Speed of lexical and nonlexical processing in French: The case of the regularity effect

Words with irregular spelling-sound correspondences are read aloud more slowly than words with regular spelling-sound correspondences. This so-calledregularity effect is modulated by word frequency, with low-frequency words showing larger costs than do high-frequency words. Because French has more regular spelling-to-sound correspondences than English, we expected a different pattern in French than in English. This was indeed the case, since regularity effects were obtained for both high-and low-frequency words in French. We further showed that a French implementation of the dual-route cascaded model could not account for this pattern. In additional simulations, we investigated whether this failure was due to lexical processes being too fast (leaving little time for the nonlexical route to interfere) or nonlexical processes being too slow. The results showed that only speeding up the nonlexical route allowed the model to capture the data. This suggests that the delayed phonology assumption that characterizes nonlexical processing in the original model needs to be abandoned in a more regular orthography.     

Experimental evidence for differential slowing in the lexical and nonlexical domains

Abstract

Older and younger adults were tested on lexical and nonlexical tasks. When lexical and nonlexical processing were compared across equivalent ranges of task complexity, the degree of age-related slowing in the nonlexical domain was much larger than that observed in the lexical domain. to determine whether this nonlexical disadvantage is specific to older adults or whether it is characteristic of any slow individual, subgroups of fast older and slow young adults were matched on lexical processing speed. Older adults who were fast processors of lexical information were much slower at processing nonlexical information, but this was not true of slow young adults for whom the speed of processing lexical and nonlexical information was equivalent.     

Written spelling to dictation: Sound-to-spelling regularity affects both writing latencies and durations

The authors examined the effect of sound-to-spelling regularity on written spelling latencies and writing durations in a dictation task in which participants had to write each target word 3 times in succession. The authors found that irregular words (i.e., those containing low-probability phoneme-to-grapheme mappings) were slower both to initially produce and to execute in writing than were regular words. The regularity effect was found both when participants could and could not see their writing (Experiments 1 and 2) and was larger for low- than for high-frequency words (Experiment 3). These results suggest that central processing of the conflict generated by lexically specific and assembled spelling information for irregular words is not entirely resolved when the more peripheral processes controlling handwriting begin.     

An examination of age-related changes in the control of lexical and sublexical pathways in mapping spelling to sound

The current study investigated the extent to which young and older adults are able to direct attention to distinct processes in mapping spelling onto sound. Young and older adults completed either a speeded pronunciation task (reading aloud words) or regularization task (pronouncing words based on spelling-to-sound correspondences, e.g., pronouncing PINT such that it rhymes with HINT) in order to bias processing of lexical, whole-word information, or sublexical, spelling-to-sound mapping, respectively. Both younger and older adults produced reduced word-frequency effects and lexicality effects in the regularization task compared to the normal pronunciation task. Importantly, compared to younger adults, older adults produced exaggerated effects of task (i.e., pronunciation vs. regularization) on the observed frequency and lexicality effects. These results highlight both the flexibility of the lexical processing system and changes in the influence of the underlying lexical route due to additional 50 years of reading experience and/or changes in attentional control.     

Phonological and working memory mechanisms involved in written spelling

Recent theories of spelling based on neuropsychological data and on computational modelling (Caramazza & Miceli, 1990; Caramazza, Miceli, Villa, & Romani, 1987; Glasspool & Houghton, 2005; Glasspool, Shallice, & Cipolotti, 2006; Miceli & Capasso, 2006; Rapp & Kong, 2002) assume that a working memory system is used to store identity and order of the graphemes, and propose that an impairment of this system, called Graphemic Buffer (GB), is marked by the presence of a number of typical effects. Recently, this disorder has been simulated by different versions of the Competitive Queuing model (Glasspool & Houghton, 2005; Glasspool et al., 2006). The effect of the disruption of this mechanism in written spelling was investigated by means of a dual task in the present study. Three-syllable and four-syllable words were presented to normal adults for aural presentation (Experiment 1) and spelling by copying (Experiment 2). In order to investigate the effects of dual tasks, and the possible involvement of phonological codes, three conditions were used: simple dictation, concurrent articulation, and foot tapping. The results showed strong effects of concurrent articulation, and were consistent with the hypothesis that this task disrupted the serial operations of readout and sequential planning of the GB. They were also consistent with the simulations of the Competitive Queuing model, suggesting possible loci of the effects.     

