Semantic congruity and lexical marking in symbolic comparisons: An expectancy hypothesis

Lexical marking and semantic congruity effects were investigated in four symbolic size comparison experiments. Predictions followed from an expectancy hypothesis suggested by results of recent comparative judgment studies. According to the present position, lexical marking and semantic congruity should be mutually exclusive effects in such tasks, and the demonstration of either dependent upon the order in which the stimuli and the comparative term are evaluated. When the comparative precedes the stimuli, an expectancy is created whereby the subject is more likely to be prepared for, say, large items following the comparative “larger” and small items following the comparative “smaller.” In addition, the usual advantage of unmarked as compared to marked comparisons should be offset by the initial processing of the comparative. As predicted, the comparative-stimulus presentation order produced a significant semantic congruity effect and no effect of lexical marking in Experiment 1. Conversely, when stimuli precede the comparative, or are presented simultaneously with it, no expectancy should be created, as the items are immediately available to the subject, and the semantic congruity effect should not be obtained. Upon presentation of the comparative, however, unmarked comparisons should be easier than marked comparisons. Experiments 2 and 4 confirmed these expectations, as significant lexical marking effects were obtained and significant congruity effects were not. These findings are contrary to predictions derived from a semantic coding interpretation of the symbolic comparison process.     

Semantic congruity in symbolic comparisons: Salience,expectancy, and associative priming

An expectancy interpretation of semantic congruity effects suggests that in symbolic comparisons involving the typical comparative-then-stimuli paradigm, the comparative acts as a cue in priming memory for related stimuli. A recent study by Holyoak and Mah (1981) presented evidence purported to disconfirm this hypothesis insofar as a congruity effect also was obtained when the stimuli preceded the comparative. The present study showed the stimulicomparative effect to be a consequence of the pairing of stimuli with particularly salient comparatives such that the former could serve the cuing function. This finding is consistent with the expectancy hypothesis in emphasizing the role of a flexible encoding process but inconsistent with the view that only comparatives can create expectancies in symbolic comparisons.     

Semantic congruity and expectancy as separate processes

In two experiments, we investigated the role of expectancy in producing congruity effects in comparative judgment. In Experiment 1, instructions to choose the larger or smaller term either preceded pairs for comparative judgment or preceded individual words for lexical decision. If expectancy in interpreting the comparative judgment terms accounts for the congruity effect, the lexical decision task also should show a congruity effect. However, there were large congruity effects in comparative judgment but not in lexical decision. In this experiment, we used an infiniteset design to make sure that semantic information was needed on comparative judgment trials. In Experiment 2, comparative judgment pairs were preceded by a prime word that either was or was not a category label for the terms in the pairs. There were both congruity and priming effects, with no interaction between the two. This result implies that expectancy and the semanticcongruity effect come from separate processes.     

Semantic congruity and expectancy in symbolic judgments

These experiments assess the degree to which the semantic-congruity effect in comparative judgment can be explained by such expectancy effects as priming, perceptual "set," or strategies used in the task. The first experiment mixed a lexical-decision task with the comparative-judgment task and showed that neither automatic semantic priming nor deliberate preparation can account for the congruity effect. Experiments 2-4 assessed expectancy effects in a different way by presenting the instructions for comparative judgment either before or after the pair to be judged. These experiments included, among other things, a number of safeguards against artifacts in this paradigm. In these three experiments the congruity effect was obtained with both orders of stimuli and instructions, contrary to the prediction of an expectancy hypothesis. The results indicate that when stimuli are not degraded. The semantic-congruity effect depends largely on the relation between the stimuli and the instructions and only to a small degree, if at all, on expectancy.     

Congruity and the perceptual comparison task

The effects of congruity between comparatives and the relative magnitudes of to-be-compared stimuli were investigated in six perceptual comparison experiments. Experiments 1-5 failed to obtain congruity effects in purely perceptual tasks even when subjects had extensive practice with a relatively small stimulus set. Experiment 6 obtained a congruity effect with perceptual stimuli but only when the stimuli were described as representing real-world objects. All of the results indicated that congruity effects occur only in tasks that include major symbolic or memorial components; a review of the perceptual comparison literature reveals consistent support for this position. These findings are discussed in terms of expectancy and semantic coding interpretations of the congruity effect.     

