References of "Schiltz, Christine 50003015"
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See detailHow the human brain discriminates numerosities: A steady-state visual-evoked potentials study
Mejias, Sandrine; Rossion, Bruno; Schiltz, Christine UL

Poster (2013, May 28)

This study aimed at measuring rapidly and objectively human adults' sensitivity to (non)symbolic numerical stimuli, using the steady-state visual-evoked potentials (1) response in the context of ... [more ▼]

This study aimed at measuring rapidly and objectively human adults' sensitivity to (non)symbolic numerical stimuli, using the steady-state visual-evoked potentials (1) response in the context of repetition suppression (2). It aimed to demonstrate the feasibility of the method and evaluate its potential to tap into the basic numerical representation systems that can be assumed to underlie symbolic and non-symbolic magnitude comparisons. Following a short duration experiment, we observed a large reduction of signal specifically at the 3.5 Hz response, over the occipito-temporo-parietal cortex. This reduction was greater for symbolic than non-symbolic control stimuli. This first observation of repetition suppression to fast periodic stimulation of symbolic and non-symbolic numerosities in the human brain offers a promising tool to study the sensitivity to numerosities in the human brain in adults, but also especially in children. [less ▲]

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See detailThe influence of language on exact additions in bilinguals.
Van Rinsveld, Amandine UL; Brunner, Martin UL; Landerl, Karin et al

Scientific Conference (2013, May)

To which degree is language involved in arithmetic and dependent on language proficiency? We investigated this question in a German-French educational bilingual setting in Luxembourg, where there is a ... [more ▼]

To which degree is language involved in arithmetic and dependent on language proficiency? We investigated this question in a German-French educational bilingual setting in Luxembourg, where there is a progressive transition from German to French as a teaching language. Due to this shift, students become increasingly more proficient in the non-dominant language (French) throughout the school years. Interestingly, the decades and units of two-digit number names follow the unit-decade order in German but the decade-unit order in French. Students from grades 7, 8, 10, 11, and German-French adults (total N = 200) solved simple and complex additions presented in different conditions: (1) visual Arabic digits, (2) auditory presentation, and (3) as a dual task in which visually presented additions were preceded by visually presented semantic judgements to indirectly activate a language context. Participants performed each condition in a German and a French testing session. Participants were asked to respond orally in the testing language. Measures include correct responses and response times. The results suggest that language proficiency is crucial for the computation of complex additions, whereas simple additions can be retrieved equally well in both languages. Furthermore, additional error analyses showed more errors on the decade or on the unit digit depending on the language of the task. However, providing a language context seems to enhance performances only in the non-dominant language. Taken together, these results support the view of a strong language influence on arithmetic. [less ▲]

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See detailThe influence of language on exact additions in bilingual adults.
Van Rinsveld, Amandine UL; Brunner, Martin UL; Landerl, Karin et al

Poster (2013, April)

To which degree is language involved in arithmetic? We investigated this question in a German-French bilingual setting. In Luxembourg, bilingualism is acquired through education: mathematics are taught in ... [more ▼]

To which degree is language involved in arithmetic? We investigated this question in a German-French bilingual setting. In Luxembourg, bilingualism is acquired through education: mathematics are taught in German in primary and in French in secondary school. Interestingly, the decades and units within two-digit number names follow the unit-decade order in German but the decade-unit order in French. Forty-eight bilingual adults performed simple and complex additions. Participants had to orally respond either in German or in French. Additions were presented in different conditions: (1) visual Arabic presentation, (2) auditory presentation (in German or in French), and (3) as a dual task in which visually presented additions were preceded by visually presented semantic judgments to indirectly activate a German or French language context. The results showed that participants performed complex calculations better in the dominant language (German), while there were no differences for simple calculations. Thus, language proficiency seems to be crucial for the computation of more complex calculations, whereas arithmetic facts can be retrieved equally well in both languages. Further, adding language at the input level (auditory presentation) enhanced performances for simple calculations, especially in the non-dominant language (French), while it was exactly the opposite effect for complex calculations. Additionally, visual additions were better performed within a surrounding linguistic context (3) than alone (1) in their non-dominant language, suggesting the crucial role of the linguistic context of an addition task in bilinguals. Taken together, these results support the view of a strong language impact on calculations. [less ▲]

