Publications

Abstract

This eye-tracking study explored how phonological encoding and speech production planning for successive words are coordinated in adult readers with dyslexia (N = 22) and control readers (N = 25) during rapid automatized naming (RAN). Using an object-RAN task, we orthogonally manipulated the word-form frequency and phonological neighborhood density of the object names and assessed the effects on speech and eye movements and their temporal coordination. In both groups, there was a significant interaction between word frequency and neighborhood density: shorter fixations for dense than for sparse neighborhoods were observed for low-, but not for high-frequency words. This finding does not suggest a specific difficulty in lexical phonological access in dyslexia. However, in readers with dyslexia only, these lexical effects percolated to the late processing stages, indicated by longer offset eye-speech lags. We close by discussing potential reasons for this finding, including suboptimal specification of phonological representations and deficits in attention control or in multi-item coordination.

Abstract

Luria (1976) famously observed that people who never learnt to read and write do not perceive visual illusions. We conducted a conceptual replication of the Luria study of the effect of literacy on the processing of visual illusions. We designed two carefully controlled experiments with 161 participants with varying literacy levels ranging from complete illiterates to high literates in Chennai, India. Accuracy and reaction time in the identification of two types of visual shape and color illusions and the identification of appropriate control images were measured. Separate statistical analyses of Experiments 1 and 2 as well as pooled analyses of both experiments do not provide any support for the notion that literacy effects the perception of visual illusions. Our large sample, carefully controlled study strongly suggests that literacy does not meaningfully affect the identification of visual illusions and raises some questions about other reports about cultural effects on illusion perception.

Abstract

Some theorists posit the existence of a ‘core’ grammar that virtually all native speakers acquire, and a ‘peripheral’ grammar that many do not. We investigated the viability of such a categorical distinction in the Dutch language. We first consulted linguists’ intuitions as to the ‘core’ or ‘peripheral’ status of a wide range of grammatical structures. We then tested a selection of core- and peripheral-rated structures on naïve participants with varying levels of literacy experience, using grammaticality judgment as a proxy for receptive knowledge. Overall, participants demonstrated better knowledge of ‘core’ structures than ‘peripheral’ structures, but the considerable variability within these categories was strongly suggestive of a continuum rather than a categorical distinction between them. We also hypothesised that individual differences in the knowledge of core and peripheral structures would reflect participants’ literacy experience. This was supported only by a small trend in our data. The results fit best with the notion that more frequent syntactic structures are mastered by more people than infrequent ones and challenge the received sense of a categorical core-periphery distinction.

Abstract

Language comprehenders can use syntactic cues to generate predictions online about upcoming language. Previous research with reading-impaired adults and healthy, low-proficiency adult and child learners suggests that reading skills are related to prediction in spoken language comprehension. Here we investigated whether differences in literacy are also related to predictive spoken language processing in non-reading-impaired proficient adult readers with varying levels of literacy experience. Using the visual world paradigm enabled us to measure prediction based on syntactic cues in the spoken sentence, prior to the (predicted) target word. Literacy experience was found to be the strongest predictor of target anticipation, independent of general cognitive abilities. These findings suggest that a) experience with written language can enhance syntactic prediction of spoken language in normal adult language users, and b) processing skills can be transferred to related tasks (from reading to listening) if the domains involve similar processes (e.g., predictive dependencies) and representations (e.g., syntactic).

Abstract

‘Book language’ offers a richer linguistic experience than typical conversational speech in terms of its syntactic properties. Here, we investigated the role of long-term syntactic experience on syntactic knowledge and processing. In a pre-registered study with 161 adult native Dutch speakers with varying levels of literacy, we assessed the contribution of individual differences in written language experience to offline and online syntactic processes. Offline syntactic knowledge was assessed as accuracy in an auditory grammaticality judgment task in which we tested violations of four Dutch grammatical norms. Online syntactic processing was indexed by syntactic priming of the Dutch dative alternation, using a comprehension-to-production priming paradigm with auditory presentation. Controlling for the contribution of non-verbal IQ, verbal working memory, and processing speed, we observed a robust effect of literacy experience on the detection of grammatical norm violations in spoken sentences, suggesting that exposure to the syntactic complexity and diversity of written language has specific benefits for general (modality-independent) syntactic knowledge. We replicated previous results by finding robust comprehension-to-production structural priming, both with and without lexical overlap between prime and target. Although literacy experience affected the usage of syntactic alternates in our large sample, it did not modulate their priming. We conclude that amount of experience with written language increases explicit awareness of grammatical norm violations and changes the usage of (PO vs. DO) dative spoken sentences but has no detectable effect on their implicit syntactic priming in proficient language users. These findings constrain theories about the effect of long-term experience on syntactic processing.