Semantic congruity effects in perceptual comparisons

Semantic congruity effects occur when, as in Experiment 1, for example, the time to select the shorter of two relatively short lines is faster than the time to select the longer; conversely, selection of the longer of two relatively long lines is faster than selection of the shorter. Semantic congruity effects are also demonstrated in experiments requiring comparisons of the heaviness of weights (Experiment 2) and horizontal extent (Experiment 3). In Experiment 1, the magnitude of the semantic congruity effect was larger under conditions emphasizing accuracy rather than speed and when the comparison was difficult. In fact, when comparisons were errorless, the effect was minimal (20 msec), thereby replicating previous failures to obtain the effect with supraliminal perceptual comparisons (Banks, Mermelstein, & Yu, 1982; Marschark & Paivio, 1981; Petrusic & Baranski, 1988a). In confirmation of Henmon's (1911) introspective analyses of psychophysical comparisons, Experiments 2 and 3 extend the range of the semantic congruity effect to include judgments of confidence. However, in each of the three experiments, semantic congruity effects were not evident with the response-accuracy measure. Finally, using highly confusable stimuli, in Experiment 3 the magnitude of the semantic congruity effect was shown to be larger for error than for correct response times. The implications of these findings for a decisional locus of the effect and for the semantic coding theory are discussed.     

The role of expectancy in comparative judgments

Researchers interested in the processing of relational information have sought a satisfactory explanation for the congruity effect in linear orders. It is relatively easy to select either the greater of two objects that are high on a dimension or the lesser of two objects that are low on a dimension, but it is relatively difficult to determine the greater of two objects that are low in magnitude or the lesser of two objects that are high in magnitude. One explanation of the congruity effect is the expectancy hypothesis that claims that the choice of the comparative primes objects of particular magnitudes. We present two experiments that demonstrate that a congruity effect of equivalent magnitude is obtained when the comparative is presented after the stimulus pair. Moreover, this equivalence cannot be attributed to the salience of the dimensions we employed, because this equivalence held for stimuli that were classified as salient and for those classified as nonsalient. These findings are interpreted in the context of some current explanations of the congruity effect.     

The semantic congruity effect: Some tests of the expectancy hypothesis

Subjects comparing items in memory along some dimension are usually quicker to specify the lesser (than the greater) of two low magnitude items and the greater (than the lesser) of two high magnitude ones. One account explains this congruity effect as due to subjects instructed to specify the higher as expecting high magnitude items to follow and the reverse being true for subjects specifying the lesser. Three experiments tested this expectancy hypothesis. In experiment 1, subjects were set to the actual size range of each pair before the pair was shown but the congruity effect still occurred. In experiments 2 and 3, subjects compared critical pairs from a narrow size range plus more from either the same or much broader ranges. Times to compare the critical pairs were the same regardless of the range of the other pairs that subjects were exposed to. These results are strong evidence against the expectancy hypothesis.     

An event-related brain potential analysis of visual word priming effects

Two experiments are reported that provide evidence on task-induced effects during visual lexical processing in a prime-target semantic priming paradigm. The research focuses on target expectancy effects by manipulating the proportion of semantically related and unrelated word pairs. In Experiment 1, a lexical decision task was used and reaction times (RTs) and event-related brain potentials (ERPs) were obtained. In Experiment 2, subjects silently read the stimuli, without any additional task demands, and ERPs were recorded. The RT and ERP results of Experiment 1 demonstrate that an expectancy mechanism contributed to the priming effect when a high proportion of related word pairs was presented. The ERP results of Experiment 2 show that in the absence of extraneous task requirements, an expectancy mechanism is not active. However, a standard ERP semantic priming effect was obtained in Experiment 2. The combined results show that priming effects due to relatedness proportion are induced by task demands and are not a standard aspect of online lexical processing.     

The locus and nature of semantic congruity in symbolic comparison: Evidence from the Stroop effect

Pictures of animals with names of animals printed within the pictures were presented for comparative judgments of size based on either the pictures or the names. The picture-word compounds were compared faster with picture than with word as the relevant dimension. The comparisons of pictures were free of interference from the irrelevant names, but the comparisons of names suffered considerable Stroop interference from the irrelevant pictures. Large effects of semantic congruity characterized the comparisons of both pictures and words. Stroop congruity and semantic congruity did not interact even for comparison of words in which both were present, leading instead to additive effects. The results support theories that (1) place semantic congruity in the decision stage and (2) minimize the role of semantic processing as the basis of the semantic congruity effect.     

