References of "Lochy, Aliette 50029933"
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See detailAre dates processed like words rather than like numbers? A study of transposition priming effects
Lochy, Aliette UL; Golinvaux, Fanny; Schiltz, Christine UL

Poster (2019, May)

Neuropsychological case-studies suggested that dates and encyclopedic numbers may be processed differently than unknown numbers. However, this issue was not yet investigated in reading in healthy ... [more ▼]

Neuropsychological case-studies suggested that dates and encyclopedic numbers may be processed differently than unknown numbers. However, this issue was not yet investigated in reading in healthy participants, so that it is unclear if dates are read like words and processed as lexical items, or like numbers where each position strictly defines the digit value in a base-10 system. Here, we compared processing of known dates to unknown numbers in a group of 26 experts (students and teachers in History). Participants performed an explicit recognition task on dates (e.g., 1789, 1945, …) and on acronyms (e.g., FNRS, HDMI, …), half known and half unknown. They were preceded by an identical prime (e.g., 1945-1945), a transposed-character prime (e.g., 1495-1945) or a substituted-character prime (e.g., 1635-1945). Results show that for dates, there is a significant transposition gain (-57ms), while for unknown numbers as well as for acronyms (known and unknown), the transposed-character prime induced a cost (from +17 to +257ms) rather than a gain. The facilitation due to transposed characters found here on dates is similar to what is observed in studies of lexical decision on words. Therefore, it suggests that dates may be processed with similar types of orthographical mechanisms than words. [less ▲]

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See detailLateralization for faces in prereaders depends on the perceptual processing level: An EEG Fast Periodic Visual Stimulation study
Lochy, Aliette UL; Schiltz, Christine UL; Rossion, Bruno

Poster (2019, January)

The developmental origin of human adults’ right hemispheric lateralization to face stimuli is unclear, in particular because young infants’ right hemispheric advantage in face perception is no longer ... [more ▼]

The developmental origin of human adults’ right hemispheric lateralization to face stimuli is unclear, in particular because young infants’ right hemispheric advantage in face perception is no longer present in preschool children, before written language acquisition. Here we used fast periodic visual stimulation (FPVS) with scalp electrophysiology to test 52 preschool children (5 years old) at two levels of face processing (i.e., faces vs. objects, or discrimination between individual faces). While the contrast between faces and nonface objects elicits strictly bilateral occipital responses in children, discrimination of faces on the basis of identity in the same children is associated with a strong right hemispheric lateralization over the occipito-temporal cortex. Inversion of the face stimuli does not modulate right lateralization but significantly decreases the discrimination response. Furthermore, there is no relationship between right hemispheric lateralization in individual face discrimination and preschool levels of letter recognition. These observations suggest that right lateralization for face perception is essentially driven by the necessity to process faces at the level of identity. Overall, they also challenge the view that the adult right hemispheric lateralization for face perception emerges late and slowly during childhood due to increased competition with left lateralized posterior network for reading. [less ▲]

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See detailThe non-linear development of the right hemispheric specialization for human face perception
Lochy, Aliette UL; de Heering, Adelaïde; Rossion, Bruno

in Neuropsychologia (2019), 126

The developmental origins of human adults’ right hemispheric specialization for face perception remain unclear. On the one hand, infant studies have shown a right hemispheric advantage for face perception ... [more ▼]

The developmental origins of human adults’ right hemispheric specialization for face perception remain unclear. On the one hand, infant studies have shown a right hemispheric advantage for face perception. On the other hand, it has been proposed that the adult right hemispheric lateralization for face perception slowly emerges during childhood due to reading acquisition, which increases left lateralized posterior responses to competing written material (e.g., visual letters and words). Since methodological approaches used in infant and children typically differ when their face capabilities are explored, resolving this issue has been difficult. Here we tested 5- year-old preschoolers varying in their level of visual letter knowledge with the same fast periodic visual stimulation (FPVS) paradigm leading to strongly right lateralized electrophysiological occipito-temporal face-selective responses in 4- to 6-month-old infants (de Heering and Rossion, 2015). Children's face-selective response was quantitatively larger and differed in scalp topography from infants’, but did not differ across hemispheres. There was a small positive correlation between preschoolers’ letter knowledge and a non-normalized index of right hemispheric specialization for faces. These observations show that previous discrepant results in the literature reflect a genuine nonlinear development of the neural processes underlying face perception and are not merely due to methodological differences across age groups. We discuss several factors that could contribute to the adult right hemispheric lateralization for faces, such as myelination of the corpus callosum and reading acquisition. Our findings point to the value of FPVS coupled with electroencephalography to assess specialized face perception processes throughout development with the same methodology [less ▲]

