextual cueing procedure. The trajectories of the targets and distractors in the MOT task were made invariant by repeatedly presenting them. The results revealed that when the targets were repeatedly displayed, tracking performance implicitly improved, and this effect was enhanced when the unattended distractors in the displays were also repeated. However, the repetition of the distractors alone did not produce any effect. Interestingly, when the targets and distractors were switched in a display in which the distractors had been previously repeated, the tracking performance was impaired as compared with that in the case of nonrepeated displays. We concluded that the contextual information in a dynamic display facilitates attentional tracking and that different types of contextual modulations occurred in MOT processes, such as facilitation for attended targets and inhibition for ignored distractors.