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See detailEstimation abilities of large numerosities in preschool children: Do they depend on school grade and socio-economic background?
Mejias, Sandrine; Schiltz, Christine UL

Poster (2013, March 01)

The approximate number system (ANS) is thought to be a building block for the elaboration of formal mathematics. However, little is known about how this core system develops and if it can be influenced by ... [more ▼]

The approximate number system (ANS) is thought to be a building block for the elaboration of formal mathematics. However, little is known about how this core system develops and if it can be influenced by external factors at a young age (before the child enters formal numeracy education). The purpose of this study was to examine numerical magnitude representations of 5-6 year old children at 2 different moments of Kindergarten considering children's early number competence as well as schools' socio-economic index (SEI). This study investigated estimation abilities of large numerosities using symbolic and non-symbolic output formats (8-64). In addition, we assessed symbolic and non-symbolic early number competence (1-12) at the end of the 2nd (N = 42) and the 3rd (N = 32) Kindergarten grade. By letting children freely produce estimates we observed surprising estimation abilities at a very young age (from 5 year on) extending far beyond children's symbolic explicit knowledge. Moreover, the time of testing has an impact on the ANS accuracy since 3rd Kindergarteners were more precise in both estimation tasks. Additionally, children who presented better exact symbolic knowledge were also those with the most refined ANS. However, this was true only for 3rd Kindergarteners who were a few months from receiving math instructions. In a similar vein, higher SEI positively impacted only the oldest children's estimation abilities whereas it played a role for exact early number competences already in 2nd and 3rd graders. Our results support the view that approximate numerical representations are linked to exact number competence in young children before the start of formal math education and might thus serve as building blocks for mathematical knowledge. Since this core number system was also sensitive to external components such as the SEI this implies that it can most probably be targeted and refined through specific educational strategies from preschool on. [less ▲]

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See detailDo the mental number line and spatial sequence synesthesia share neural substrates?
Bien, Nina; Van der Horst, Anne; Sack, Alexander et al

Scientific Conference (2013, March 01)

Detailed reference viewed: 33 (1 UL)
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See detailThe impact of inhibition capacities on number-space associations
Hoffmann, Danielle UL; Pigat, Delia; Schiltz, Christine UL

Poster (2013, March 01)

Numerical and spatial representations are tightly linked (for a review see de Hevia et al., 2008). One specific instance of this link is the finding that when doing a binary classification judgment on ... [more ▼]

Numerical and spatial representations are tightly linked (for a review see de Hevia et al., 2008). One specific instance of this link is the finding that when doing a binary classification judgment on single Arabic digits, participants are faster to respond with their left/right hand to small/large numbers respectively. This observation has first been described by Dehaene and colleagues in the early 1990’s (Dehaene et al., 1993) and termed the SNARC effect (Spatial Numerical Association of Response Codes). Celebrating its 20th anniversary this year, the SNARC effect has been extensively replicated (for a meta-analysis see Wood et al., 2008) but one of its characteristics remains its high inter-individual variability (Wood et al., 2006a; 2006b). The source of this variability can partly be ascribed to differences in mathematical proficiency (Hoffmann et al., submitted) but a more domain general hypothesis implicating general inhibition capacities warrants further investigation. For the present study a total of 77 participants have been evaluated with a SNARC paradigm as well as standard inhibition tests (Stroop, Incompatibility subtest of the TAP test). Results show that when age-appropriate inhibition tests are used, inhibition capacities are strongly correlated with the SNARC effect, in the way that very efficient inhibition capacities lead to weaker SNARC effects. Consequently this finding could at least partly explain the impact of arithmetical proficiency on the SNARC effect. A study combining both measures would be an appropriate next step. [less ▲]

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See detailThe influence of language on exact additions in bilingual pupils and adults.
Van Rinsveld, Amandine UL; Brunner, Martin UL; Landerl, Karin et al

