The emotional memory effect: Differential processing or item distinctiveness?

A color-naming task was followed by incidental free recall to investigate how emotional words affect attention and memory. We compared taboo, nonthreatening negative-affect, and neutral words across three experiments. As compared with neutral words, taboo words led to longer color-naming times and better memory in both within- and between-subjects designs. Color naming of negative-emotion nontaboo words was slower than color naming of neutral words only during block presentation and at relatively short interstimulus intervals (ISIs). The nontaboo emotion words were remembered better than neutral words following blocked and random presentation and at both long and short ISIs, but only in mixed-list designs. Our results support multifactor theories of the effects of emotion on attention and memory. As compared with neutral words, threatening stimuli received increased attention, poststimulus elaboration, and benefit from item distinctiveness, whereas nonthreatening emotional stimuli benefited only from increased item distinctiveness.     

Lexical decision in children: sublexical processing or lexical search?

Length effects in the lexical decision latencies of children might indicate that children rely on sublexical processing and essentially approach the task as a naming task. We examined this possibility by means of the effects of neighbourhood size and articulatory suppression on lexical decision performance. Sixty-six beginning and 62 advanced readers performed a lexical decision task in a standard, articulatory suppression, or tapping condition. We found length effects on words and nonwords in the children's lexical decisions. However, the effects of neighbourhood size were similar to those reported for adult lexical decisions, rather than the effects previously found in children's naming. In addition, no effect was found of articulatory suppression. Both findings suggest that, despite clear length effects, children do not adopt a naming task approach but, like adults, base lexical decisions mainly on a lexical search. These results pose a challenge for several computational models of reading.     

Lexical processing of ambiguous words: dominance or associative strength?

Four experiments examined the role of meaning frequency (dominance) and associative strength (measured by associative norms) in the processing of ambiguous words in isolation. Participants made lexical decisions to targets words that were associates of the more frequent (dominant) or less frequent (subordinate) meaning of a homograph prime. The first two experiments investigated the role of associative strength at long SOAs (Stimulus Onset Asynchrony) (750 ms.), showing that meaning is facilitated by the targets' associative strength and not by their dominance. The last two experiments traced the role associative strength at short SOAs (250 ms), showing that the manipulation of the associative strength has no effect in the semantic priming. The conclusions are: on the one hand, semantic priming for homographs is due to associative strength manipulations at long SOAs. On the other hand, the manipulation of the associative strength has no effect when automatic processes (short SOAs) are engaged for homographs.     

The mechanism of priming: episodic retrieval or priming of pop-out?

Previous studies indicate that priming affects attentional processes, facilitating processes of target detection and selection on repetition trials. However, the results are so far compatible with two different attentional views that propose entirely different mechanisms to account for priming. The priming of pop-out hypothesis explains priming by feature weighting processes that lead to more frequent selections of nontarget items on switch trials. According to the episodic retrieval account, switch trials conversely lead to temporal delays in retrieving priority rules that specify the target. The results from two eye tracking experiments clearly favour the priming of pop-out hypothesis: Switching the target and nontarget features leads to more frequent selection of nontargets, without affecting the time-course of saccades to a great extent. The results from two more control experiments demonstrate that the same results can be obtained in a visual search task that allows only covert attention shifts. This indicates that eye movements can reliably indicate covert attention shifts in visual search.     

The masked onset priming effect in naming: computation of phonology or speech planning?

We investigated factors that modulate the presence of the masked onset priming effect in three naming experiments. In Experiment 1, we showed that the masked onset priming effect is found with regular words, but not with exception words, replicating the finding reported by Forster and Davis (1991). In Experiment 2, we used the conditional naming task in which words are mixed with nonwords and participants are instructed to name the item only if it is a word. The masked onset priming effect was eliminated in this experiment, but the regularity effect remained. In Experiment 3, regular and irregular words were mixed randomly, rather than in separate blocks as in Experiment 1. This reduced the size of the regularity effect, and the masked onset priming effect was again absent. We argue that these results, taken as a whole, are better interpreted within the view that the masked onset priming effect has its origin in the preparation of a speech response, rather than within the original dual-route interpretation proposed by Forster and Davis.     