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See detailCortical networks in learning to read
Lochy, Aliette UL

Scientific Conference (2018, June)

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See detailAutomatic discrimination of digits and letters in first graders and adults: an EEG Fast Periodic Visual Stimulation study.
Lochy, Aliette UL; Schiltz, Christine UL

Poster (2018, June)

Both letters and digits are arbitrary visual shapes that are distinguished into categories only after cultural acquisition. The observation that digits are easier to identify than letters has been ... [more ▼]

Both letters and digits are arbitrary visual shapes that are distinguished into categories only after cultural acquisition. The observation that digits are easier to identify than letters has been repeatedly reported in the literature (Shubert, 2017). In the present study, we used a Fast Periodic Visual Stimulation approach with EEG recordings to assess the automatic discrimination of letters and digits from each other in 1st grade children (N=17) and in adults (N=18). Participants viewed 40 sec sequences (3 repetitions per condition) of frequent stimuli (letters or digits) at a fast periodic rate (adults: 10Hz, children: 6Hz), in which rare stimuli (the other category of alphanumeric symbols) were periodically inserted (every five items, e.g., adults: at 2Hz, children: at 1.2Hz). Results showed discrimination responses in both groups in posterior occipito-temporal regions with clear changes in lateralization patterns. In children, stimuli contained only single elements. Responses were right-lateralized for digits among letters, and revealed a trend for left-lateralization for letters among digits. In adults, when stimuli contained only 1 character, both letters and digits gave rise to responses in the RH. However, when strings of characters were presented, then letters were discriminated from digits in the LH. These findings show a developmental pattern where single elements in children seem to be processed like strings of elements in adults. [less ▲]

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See detailDoes Extensive Training at Individuating Novel Objects in Adulthood Lead to Visual Expertise? The Role of Facelikeness.
Lochy, Aliette UL; Zimmermann, Friederike G. S.; Laguesse, Renaud et al

in Journal of cognitive neuroscience (2018), 30(4), 449-467

Human adults have a rich visual experience thanks to seeing human faces since birth, which may contribute to the acquisition of perceptual processes that rapidly and automatically individuate faces ... [more ▼]

Human adults have a rich visual experience thanks to seeing human faces since birth, which may contribute to the acquisition of perceptual processes that rapidly and automatically individuate faces. According to a generic visual expertise hypothesis, extensive experience with nonface objects may similarly lead to efficient processing of objects at the individual level. However, whether extensive training in adulthood leads to visual expertise remains debated. One key issue is the extent to which the acquisition of visual expertise depends on the resemblance of objects to faces in terms of the spatial configuration of parts. We therefore trained naive human adults to individuate a large set of novel parametric multipart objects. Critically, one group of participants trained with the objects in a "facelike" stimulus orientation, whereas a second group trained with the same objects but with the objects rotated 180 degrees in the picture plane into a "nonfacelike" orientation. We used a fast periodic visual stimulation EEG protocol to objectively quantify participants' ability to discriminate untrained exemplars before and after training. EEG responses associated with the frequency of identity change in a fast stimulation sequence, which reflects rapid and automatic perceptual processes, were observed over lateral occipital sites for both groups before training. There was a significant, albeit small, increase in these responses after training but only for the facelike group and only to facelike stimuli. Our findings indicate that perceived facelikeness plays a role in visual expertise and highlight how the adult perceptual system exploits familiar spatial configurations when learning new object categories. [less ▲]

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See detailSelective visual representation of letters and words in the left ventral occipito-temporal cortex with intracerebral recordings.
Lochy, Aliette UL; Jacques, Corentin; Maillard, Louis et al

in Proceedings of the National Academy of Sciences of the United States of America (2018), 115(32), 7595-7604