Hemispheric processing characteristics for lexical decisions in adults with reading disorders

The present study measured unilateral tachistoscopic vocal reaction times and error responses of reading-disordered and normally reading adults to single words and nonwords in a series of lexical decision tasks at two linguistic levels (concrete and abstract words). Analysis of variance on reaction times indicated that main effects of stimulus type, visual field, and the interaction of these variables were not significant for the reading-disordered group, but visual field and an interaction of visual field and stimulus type were for the normally reading adults. Error rate showed a significant interaction of stimulus x visual field for the reading-disordered group but not for the normal reading group. Post hoc tests showed significant differences in error rates between visual fields for concrete lexicon but not for abstract or nonsense lexicon for the reading-disordered group. These findings suggest a deficit in interhemispheric lexical transfer occurs for reading-disordered samples and suggest use of a callosal relay model wherein the left hemisphere is allocated responsibility for performing central operations underlying lexical decisions by adults with reading disorders.     

Effects of induced emotional state on lexical processing in younger and older adults

The authors investigated the effects of an induced emotional mood state on lexical decision task (LDT) performance in 50 young adults and 25 older adults. Participants were randomly assigned to either happy or sad mood induction conditions. An emotional mood state was induced by having the participants listen to 8 min of classical music previously rated to induce happy or sad moods. Results replicated previous studies with young adults (i.e., sad-induced individuals responded faster to sad words and happy-induced individuals responded faster to happy words) and extended this pattern to older adults. Results are discussed with regard to information processing, aging, and emotion.     

The oral and written side of word production in young and older adults: generation of lexical neighbors

The aim of the present study was to investigate the effects of aging on both spoken and written word production by using analogous tasks. To do so, a phonological neighbor generation task (Experiment 1) and an orthographic neighbor generation task (Experiment 2) were designed. In both tasks, young and older participants were given a word and had to generate as many words as they could think of by changing one phoneme in the target word (Experiment 1) or one letter in the target word (Experiment 2). The data of the two experiments were consistent, showing that the older adults generated fewer lexical neighbors and made more errors than the young adults. For both groups, the number of words produced, as well as their lexical frequency, decreased as a function of time. These data strongly support the assumption of a symmetrical age-related decline in the transmission of activation within the phonological and orthographic systems.     

Error self-correction and spelling: improving the spelling accuracy of secondary students with disabilities in written expression

In order to improve the spelling performance of high school students with deficits in written expression, an error self-correction procedure was implemented. The participants were two tenth-grade students and one twelfth-grade student in a program for individuals with learning disabilities. Using an alternating treatments design, the effect of error self-correction was compared with a more traditional method of spelling practice. The intervention and follow-up phases were implemented over a 6-week period with maintenance checks conducted 4 and 8 weeks after the termination of instruction. Results indicated that the error self-correction procedure was superior to the traditional method of review during the intervention and follow-up phases, but some gains were lost during the maintenance phase.     

Deafness, spelling and rhyme: How spelling supports written word and picture rhyming skills in deaf subjects

Orally trained, congenitally deaf adolescents and hearing, reading-age-matched control subjects made rhyme judgements for pictures and for written words. Hearing children performed the task accurately. By contrast, the deaf group were very poor at rhyme judgement for words and for pictures. For hearing children, word rhyme judgement was more accurate when the words were congruent in their spelling pattern (e.g. bat/hat), less accurate when the spelling pattern of the rhyming words was incongruent (hair/bear). Deaf subjects showed an even more pronounced effect of spelling congruence; their ability to match for rhyme when written words did not share the same spelling pattern was extremely poor. Moreover, spelling congruence predicted deaf subjects' picture rhyming skills.

We conclude that oral training for deaf people does not always permit them to achieve a reliable phonological representation of speech from lip-reading and residual hearing alone. Instead they use the written spelling of the word. This result is not predicted from some previous results that suggest that orally trained deaf people can make direct, spontaneous use of rhyme in the processing of visually presented material.     

Contextual control over lexical and sublexical routines when reading English aloud

Are the processes responsible for reading aloud single well-formed letter strings under contextual control? Despite the widespread contention that the answer to this question is “yes,” it has been remarkably difficult to provide a compelling demonstration to that effect. In a speeded naming experiment, skilled readers read aloud exception words (such asPint) that are atypical in terms of their spelling sound correspondences and nonwords (such asFlad) that appeared in a predictable sequence. Subjects took longer to name both words and nonwords when the item on the preceding trial was from the other lexical category, relative to when the preceding item was from the same lexical category. This finding is consistent with the relative contributions of lexical and sublexical knowledge being controlled. We note a number of different ways that this control could arise and suggest some directions for future research.     