Poster (2013, March)

To which degree is language involved in arithmetic? We investigated this question in a German-French bilingual setting. In Luxembourg, bilingualism is acquired through education: mathematics are taught in ... [more ▼]

To which degree is language involved in arithmetic? We investigated this question in a German-French bilingual setting. In Luxembourg, bilingualism is acquired through education: mathematics are taught in German in primary and in French in secondary school. Interestingly, the decades and units within two-digit number names follow the unit-decade order in German but the decade-unit order in French. We studied our research question in the multi-lingual educational context of Luxembourg by applying a developmental design. The present sample (total N = 200) included students from grades 7, 8, 10 and 11, as well as an adult bilingual group. This sample takes advantage of following the progressive transition from German to French as teaching languages. All participants performed simple and complex additions that they had to orally respond either in German or in French. Additions were presented in different conditions: (1) visual Arabic presentation, (2) auditory presentation (in German or in French), and (3) as a dual task in which visually presented additions were preceded by visually presented semantic judgements to indirectly activate a German or French language context. The results suggested that language proficiency seems to be crucial for the computation of more complex calculations, whereas simple additions can be retrieved equally well in both languages. Taken together, these results support the view of a strong language impact on calculations. Further results and implications will be discussed. [less ▲]

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See detailSensitivity to spacing information increases more for the eye region than for the mouth region during childhood
de Heering, Adélaïde; Schiltz, Christine UL

in International Journal of Behavioral Development (2013), 37(2), 169-174

Sensitivity to spacing information within faces improves with age and reaches maturity only at adolescence. In this study, we tested 6–16-year-old children’s sensitivity to vertical spacing when the eyes ... [more ▼]

Sensitivity to spacing information within faces improves with age and reaches maturity only at adolescence. In this study, we tested 6–16-year-old children’s sensitivity to vertical spacing when the eyes or the mouth is the facial feature selectively manipulated. Despite the similar discriminability of these manipulations when they are embedded in inverted faces (Experiment 1), children’s sensitivity to spacing information manipulated in upright faces improved with age only when the eye region was concerned (Experiment 2). Moreover, children’s ability to process the eye region did not correlate with their selective visual attention, marking the automation of the mechanism (Experiment 2). In line with recent findings, we suggest here that children rely on a holistic/configural face processing mechanism to process the eye region, composed of multiple features to integrate, which steadily improves with age. [less ▲]

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See detailThe impact of inhibition capacities on number-space associations in young and elderly adults
Hoffmann, Danielle UL; Pigat, Delia; Schiltz, Christine UL

Poster (2013, February 26)

Background: Numerical and spatial representations are tightly linked, i.e. when doing a binary classification judgment on Arabic digits participants are faster to respond with their left/right hand to ... [more ▼]

Background: Numerical and spatial representations are tightly linked, i.e. when doing a binary classification judgment on Arabic digits participants are faster to respond with their left/right hand to small/large numbers respectively (SNARC effect, Dehaene et al., 1993). The SNARC effect has been extensively replicated but one of its characteristics remains inter-individual variability (Wood et al., 2006). Different sources have been proposed to account for the reported inter-individual variability, namely response speed (Gevers et al., 2006), inhibition capacities (Wood et al., 2008) and age (Wood et al., 2008). The present study aims to investigate the impact of inhibition capacities on the SNARC effect in young and elderly adults, controlling for individual general processing speed. Methods: Two groups of participants were included: young adults, N=28, mean age: 23 years (SD=3.02) and elderly adults, N=46, mean age: 65.9 years (SD=3.9). Participants performed a parity judgment SNARC paradigm as well as inhibition tests (Stroop, Incompatibility). General processing speed was evaluated using a simple shape matching task. Results: The two age-groups differed in the strength of the SNARC effect, inhibition capacities and processing speed, with the elderly adults displaying stronger SNARC effects, weaker inhibition capacities and slower processing speed. Correlation analysis including all participants confirmed these findings on an individual level by showing relations between the SNARC effect and age, as well as relations between the SNARC effect and both inhibition capacities (i.e. the Stroop effect) and processing speed. When controlling for processing speed, the relations between the SNARC effect and both inhibition capacities and age remained. Conversely, when controlling for inhibition capacities, only the relation between the SNARC effect and age (but not processing speed) remained significant, even when controlling in addition for processing speed. Relevance: By combining the variables age, inhibition capacities and individual processing speed, the present data are the first to reveal a strong link between inhibition capacities and number-space associations. Importantly, we demonstrate that this link is not mediated by general processing speed. Interestingly, the robust relation between the SNARC effect and age remains after controlling for processing speed and inhibition capacities, pointing to a new source of inter-individual differences in the strength of the SNARC effect that will need to be clarified in future research projects. [less ▲]

