Improved performance is generally observed when identical copies of a stimulus are presented bila... more Improved performance is generally observed when identical copies of a stimulus are presented bilaterally to both visual half fields (VHFs), relative to unilateral single presentations. We investigated the influence of stimulus notation and processing speed on this bilateral redundancy gain (B-RG) in number comparison. Two experiments were performed with consistent (i.e., two identical copies of Arabic digits or word numerals) and inconsistent (i.e., an Arabic digit in one VHF with a word numeral of the same value in the other VHF) displays (see also for a similar design in number naming). In Experiment 1, the processing speeds of the Arabic digits were faster than the ones of the word numerals while in Experiment 2, the processing speeds of the two stimulus notations were kept equal. A significant difference between consistent and inconsistent conditions was restricted to Experiment 1 in which the processing speeds of the two stimulus notations diverged. These results are discussed in the framework of a simple race model in which two independent hemispheric processes compete for the control of response, and the faster process wins.
We thank Antoine Tavernier for his technical support and Nathalie De Ridder for running Experimen... more We thank Antoine Tavernier for his technical support and Nathalie De Ridder for running Experiment 2. We also thank Wim Fias and Voyko Kavcic for helpful comments on an earlier version of this article.
We investigated bilateral field interactions and hemispheric asymmetry in number comparison. A nu... more We investigated bilateral field interactions and hemispheric asymmetry in number comparison. A numerical comparison task with three different stimulus notations (Arabic numerals, word numerals and bar graphs) was used. In all conditions, a target was displayed in one visual field, simultaneously with a distractor of the same format in the other visual field. Participants had to indicate manually whether the magnitude of the target was small or large, ignoring the distractor stimulus. Only in the condition with Arabic numerals did we obtain some evidence for a LVF advantage, which argues against a strong laterality of number magnitude representations. Significant interactions between target and distractor values were observed, indicating rich interhemispheric interactions. The interactions were mainly situated at the response stage, but the presence of a bilateral identity effect also points to interactions at the input level.
Journal of Experimental Psychology: Human Perception and Performance, 2005
The authors investigated how 2-digit Arabic numerals are named by looking at the effects of maske... more The authors investigated how 2-digit Arabic numerals are named by looking at the effects of masked primes on the naming latencies. Target numerals were named faster when prime and target shared a digit at the same position (e.g., the target 28 primed by 18 and 21). In contrast, naming latencies were slower when prime and target shared 1 or 2 digits at noncorresponding places (e.g., the target 28 primed by 82, 86, or 72). Subsequent experiments showed that these priming effects were situated at the level of the verbal production of the Arabic numerals. The data point to a nonsemantically mediated route from visual input to verbal output in the naming of 2-digit Arabic numerals.
In a binary response setting, it has been frequently observed that small numbers are reacted to f... more In a binary response setting, it has been frequently observed that small numbers are reacted to faster with the left hand and large numbers with the right hand (i. e., the SNARC-effect) which reflects the spatial left-right orientation of the mental number line ( Dehaene, Bossini, & Giraux, 1993 ). In line with the work of Keus and Schwarz (in press ), we investigated the locus of the conflict in the SNARC effect in a parity judgment task with the Arabic numerals 1, 2, 8, or 9. Differences between compatible (left-hand response to 1 or 2 and right-hand response to 8 and 9) and incompatible SNARC conditions (left-hand response to 8 or 9 and right-hand response to 1 or 2) were observed in the lateralized readiness potential (LRP) but not in the peak latency of the P300. In accordance with Keus and colleagues ( Keus, Jenks, & Schwarz, 2005 ), we argue that the locus of the conflict is situated at intermediate response-related stages. However, instead of adopting a single-route processi...
Improved performance is generally observed when identical copies of a stimulus are presented bila... more Improved performance is generally observed when identical copies of a stimulus are presented bilaterally to both visual half fields (VHFs), relative to unilateral single presentations. We investigated the influence of stimulus notation and processing speed on this bilateral redundancy gain (B-RG) in number comparison. Two experiments were performed with consistent (i.e., two identical copies of Arabic digits or word numerals) and inconsistent (i.e., an Arabic digit in one VHF with a word numeral of the same value in the other VHF) displays (see also for a similar design in number naming). In Experiment 1, the processing speeds of the Arabic digits were faster than the ones of the word numerals while in Experiment 2, the processing speeds of the two stimulus notations were kept equal. A significant difference between consistent and inconsistent conditions was restricted to Experiment 1 in which the processing speeds of the two stimulus notations diverged. These results are discussed in the framework of a simple race model in which two independent hemispheric processes compete for the control of response, and the faster process wins.