Phonological processing and lexical access in aphasia

This study explored the relationship between on-line processing of phonological information and lexical access in aphasic patients. A lexical decision paradigm was used in which subjects were presented auditorily with pairs of words or word-like stimuli and were asked to make a lexical decision about the second stimulus in the pair. The initial phonemes of the first word primes, which were semantically related to the real word targets, were systematically changed by one or more than one phonetic feature, e.g., cat-dog, gat-dog, wat-dog. Each of these priming conditions was compared to an unrelated word baseline condition, e.g., nurse-dog. Previous work with normals showed that even a nonword stimulus receives a lexical interpretation if it shares a sufficient number of phonetic features with an actual word in the listener's lexicon. Results indicated a monotonically decreasing degree of facilitation as a function of phonological distortion. In contrast, fluent aphasics showed priming in all phonological distortion conditions relative to the unrelated word baseline. Nonfluent aphasics showed priming only in the undistorted, related word condition relative to the unrelated word baseline. Nevertheless, in a secondary task requiring patients to make a lexical decision on the nonword primes presented singly, all aphasics showed phonological feature sensitivity. These results suggest deficits for aphasic patients in the various processes contributing to lexical access, rather than impairments at the level of lexical organization or phonological organization.     

Developmental phonological and lexical agraphia in adults

Many cases of agraphia from acquired cerebral lesions may be divided into two groups, phonological and lexical, suggesting two dissociable spelling systems. Studies of developmental agraphia have described some children who have spelling patterns similar to acquired phonological or lexical agraphia. This study analyzed spelling results from 22 adolescent and adult subjects with developmental agraphia (DA) and compared them to those from control subjects and subjects with acquired agraphia (AA). On the basis of spelling ability, subjects with DA could be divided into two groups. Analysis of the profile of spelling abilities indicated that the two groups of subjects with DA were almost indistinguishable from the two groups of subjects with AA, phonological and lexical. This supports the contention that DA in adults may be divided into phonological and lexical groups and further supports the two-system hypothesis for linguistic agraphia.     

Attentional resource demands of visual word recognition in naming and lexical decisions.

Attentional demands of lexical access were assessed with dual-task methodology. Subjects performed an auditory probe task alone (single-task) or combined (dual-task) with either a lexical decision or a naming task. In Experiment 1, probe performance showed a decrement from single- to dual-task conditions during recognition of words in both lexical decision and naming tasks. In addition, decrements in probe performance were larger during processing of low-frequency compared with high-frequency words in both of the word recognition tasks. Experiment 2 showed that the time course of frequency-sensitive demands was similar across lexical decision and naming tasks and that attention is required early in the word recognition sequence. The results support the assumption that lexical access is both frequency sensitive and attention demanding.     

Context processing and cognitive control in children and young adults

T. S. Braver and colleagues (e.g., T. S. Braver, J. D. Cohen, & D. M. Barch, 2002) have provided a theory of cognitive control that focuses on the role of context processing. According to their theory, an underlying context-processing mechanism is responsible for the cognitive control functions of attention, inhibition, and working memory. In the present study, the authors examined whether T. S. Braver et al.'s theory can account for developmental differences in cognitive control. The authors compared the performance of children (M age = 11.9 years, SD = 0.43 years) with that of young adults (M age = 21.7 years, SD = 3.61 years) on a continuous performance task (AX-CPT) that placed demands on context processing. The results suggest that developmental differences in the cognitive control functions of attention, inhibition, and working memory may be based on age-related changes in an underlying context-processing mechanism.     

Preserved orthographic length and transitional probabilities in written spelling in a case of acquired dysgraphia

We present the performance of a patient with acquired dysgraphia, DS, who has intact oral spelling (100% correct) but severely impaired written spelling (7% correct). Her errors consisted entirely of well-formed letter substitutions. This striking dissociation is further characterized by consistent preservation of orthographic, as opposed to phonological, length in her written output. This pattern of performance indicates that DS has intact graphemic representations, and that her errors are due to a deficit in letter shape assignment. We further interpret the occurrence of a small percentage of lexical errors in her written responses and a significant effect of letter frequencies and transitional probabilities on the pattern of letter substitutions as the result of a repair mechanism that locally constrains DS' written output.     

