Another look at the effect of a surprising intervening event on negative priming.

Tipper et al. (1991) reported that negative priming is eliminated when a low-probability event separates presentation of the prime display from the probe display. This finding is perfectly consistent with at least three of the major accounts of negative priming. However, each of these accounts can reasonably be argued to make different predictions regarding the effect of a surprising intervening event on attended repetition effects. The purpose of the experiment reported here was to determine which of these three predictions was correct. The results obtained were consistent with none of the three predictions. The low-probability intervening event did eliminate negative priming, but did so by slowing performance in the baseline condition relative to all other conditions. The results are discussed with respect to the role of surprise in responding to novel events.     

Another look at semantic priming without awareness

In a recent study, McCauley, Parmelee, Sperber, and Carr (1980) reported results indicating that semantic priming had been produced by visual stimuli that were backward masked at durations too brief for greater than chance report. The conclusions drawn from such an experiment are critically dependent upon whether or not the primes were actually masked below the thresh-old for identification during priming trials. The three experiments reported here provide evidence that this requirement was not met. Rather, McCauley et al.’s (1980) methodology allowed for an uncontrolled increase in light adaptation during the actual testing of prime efficacy in the priming session. This increase in light adaptation reduced the effectiveness of the backward mask and resulted in an increase in prime visibility during priming trials. Thus, semantic priming probably occurred under conditions in which commensurate visual information was actually available.     

On the time course of letter perception: A masked priming ERP investigation

In an experiment measuring event-related brain potentials (ERPs), single-letter targets were preceded by briefly presented masked letter primes. Name and case consistency were manipulated across primes and targets so that the prime was either the same letter as the target (or not), and was presented in the same case as the target (or not). Separate analyses were performed for letters whose upper- and lowercase forms had similar features (or not). The results revealed an effect of prime-target visual similarity between 120 and 180 msec, an effect of case-specific letter identity between 180 and 220 msec, and an effect of case-independent letter identity between 220 and 300 msec. We argue that these ERP results reflect processing in a hierarchical system for letter recognition that involves both case-specific and case-independent representations of alphabetic stimuli.     

A time course analysis of the affective priming effect

The argument that automatic processes are responsible for affective/evaluative priming effects has been primarily based on studies that have manipulated the stimulus onset asynchrony (SOA; i.e., the interval between the onset of the prime and the onset of the target). Moreover, these SOA studies provide an insight in the time course of the activation processes underlying automatic affect/attitude activation. Based on a fine-grained manipulation of the SOA employing either the evaluative decision task (Experiment 1) and the pronunciation task (Experiment 2) we concluded that affective priming, and hence automatic affect activation, is based on fast-acting automatic processes. The results of Experiment 3 provide a valid explanation for an apparent discrepancy between the results of Experiments 1 and 2 and previous findings. Finally, the results of Experiment 3 support the prediction of Jarvis and Petty (1996) that affective priming effects should be stronger for participants who are more chronically engaged in conscious evaluations.     

On finding negative priming from distractors

Negative priming from distractors has attracted considerable interest because it appears to reveal a fundamental mechanism of selective attention. Recently, the phenomenon has become muddled because it can be explained in far too many ways. This may partly be because the empirical foundation for the phenomenon has been handicapped by an overreliance on a simplistic comparison of a single experimental condition with control. A sounder approach requires that we collect data that can rule out alternatives to the hypothesis we might favor or test. Regardless of the paradigm used, we propose collecting data from a much fuller set of conditions than is typical. Despite the variety of underlying explanations, we show that the various theories that attribute negative priming to ignoring the distractor predict a common pattern of results across the full set of related conditions. Theories, such as inhibition of return, that do not attribute the cost in performance to ignoring the distractor do not predict this pattern.     

Temporal parameters and time course of perceptual latency priming

Visual stimuli (primes) reduce the perceptual latency of a target appearing at the same location (perceptual latency priming, PLP). Three experiments assessed the time course of PLP by masked and, in Experiment 3, unmasked primes. Experiments 1 and 2 investigated the temporal parameters that determine the size of priming. Stimulus onset asynchrony was found to exert the main influence accompanied by a small effect of prime duration. Experiment 3 used a large range of priming onset asynchronies. We suggest to explain PLP by the Asynchronous Updating Model which relates it to the asynchrony of 2 central coding processes, preattentive coding of basic visual features and attentional orienting as a prerequisite for perceptual judgments and conscious perception.     

