On the nonautomaticity of visual word processing: electrophysiological evidence that word processing requires central attention

The present study used event-related potentials (ERPs) to determine the degree to which people can process words while devoting central attention to another task. Experiments 1-4 measured the N400 effect, which is sensitive to the degree of mismatch between a word and the current semantic context. Experiment 5 measured the P3 difference between low- and high-frequency words. Because these effects can occur only if a word has been identified, both ERP components index word processing. The authors found that the N400 effect (Experiments 1, 3, and 4) and the P3 difference (Experiment 5) were strongly attenuated for Task 2 words presented nearly simultaneously with Task 1. No such attenuation was found when the Task 1 stimulus was presented but required no response (Experiment 2). Strong attenuation was also evident when the Task 2 word was presented before the Task 1 stimulus (Experiment 4), suggesting that central resources are not allocated to stimuli first-come, first-served but rather are strategically locked to Task 1. The authors conclude that visual word processing is not fully automatic but rather requires access to limited central attentional resources.     

Semantic access in second-language visual word processing: Evidence from the semantic Simon paradigm

The present study investigated whether visually presented second-language words activate their meaning during low-level word processing, just as native-language words do. Using the semantic Simon paradigm (De Houwer, 1998) with a letter-case judgment task, Dutch-English bilingual participants were instructed to classify targets’ letter case using verbal labels (e.g., by saying “animal” to uppercase targets or “occupation” to lowercase targets). Results showed that both native-language and second-language targets yielded faster responses if the verbal response corresponded to the targets’ semantic category (e.g., the response “animal” to the target LEEUW or LION) than when it did not (e.g., LAWYER), even though the meaning of target words was irrelevant for the task. These results show that second-language word forms may quickly and automatically activate their meaning through strong form-to-meaning mappings, which is consistent with theories of bilingual lexicosemantic organization, such as that of Duyck and Brysbaert (2004).     

The effect of visual word features on the acquisition of orthographic knowledge

Research with adults has shown that the distortion of visual word features, and in particular of the multiletter features within words, hampers word recognition. In this study, "CaSe MiXiNg" was employed to examine the effect of disrupting visual word features on the acquisition of orthographic knowledge in children. During the training, 18 beginning and 27 advanced readers (in Grades 2, 4, and 5) repeatedly read a set of pseudowords in either lowercase or mixed case. During this training, case mixing appeared to impair reading speed in both reader groups. At posttest, 1 day after the training, case format was either the same as or different from that during the training. Lowercase pseudowords were recognized faster after a lowercase training than after a mixed-case training. In a second study, case was found not to affect the rapid naming of single letters. The combined results suggest that case mixing disrupted the multiletter features in pseudowords and that the disruption of these features can affect the acquisition of orthographic knowledge.     

The initial capitalization superiority effect in German: evidence for a perceptual frequency variant of the orthographic cue hypothesis of visual word recognition

A perceptual frequency variant of the orthographic cue (OC) hypothesis (Peressotti, Cubelli, & Job, 2003) was tested in two perceptual identification experiments using the variable viewing position technique: German nouns and non-nouns that are most frequently perceived with or without initial letter capitalization, respectively, were tachistoscopically presented in upper-case, lower-case, or with initial capitalization. The results indicated that words were best recognized in the form they are most frequently perceived in, which suggests that during reading acquisition abstract as well as case- and item-specific OCs may be learned and used for recognition.     

Phonological neighbors speed visual word processing: evidence from multiple tasks

The author investigated the role of phonological neighborhood on visual word recognition. Using a lexical decision task, the author showed in Experiment 1 that words with large phonological neighborhoods were processed more rapidly than those with smaller phonological neighborhoods. This facilitative effect was obtained even when the nonword fillers had the same number of phonological neighbors as the words. This finding indicates that phonological neighbors speed processing within the phonological system. In the next 2 experiments, this claim was further tested using the naming and semantic categorization tasks. In both experiments, the effect of phonological neighborhood was found to be facilitative. The results across all 3 experiments indicate that phonology is central to visual word recognition and that phonological neighborhood provides a reliable measure of phonological processing.     