Abstract

Learning a script with mirrored graphs (e.g., d ≠ b) requires overcoming the evolutionary-old perceptual tendency to process mirror images as equivalent. Thus, breaking mirror invariance offers an important tool for understanding cultural re-shaping of evolutionarily ancient cognitive mechanisms. Here we investigated the role of script (i.e., presence vs. absence of mirrored graphs: Latin alphabet vs. Tamil) by revisiting mirror-image processing by illiterate, Tamil monoliterate, and Tamil-Latin-alphabet bi-literate adults. Participants performed two same-different tasks (one orientation-based, another shape-based) on Latin-alphabet letters. Tamil monoliterate were significantly better than illiterate and showed good explicit mirror-image discrimination. However, only bi-literate adults fully broke mirror invariance: slower shape-based judgments for mirrored than identical pairs and reduced disadvantage in orientation-based over shape-based judgments of mirrored pairs. These findings suggest learning a script with mirrored graphs is the strongest force for breaking mirror invariance.

Abstract

A wealth of studies has shown that more proficient monolingual speakers are better at predicting upcoming information during language comprehension. Similarly, prediction skills of adult second language (L2) speakers in their L2 have also been argued to be modulated by their L2 proficiency. How exactly language proficiency and prediction are linked, however, is yet to be systematically investigated. One group of language users which has the potential to provide invaluable insights into this link is bilingual children. In this paper, we compare bilingual children’s prediction skills with those of monolingual children and adult L2 speakers, and show how investigating bilingual children’s prediction skills may contribute to our understanding of how predictive processing works.

Abstract

An important debate on the architecture of the language faculty has been the extent to which it relies on a compositional system that constructs larger units from morphemes to words to phrases to utterances on the fly and in real time using grammatical rules; or a system that chunks large preassembled, stored units of language from memory; or some combination of both approaches. Good empirical evidence exists for both ’computed’ and ’large stored’ forms in language, but little is known about what shapes multi-word storage / access or compositional processing. Here we explored whether predictive and retrodictive processes are a likely determinant of multi-word storage / processing. Our results suggest that forward and backward predictability are independently informative in determining the lexical cohesiveness of multi-word phrases. In addition, our results call for a reevaluation of the role of retrodiction in contemporary language processing accounts (cf. Ferreira and Chantavarin 2018).

Abstract

Does life-long literacy experience modulate syntactic priming in spoken language processing? Such a postulated influence is compatible with usage-based theories of language processing that propose that all linguistic skills are a function of accumulated experience with language across life. Here we investigated the effect of literacy experience on syntactic priming in Mandarin in sixty Chinese older adults from Hebei province. Thirty participants were completely illiterate and thirty were literate Mandarin speakers of similar age and socioeconomic background. We first observed usage differences: literates produced robustly more prepositional object (PO) constructions than illiterates. This replicates, with a different sample, language, and cultural background, previous findings that literacy experience affects (baseline) usage of PO and DO transitive alternates. We also observed robust syntactic priming for double-object (DO), but not prepositional-object (PO) dative alternations for both groups. The magnitude of this DO priming however was higher in literates than in illiterates. We also observed that cumulative adaptation in syntactic priming differed as a function of literacy. Cumulative syntactic priming in literates appears to be related mostly to comprehending others, whereas in illiterates it is also associated with repeating self-productions. Further research is needed to confirm this interpretation.

Abstract

Orthographic systems vary dramatically in the extent to which they encode a language’s phonological and lexico-semantic structure. Studies of the effects of orthographic transparency suggest that such variation is likely to have major implications for how the reading system operates. However, such studies have been unable to examine in isolation the contributory effect of transparency on reading due to co-varying linguistic or socio-cultural factors. We first investigated the phonological properties of languages using the range of the world’s orthographic systems (alphabetic; alphasyllabic; consonantal; syllabic; logographic), and found that, once geographical proximity is taken into account, phonological properties do not relate to orthographic system. We then explored the processing implications of orthographic variation by training a connectionist implementation of the triangle model of reading on the range of orthographic systems whilst controlling for phonological and semantic structure. We show that the triangle model is effective as a universal model of reading, able to replicate key behavioural and neuroscientific results. Importantly, the model also generates new predictions deriving from an explicit description of the effects of orthographic transparency on how reading is realised and defines the consequences of orthographic systems on reading processes.