In the present study we investigated whether the corpus callosum exerts an inhibitory or an integ... more In the present study we investigated whether the corpus callosum exerts an inhibitory or an integrative influence on hemispheric communication of magnitude information by presenting prime-target pairs to the same or opposite hemispheres (intra-and interhemispheric number priming trials). During the experiment, subjects were asked to compare the targets with a fixed reference number and classify them as small or large. The prime stimulus was irrelevant for the task. To examine the interhemispheric communication of magnitude under present task conditions, we made use of a new presentation technique with filler items, thereby eliminating the latency benefit for intrahemispheric priming trials observed in previous studies. The results of this experiment showed equal priming effects for both intra-and interhemispheric priming conditions: stimuli were reacted to faster when the numerical distance between prime and target was smaller (i.e., quantity priming) and when both prime and target required the same response (i.e., response priming). This is in line with the idea of a rapid integration of magnitude information between hemispheres.
We investigated interhemispheric communication and hemispheric style differences (analytic vs. ho... more We investigated interhemispheric communication and hemispheric style differences (analytic vs. holistic) in two-digit Arabic number comparison by employing the divided visual field paradigm. Interhemispheric communication modulated two-digit number comparison in a very specific way. While no advantage of interhemispheric communication was found with unit-decade compatible trials (e.g., 52 and 67, the decade comparison and unit comparison of the two numbers lead to the same response; see , a significant advantage of interhemispheric interactions emerged in the attentionally more demanding incompatible trials (e.g., 47 and 62, decade and unit comparisons do not lead to the same response, because 4 < 6 but 7 > 2), thereby enhancing the efficiency of selective attention (c.f., . Additionally, some results indicated a more analytical processing style in the left hemisphere and a relatively more holistic processing style in the right hemisphere.
Background: Recent cognitive and computational models (e.g. the Interacting Neighbors Model) stat... more Background: Recent cognitive and computational models (e.g. the Interacting Neighbors Model) state that in simple multiplication decade and unit digits of the candidate answers (including the correct result) are represented separately. Thus, these models challenge holistic views of number representation as well as traditional accounts of the classical problem size effect in simple arithmetic (i.e. the finding that large problems are answered slower and less accurate than small problems). Empirical data supporting this view are still scarce. Methods: Data of 24 participants who performed a multiplication verification task with Arabic digits (e.g. 8 × 4 = 36 -true or false?) are reported. Behavioral (i.e. RT and errors) and EEG (i.e. ERP) measures were recorded in parallel. We provide evidence for neighborhood-consistency effects in the verification of simple multiplication problems (e.g. 8 × 4). Behaviorally, we find that decade-consistent lures, which share their decade digit with the correct result (e.g. 36), are harder to reject than matched inconsistent lures, which differ in both digits from the correct result (e.g. 28). This neighborhood consistency effect in product verification is similar to recent observations in the production of multiplication results. With respect to event-related potentials we find significant differences for consistent compared to inconsistent lures in the N400 (increased negativity) and Late Positive Component (reduced positivity). In this respect consistency effects in our paradigm resemble lexico-semantic effects earlier found in simple arithmetic and in orthographic input processing. Our data suggest that neighborhood consistency effects in simple multiplication stem at least partly from central (lexico-semantic') stages of processing. These results are compatible with current models on the representation of simple multiplication facts -in particular with the Interacting Neighbors Model -and with the notion of decomposed representations of two-digit numbers in general.
Starting from the ®nding that currently phonological models of visual word processing predominate... more Starting from the ®nding that currently phonological models of visual word processing predominate, we examined what happened when important morphological information is disclosed in the orthography but not in the phonology. To do so, we made use of a peculiarity in Dutch. In this language, some forms of the present and the past tense of verbs are homophones or homographs. This allowed us to look at the power of orthographic and phonological cues to derive the tense of the verb. Two experiments showed that orthographic cues alone suce to recover the tense of the verb, and that this recovery does not take more time than tense recovery on the basis of a combination of orthographic and phonological cues. On the basis of these results, we conclude that orthographic cues in homophones are very ecient during silent reading. Our ®ndings, however, do not allow us to conclude whether this is due to a direct route from orthography to meaning, or to a specialised, morpho-syntactic back-up strategy elicited by certain sequences of letters.