Lexical guidance in sentence processing?

An eyetracking experiment was conducted to explore a self-paced reading effect reported by Mitchell (1987). Mitchell found that a noun phrase (NP) was read slowly when it immediately followed an intransitive verb, as long as the verb and NP appeared in the same presentation region. This effect has been used to support the claim that verb subcategorization information is not used initially in sentence parsing. However, the effect did not appear in the eyetracking experiment reported in the present paper, supporting criticisms that Mitchell’s segmentation procedure distorted the parsing process.     

The laterality effect: myth or truth?

Tzelgov and colleagues [Tzelgov, J., Meyer, J., and Henik, A. (1992). Automatic and intentional processing of numerical information. Journal of Experimental Psychology: Learning, Memory and Cognition, 18, 166-179.], offered the existence of the laterality effect as a post-hoc explanation for their results. According to this effect, numbers are classified automatically as small/large versus a standard point under autonomous processing of numerical information. However, the genuinity of the laterality effect was never examined, or was confounded with the numerical distance effect. In the current study, I controlled the numerical distance effect and observed that the laterality effect does exist, and affects the processing of automatic numerical information. The current results suggest that the laterality effect should be taken into account when using paradigms that require automatic numerical processing such as Stroop-like or priming tasks.     

The processing of non-target words: Semantic or not?

It is known that people reacting to visual words may be affected by the meaning of accompanying non-target words. On the approach to perception developed by Treisman (e.g. 1986), this is surprising, because meaning might be thought to require analysis of conjunctions of physical features and so should remain uncomputed for non-target words. Treisman's approach does, however, assert that analysis of the target may unleash further processes that would prime the system for detection of related words. If this were so, then presentation of the target earlier than the distractors would increase the effect of the latter; whereas if analysis of non-targets were independent of priming, they might be expected to have a smaller effect when delayed. Further, if the sets of words involved are small and familiar, then individual features of primed non-targets, rather than conjunctions of features, might trigger interference. They might especially do so when spatial separation of target and non-target is small.

Five experiments using a paradigm developed by Shaffer and LaBerge confirm that the meaning of non-target words affects response to targets; but (1) this is more true for early than for late arrival of the target; (2) it is affected by target/non-target separation in space; (3) it is true for familiar sets of repeated words but not, in these data, for words used once only in the experiment. It is therefore concluded that the results are more consistent with a Treisman type of explanation than with a theory of universal and automatic full analysis.     

The unattended speech effect: perception or memory?

Broadbent (1983) has suggested that the influence of unattended speech on immediate serial recall is a perceptual phenomenon rather than a memory phenomenon. In order to test this, subjects were required to classify visually presented pairs of consonants on the basis of either case or rhyme. They were tested both in silence and against a background of continuous spoken Arabic presented at 75 dB(A). No effect of unattended speech was observed on either the speed or accuracy of processing. A further study required subjects to decide whether visually presented nonwords were homophonous with real words. Again, performance was not impaired by unattended speech, although a clear effect was observed on an immediate serial memory task. Our results give no support to the perceptual interpretation of the unattended speech effect.     

The list-strength effect: Strength-dependent competition or suppression?

If several items are associated with a common cue, the cued recall of an item is often supposed to decrease as a function of the increase in strength of its competitors' associations with the cue. Evidence for such a list-strength effect has been found in prior research, but this effect could have been caused both by the strength manipulations and by retrieval-based suppression, because the strengthening and the output order of the items were confounded. The experiment reported here employed categorizable item lists; some categories in each list contained strong items only, some contained weak items only, and some contained both strong and weak items. Strengthening was accomplished by varying the exposure time of the items. The testing sequence of the items from each category was controlled by the use of category-plus-first-letter cues. When the typical confounding of strengthening and output order was mimicked, list-strength effects were found, which is consistent with prior research. However, when this confounding was eliminated, the list-strength effects disappeared: The recall of neither strong nor weak items varied with the strengths of the other category exemplars. This pattern of results indicates that the list-strength effect is not the result of strength-dependent competition, but is caused by output-order biases and a process of suppression.     