Abstract

Do we structure object-related conceptual information according to real-world sensorimotor experience, or can it also be shaped by linguistic information? This study investigates whether a feature of language coded in grammar—numeral classifiers—affects the conceptual representation of objects. We compared speakers of Mandarin (a classifier language) with speakers of Dutch (a language without classifiers) on how they judged object similarity in four studies. In the first three studies, participants had to rate how similar a target object was to four comparison objects, one of which shared a classifier with the target. Objects were presented as either words or pictures. Overall, the target object was always rated as most similar to the object with the shared classifier, but this was the case regardless of the language of the participant. In a final study employing a successive pile-sorting task, we also found that the underlying object concepts were similar for speakers of Mandarin and Dutch. Speakers of a non-classifier language are therefore sensitive to the same conceptual similarities that underlie classifier systems in a classifier language. Classifier systems may therefore reflect conceptual structure, rather than shape it.

Abstract

A considerable amount of the population in more economically developed countries are functionally illiterate (i.e., low literate). Despite some years of schooling and basic reading skills, these individuals cannot properly read and write and, as a consequence have problems to understand even short texts. An often-discussed approach (Greenberg et al., 1997) assumes weak phonological processing skills coupled with untreated developmental dyslexia as possible causes of functional illiteracy. Although there is some data suggesting commonalities between low literacy and developmental dyslexia, it is still not clear, whether these reflect shared consequences (i.e., cognitive and behavioral profile) or shared causes. The present systematic review aims at exploring the similarities and differences identified in empirical studies investigating both functional illiterate and developmental dyslexic samples. Nine electronic databases were searched in order to identify all quantitative studies published in English or German. Although a broad search strategy and few limitations were applied, only 5 studies have been identified adequate from the resulting 9269 references. The results point to the lack of studies directly comparing functional illiterate with developmental dyslexic samples. Moreover, a huge variance has been identified between the studies in how they approached the concept of functional illiteracy, particularly when it came to critical categories such the applied definition, terminology, criteria for inclusion in the sample, research focus, and outcome measures. The available data highlight the need for more direct comparisons in order to understand what extent functional illiteracy and dyslexia share common characteristics.

Abstract

Written language, a human cultural invention, is far too recent for dedicated neural
infrastructure to have evolved in its service. Culturally newly acquired skills (e.g. reading) thus ‘recycle’ evolutionarily older circuits that originally evolved for different, but similar functions (e.g. visual object recognition). The destructive competition hypothesis predicts that this neuronal recycling has detrimental behavioral effects on the cognitive functions a cortical network originally evolved for. In a study with 97 literate, low-literate, and illiterate participants from the same socioeconomic background we find that even after adjusting for cognitive ability and test-taking familiarity, learning to read is associated with an increase, rather than a decrease, in object recognition abilities. These results are incompatible with the claim that neuronal recycling results in destructive competition and consistent with the possibility that learning to read instead fine-tunes general object recognition mechanisms, a hypothesis that needs further neuroscientific investigation.

Abstract

What does semantic similarity between two concepts mean? How could we measure it? The way in which semantic similarity is calculated might differ depending on the theoretical notion of semantic representation. In an eye-tracking reading experiment, we investigated whether two widely used semantic similarity measures (based on featural or distributional representations) have distinctive effects on sentence reading times. In other words, we explored whether these measures of semantic similarity differ qualitatively. In addition, we examined whether visually perceived spatial distance interacts with either or both of these measures. Our results showed that the effect of featural and distributional representations on reading times can differ both in direction and in its time course. Moreover, both featural and distributional information interacted with spatial distance, yet in different sentence regions and reading measures. We conclude that featural and distributional representations are distinct components of semantic representation.

Abstract

At present, more than one-fifth of humanity is unable to read and write. We critically examine experimental evidence and theories of how (il)literacy affects the human mind. In our discussion we show that literacy has significant cognitive consequences that go beyond the processing of written words and sentences. Thus, cultural inventions such as reading shape general cognitive processing in non-trivial ways. We suggest that this has important implications for educational policy and guidance as well as research into cognitive processing and brain functioning.