The present study presents timed norms for 590 pictures in Belgian Dutch. We determined name agre... more The present study presents timed norms for 590 pictures in Belgian Dutch. We determined name agreement and response latencies. Furthermore, we assessed which factors influenced the naming latencies of the pictures. It appeared that age-of-acquisition, the H-statistic (an index of name agreement), and the number of syllables of the dominant response were significant predictors of the naming latencies. These results are discussed in comparison with previous findings.
Quarterly Journal of Experimental Psychology, 2008
A monitoring bias account is often used to explain speech error patterns that seem to be the resu... more A monitoring bias account is often used to explain speech error patterns that seem to be the result of an interactive language production system, like phonological influences on lexical selection errors. A biased monitor is suggested to detect and covertly correct certain errors more often than others. For instance, this account predicts that errors that are phonologically similar to intended words are harder to detect than those that are phonologically dissimilar. To test this, we tried to elicit phonological errors under the same conditions as those that show other kinds of lexical selection errors. In five experiments, we presented participants with high cloze probability sentence fragments followed by a picture that was semantically related, a homophone of a semantically related word, or phonologically related to the (implicit) last word of the sentence. All experiments elicited semantic completions or homophones of semantic completions, but none elicited phonological completion...
The present study presents timed norms for 590 pictures in Belgian Dutch. We determined name agre... more The present study presents timed norms for 590 pictures in Belgian Dutch. We determined name agreement and response latencies. Furthermore, we assessed which factors influenced the naming latencies of the pictures. It appeared that age-of-acquisition, the H-statistic (an index of name agreement), and the number of syllables of the dominant response were significant predictors of the naming latencies. These results are discussed in comparison with previous findings.
In a recent study with the Poffenberger paradigm, Brizzolara et al. reported longer estimates of ... more In a recent study with the Poffenberger paradigm, Brizzolara et al. reported longer estimates of interhemispheric transfer time (IHTT) for children aged 7 years than for adults. They interpreted this finding as evidence for incomplete functional maturity of the corpus callosum in young children. The present study was we were unable to replicate the age effect reported by Brizzolara et al. A closer look at the original study revealed that only 80 observations per child had been collected, which makes it probable that the larger IHTTs in 7-year-olds were caused by stimulus-response compatibility rather than by the lower efficiency of the corpus callosum during childhood years.
Improved performance is generally observed when identical copies of a stimulus are presented bila... more Improved performance is generally observed when identical copies of a stimulus are presented bilaterally to both visual half fields (VHFs), relative to unilateral single presentations. We investigated the influence of stimulus notation and processing speed on this bilateral redundancy gain (B-RG) in number comparison. Two experiments were performed with consistent (i.e., two identical copies of Arabic digits or word numerals) and inconsistent (i.e., an Arabic digit in one VHF with a word numeral of the same value in the other VHF) displays (see also for a similar design in number naming). In Experiment 1, the processing speeds of the Arabic digits were faster than the ones of the word numerals while in Experiment 2, the processing speeds of the two stimulus notations were kept equal. A significant difference between consistent and inconsistent conditions was restricted to Experiment 1 in which the processing speeds of the two stimulus notations diverged. These results are discussed in the framework of a simple race model in which two independent hemispheric processes compete for the control of response, and the faster process wins.
We thank Antoine Tavernier for his technical support and Nathalie De Ridder for running Experimen... more We thank Antoine Tavernier for his technical support and Nathalie De Ridder for running Experiment 2. We also thank Wim Fias and Voyko Kavcic for helpful comments on an earlier version of this article.
We investigated bilateral field interactions and hemispheric asymmetry in number comparison. A nu... more We investigated bilateral field interactions and hemispheric asymmetry in number comparison. A numerical comparison task with three different stimulus notations (Arabic numerals, word numerals and bar graphs) was used. In all conditions, a target was displayed in one visual field, simultaneously with a distractor of the same format in the other visual field. Participants had to indicate manually whether the magnitude of the target was small or large, ignoring the distractor stimulus. Only in the condition with Arabic numerals did we obtain some evidence for a LVF advantage, which argues against a strong laterality of number magnitude representations. Significant interactions between target and distractor values were observed, indicating rich interhemispheric interactions. The interactions were mainly situated at the response stage, but the presence of a bilateral identity effect also points to interactions at the input level.