Pathway control in visual word processing: Converging evidence from recognition memory

The extent to which readers can exert strategic control over oral reading processes is a matter of debate. According to the pathway control hypothesis, the relative contributions of the lexical and nonlexical pathways can be modulated by the characteristics of the context stimuli being read, but an alternative time criterion model is also a viable explanation of past results. In Experiment 1, subjects named high- and low-frequency regular words in the context of either low-frequency exception words (e.g., pint) or nonwords (e.g., flirp). Frequency effects (faster pronunciation latencies for high-frequency words) were attenuated in the nonword context, consistent with the notion that nonwords emphasize the characteristics of the frequency-insensitive nonlexical pathway. Importantly, we also assessed memory for targets, and a similar attenuation of the frequency effect in recognition memory was observed in the nonword condition. Converging evidence was obtained in a second experiment in which a variable that was more sensitive to the nonlexical pathway (orthographic neighborhood size) was manipulated. The results indicated that both speeded pronunciation performance and memory performance were relatively attenuated in the low-frequency exception word context in comparision with the nonword context. The opposing influences of list context type for word frequency and orthographic neighborhood size effects in speeded pronunciation and memory performance provide strong support for the pathway control model, as opposed to the time criterion model.     

Modulating semantic feedback in visual word recognition

According to the interactive activation framework proposed by McClelland and Rumelhart (1981), activation spreads both forward and backward between some levels of representation during visual word recognition. An important boundary condition, however, is that the spread of activation from lower to higher levels can be prevented (e.g., explicit letter processing during prime processing eliminates the well-documented semantic priming effect). Can the spread of activation from higher to lower levels also be prevented? This question was addressed with a choice task procedure in which subjects read a prime word and then responded to a target, performing either lexical decision or letter search depending on the color of the target. A semantic context effect was observed in lexical decision, providing evidence of semantic-level activation. In contrast, there was no semantic context effect in the letter search task, despite evidence of lexical involvement: Words were searched faster than nonwords. Further evidence of lexical involvement in the letter search task appeared in Experiment 2 in the form of greater identity priming for words than for nonwords. The results of these experiments are consistent with the conclusion that feedback from the semantic level to the lexical level can be blocked. Hence, between-level activation blocks can be instantiated in both bottom-up and top-down directions.     

Reexamining the word length effect in visual word recognition: New evidence from the English Lexicon Project

In the present study, we reexamined the effect of word length (number of letters in a word) on lexical decision. Using the English Lexicon Project, which is based on a large data set of over 40,481 words (Balota et al., 2002), we performed simultaneous multiple regression analyses on a selection of 33,006 English words (ranging from 3 to 13 letters in length). Our analyses revealed an unexpected pattern of results taking the form of a U-shaped curve. The effect of number of letters was facilitatory for words of 3–5 letters, null for words of 5–8 letters, and inhibitory for words of 8–13 letters. We also showed that printed frequency, number of syllables, and number of orthographic neighbors all made independent contributions. The length effects were replicated in a new analysis of a subset of 3,833 monomorphemic nouns (ranging from 3 to 10 letters), and also in another analysis based on 12,987 bisyllabic items (ranging from 3 to 9 letters). These effects were independent of printed frequency, number of syllables, and number of orthographic neighbors. Furthermore, we also observed robust linear inhibitory effects of number of syllables. Implications for models of visual word recognition are discussed.     

The SNARC effect in the processing of second-language number words: further evidence for strong lexico-semantic connections

We present new evidence that word translation involves semantic mediation. It has been shown that participants react faster to small numbers with their left hand and to large numbers with their right hand. This SNARC (spatial-numerical association of response codes) effect is due to the fact that in Western cultures the semantic number line is oriented from left (small) to right (large). We obtained a SNARC effect when participants had to indicate the parity of second-language (L2) number words, but not when they had to indicate whether L2 number words contained a particular sound. Crucially, the SNARC effect was also obtained in a translation verification task, indicating that this task involved the activation of number magnitude.     