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See detailLocal discriminability determines the strength of holistic processing for faces in the fusiform face area
Goffaux, Valerie; Schiltz, Christine UL; Mur, Marieke et al

in Frontiers in Psychology [=FPSYG] (2013), 3

Recent evidence suggests that the Fusiform Face Area (FFA) is not exclusively dedicated to the interactive processing of face features, but also contains neurons sensitive to local features.This suggests ... [more ▼]

Recent evidence suggests that the Fusiform Face Area (FFA) is not exclusively dedicated to the interactive processing of face features, but also contains neurons sensitive to local features.This suggests the existence of both interactive and local processing modes, consistent with recent behavioral findings that the strength of interactive feature processing (IFP) engages most strongly when similar features need to be disambiguated. Here we address whether the engagement of the FFA into interactive versus featural representational modes is governed by local feature discriminability.We scanned human participants while they matched target features within face pairs, independently of the context of distracter features. IFP was operationalized as the failure to match the target without being distracted by distracter features. Picture-plane inversion was used to disrupt IFP while preserving input properties.We found that FFA activationwas comparably strong, irrespective of whether similar target features were embedded in dissimilar contexts(i.e., inducing robust IFP) or dissimilar target featureswere embedded in the same context (i.e., engaging local processing). Second, inversion decreased FFA activation to faces most robustly when similar target features were embedded in dissimilar contexts, indicating that FFA engages into IFP mainly when features cannot be disambiguated at a local level.Third, by means of Spearman rank correlation tests, we show that the local processing of feature differences in the FFA is supported to a large extent by the Occipital Face Area, the Lateral Occipital Complex, and early visual cortex, suggesting that these regions encode the local aspects of face information. The present findings confirm the co-existence of holistic and featural representations in the FFA. Furthermore, they establish FFA as the main contributor to the featural/holistic representational mode switches determined by local discriminability. [less ▲]

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See detailEstimation abilities of large numerosities in Kindergartners.
Mejias, Sandrine; Schiltz, Christine UL

in Frontiers in psychology (2013), 4

The approximate number system (ANS) is thought to be a building block for the elaboration of formal mathematics. However, little is known about how this core system develops and if it can be influenced by ... [more ▼]

The approximate number system (ANS) is thought to be a building block for the elaboration of formal mathematics. However, little is known about how this core system develops and if it can be influenced by external factors at a young age (before the child enters formal numeracy education). The purpose of this study was to examine numerical magnitude representations of 5-6 year old children at 2 different moments of Kindergarten considering children's early number competence as well as schools' socio-economic index (SEI). This study investigated estimation abilities of large numerosities using symbolic and non-symbolic output formats (8-64). In addition, we assessed symbolic and non-symbolic early number competence (1-12) at the end of the 2nd (N = 42) and the 3rd (N = 32) Kindergarten grade. By letting children freely produce estimates we observed surprising estimation abilities at a very young age (from 5 year on) extending far beyond children's symbolic explicit knowledge. Moreover, the time of testing has an impact on the ANS accuracy since 3rd Kindergarteners were more precise in both estimation tasks. Additionally, children who presented better exact symbolic knowledge were also those with the most refined ANS. However, this was true only for 3rd Kindergarteners who were a few months from receiving math instructions. In a similar vein, higher SEI positively impacted only the oldest children's estimation abilities whereas it played a role for exact early number competences already in 2nd and 3rd graders. Our results support the view that approximate numerical representations are linked to exact number competence in young children before the start of formal math education and might thus serve as building blocks for mathematical knowledge. Since this core number system was also sensitive to external components such as the SEI this implies that it can most probably be targeted and refined through specific educational strategies from preschool on. [less ▲]