Journal of Experimental Psychology: Human Perception and Performance, 2005
The authors investigated how 2-digit Arabic numerals are named by looking at the effects of maske... more The authors investigated how 2-digit Arabic numerals are named by looking at the effects of masked primes on the naming latencies. Target numerals were named faster when prime and target shared a digit at the same position (e.g., the target 28 primed by 18 and 21). In contrast, naming latencies were slower when prime and target shared 1 or 2 digits at noncorresponding places (e.g., the target 28 primed by 82, 86, or 72). Subsequent experiments showed that these priming effects were situated at the level of the verbal production of the Arabic numerals. The data point to a nonsemantically mediated route from visual input to verbal output in the naming of 2-digit Arabic numerals.
In a binary response setting, it has been frequently observed that small numbers are reacted to f... more In a binary response setting, it has been frequently observed that small numbers are reacted to faster with the left hand and large numbers with the right hand (i. e., the SNARC-effect) which reflects the spatial left-right orientation of the mental number line ( Dehaene, Bossini, & Giraux, 1993 ). In line with the work of Keus and Schwarz (in press ), we investigated the locus of the conflict in the SNARC effect in a parity judgment task with the Arabic numerals 1, 2, 8, or 9. Differences between compatible (left-hand response to 1 or 2 and right-hand response to 8 and 9) and incompatible SNARC conditions (left-hand response to 8 or 9 and right-hand response to 1 or 2) were observed in the lateralized readiness potential (LRP) but not in the peak latency of the P300. In accordance with Keus and colleagues ( Keus, Jenks, & Schwarz, 2005 ), we argue that the locus of the conflict is situated at intermediate response-related stages. However, instead of adopting a single-route processi...
Improved performance is generally observed when identical copies of a stimulus are presented bila... more Improved performance is generally observed when identical copies of a stimulus are presented bilaterally to both visual half fields (VHFs), relative to unilateral single presentations. We investigated the influence of stimulus notation and processing speed on this bilateral redundancy gain (B-RG) in number comparison. Two experiments were performed with consistent (i.e., two identical copies of Arabic digits or word numerals) and inconsistent (i.e., an Arabic digit in one VHF with a word numeral of the same value in the other VHF) displays (see also for a similar design in number naming). In Experiment 1, the processing speeds of the Arabic digits were faster than the ones of the word numerals while in Experiment 2, the processing speeds of the two stimulus notations were kept equal. A significant difference between consistent and inconsistent conditions was restricted to Experiment 1 in which the processing speeds of the two stimulus notations diverged. These results are discussed in the framework of a simple race model in which two independent hemispheric processes compete for the control of response, and the faster process wins.
In the present study we investigated whether the corpus callosum exerts an inhibitory or an integ... more In the present study we investigated whether the corpus callosum exerts an inhibitory or an integrative influence on hemispheric communication of magnitude information by presenting prime-target pairs to the same or opposite hemispheres (intra-and interhemispheric number priming trials). During the experiment, subjects were asked to compare the targets with a fixed reference number and classify them as small or large. The prime stimulus was irrelevant for the task. To examine the interhemispheric communication of magnitude under present task conditions, we made use of a new presentation technique with filler items, thereby eliminating the latency benefit for intrahemispheric priming trials observed in previous studies. The results of this experiment showed equal priming effects for both intra-and interhemispheric priming conditions: stimuli were reacted to faster when the numerical distance between prime and target was smaller (i.e., quantity priming) and when both prime and target required the same response (i.e., response priming). This is in line with the idea of a rapid integration of magnitude information between hemispheres.
We investigated interhemispheric communication and hemispheric style differences (analytic vs. ho... more We investigated interhemispheric communication and hemispheric style differences (analytic vs. holistic) in two-digit Arabic number comparison by employing the divided visual field paradigm. Interhemispheric communication modulated two-digit number comparison in a very specific way. While no advantage of interhemispheric communication was found with unit-decade compatible trials (e.g., 52 and 67, the decade comparison and unit comparison of the two numbers lead to the same response; see , a significant advantage of interhemispheric interactions emerged in the attentionally more demanding incompatible trials (e.g., 47 and 62, decade and unit comparisons do not lead to the same response, because 4 < 6 but 7 > 2), thereby enhancing the efficiency of selective attention (c.f., . Additionally, some results indicated a more analytical processing style in the left hemisphere and a relatively more holistic processing style in the right hemisphere.