Abstract

Despite the efficiency with which language users typically process spoken language, a growing body of research finds substantial individual differences in both the speed and accuracy of spoken language processing potentially attributable to participants’ literacy skills. Against this background, the current study takes a look at the role of word reading skill in listener’s anticipation of upcoming spoken language input in children at the cusp of learning to read: if reading skills impact predictive language processing, then children at this stage of literacy acquisition should be most susceptible to the effects of reading skills on spoken language processing. We tested 8-year-old children on their prediction of upcoming spoken language input in an eye-tracking task. While children, like in previous studies to-date, were successfully able to anticipate upcoming spoken language input, there was a strong positive correlation between children’s word reading (but not their pseudo-word reading and meta-phonological awareness or their spoken word recognition) skills and their prediction skills. We suggest that these findings are most compatible with the notion that the process of learning orthographic representations during reading acquisition sharpens pre-existing lexical representations which in turn also supports anticipation of upcoming spoken words.

Abstract

Three cross-modal priming experiments examined the influence of pre-exposure to
pictures and printed words on the speed of spoken word recognition. Targets for
auditory lexical decision were spoken Dutch words and nonwords, presented in
isolation (Experiments 1 and 2) or after a short phrase (Experiment 3). Auditory
stimuli were preceded by primes which were pictures (Experiments 1 and 3) or those pictures’ printed names (Experiment 2). Prime-target pairs were phonologically onsetrelated (e.g., pijl-pijn, arrow-pain), were from the same semantic category (e.g., pijlzwaard, arrow-sword), or were unrelated on both dimensions. Phonological
interference and semantic facilitation were observed in all experiments. Priming
magnitude was similar for pictures and printed words, and did not vary with picture
viewing time or number of pictures in the display (either one or four). These effects
arose even though participants were not explicitly instructed to name the pictures and where strategic naming would interfere with lexical decision-making. This suggests
that, by default, processing of related pictures and printed words influences how
quickly we recognize related spoken words.

Abstract

Currently one in five adults is still unable to read despite a rapidly developing world. Here we show that (il)literacy has important consequences for the cognitive ability of selecting relevant information from a visual display of non-linguistic material. In two experiments we compared low to high literacy observers on both an easy and a more difficult visual search task involving different types of chicken. Low literates were consistently slower (as indicated by overall RTs) in both experiments. More detailed analyses, including eye movement measures, suggest that the slowing is partly due to display wide (i.e. parallel) sensory processing but mainly due to post-selection processes, as low literates needed more time between fixating the target and generating a manual response. Furthermore, high and low literacy groups differed in the way search performance was distributed across the visual field. High literates performed relatively better when the target was presented in central regions, especially on the right. At the same time, high literacy was also associated with a more general bias towards the top and the left, especially in the more difficult search. We conclude that learning to read results in an extension of the functional visual field from the fovea to parafoveal areas, combined with some asymmetry in scan pattern influenced by the reading direction, both of which also influence other (e.g. non-linguistic) tasks such as visual search.

Abstract

The effect of literacy on phonological processing has been described in terms of a virus that “infects all speech processing” (Frith, 1998). Empirical data has established that literacy leads to changes to the way in which phonological information is processed. Harm & Seidenberg (1999) demonstrated that a connectionist network trained to map between English orthographic and phonological representations display’s more componential phonological processing than a network trained only to stably represent the phonological forms of words. Within this study we use a similar model yet manipulate the transparency of orthographic-to-phonological mappings. We observe that networks trained on a transparent orthography are better at restoring phonetic features and phonemes. However, networks trained on non-transparent orthographies are more likely to restore corrupted phonological segments with legal, coarser linguistic units (e.g. onset, coda). Our study therefore provides an explicit description of how differences in orthographic transparency can lead to varying strains and symptoms of the ‘literacy virus’.

Abstract

When processing language, the cognitive system has access to information from a range of modalities (e.g. auditory, visual) to support language processing. Language mediated visual attention studies have shown sensitivity of the listener to phonological, visual, and semantic similarity when processing a word. In a computational model of language mediated visual attention, that models spoken word processing as the parallel integration of information from phonological, semantic and visual processing streams, we simulate such effects of competition within modalities. Our simulations raised untested predictions about stronger and earlier effects of visual and semantic similarity compared to phonological similarity around the rhyme of the word. Two visual world studies confirmed these predictions. The model and behavioral studies suggest that, during spoken word comprehension, multimodal information can be recruited rapidly to constrain lexical selection to the extent that phonological rhyme information may exert little influence on this process.