The Bransford-Franks linear effect: Integration or artifact?

It was hypothesized that the Bransford-Franks linear effect is an artifact of the method of presentation of stimulus sentences and is unrelated to semantic processes. Ss were given sentences containing the same information in one of two ways. In a control condition, which was identical to the procedure used in earlier research, overlapping combinations of ideas were presented during learning and recognition; in an experimental condition, ideas were presented one at a time. Results demonstrated that one-idea sentences received significantly higher recognition confidence ratings in the experimental condition, thus supporting the artifact interpretation. It was proposed that Ss assign recognition confidence ratings based on the probability that a sentence containing a certain number of ideas could have occurred in acquisition.     

The persistence of structural priming: transient activation or implicit learning?

Structural priming in language production is a tendency to recreate a recently uttered syntactic structure in different words. This tendency can be seen independent of specific lexical items, thematic roles, or word sequences. Two alternative proposals about the mechanism behind structural priming include (a) short-term activation from a memory representation of a priming structure and (b) longer term adaptation within the cognitive mechanisms for creating sentences, as a form of procedural learning. Two experiments evaluated these hypotheses, focusing on the persistence of structural priming. Both experiments yielded priming that endured beyond adjacent sentences, persisting over 2 intervening sentences in Experiment 1 and over 10 in Experiment 2. Although memory may have short-term consequences for some components of this kind of priming, the persisting effects are more compatible with a learning account than a transient memory account.     

Lexical access without attention? Explorations using dichotic priming

The authors used lexical decision in a dichotic listening situation and measured identity priming across channels to explore whether unattended stimuli can be processed lexically. In 6 experiments, temporal synchronization of prime and target words was manipulated, and acoustic saliency of the unattended prime was varied by embedding it in a carrier sentence or in babble speech. When the prime was acoustically salient, a cross-channel priming effect emerged, and participants were aware of the prime. When the prime was less salient, no identity priming was found, and participants failed to notice the prime. Saliency was manipulated in ways that did not degrade the prime. Results are inconsistent with models of late filtering, which predict equal priming irrespective of prime saliency.     

The effect of recognizability on figure-ground processing: does it affect parsing or only figure selection?

Though figure-ground assignment has been shown to be probably affected by recognizability, it appears sensible that object recognition must follow at least the earlier process of figure-ground segregation. To examine whether or not rudimentary object recognition could, counterintuitively, start even before the completion of the stage of parsing in which figure-ground segregation is done, participants were asked to respond, in a go/no-go fashion, whenever any out of 16 alternative connected patterns (that constituted familiar stimuli in the upright orientation) appeared. The white figure of the to-be-attended stimulus-target or foil-could be segregated from the white ambient ground only by means of a frame surrounding it. Such a frame was absent until the onset of target display. Then, to manipulate organizational quality, the greyness of the frame was either gradually increased from zero (in Experiment 1) or changed abruptly to a stationary level whose greyness was varied between trials (in Experiments 2 and 3). Stimulus recognizability was manipulated by orientation angle. In all three experiments the effect of recognizability was found to be considerably larger when organizational quality was minimal due to an extremely faint frame. This result is argued to be incompatible with any version of a serial thesis suggesting that processing aimed at object recognition starts only with a good enough level of organizational quality. The experiments rather provide some support to the claim, termed here "early interaction hypothesis", positing interaction between early recognition processing and preassignment parsing processes.     

Lexical and Metrical Stress in Word Recognition: Lexical or Pre-lexical Influences?