Attentional resource and processing speed limitations during sentence processing in Parkinson's disease

Several studies have suggested that patients with Parkinson's disease (PD) have sentence comprehension difficulty in part because of their limited executive resources. However, these assessments confound the executive resources contributing to sentence comprehension with the resources needed for task performance. In the present study, we used a word detection technique that minimizes task demands in order to evaluate attentional and processing speed resources during the comprehension of simple sentences without subordinate clauses and sentences containing subject-relative and object-relative center-embedded subordinate clauses. We found that PD patients have poor sensitivity to phonetic errors embedded in unbound grammatical morphemes, regardless of the clausal structure of the sentence, suggesting difficulty attending to grammatical morphemes. We also found that PD patients are significantly slowed in their sensitivity to phonetic errors in content words embedded in object-relative center-embedded sentences. Slowed sensitivity to content words in object-relative sentences was correlated with timed executive measures of planning. On a traditional measure of comprehension, these PD patients were impaired for sentences containing object-relative center-embedded clauses compared to sentences with subject-relative center-embedded clauses, and comprehension of object-relative sentences was correlated with executive measures. Our findings are consistent with the claim that limited executive resources for strategic attention and processing speed contribute to the sentence comprehension difficulties of PD patients.     

Determinants of spelling ability in deaf and hearing adults: Access to linguistic structure

The extent to which ability to access linguistic regularities of the orthography is dependent on spoken language was investigated in a two-part spelling test administered to both hearing and profoundly deaf college students. The spelling test examined ability to spell words varying in the degree to which their correct orthographic representation could be derived from the linguistic structure of English. Both groups of subjects were found to be sensitive to the underlying regularities of the orthography as indicated by greater accuracy on linguistically-derivable words than on irregular words. Comparison of accuracy on a production task and on a multiple-choice recognition task showed that the performance of both deaf and hearing subjects benefited from the recognition format, but especially so in the spelling of irregular words. Differences in the underlying spelling process for deaf and hearing spellers were revealed in an analysis of their misspellings: Deaf subjects produced fewer phonetically accurate misspellings than did the hearing subjects. Nonetheless, the deaf spellers tended to observe the formational constraints of English phonology and morphology in their misspellings. Together, these results suggest that deaf subjects are able to develop an appreciation for the structural properties of the orthography, but that their spelling may be guided by an accurate representation of the phonetic structure of words to a lesser degree than it is for hearing spellers.     

Attentional control and reflexive orienting to gaze and arrow cues

A wealth of data indicate that central spatially nonpredictive eyes and arrows trigger very similar reflexive spatial orienting, although the effects of eyes may be more strongly reflexive (e.g., Friesen, Ristic, & Kingstone, 2004). Pratt and Hommel (2003) recently reported that the orienting effect for arrows is sensitive to arbitrary cue-target color contingencies; for example, an attentional orienting effect for blue colored arrows is evident only for blue targets. We reasoned that if the orienting effect elicited by eye direction is more strongly reflexive than the orienting effect elicited by arrow direction, it follows that eyes, unlike arrows, may trigger orienting effects that generalize across congruent and incongruent cue-target color contingencies. Replicating Pratt and Hommel (2003), we found that the reflexive attention effect elicited by arrows is specific to color-congruent target stimuli. The attention effect triggered by eyes, however, generalizes across color-congruent and color-incongruent target stimuli. These data support the hypothesis that eye direction and arrow direction trigger similar reflexive shifts in spatial attention, but that the attention effect triggered by eye direction is more strongly reflexive.     

Tracking the transition from sublexical to lexical processing: On the creation of orthographic and phonological lexical representations

Participants read aloud nonword letter strings, one at a time, which varied in the number of letters. The standard result is observed in two experiments; the time to begin reading aloud increases as letter length increases. This result is standardly understood as reflecting the operation of a serial, left-to-right translation of graphemes into phonemes. The novel result is that the effect of letter length is statistically eliminated by a small number of repetitions. This elimination suggests that these nonwords are no longer always being read aloud via a serial left-to-right sublexical process. Instead, the data are taken as evidence that new orthographic and phonological lexical entries have been created for these nonwords and are now read at least sometimes by recourse to the lexical route. Experiment 2 replicates the interaction between nonword letter length and repetition observed in Experiment 1 and also demonstrates that this interaction is not seen when participants merely classify the string as appearing in upper or lower case. Implications for existing dual-route models of reading aloud and Share's self-teaching hypothesis are discussed.