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See detailThe SNARC effect and its relationship to spatial abilities in women
Georges, Carrie UL; Hoffmann, Danielle UL; Schiltz, Christine UL

Poster (2013)

A classical demonstration of number-space associations is the so-called SNARC (Spatial Numerical Association of Response Codes) effect. It consists in faster reaction times to small/large digits with the ... [more ▼]

A classical demonstration of number-space associations is the so-called SNARC (Spatial Numerical Association of Response Codes) effect. It consists in faster reaction times to small/large digits with the left/right hand respectively. To get a better understanding of the well-documented inter-individual variability in the SNARC effect, we investigated the relationship between the classically used parity SNARC and spatial abilities, as indexed by visuo-spatial working memory capacity (WMC). The study population consisted of female university students (n=20; mean age=23.79; SD=2.50) recruited in the fields of humanities and educational sciences. Since systematic studies on the reliability of the SNARC effect are still lacking, we first measured the internal consistency, as assessed by split-half reliability, as well as test-retest reliability of the parity SNARC. Split-half and test-retest correlation coefficients were (r(19)=0.41; p<0.05) and (r(19)=0.25; p=0.14) respectively, indicating a trend towards consistency. In the present female population, a significant negative correlation was revealed between the strength of the parity SNARC effect (mean slope=-10.04; SD=8.66) and visuo-spatial WMC (mean WMC=2.85; SD=1.12; r(19)=-0.51; p<0.05). This finding thus indicates that number-space associations as measured by the parity SNARC effect tend to be stronger in young female adults with higher spatial abilities. [less ▲]

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See detailHow the human brain discriminates numerosities: A steady-state visual-evoked potentials study
Mejias, Sandrine; Rossion, Bruno; Schiltz, Christine UL

Poster (2013)

This study aimed at measuring rapidly and objectively human adults' sensitivity to (non)symbolic numerical stimuli, using the steady-state visual-evoked potentials (1) response in the context of ... [more ▼]

This study aimed at measuring rapidly and objectively human adults' sensitivity to (non)symbolic numerical stimuli, using the steady-state visual-evoked potentials (1) response in the context of repetition suppression (2). It aimed to demonstrate the feasibility of the method and evaluate its potential to tap into the basic numerical representation systems that can be assumed to underlie symbolic and non-symbolic magnitude comparisons. Following a short duration experiment, we observed a large reduction of signal specifically at the 3.5 Hz response, over the occipito-temporo-parietal cortex. This reduction was greater for symbolic than non-symbolic control stimuli. This first observation of repetition suppression to fast periodic stimulation of symbolic and non-symbolic numerosities in the human brain offers a promising tool to study the sensitivity to numerosities in the human brain in adults, but also especially in children. [less ▲]

Detailed reference viewed: 34 (7 UL)
See detailNumber-space interactions and how they develop over lifespan
Schiltz, Christine UL

Presentation (2012, December 05)

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See detailAttentional shifts induced by uninformative number symbols modulate neural activity in human occipital cortex
Goffaux, Valerie; Martin, Romain UL; Dormal, Giulia et al

in Neuropsychologia (2012), 50

Number processing interacts with space encoding in a wide variety of experimental paradigms. Most intriguingly, the passive viewing of uninformative number symbols can shift visuo-spatial attention to ... [more ▼]