The phonological-distributional coherence hypothesis: cross-linguistic evidence in language acquisition

Several phonological and prosodic properties of words have been shown to relate to differences between grammatical categories. Distributional information about grammatical categories is also a rich source in the child's language environment. In this paper we hypothesise that such cues operate in tandem for developing the child's knowledge about grammatical categories. We term this the Phonological-Distributional Coherence Hypothesis (PDCH). We tested the PDCH by analysing phonological and distributional information in distinguishing open from closed class words and nouns from verbs in four languages: English, Dutch, French, and Japanese. We found an interaction between phonological and distributional cues for all four languages indicating that when distributional cues were less reliable, phonological cues were stronger. This provides converging evidence that language is structured such that language learning benefits from the integration of information about category from contextual and sound-based sources, and that the child's language environment is less impoverished than we might suspect.     

Parallel versus serial processing in visual search: further evidence from subadditive effects of visual quality.

The authors propose a diagnostic for distinguishing between serial and parallel processing in visual search; it is based on testing for subadditive effects of a within-trial visual quality manipulation on target-absent trials. It was evaluated in 2 experiments wherein parallel and serial processing might be expected on the basis of previous work and was then applied to a more uncertain situation in a third experiment. The diagnostic indicates parallel processing of stimuli that differ from each other on a featural basis (Xs and Os) and canonical letters that differ in line arrangement (Ts and Ls) but serial processing when Ts and Ls are randomly rotated. These results form a coherent pattern that is understandable in terms of the literature on visual search, and thus they suggest that the diagnostic may be a useful addition to the methodology used to distinguish between serial and parallel processes.     

Morphological processing during visual word recognition in developing readers: evidence from masked priming

Masked priming studies with adult readers have provided evidence for a form-based morpho-orthographic segmentation mechanism that "blindly" decomposes any word with the appearance of morphological complexity. The present studies investigated whether evidence for structural morphological decomposition can be obtained with developing readers. We used a masked primed lexical decision design first adopted by Rastle, Davis, and New (2004), comparing truly suffixed (golden-GOLD) and pseudosuffixed (mother-MOTH) prime-target pairs with nonsuffixed controls (spinach-SPIN). Experiment 1 tested adult readers, showing that priming from both pseudo- and truly suffixed primes could be obtained using our own set of high-frequency word materials. Experiment 2 assessed a group of Year 3 and Year 5 children, but priming only occurred when prime and target shared a true morphological relationship, and not when the relationship was pseudomorphological. This pattern of results indicates that morpho-orthographic decomposition mechanisms do not become automatized until a relatively late stage in reading development.     

Orthographic processing in visual word identification

A series of experiments is reported examining orthographic priming effects between briefly presented pairs of letter strings. The experiments investigate the effects of the number and position of letters shared by primes and targets, and the effects of prime-target length. Priming effects increase nonlinearly as a function of both the number and the position of shared letters, and they are dependent on the positions of letters relative to both the end positions in the string and to the identities of their nearest neighbours. There is little effect of absolute string length on priming. These priming effects can be distinguished from intrusion errors where letters from primes are reported in response to targets. An account of orthographic processing is outlined which attributes priming to cooperative interactions between coarse relative-position coded letter cluster representations activated by primes and targets. The implications of the findings for understanding other effects in word recognition and reading are discussed.     