The time course of response inhibition in masked priming

In two experiments, we studied the temporal dynamics of the response time effects of masked visual prime stimuli, as a function of stimulus eccentricity and size. Experiment 1 factorially varied prime-target congruency, eccentricity, and mask-target stimulus onset asynchrony. Early facilitative and late inhibitory effects of congruency were observed at all eccentricities, with temporal dynamics modulated by eccentricity. To test whether this dependence on eccentricity is due to cortical magnification, Experiment 2 varied stimulus size as well. Response inhibition time courses were influenced by size and eccentricity jointly, with no discernible difference when stimuli were matched for cortical magnification. Analysis of the individual time course data revealed that the timescale of inhibition changes with the strength of the cortical representation of the prime stimulus. This imposes constraints on possible models.     

Revisiting the time course of inter-trial feature priming in singleton search

Current theories of the locus of inter-trial priming effects in efficient visual search posit an early perceptual component that reflects the short-term influence of a memory trace for low-level stimulus attributes. Despite the fact that this memory trace is hypothesized to be short term, and should therefore have a diminishing influence on performance over time, there has been relatively little study of the effect of time alone on singleton priming effects. The present series of experiments addresses this issue by systematically examining the effect of time on the priming of pop-out (PoP) effect. In Experiment 1, we show that the PoP effect does indeed diminish with increases in the RSI between trials, and does so in accord with a power-law function. In Experiment 2, we show that temporal discriminability of trial n ? 1 from the trial that precedes it does not contribute to PoP effects. The results of Experiment 3 revealed two key results: (1) the PoP effect survives an equivalent number of intervening trials across very different RSI conditions; and (2) the cumulative target repetition benefit does depend on the RSI between trials. Together, the results favor neither a simple passive decay nor a strong episodic retrieval account of the PoP effect.     

An investigation of time course of category and semantic priming

Low semantically similar exemplars in a category demonstrate the category-priming effect through priming of the category (i.e., exemplar-category-exemplar), whereas high semantically similar exemplars in the same category demonstrate the semantic-priming effect (i.e., direct activation of one high semantically similar exemplar by another). The author asked whether the category- and semantic-priming effects are based on a common memory process. She examined this question by testing the time courses of category- and semantic-priming effects. She tested participants on either category- or semantic-priming paradigm at 2 different time intervals (6 min and 42 min) by using a lexical decision task using exemplars from categories. Results showed that the time course of category priming was different from that of semantic priming. The author concludes that these 2 priming effects are based on 2 separate memory processes.     

Jaynes' chimeric faces: Another look into the mirror

In The Origin of Consciousness in the Breakdown of the Bicameral Mind, Jaynes (1976) presented a technique—involving the selection of the happier of two line-drawing chimeric faces—that is theorized to measure hemispheric laterality. Certain imperfections in the published stimuli have led some critics to question the task's validity, while others maintain that even the flawed stimuli are measuring some aspect of laterality. In this study, further data are presented to show that this task, despite its inherent biases, is still sensitive to differences in perception between left-handers and right-handers. The implications of this sensitivity are discussed.     

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.     

Exploring the time course of semantic interference and associative priming in the picture-word interference task

The picture-word interference (PWI) task is a widely used technique for exploring effects of semantic context on lexical access. In this task, printed words are superimposed over pictures to be named, with the timing of the interfering word relative to the picture systematically manipulated. Two experiments (N = 24 adults in each) explored the time course of effects of associates (e.g., CARROT superimposed on a picture of a rabbit) versus coordinates (e.g., CHIPMUNK superimposed on a picture of a rabbit) on naming latencies. Associates led to faster picture naming than did unrelated words, with facilitative effects occurring at stimulus onset asynchronies (SOAs, in ms) ranging from -450 to 0. Coordinates led to slower naming latencies, with the interference effect restricted to SOAs of -150 and 0. The overlapping time course of associative priming and coordinate interference provides important constraints on models of lexical access in speech production.     

The time course of negative repetition effects in post-cue naming

It has previously been shown that when picture pairs are repeated across blocks in a post-cue naming task, former distractors are named faster than former targets: the “negative repetition effect” (Mayall, Humphreys, & Kotsanis, 2002). In the present study the time course of this effect was examined. Experiment 1 demonstrated that the effect became apparent after a lag of only two intervening trials, with former targets being named faster than former distractors after a lag of zero trials. Experiment 2 used a new baseline condition with repeated picture pairs for which no response was required on the first presentation. Comparisons with this baseline indicated that the negative repetition effect is the result of suppression of former targets as opposed to facilitation of former distractors. The results support the proposal of Mayall et al. that the negative repetition effect reflects a form of speech monitoring that is applied when there is competition in the process of mapping from semantics to name representations.