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.     

The bigram trough hypothesis and the syllable number effect in lexical decision

There has been an increasing volume of evidence supporting the role of the syllable in various word processing tasks. It has, however, been suggested that syllable effects may be caused by orthographic redundancy. In particular, it has been proposed that the presence of bigram troughs at syllable boundaries cause what are seen as syllable effects. We investigated the bigram trough hypothesis as an explanation of the number of syllables effect for lexical decision in five-letter words and nonwords from the British Lexicon Project. The number of syllables made a significant contribution to prediction of lexical decision times along with word frequency and orthographic similarity. The presence of a bigram trough did not. For nonwords, the number of syllables made a significant contribution to prediction of lexical decision times only for nonwords with relatively long decision times. The presence of a bigram trough made no contribution. The evidence presented suggests that the bigram trough cannot be an explanation of the syllable number effect in lexical decision. A comparison of the results from words and nonwords is interpreted as providing some support for dual-route models of reading.     

Word-fragment cuing: the lexical search hypothesis

In four experiments we evaluated aspects of the hypothesis that word-fragment completion depends on the results of lexical but not semantic search. Experiment 1 showed that the number of meaningful associates linked to a studied word does not affect its recovery when the test cue consists of letters and spaces for missing letters. Experiments 2 and 3 showed retroactive interference effects in fragment completion when words in a second list were lexically related to words in a first list but not when the words in the second list were meaningfully related. Experiment 4 indicated that for studied words, instructions to search at the word level facilitated completion performance and that instructions to generate letters to fill missing spaces had no effect. Other findings indicated that completion was affected by the number of words lexically related to the fragment and by the number of letters missing from the fragment. In general, experimental manipulations that focused on lexical characteristics were effective, and those that focused on semantic characteristics were ineffective. The findings support the conclusion that word fragments engender a lexical search process that does not depend on retrieving encoded meaning.     

The false consensus effect: A meta-analysis of 115 hypothesis tests

False consensus refers to an egocentric bias that occurs when people estimate consensus for their own behaviors. Specifically, the false consensus hypothesis holds that people who engage in a given behavior will estimate that behavior to be more common than it is estimated to be by people who engage in alternative behaviors. A meta-analysis was conducted upon 115 tests of this hypothesis. The combined effects of the tests of the false consensus hypothesis were highly statistically significant and of moderate magnitude. Further, the 115 tests of false consensus appear to be relatively heterogeneous in terms of significance levels and effect sizes. Correlational analyses and focused comparisons indicate that the false consensus effect does not appear to be influenced by the generality of the reference population, nor by the difference between alternative choices in actual consensus. However, the significance and magnitude of the false consensus effect was significantly predicted by the number of behavioral choices/estimates subjects had to make, and the sequence of measurement of choices and estimates. These patterns of results are interpreted as being inconsistent with the self-presentational, motivational explanation for the false consensus effect.     

Serial mechanisms in lexical access: the rank hypothesis

There is general agreement that the effect of frequency on lexical access time is roughly logarithmic, although little attention has been given to the reason for this. The authors argue that models of lexical access that incorporate a frequency-ordered serial comparison or verification procedure provide an account of this effect and predict that the underlying function directly relates access time to the rank order of words in a frequency-ordered set. For both group data and individual data, it is shown that rank provides a better fit to the data than does a function based on log frequency. Extensions to a search model are proposed that account for error rates and latencies and the effect of age of acquisition, which is interpreted as an effect of cumulative frequency.     

Design controversies and the generation effect: Support for an item-order hypothesis

We performed three experiments to investigate an earlier finding of Nairne, Riegler, and Serra (1991) that item generation disrupts the long-term retention of serial order. Experiment 1 demonstrated a clear advantage of reading over generating on a reconstruction test when reading and generating occurred in pure, but not mixed, lists. Experiment 2 showed that the standard generate advantage is seen in free recall of mixed, but not pure, lists, even when recall is immediately followed by reconstruction of serial order of the same items. Experiment 3 replicated Experiment 1, but with the use of an incidental learning procedure. The results of all three experiments are consistent with the claim that generation has dissociative effects on item and order memory; moreover, these dissociative effects help to explain design controversies-in the -generation effect literature.     