Number processing interacts with space encoding in a wide variety of experimental paradigms. Most intriguingly, the passive viewing of uninformative number symbols can shift visuo-spatial attention to different target locations according to the number magnitude, i.e., small/large numbers facilitate processing of left/right targets, respectively. The brain architecture dedicated to these attention shifts associated with numbers currently remains unknown. Evoked potential recordings indicate that both early and late stages are involved in this spatio-numerical interaction, but the neuro-functional anatomy needs to be specified. Here we use, for the first time, functional magnetic resonance imaging (fMRI) to investigate attentional orienting following uninformative Arabic digits. We show that BOLD response in occipital visual regions was modulated by the congruency between digit magnitude (small/large) and target side (left/right). Additionally, we report higher BOLD responses following large (8, 9) compared to small (1, 2) digits in two bilateral parietal regions, yielding a significant effect of digit magnitude. We propose and discuss the view that encoding of semantic representations related to number symbols in parietal cortex led to shifts in visuo-spatial attention and enhanced visual processing in the occipital cortex according to number-space congruency rules. [less ▲]

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See detailAttentional shifts induced by uninformative number symbols modulate neural activity in human occipital cortex
Goffaux, Valérie; Martin, Romain UL; Dormal, Giulia et al

in Neuropsychologia (2012), 50

Number processing interacts with space encoding in a wide variety of experimental paradigms. Most intriguingly, the passive viewing of uninformative number symbols can shift visuo-spatial attention to ... [more ▼]

Number processing interacts with space encoding in a wide variety of experimental paradigms. Most intriguingly, the passive viewing of uninformative number symbols can shift visuo-spatial attention to different target locations according to the number magnitude, i.e., small/large numbers facilitate processing of left/right targets, respectively. The brain architecture dedicated to these attention shifts associated with numbers remains unknown. Evoked potential recordings indicate that both early and late stages are involved in this spatio-numerical interaction, but the neuro-functional anatomy needs to be specified. Here we use, for the first time, functional magnetic resonance imaging (fMRI) to investigate attentional orienting following uninformative Arabic digits. We show that BOLD response in occipital visual regions is modulated by the congruency between digit magnitude (small/large) and target side (left/right). Additionally, we report higher BOLD responses following large (8, 9) compared to small (1, 2) digits in two bilateral parietal regions, yielding a significant effect of digit magnitude. We propose and discuss the view that encoding of semantic representations related to number symbols in parietal cortex leads to shifts in visuo-spatial attention and enhances visual processing in the occipital cortex according to number-space congruency rules. [less ▲]

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See detailThe interaction between number and space processing and math achievement in adults
Hoffmann, Danielle UL; Mussolin, Christophe; Schiltz, Christine UL

Poster (2012, September 07)

Behavioral studies show a relation between numbers and space (for a review see De Hevia et al., 2008). One instance of this link is the SNARC (Spatial Numerical Association of Response Codes) effect ... [more ▼]

Behavioral studies show a relation between numbers and space (for a review see De Hevia et al., 2008). One instance of this link is the SNARC (Spatial Numerical Association of Response Codes) effect, consisting in faster reaction times responding to small/large digits with the left/right hand respectively (Dehaene et al. 1993). The SNARC effect has often been replicated, but it is also characterized by high inter-subject variability (Wood et al. 2006 a,b). Although differences in mathematical skills are an obvious candidate source for SNARC variability, this variable has not yet been explored systematically. For the present study, three groups of participants were recruited amongst University students; one group included only participants reporting specific problems related to numerical processing, and two control groups differing in the math requirements of their field of study (i.e. science students vs. literature students). Results confirmed that the three groups differed substantially in basic arithmetic scores [F(2,92)=19.97, p<0.001] as well as in the strength of their SNARC effect [F(2,92)=7.12, p=0.001]. The science group had the highest arithmetic score and the smallest SNARC effect and the problem report group had the lowest arithmetic score and the strongest SNARC effect, with the literature group lying in between. Rearranging the groups based on arithmetic performance yielded the same results. Correlation analyses confirmed this finding by revealing a strong relation between arithmetic scores and SNARC effect independently of group constitution [r=-0.28, p<0.01]. Different hypotheses in the context of the relevant literature are discussed. [less ▲]

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See detailOrientation tuning for faces in the Fusiform Face Area and Primary Visual Cortex
Goffaux, Valerie; Duecker, Felix; Schiltz, Christine UL et al

Scientific Conference (2012, September)

Detailed reference viewed: 40 (0 UL)