The influence of lexical stress and/or metrical stress on spoken word recognition was examined. Two experiments were designed to determine whether response times in lexical decision or shadowing tasks are influenced when primes and targets share lexical stress patterns (JUVenile–BIBlical [Syllables printed in capital letters indicate those syllables receiving primary lexical stress.]). The results did not support an effect of lexical stress on the organization of lexical memory. In Experiment 3 primes and targets whose first syllables shared lexical stress only (MUDdy–PASta), metrical stress only (alTHOUGH–PASta), both cues (LECtern–PASta), or neither cue (conTROL–PASta) revealed no priming effect. However, targets whose first syllables were strong were responded to faster than targets whose first syllables were weak. Experiment 4 manipulated the metrical stress patterns of bi-syllabic primes and targets. Targets with strong–weak metrical stress patterns were responded to more quickly than those with strong–strong or weak–strong patterns. Although the priming paradigm did not reveal an influence of lexical and metrical stress on the organization of lexical memory, the data do support an influence of strong syllables on the processing of auditorily presented words.     

Preattentive processing or prefocal processing?

The concept of preattentive processing is analyzed and alternative views of it are presented. A basic question is whether processing required for preattentive input selection is qualitatively different from post-selection processing. In order to study this, subjects were presented in one set of conditions with one stimulus at either of two locations, and in another set of conditions, simultaneously with two stimuli. The stimuli could be green or red, or large or small. Subjects were asked to indicate the location (or the color, or the size) of the single stimulus in the single-stimulus conditions, or of a predesignated stimulus (say, the red one) in the dual-stimulus conditions. Responses were generally slower in the dual-stimulus conditions. The increases in reaction time were accounted for by the times it takes to process for response selection the properties by which the target stimulus could be selected, as indicated by the results of two control conditions. The results as well as some other considerations do not support the view that preattentive processing is necessarily of a type that qualitatively differs from post-selection processing.     

The bilateral effect: callosal inhibition or intrahemispheric competition?

The magnification of visual field asymmetry observed with bilateral compared to unilateral tachistoscopic presentation of homologous stimuli (bilateral effect) can be explained by two hypothetical processes: homologous activation with subsequent inhibition of callosal information transfer or intrahemispheric competition for processing resources. A lexical decision task with unilateral and bilateral stimulation and response with the right or left hand was used in an attempt to decide between these hypotheses. Analysis of response time data revealed a bilateral effect, superimposed on a right visual field advantage, and no interaction between visual field and response hand. Results are consistent with the hypothesis of intrahemispheric competition in the left hemisphere.     

The word-detection effect: Sophisticated guessing or perceptual enhancement?

Subjects discriminate letters in words better than letters in nonwords. The sophisticated guessing hypothesis attributes this word advantage to a guessing strategy. In words, the possible letters at each letter position are constrained by letters at other positions, whereas letters in nonwords are not restricted in this manner. A critical test of this hypothesis is that if subjects are givenexplicit knowledge of the letters in nonwords before the trial, the word advantage would disappear. We investigated the effect of preknowledge of the alternatives in the word-detection effect. In the word-detection effect, subjects decide which of two character strings contains letters and which contains pseudoletters. In four experiments, subjects were more accurate with words than with nonwords, and subjects were more accurate when they were told the word or nonword before the trial. However, even with foreknowledge of the alternatives, subjects were more accurate with words than with nonwords.     

Semantic priming: subliminal perception or context?

Briefly presented, masked priming stimuli that cannot be identified by themselves can affect the processing of subsequent targets. The effect, which is sometimes viewed as a demonstration of unconscious processing, has been linked to the subliminal perception literature. Experiments 1 and 2 indicated that the identification of primes in the context of semantically related targets is superior to the identification of primes presented alone, and that the identification of primes in the context of semantically unrelated targets is inferior to the identification of primes presented alone. Experiment 3 indicated parallel findings in a recognition task. Consequently, an explanation of semantic priming in terms of the interactive nature of stimuli that are near to one another in time seems preferable to one based upon concepts of unconscious processing and subliminal perception.