Evidence for an activation locus of the word-frequency effect in lexical decision

The authors report a lexical decision experiment designed to determine whether activation is the locus of the word-frequency effect. K. R. Paap and L. S. Johansen (1994) reported that word frequency did not affect lexical decisions when exposure durations were brief; they accounted for this by proposing that data-limited conditions prevented late-occurring verification processes. Subsequently, P. A. Allen, A. F. Smith, M. Lien, T. A. Weber, and D. J. Madden (1997) and K. R. Paap, L. S. Johansen, E. Chun, and P. Vonnahme (2000) reported additional evidence that word-frequency effects do and do not have an activation locus, respectively. The authors further tested this issue in a lexical decision experiment using data-limited procedures--predicted by verification models to eliminate word-frequency effects. The authors observed word-frequency effects using individually determined exposure durations that were only 1 screen cycle longer than the exposure duration that yielded chance performance. Word-frequency effects persisted even when an adjusted measure of performance was used.     

Naming regular and exception words: Further examination of the effect of phonological dissension among lexical neighbours

Abstract

It is generally assumed that visual word recognition is accompanied by the activation of lexical representations corresponding to words orthographically similar to the target (neighbours). With regard to the pronunciation of their constituent units, these words can either converge with or diverge from the target pronunciation. The role of the frequency of the divergent pronunciations in print-to-sound conversion was examined in a naming experiment in which subjects pronounced regular and exception words. The results showed that naming latencies for exception words were affected by the orthographic similarity of the target with frequent phonologically divergent words (enemies). In a similar vein, regular words which include the letters G or C (whose pronunciations are contextually determined) and which are orthographically similar to words favouring an incorrect pronunciation of the letter took longer to pronounce than regular controls. A delayed naming experiment indicated that these differences were not attributable to the articulatory characteristics of the items. Finally, it also appeared that enemy frequency influenced naming latencies but not regularisation rates and regularisation latencies. The results are discussed within the framework of current dual-route and parallel distributed processing models of reading.     

Reading aloud: The cumulative lexical interference effect

Picture naming shows a cumulative semantic interference effect: Latency for naming a target picture increases as a function of the number of pictures semantically similar to the target that have previously been named (Howard, Nickels, Coltheart, & Cole-Virtue, Cognition 100:464-482, 2006). Howard and colleagues, and also Oppenheim, Dell, and Schwartz (Cognition 114:227-252, 2010), argued that this occurs because of the joint presence in the picture-naming system of three critical properties: shared activation, priming, and competition. They also discussed the possibility that whenever any cognitive system possesses these three properties, a cumulative similarity-based interference effect from repeated use of that cognitive system will occur. We investigated this possibility by looking for a cumulative lexical interference effect when the task is reading aloud: Will the latency of reading a target word aloud increase as a function of the number of words orthographically/phonologically similar to the target that have previously been read aloud? We found that this was so. This supports the general idea that cumulative similarity-based interference effects will arise whenever any cognitive system that possesses the three key properties of shared activation, priming, and competition is repeatedly used.     

The verbal transformation effect: auditory illusions as an index of lexical processing and homolog activation.

A technique of inducing auditory illusions was used so that 192 undergraduates heard through headphones either three asynchronous dichotic versions of the same repeating word, at each of three auditory locations (left, center, and right), or only one single repeating word, monaurally or diotically, at each location. Independent illusory changes at each location were reported. Subjects' reports of lexical illusions, but not nonlexical illusions, were fewer at the right ear for three- vs. one-signal listening. These results support the homolog activation hypothesis (Boles, 1990) in which disruption of interhemispheric communication occurs for the hemisphere least capable of processing lexical information. In the current experiment homolog activation led to loss of lexical information when received from auditory positions other than the right, when three signals are presented. Lexical illusions (Verbal Transformations) may be the result of the misapplication of lexical knowledge in an ambiguous situation, listening to a recycling word without stabilizing syntactic or semantic context.     