We report a comprehensive cartography of selective responses to visual letters and words in the human ventral occipito-temporal cortex (VOTC) with direct neural recordings, clarifying key aspects of the ... [more ▼]

We report a comprehensive cartography of selective responses to visual letters and words in the human ventral occipito-temporal cortex (VOTC) with direct neural recordings, clarifying key aspects of the neural basis of reading. Intracerebral recordings were performed in a large group of patients (n = 37) presented with visual words inserted periodically in rapid sequences of pseudofonts, nonwords, or pseudowords, enabling classification of responses at three levels of word processing: letter, prelexical, and lexical. While letter-selective responses are found in much of the VOTC, with a higher proportion in left posterior regions, prelexical/lexical responses are confined to the middle and anterior sections of the left fusiform gyrus. This region overlaps with and extends more anteriorly than the visual word form area typically identified with functional magnetic resonance imaging. In this region, prelexical responses provide evidence for populations of neurons sensitive to the statistical regularity of letter combinations independently of lexical responses to familiar words. Despite extensive sampling in anterior ventral temporal regions, there is no hierarchical organization between prelexical and lexical responses in the left fusiform gyrus. Overall, distinct word processing levels depend on neural populations that are spatially intermingled rather than organized according to a strict postero-anterior hierarchy in the left VOTC. [less ▲]

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See detailNeurosciences et lecture
Lochy, Aliette UL

Presentation (2018)

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See detailLearning to read and hemispheric specialization for faces
Lochy, Aliette UL; Rossion, Bruno

Scientific Conference (2017)

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See detailThe non-linear development of the right hemispheric specialization for human face perception.
Lochy, Aliette UL; de Heering, Adelaide; Rossion, Bruno

in Neuropsychologia (2017)

The developmental origins of human adults' right hemispheric specialization for face perception remain unclear. On the one hand, infant studies have shown a right hemispheric advantage for face perception ... [more ▼]

The developmental origins of human adults' right hemispheric specialization for face perception remain unclear. On the one hand, infant studies have shown a right hemispheric advantage for face perception. On the other hand, it has been proposed that the adult right hemispheric lateralization for face perception slowly emerges during childhood due to reading acquisition, which increases left lateralized posterior responses to competing written material (e.g., visual letters and words). Since methodological approaches used in infant and children typically differ when their face capabilities are explored, resolving this issue has been difficult. Here we tested 5-year-old preschoolers varying in their level of visual letter knowledge with the same fast periodic visual stimulation (FPVS) paradigm leading to strongly right lateralized electrophysiological occipito-temporal face-selective responses in 4- to 6-month-old infants (de Heering and Rossion, 2015). Children's face-selective response was quantitatively larger and differed in scalp topography from infants', but did not differ across hemispheres. There was a small positive correlation between preschoolers' letter knowledge and a non-normalized index of right hemispheric specialization for faces. These observations show that previous discrepant results in the literature reflect a genuine nonlinear development of the neural processes underlying face perception and are not merely due to methodological differences across age groups. We discuss several factors that could contribute to the adult right hemispheric lateralization for faces, such as myelination of the corpus callosum and reading acquisition. Our findings point to the value of FPVS coupled with electroencephalography to assess specialized face perception processes throughout development with the same methodology. [less ▲]

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See detailLeft cortical specialization for visual letter strings predicts rudimentary knowledge of letter-sound association in preschoolers.
Lochy, Aliette UL; Van Reybroeck, Marie; Rossion, Bruno

in Proceedings of the National Academy of Sciences of the United States of America (2016), 113(30), 8544-9

Reading, one of the most important cultural inventions of human society, critically depends on posterior brain areas of the left hemisphere in proficient adult readers. In children, this left hemispheric ... [more ▼]