Background: Recent cognitive and computational models (e.g. the Interacting Neighbors Model) stat... more Background: Recent cognitive and computational models (e.g. the Interacting Neighbors Model) state that in simple multiplication decade and unit digits of the candidate answers (including the correct result) are represented separately. Thus, these models challenge holistic views of number representation as well as traditional accounts of the classical problem size effect in simple arithmetic (i.e. the finding that large problems are answered slower and less accurate than small problems). Empirical data supporting this view are still scarce. Methods: Data of 24 participants who performed a multiplication verification task with Arabic digits (e.g. 8 × 4 = 36 -true or false?) are reported. Behavioral (i.e. RT and errors) and EEG (i.e. ERP) measures were recorded in parallel. We provide evidence for neighborhood-consistency effects in the verification of simple multiplication problems (e.g. 8 × 4). Behaviorally, we find that decade-consistent lures, which share their decade digit with the correct result (e.g. 36), are harder to reject than matched inconsistent lures, which differ in both digits from the correct result (e.g. 28). This neighborhood consistency effect in product verification is similar to recent observations in the production of multiplication results. With respect to event-related potentials we find significant differences for consistent compared to inconsistent lures in the N400 (increased negativity) and Late Positive Component (reduced positivity). In this respect consistency effects in our paradigm resemble lexico-semantic effects earlier found in simple arithmetic and in orthographic input processing. Our data suggest that neighborhood consistency effects in simple multiplication stem at least partly from central (lexico-semantic') stages of processing. These results are compatible with current models on the representation of simple multiplication facts -in particular with the Interacting Neighbors Model -and with the notion of decomposed representations of two-digit numbers in general.
Starting from the ®nding that currently phonological models of visual word processing predominate... more Starting from the ®nding that currently phonological models of visual word processing predominate, we examined what happened when important morphological information is disclosed in the orthography but not in the phonology. To do so, we made use of a peculiarity in Dutch. In this language, some forms of the present and the past tense of verbs are homophones or homographs. This allowed us to look at the power of orthographic and phonological cues to derive the tense of the verb. Two experiments showed that orthographic cues alone suce to recover the tense of the verb, and that this recovery does not take more time than tense recovery on the basis of a combination of orthographic and phonological cues. On the basis of these results, we conclude that orthographic cues in homophones are very ecient during silent reading. Our ®ndings, however, do not allow us to conclude whether this is due to a direct route from orthography to meaning, or to a specialised, morpho-syntactic back-up strategy elicited by certain sequences of letters.
The present study presents timed norms for 590 pictures in Belgian Dutch. We determined name agre... more The present study presents timed norms for 590 pictures in Belgian Dutch. We determined name agreement and response latencies. Furthermore, we assessed which factors influenced the naming latencies of the pictures. It appeared that age-of-acquisition, the H-statistic (an index of name agreement), and the number of syllables of the dominant response were significant predictors of the naming latencies. These results are discussed in comparison with previous findings.
Quarterly Journal of Experimental Psychology, 2008
A monitoring bias account is often used to explain speech error patterns that seem to be the resu... more A monitoring bias account is often used to explain speech error patterns that seem to be the result of an interactive language production system, like phonological influences on lexical selection errors. A biased monitor is suggested to detect and covertly correct certain errors more often than others. For instance, this account predicts that errors that are phonologically similar to intended words are harder to detect than those that are phonologically dissimilar. To test this, we tried to elicit phonological errors under the same conditions as those that show other kinds of lexical selection errors. In five experiments, we presented participants with high cloze probability sentence fragments followed by a picture that was semantically related, a homophone of a semantically related word, or phonologically related to the (implicit) last word of the sentence. All experiments elicited semantic completions or homophones of semantic completions, but none elicited phonological completion...
The present study presents timed norms for 590 pictures in Belgian Dutch. We determined name agre... more The present study presents timed norms for 590 pictures in Belgian Dutch. We determined name agreement and response latencies. Furthermore, we assessed which factors influenced the naming latencies of the pictures. It appeared that age-of-acquisition, the H-statistic (an index of name agreement), and the number of syllables of the dominant response were significant predictors of the naming latencies. These results are discussed in comparison with previous findings.
In a recent study with the Poffenberger paradigm, Brizzolara et al. reported longer estimates of ... more In a recent study with the Poffenberger paradigm, Brizzolara et al. reported longer estimates of interhemispheric transfer time (IHTT) for children aged 7 years than for adults. They interpreted this finding as evidence for incomplete functional maturity of the corpus callosum in young children. The present study was we were unable to replicate the age effect reported by Brizzolara et al. A closer look at the original study revealed that only 80 observations per child had been collected, which makes it probable that the larger IHTTs in 7-year-olds were caused by stimulus-response compatibility rather than by the lower efficiency of the corpus callosum during childhood years.
Uploads
Papers by Elie Ratinckx