Changes in brain activation induced by the training of hypothesis generation skills: an fMRI study

The aim of the present study is to investigate the learning-related changes in brain activation induced by the training of hypothesis generation skills regarding biological phenomena. Eighteen undergraduate participants were scanned twice with functional magnetic resonance imaging (fMRI) before and after training over a period of 2 months. The experimental group underwent eight biological hypothesis generation training programs, but the control group was not given any during the 2-month period. The results showed that the left frontal gyri, the cingulate gyrus, and the cuneus were activated during hypothesis generation. In addition, the brain activation of the trained group increased in the left inferior and the superior frontal gyri, which are related to working memory load and higher-order inferential processes. However, the activation after training decreased in the occipito-parietal route, which is associated with the perception and the analysis processes of visual information. Furthermore, the results have suggested that the dorsolateral prefrontal cortex (DLPFC) region is the critical area in the training of hypothesis generation skills.     

Further study of the electrophysiological correlates of lexical decision

Discriminations were required between words, pseudohomophones, and visually matched nonwords. Two tasks were employed, one which could be accomplished on the basis of a visual code (the REAL task, involving discrimination between words and both types of nonword) and another necessitating the use of a phonological code (the REAL/PSEUD task, words and pseudohomophones vs. nonwords). ERPs were recorded from three midline sites and from left and right inferior parietal sites. Two principal results were observed, (i) the peak latency of a late positive component, P637, covaried with RT, with variations in latency of around one half the corresponding RT variations, and (ii) the peak-to-peak amplitude of N100-P187 interacted with stimulus and task, such that it was larger for nonwords in the REAL task and words in the REAL/PSEUD task. No taskor stimulus-dependent asymmetries were observed in any ERP component. The P637 latency data support a model of RT variation based on the interaction of changes in parallel response preparation and stimulus evaluation processes. The observations with respect to N100-P187 suggest that ERPs are sensitive to factors related to the early processing of words and word-like visual material.     

Direct versus indirect tests of memory: Directed forgetting meets the generation effect

Subjects read 20 words and generated 20 others from definitions during a 40-item study phase. Production of each word was followed by an instruction to remember or to forget that word. In free recall, a direct test of memory, words that had been generated were recalled much better than words that had been read. The remember-forget instructional manipulation affected read words but not generated words. In speeded word reading, an indirect test of memory, all studied words showed priming, but read words showed more priming than generated words. Here, the effect of remember versus forget instructions appeared only for generated words. These dissociations of a direct and an indirect test indicate that two powerful encoding manipulations affect separable processes to which these tests are differentially sensitive.     

Two tests of the stuck-in-time hypothesis

The authors report 2 experiments that test the stuck-in-time hypothesis, which argues that animals cannot time-date events and thus do not remember when events occurred and do not anticipate future events. In Experiment 1, rats in the experimental condition could earn a large reward by reentering the 1st arm that they visited on a radial maze. They did not learn to reenter this arm early and did no better than did a control group that was not given a large reward for reentering the first arm. In Experiment 2, rats in the experimental group could earn a large reward by delaying entry into a distinctive arm. These rats did not learn to delay entry into the distinctive arm, and they performed no better than did the control-group rats, which did not receive a large reward for delayed entry. These experiments provide further evidence in support of the stuck-in-time hypothesis.     

The precise time course of lexical activation: MEG measurements of the effects of frequency, probability, and density in lexical decision

Visually presented letter strings consistently yield three MEG response components: the M170, associated with letter-string processing (Tarkiainen, Helenius, Hansen, Cornelissen, & Salmelin, 1999); the M250, affected by phonotactic probability, (Pylkk?nen, Stringfellow, & Marantz, 2002); and the M350, responsive to lexical frequency (Embick, Hackl, Schaeffer, Kelepir, & Marantz, 2001). Pylkk?nen et al. found evidence that the M350 reflects lexical activation prior to competition among phonologically similar words. We investigate the effects of lexical and sublexical frequency and neighborhood density on the M250 and M350 through orthogonal manipulation of phonotactic probability, density, and frequency. The results confirm that probability but not density affects the latency of the M250 and M350; however, an interaction between probability and density on M350 latencies suggests an earlier influence of neighborhoods than previously reported.     

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.