Reading, one of the most important cultural inventions of human society, critically depends on posterior brain areas of the left hemisphere in proficient adult readers. In children, this left hemispheric cortical specialization for letter strings is typically detected only after approximately 1 y of formal schooling and reading acquisition. Here, we recorded scalp electrophysiological (EEG) brain responses in 5-y-old (n = 40) prereaders presented with letter strings appearing every five items in rapid streams of pseudofonts (6 items per second). Within 2 min of recording only, letter strings evoked a robust specific response over the left occipito-temporal cortex at the predefined frequency of 1.2 Hz (i.e., 6 Hz/5). Interindividual differences in the amplitude of this electrophysiological response are significantly related to letter knowledge, a preschool predictor of later reading ability. These results point to the high potential of this rapidly collected behavior-free measure to assess reading ability in developmental populations. These findings were replicated in a second experiment (n = 26 preschool children), where familiar symbols and line drawings of objects evoked right-lateralized and bilaterally specific responses, respectively, showing the specificity of the early left hemispheric dominance for letter strings. Collectively, these findings indicate that limited knowledge of print in young children, before formal education, is sufficient to develop specialized left lateralized neuronal circuits, thereby pointing to an early onset and rapid impact of left hemispheric reentrant sound mapping on posterior cortical development. [less ▲]

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See detailA robust index of lexical representation in the left occipito-temporal cortex as evidenced by EEG responses to fast periodic visual stimulation.
Lochy, Aliette UL; Van Belle, Goedele; Rossion, Bruno

in Neuropsychologia (2015), 66

Despite decades of research on reading, including the relatively recent contributions of neuroimaging and electrophysiology, identifying selective representations of whole visual words (in contrast to ... [more ▼]

Despite decades of research on reading, including the relatively recent contributions of neuroimaging and electrophysiology, identifying selective representations of whole visual words (in contrast to pseudowords) in the human brain remains challenging, in particular without an explicit linguistic task. Here we measured discrimination responses to written words by means of electroencephalography (EEG) during fast periodic visual stimulation. Sequences of pseudofonts, nonwords, or pseudowords were presented through sinusoidal contrast modulation at a periodic 10 Hz frequency rate (F), in which words were interspersed at regular intervals of every fifth item (i.e., F/5, 2 Hz). Participants monitored a central cross color change and had no linguistic task to perform. Within only 3 min of stimulation, a robust discrimination response for words at 2 Hz (and its harmonics, i.e., 4 and 6 Hz) was observed in all conditions, located predominantly over the left occipito-temporal cortex. The magnitude of the response was largest for words embedded in pseudofonts, and larger in nonwords than in pseudowords, showing that list context effects classically reported in behavioral lexical decision tasks are due to visual discrimination rather than decisional processes. Remarkably, the oddball response was significant even for the critical words/pseudowords discrimination condition in every individual participant. A second experiment replicated this words/pseudowords discrimination, and showed that this effect is not accounted for by a higher bigram frequency of words than pseudowords. Without any explicit task, our results highlight the potential of an EEG fast periodic visual stimulation approach for understanding the representation of written language. Its development in the scientific community might be valuable to rapidly and objectively measure sensitivity to word processing in different human populations, including neuropsychological patients with dyslexia and other reading difficulties. [less ▲]

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See detailSpatial associations for musical stimuli: a piano in the head?
Lidji, Pascale; Kolinsky, Regine; Lochy, Aliette UL et al

in Journal of experimental psychology. Human perception and performance (2007), 33(5), 1189-207

This study was aimed at examining whether pitch height and pitch change are mentally represented along spatial axes. A series of experiments explored, for isolated tones and 2-note intervals, the ... [more ▼]

This study was aimed at examining whether pitch height and pitch change are mentally represented along spatial axes. A series of experiments explored, for isolated tones and 2-note intervals, the occurrence of effects analogous to the spatial numerical association of response codes (SNARC) effect. Response device orientation (horizontal vs. vertical), task, and musical expertise of the participants were manipulated. The pitch of isolated tones triggered the automatic activation of a vertical axis independently of musical expertise, but the contour of melodic intervals did not. By contrast, automatic associations with the horizontal axis seemed linked to music training for pitch and, to a lower extent, for intervals. These results, discussed in the light of studies on number representation, provide a new example of the effects of musical expertise on music cognition. [less ▲]

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See detailMultiple levels of letter representation in written spelling: evidence from a single case of dysgraphia with multiple deficits.
de Partz, Marie-Pierre; Lochy, Aliette UL; Pillon, Agnesa

in Behavioural neurology (2005), 16(2-3), 119-44

In this paper, we report a detailed analysis of the impaired performance of a dysgraphic individual, AD, who produced similar rates of letter-level errors in written spelling, oral spelling, and typing ... [more ▼]