Semantic congruity effects in judgments of loudness

This research uses comparative judgments of the relative loudness of sounds to make a critical test of one theory of the mental representation of continuous physical attributes. The first two experiments find a semantic congruity effect, which is an interaction such that subjects can pick the louder of two loud sounds faster than the softer, and the softer of two quiet sounds faster than the louder. According to the theory under test, physical quantities are stored as points on a representational continuum, with a variance as well as a mean placement on it. The theory predicts the semantic congruity effect by assuming that the variance of placement of intensities on the representational continuum is a function of the direction of judgment: a soft sound will have less variance than a loud one when judged for softness and more when judged for loudness. Since the speed of making a judgment increases as variance decreases, the theory predicts a semantic congruity effect. However, for loudness, it can be shown that variance does not change in the manner assumed. The finding of a semantic congruity effect therefore disconfirms the theory. Alternative models are discussed. This research was supported by NSF Grant BNS 78-17442.     

The time course of the verbal prediction effect

Choice reaction times following correct verbal predictions of the presented stimulus are faster than after incorrect predictions. Two experiments examined the influence of the time interval (PSI) between the prediction and the stimulus on the magnitude of the prediction effect. Experiment 1 used equiprobable stimuli and showed a smaller prediction effect at a 2-sec PSI than at a 0- or .5-sec PSI. Experiment 2 used unequal-probability stimuli and showed that the prediction effect was independent of PSI when the more frequent stimulus was predicted. When the less frequent stimulus was predicted, however, the magnitude of the prediction effect was smaller at .75- and 2-sec PSIs than at a 0-sec PSI. These results were discussed in terms of a prediction substitution hypothesis.     

Evidencefor implicitscaling in comparative judgment

In two experiments, we examined the effects of manipulating the density of stimuli on comparison difficulty in a comparative judgment task. In Experiment 1, subjects were slower at judging the relative size of a pair when the members were adjacent items in the linear order than when the members were separated by items of intervening magnitudes. In Experiment 2, the advantage of choosing the larger rather than the smaller of two large-stimuli (e.g., the congruity effect) increased when the linear order included many small items. In contrast, the advantage of choosing the smaller of two small items increased when the linear order included many large items. The applicability of the range-frequency theory (Parducci,1965) to these results is discussed.     

Processes underlying dimensional interactions: Correspondences between linguistic and nonlinguistic dimensions

In six experiments, we examined speeded classification when one dimension was linguistic and the other was nonlinguistic. In five of these, attributes on the dimensions corresponded meaningfully, having in common the concepts "high" and "low." For example, in Experiment 1, the visually presented words HI and LO were paired with high- or low-pitched tones; in Experiment 2, the dimensions were visual words and vertical position, in Experiment 3, they were spoken words and position, and in Experiments 4 and 5, spoken words and pitch. For each dimension in each pair, subjects suffered Garner interference when dimensions were varied orthogonally. Garner interference remained constant across 15 blocks of trials (Experiment 5). Subjects also showed significant congruity effects in all experiments, with attributes from congruent stimuli (e.g., HI/high pitch) classified faster than attributes from incongruent stimuli (e.g., HI/low pitch). These results differ from those obtained previously with noncorresponding pairs of linguistic-nonlinguistic dimensions. The results also differ from those obtained with traditional Stroop dimensions (colors and color words; Experiment 6), which showed minimal Garner interference and diminishing congruity effects across blocks of trials. We conclude that the interactions found here represent cross-talk between channels within a semantic level of processing. We contrast our view with current models of dimensional interaction.     

Is an ant larger than a lion?

In order to examine the influence exerted by an irrelevant semantic variable in a comparative judgment task, we employed a Stroop-like paradigm. The stimuli were pairs of animal names that were different in their physical and semantic sizes (e.g., ant lion). Participants were asked to judge which of the two words was larger either in physical or in semantic size. Size congruity effect (i.e., faster reaction times with congruent than with incongruent stimuli) appeared in both semantic and physical judgments. The semantic distance effect (i.e., large semantic distances are processed faster than smaller ones), appeared only when the semantic dimension was relevant to the task. The findings indicate that when a word (animal name) is presented, its meaning is accessed automatically. Part of this meaning (at least with our stimuli) relates to the size of the animal in real life. Processing of meaning of the size of the words is carried out in parallel with the extraction of the physical features of the presented stimuli.     