Abstract

Multimodal integration is a central characteristic of human cognition. However our understanding of the interaction between modalities and its influence on behaviour is still in its infancy. This paper examines the value of the Hub & Spoke framework (Plaut, 2002; Rogers et al., 2004; Dilkina et al., 2008; 2010) as a tool for exploring multimodal interaction in cognition. We present a Hub and Spoke model of language–vision information interaction and report the model’s ability to replicate a range of phonological, visual and semantic similarity word-level effects reported in the Visual World Paradigm (Cooper, 1974; Tanenhaus et al, 1995). The model provides an explicit connection between the percepts of language and the distribution of eye gaze and demonstrates the scope of the Hub-and-Spoke architectural framework by modelling new aspects of multimodal cognition.

Abstract

Learning to read and write requires an individual to connect additional orthographic representations to pre-existing mappings between phonological and semantic representations of words. Past empirical results suggest that the process of learning to read and write (at least in alphabetic languages) elicits changes in the language processing system, by either increasing the cognitive efficiency of mapping between representations associated with a word, or by changing the granularity of phonological processing of spoken language, or through a combination of both. Behavioural effects of literacy have typically been assessed in offline explicit tasks that have addressed only phonological processing. However, a recent eye tracking study compared high and low literate participants on effects of phonology and semantics in processing measured implicitly using eye movements. High literates’ eye movements were more affected by phonological overlap in online speech than low literates, with only subtle differences observed in semantics. We determined whether these effects were due to cognitive efficiency and/or granularity of speech processing in a multimodal model of speech processing – the amodal shared resource model (ASR, Smith, Monaghan, & Huettig, 2013). We found that cognitive efficiency in the model had only a marginal effect on semantic processing and did not affect performance for phonological processing, whereas fine-grained versus coarse-grained phonological representations in the model simulated the high/low literacy effects on phonological processing, suggesting that literacy has a focused effect in changing the grain-size of phonological mappings.

Abstract

Experiments 1 and 2 examined the time-course of retrieval of phonological, visual-shape and semantic knowledge as Dutch participants listened to sentences and looked at displays of four pictures. Given a sentence with beker, `beaker', for example, the display contained phonological (a beaver, bever), shape (a bobbin, klos), and semantic (a fork, vork) competitors. When the display appeared at sentence onset, fixations to phonological competitors preceded fixations to shape and semantic competitors. When display onset was 200 ms before (e.g.) beker, fixations were directed to shape and then semantic competitors, but not phonological competitors. In Experiments 3 and 4, displays contained the printed names of the previously-pictured entities; only phonological competitors were fixated preferentially. These findings suggest that retrieval of phonological, shape and semantic knowledge in the spoken-word and picture-recognition systems is cascaded, and that visual attention shifts are co-determined by the time-course of retrieval of all three knowledge types and by the nature of the information in the visual environment.

Abstract

Visual attention can be directed immediately, as a spoken word unfolds, towards conceptually related but nonassociated objects, even if they mismatch on other dimensions that would normally determine which objects in the scene were appropriate referents for the unfolding word (Huettig & Altmann, 2005). Here we demonstrate that the mapping between language and concurrent visual objects can also be mediated by visual-shape relations. On hearing "snake", participants directed overt attention immediately, within a visual display depicting four objects, to a picture of an electric cable, although participants had viewed the visual display with four objects for approximately 5 s before hearing the target word - sufficient time to recognize the objects for what they were. The time spent fixating the cable correlated significantly with ratings of the visual similarity between snakes in general and this particular cable. Importantly, with sentences contextually biased towards the concept snake, participants looked at the snake well before the onset of "snake", but they did not look at the visually similar cable until hearing "snake". Finally, we demonstrate that such activation can, under certain circumstances (e.g., during the processing of dominant meanings of homonyms), constrain the direction of visual attention even when it is clearly contextually inappropriate. We conclude that language-mediated attention can be guided by a visual match between spoken words and visual objects, but that such a match is based on lexical input and may not be modulated by contextual appropriateness.