In this paper, we report a detailed analysis of the impaired performance of a dysgraphic individual, AD, who produced similar rates of letter-level errors in written spelling, oral spelling, and typing. We found that the distribution of various letter error types displayed a distinct pattern in written spelling on the one hand and in oral spelling and typing on the other. In particular, noncontextual letter substitution errors (i.e., errors in which the erroneous letter that replaces the target letter does not occur elsewhere within the word) were virtually absent in oral spelling and typing and mainly found in written spelling. In contrast, letter deletion errors and multiple-letter errors were typically found in oral spelling and very exceptional in written spelling. Only contextual letter substitution errors (i.e., errors in which the erroneous letter that replaces the target letter is identical to a letter occurring earlier or later in the word) were found in similar proportions in the three tasks. We argue that these contrasting patterns of letter error distribution result from damage to two distinct levels of letter representation and processing within the spelling system, namely, the amodal graphemic representation held in the graphemic buffer and the letter form representation computed by subsequent writing-specific processes. Then, we examined the relationship between error and target in the letter substitution errors produced in written and oral spelling and found evidence that distinct types of letter representation are processed at each of the hypothetized levels of damage: symbolic letter representation at the graphemic level and representation of the component graphic strokes at the letter form processing level. [less ▲]

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See detailNumber processing and basal ganglia dysfunction: a single case study.
Delazer, Margarete; Domahs, Frank; Lochy, Aliette UL et al

in Neuropsychologia (2004), 42(8), 1050-62

Numerical processing has never been investigated in a case of Fahr's disease (FD) and only rarely in cases of basal ganglia dysfunction. The study describes the cognitive decline of a pre-morbidly high ... [more ▼]

Numerical processing has never been investigated in a case of Fahr's disease (FD) and only rarely in cases of basal ganglia dysfunction. The study describes the cognitive decline of a pre-morbidly high-functioning patient (medical doctor) affected by FD and his difficulties in number processing. A MRI scan revealed bilateral calcifications in the basal ganglia and a brain PET showed a massive reduction of glucose metabolism in the basal ganglia and both frontal lobes, but no other brain abnormalities. The patient's cognitive deficits included impairments in problem solving, in cognitive set shifting and in mental flexibility, as well as in verbal memory. These deficits are attributed to the disruption of the dorsolateral prefrontal circuit involving the basal ganglia. In number processing, the patient showed a severe deficit in the retrieval of multiplication facts, deficits in all tasks of numerical problem solving and in the execution of complex procedures. Importantly, he also showed a dense deficit in conceptual knowledge, which concerned all test conditions and all operations. The findings confirm the predictions of the triple code model in so far, as a disruption of cortico-subcortical loops involving the basal-ganglia may lead to specific deficits in fact retrieval. However, no verbal deficit, as assumed in the triple code model and reported in similar cases, could be observed. The present findings further add to current knowledge on numerical processing, showing how fronto-executive dysfunction may disrupt conceptual understanding of arithmetic. This study shows that not only parietal lesions may lead to severe deficits in conceptual understanding, but that basal ganglia lesions leading to frontal dysfunction may have a devastating effect. [less ▲]

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See detailDeficient arithmetic fact retrieval--storage or access problem? A case study.
Kaufmann, Liane; Lochy, Aliette UL; Drexler, Arthur et al

in Neuropsychologia (2004), 42(4), 482-96

This paper aims at clarifying the nature of fact retrieval difficulties in an 18-year-old young man (MO) who exhibited a puzzling pattern of developmental dyscalculia. Contrasting performance on explicit ... [more ▼]