Attentional holism in visual word processing

Summary Decisions about the identity of an entire word are made more quickly than decisions about the identity of a letter within a word. Explanations of this whole-word advantage based on the time-course of the activation of different levels of unit detectors have given way to explanations based on how attention is allocated to the output of the detectors. Three studies were carried out to examine the role of attention in the whole-word advantage. In Experiment 1, cues as to the level of decision (whole-word vs. first-letter) facilitated component processing, a finding that suggests word level information is normally the focus of attention. In Experiment 2, identification of a probe item to the right of a display was longer when subjects prepared for a first-letter rather than a whole-word decision. That is, the spatial extent of attention is wider for whole-word decisions. In Experiment 3, probe latencies were longer when subjects prepared for a whole-word decision than when they prepared for a signalled probe trial. Preparation for a whole-word decision is not automatic in the sense of being free of capacity demands. The overall pattern of results leads to the conclusion that the whole-word advantage is an instance of attentional holism.     

Capacity limitations in visual word processing

The ability of subjects to process English words in a spatially parallel manner was examined in several redundant-target detection tasks. When redundant targets were identical in a given display, processing limitations were evident in a task that required subjects to make semantic categorizations of words. However, parallel processing of identical redundant target words was exhibited in a lexical decision task that required a structural analysis of letter strings, but not an analysis of word meaning. The difference in performance in the two tasks suggests that the capacity for semantic processing is limited. Analyses designed to examine whether the redundancy gain in Experiment 2 could be attributed to limited capacity processing in conjunction with positional preferences provided evidence against this possibility. In addition, these analyses suggested that the processing times for the redundant targets in Experiment 2 might be positively correlated. In the third and fourth experiments, the redundant-target displays contained two different words. Processing interference, in the form of a redundancy loss, was evident in the lexical decision task, but not in the semantic categorization task, confirming a difference in the mode of processing between the two tasks. The results provide evidence against the unlimited-capacity, parallel processing hypothesis of late selection theories of attention.     

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.     

Dissociating word frequency and age of acquisition: The Klein effect revived (and reversed)

The Klein effect (G. S. Klein, 1964) refers to the finding that high-frequency words produce greater interference in a color-naming task than low-frequency words. The present study used the Klein effect to investigate the relationship between frequency and age of acquisition (AoA) by measuring their influence on color naming. Two experiments showed reliable effects of frequency (though in the opposite direction to that reported by Klein) but no effects of AoA. Experiment 1 produced a dissociation between frequency and AoA when manipulated orthogonally. Experiment 2 produced the same dissociation using different stimuli. In contrast, both variables reliably influenced word naming. These findings are inconsistent with the view that frequency and AoA are 2 aspects of a single underlying mechanism.     

The distinct contributions of age of acquisition and word frequency in auditory word perception

We report two studies of the distinct effects that a word's age of acquisition (AoA) and frequency have on the mental lexicon. In the first study, a purely statistical analysis, we show that AoA and frequency are related in different ways to the phonological form and imageability of different words. In the second study, three groups of participants (34 seven-year-olds, 30 ten-year-olds, and 17 adults) took part in an auditory lexical decision task, with stimuli varying in AoA, frequency, length, neighbourhood density, and imageability. The principal result is that the influence of these different variables changes as a function of AoA: Neighbourhood density effects are apparent for early and late AoA words, but not for intermediate AoA, whereas imageability effects are apparent for intermediate AoA words but not for early or late AoA. These results are discussed from the perspective that AoA affects a word's representation, but frequency affects processing biases.     

The distinct contributions of age of acquisition and word frequency in auditory word perception

We report two studies of the distinct effects that a word's age of acquisition (AoA) and frequency have on the mental lexicon. In the first study, a purely statistical analysis, we show that AoA and frequency are related in different ways to the phonological form and imageability of different words. In the second study, three groups of participants (34 seven-year-olds, 30 ten-year-olds, and 17 adults) took part in an auditory lexical decision task, with stimuli varying in AoA, frequency, length, neighbourhood density, and imageability. The principal result is that the influence of these different variables changes as a function of AoA: Neighbourhood density effects are apparent for early and late AoA words, but not for intermediate AoA, whereas imageability effects are apparent for intermediate AoA words but not for early or late AoA. These results are discussed from the perspective that AoA affects a word's representation, but frequency affects processing biases.