Dimensional interaction between color and pitch

In three experiments I investigated the nature of cross-modal dimensional interaction by testing speeded classification of the synesthetically corresponding dimensions of color (white-black) and pitch (high-low). Experiment 1 showed significant Garner interference when these dimensions were varied orthogonally--redundancy gain for positively correlated dimensions and redundancy loss for negatively correlated dimensions. Attributes from synesthetically congruent stimuli were classified faster than attributes from incongruent stimuli (a congruity effect). Experiment 2 tested a perceptual explanation of this interaction (i.e., that color and pitch are configural dimensions) by using Pomerantz's (1986) diagnostic (comparison of selective and divided attention performance). The configurality hypothesis received little support. Experiment 3 examined the effect of optional processes on color and pitch classification. The results suggest that partly strategic and partly mandatory components may constitute overall performance. Three alternative explanations of the color-pitch interaction--perceptual, semantic, and response based--are evaluated in the context of the present results.     

The Mechanism Underlying Backward Priming in a Lexical Decision Task: Spreading Activation versus Semantic Matching

Koriat (1981) demonstrated that an association from the target to a preceding prime, in the absence of an association from the prime to the target, facilitates lexical decision and referred to this effect as 'backward priming'. Backward priming is of relevance, because it can provide information about the mechanism underlying semantic priming effects. Following Neely (1991), we distinguish three mechanisms of priming: spreading activation, expectancy, and semantic matching/ integration. The goal was to determine which of these mechanisms causes backward priming, by assessing effects of backward priming on a language-relevant ERP component, the N400, and reaction time (R T). Based on previous work, we propose that the N400 priming effect reflects expectancy and semantic matching/ integration, but in contrast with R T does not reflect spreading activation. Experiment 1 shows a backward priming effect that is qualitatively similar for the N400 and R T in a lexical decision task. This effect was not modulated by an ISI manipulation. Experiment 2 clarifies that the N400 backward priming effect reflects genuine changes in N400 amplitude and cannot be ascribed to other factors. We will argue that these backward priming effects cannot be due to expectancy but are best accounted for in terms of semantic matching/ integration.     

Mental comparison of size and magnitude: size congruity effects

Paivio (1975) found that the latency to choose the larger of two named objects does not depend on congruity between the object sizes and the sizes of the object names. Because size congruity does affect latencies for pictorially presented objects, Paivio interpreted this result as support for the dual coding hypothesis. However, Experiment 1 demonstrated that Paivio's results were an artifact of his experimental design. Size congruity does affect latencies to choose the larger of two named objects when object pairs are not repeated. When the same object pairs are used repeatedly, as in Paivio's experiment, the effect disappears. In this case the response is probably remembered, so that the objects need not be compared. To determine the processing stages affected by size congruity, both the distance between stimulus sizes and the size congruity were manipulated in Experiment 2. Three groups of subjects chose either the greater Arabic digit, the greater named digit, or the larger named object. Size congruity interacted with distance only for Arabic digits. For both Arabic digits and named digits, the interference caused by size incongruity was greater than the facilitation caused by size congruity, whereas for object names, the facilitation was greater than the interference. A model of the interaction between physical size comparisons and conceptual size comparisons is proposed to account for these results.     

Arabic digit naming speed: task context and redundancy gain

There is evidence for both semantic and asemantic routes for naming Arabic digits, but neuropsychological dissociations suggest that number-fact retrieval (2x3=6) can inhibit the semantic route for digit naming. Here, we tested the hypothesis that such inhibition should slow digit naming, based on the principle that reduced access to multiple routes would counteract redundancy gain (the response time advantage expected from parallel retrieval pathways). Participants named two single digit numbers and then performed simple addition or magnitude comparison (Experiment 1), multiplication or magnitude comparison (Experiment 2), and multiplication or subtraction (Experiment 3) on the same or on a different pair of digits. Addition and multiplication were expected to inhibit the semantic route, whereas comparison and subtraction should enable the semantic route. Digit naming time was approximately 15ms slower when participants subsequently performed addition or multiplication relative to comparison or subtraction, regardless of whether or not the same digit pair was involved. A letter naming control condition in Experiment 3 demonstrated that the effect was specific to digit naming. Number fact retrieval apparently can inhibit Arabic digit naming processes.     

Is three greater than five: The relation between physical and semantic size in comparison tasks

In this study, subjects were asked to judge which of two digits (e.g., 3 5) was larger either in physical or in numerical size. Reaction times were facilitated when the irrelevant dimension was congruent with the relevant dimension and were inhibited when the two were incongruent (size congruity effect). Although judgments based on physical size were faster, their speed was affected by the numerical distance between the members of the digit pair, indicating that numerical distance is automatically computed even when it is irrelevant to the comparative judgment being required by the task. This finding argues for parallel processing of physical and semantic information in this task.