This paper aims at clarifying the nature of fact retrieval difficulties in an 18-year-old young man (MO) who exhibited a puzzling pattern of developmental dyscalculia. Contrasting performance on explicit (production and verification tasks) and implicit (priming) tasks we observed poor overt retrieval of addition and multiplication facts, classical interference effects in verification tasks and inconsistency of error patterns. Hence, MO's performance pattern is suggestive of the existence of a partly stored network of facts (reflecting imperfect storage), but is also compatible with an access deficit according to Warrington and Cipolotti's [Brain 119 (1996) 611] criteria for distinguishing access and storage deficits in dysphasic patients. Furthermore, while MO displayed interference effects in verification tasks, he did not show automatic access to arithmetic facts in implicit tasks. Finally, similar to the findings of Roussel, Fayol, and Barrouillet [European Journal of Cognitive Psychology 14(1) (2002) 61] on normal subjects, MO's performance pattern is suggestive of the existence of differential processing mechanisms for addition and multiplication facts. We propose a unifying mechanism, namely a deficit of the central executive of working memory (WM), that accounts both for the constitution of a fuzzy network of fact representations, and for an access deficit modulated by attentional demands as required in explicit/implicit task paradigms. Overall, our results clearly provide evidence that even in (a developmental) case of a non-perfect network of memory representations (e.g. [Journal of Experimental Psychology: General 117 (1988) 258]), interference effects might be observed. Future studies thus need to be cautious before concluding that interference effects prove the existence of a well-established associative memory network of arithmetic facts. [less ▲]

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See detailSpecific order impairment in arabic number writing: A case-study.
Lochy, Aliette UL; Domahs, Frank; Bartha, Lisa et al

in Cognitive neuropsychology (2004), 21(5), 555-75

The present study examines the transitory deficit in transcoding verbal to Arabic numbers in an aphasic patient, TM. She showed a mild syntactic impairment in syntactic comprehension of verbal numbers ... [more ▼]

The present study examines the transitory deficit in transcoding verbal to Arabic numbers in an aphasic patient, TM. She showed a mild syntactic impairment in syntactic comprehension of verbal numbers, with preserved performance in comprehension of Arabic numbers, in access to semantic representation, as well as in reading of Arabic numbers, but she committed 75% of errors when required to write numbers in the Arabic format to dictation. In conformity to the previous literature on transcoding deficits, the majority of her errors were syntactic (60%). However, most of them were unusual "order errors" (50%) in which lexical digits (e.g., 1 to 9) were written on the left and zeros on the right of the number, which contained in the majority of the cases the correct number of digits. A similar type of errors has been reported in only one previous case study (Delazer & Denes, 1998), but not specifically studied. We discuss hypotheses concerning its origins as stemming from a syntactic disorder within existing models of transcoding (McCloskey, Caramazza, & Basili, 1985; Power & Dal Martello, 1990). We also report kinematic assessment of the patient's handwriting before and after recovery. At time of the second examination, results show that her pattern of movement fluency parallels that of healthy subjects and supports a distinction between two types of zeros within Arabic numbers, in relation to the verbal code and the rules required to produce them. This paper thus also highlights the potential usefulness of using a digitising tablet in the study of transcoding deficits. [less ▲]

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See detailThe acquisition of arithmetic knowledge - an FMRI study.
Delazer, Margarete; Domahs, Frank; Lochy, Aliette UL et al

in Cortex; a journal devoted to the study of the nervous system and behavior (2004), 40(1), 166-7

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See detailTranscoding zeros within complex numerals.
Grana, Alessia; Lochy, Aliette UL; Girelli, Luisa et al

in Neuropsychologia (2003), 41(12), 1611-8

This paper describes a patient (LD) showing a selective syntactic deficit in the production of Arabic numerals. Unlike in previously reported cases, LD's syntactic difficulties result in deletions rather ... [more ▼]

This paper describes a patient (LD) showing a selective syntactic deficit in the production of Arabic numerals. Unlike in previously reported cases, LD's syntactic difficulties result in deletions rather than insertions of zeros, with a reduction of the number magnitude. The pattern of errors highlighted a distinction between "lexical zeros", i.e. the zeros in tens, that are semantically derived, and "syntactic zeros" that are syntactically produced as the result of specific production rules. In LD, only syntactic zeros were affected. Furthermore, the processing of numerals with final zeros was found to be easier than the processing of numerals with internal zeros. This pattern of errors is compatible with the lexical-semantic model of Power and Dal Martello. In this model, in fact, lexical zeros originate from a numerical concept, while syntactic zeros originate from a concatenation operation, plus an overwriting operation leaving one or more intermediary zeros. Thus, lexical zeros may be easier to manipulate than syntactic zeros that merely represent a null quantity associated to a specific power of 10. [less ▲]

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