Slide
Centre Interdisciplinaire
de Recherche et d’Innovation
en Cybersécurité et Société
de Recherche et d’Innovation
en Cybersécurité et Société
1.
Ouellet-Courtois, C.; Bouchard, S.; Giguère, C. -E.; Koszycki, D.; Lavoie, M. E.; Aardema, F.
Cognitive mechanisms of change in OCD: Inferential confusion, obsessive beliefs, and mindfulness across three randomized treatments Journal Article
In: Behaviour Research and Therapy, vol. 201, 2026, ISSN: 00057967 (ISSN).
Abstract | Links | BibTeX | Tags: adult, antidepressant agent, Anxiety disorder, article, behavior therapy, benzodiazepine, clinical outcome, clinical trial, cognition, cognitive behavioral therapy, Cognitive mechanisms of change, confusion, confusion (uncertainty), controlled study, Depression, exposure and response prevention, female, human, Humans, Implosive Therapy, inference based cognitive behavioral therapy, Inferential confusion, major clinical study, male, Middle Aged, mindfulness, mindfulness-based stress reduction, multicenter study, obsession, obsessive compulsive disorder, Obsessive-Compulsive Disorder, procedures, psychology, randomized controlled trial, risk factor, Sensitivity analysis, Therapy, treatment outcome, Young Adult
@article{ouellet-courtoisCognitiveMechanismsChange2026,
title = {Cognitive mechanisms of change in OCD: Inferential confusion, obsessive beliefs, and mindfulness across three randomized treatments},
author = {C. Ouellet-Courtois and S. Bouchard and C. -E. Giguère and D. Koszycki and M. E. Lavoie and F. Aardema},
url = {https://www.scopus.com/pages/publications/105034701697?origin=resultslist},
doi = {10.1016/j.brat.2026.105022},
issn = {00057967 (ISSN)},
year = {2026},
date = {2026-01-01},
journal = {Behaviour Research and Therapy},
volume = {201},
publisher = {Elsevier Ltd},
abstract = {Cognitive-behavioral therapy (CBT) with exposure and response prevention (ERP) is widely regarded as the gold-standard psychological treatment for obsessive–compulsive disorder (OCD). Inference-based cognitive behavioral therapy (I-CBT) represents a distinct cognitive approach that targets inferential confusion, defined as a reasoning process whereby imagined possibilities are treated as reflecting reality, without relying on deliberate exposure. The present study reports further mechanism-focused analyses from a previously published multicenter randomized controlled trial (Aardema et al., 2022; ClinicalTrials.gov Identifier: NCT01794156) comparing CBT with ERP, I-CBT, and mindfulness-based stress reduction (MBSR) for OCD. A total of 111 participants with a primary diagnosis of OCD were randomized to one of three treatment conditions. Across treatments, therapy was associated with significant reductions in inferential confusion and obsessive belief domains, whereas dispositional mindfulness did not show significant change. At the bivariate level, residualized changes in inferential confusion, obsessive belief domains, and mindfulness were associated with reductions in OCD symptoms. However, when examined concurrently using mixed-effects models, only reductions in inferential confusion accounted for unique symptom improvement over time. This association was consistent across modalities and remained robust after controlling for concurrent anxiety and depression. Sensitivity analyses indicated that psychotropic medication use did not account for this association; controlling for medication strengthened the independent contribution of inferential confusion (partial η2 ≈ .29). These findings indicate that inferential confusion was independently associated with symptom improvement in OCD across therapeutic approaches. © 2026 Elsevier Ltd},
keywords = {adult, antidepressant agent, Anxiety disorder, article, behavior therapy, benzodiazepine, clinical outcome, clinical trial, cognition, cognitive behavioral therapy, Cognitive mechanisms of change, confusion, confusion (uncertainty), controlled study, Depression, exposure and response prevention, female, human, Humans, Implosive Therapy, inference based cognitive behavioral therapy, Inferential confusion, major clinical study, male, Middle Aged, mindfulness, mindfulness-based stress reduction, multicenter study, obsession, obsessive compulsive disorder, Obsessive-Compulsive Disorder, procedures, psychology, randomized controlled trial, risk factor, Sensitivity analysis, Therapy, treatment outcome, Young Adult},
pubstate = {published},
tppubtype = {article}
}
Cognitive-behavioral therapy (CBT) with exposure and response prevention (ERP) is widely regarded as the gold-standard psychological treatment for obsessive–compulsive disorder (OCD). Inference-based cognitive behavioral therapy (I-CBT) represents a distinct cognitive approach that targets inferential confusion, defined as a reasoning process whereby imagined possibilities are treated as reflecting reality, without relying on deliberate exposure. The present study reports further mechanism-focused analyses from a previously published multicenter randomized controlled trial (Aardema et al., 2022; ClinicalTrials.gov Identifier: NCT01794156) comparing CBT with ERP, I-CBT, and mindfulness-based stress reduction (MBSR) for OCD. A total of 111 participants with a primary diagnosis of OCD were randomized to one of three treatment conditions. Across treatments, therapy was associated with significant reductions in inferential confusion and obsessive belief domains, whereas dispositional mindfulness did not show significant change. At the bivariate level, residualized changes in inferential confusion, obsessive belief domains, and mindfulness were associated with reductions in OCD symptoms. However, when examined concurrently using mixed-effects models, only reductions in inferential confusion accounted for unique symptom improvement over time. This association was consistent across modalities and remained robust after controlling for concurrent anxiety and depression. Sensitivity analyses indicated that psychotropic medication use did not account for this association; controlling for medication strengthened the independent contribution of inferential confusion (partial η2 ≈ .29). These findings indicate that inferential confusion was independently associated with symptom improvement in OCD across therapeutic approaches. © 2026 Elsevier Ltd
2.
Richer, A.; Gingras, F.; Plouffe-Demers, M. -P.; Fiset, D.; Blais, C.
Is it pain, anger, disgust, or sadness? Individual differences in expectations of pain facial expressions. Journal Article
In: Emotion, vol. 25, no. 7, pp. 1750–1763, 2025, ISSN: 15283542 (ISSN).
Abstract | Links | BibTeX | Tags: adult, anger, article, awareness, confusion, disgust, emotion, emotionality, Emotions, Facial Expression, facial expressions confusion, Facial Recognition, Fear, female, human, human experiment, Humans, Individual differences, Individuality, joy, male, mental representation, Pain, pain facial expression, Pain facial expressions, perception, physiology, psychology, Reverse correlation, sadness, Social Perception, suprise, Young Adult
@article{richerItPainAnger2025a,
title = {Is it pain, anger, disgust, or sadness? Individual differences in expectations of pain facial expressions.},
author = {A. Richer and F. Gingras and M. -P. Plouffe-Demers and D. Fiset and C. Blais},
url = {https://www.scopus.com/pages/publications/105002303060?origin=resultslist},
doi = {10.1037/emo0001516},
issn = {15283542 (ISSN)},
year = {2025},
date = {2025-01-01},
journal = {Emotion},
volume = {25},
number = {7},
pages = {1750–1763},
publisher = {American Psychological Association},
abstract = {Humans rely on facial expressions to assess others’ affective states. However, pain facial expressions are poorly recognized and are often confused with other negative affective states, such as anger, disgust, sadness, and fear. Previous research has shown that individuals’ expectations about the appearance of pain facial expressions are not optimal and do not perfectly reflect the facial features typically observed in individuals expressing pain. In the present study, we verified if expectations about pain facial expressions are also suboptimal by overlapping with other affective states. We relied on two published data sets (data collected between 2017 and 2020) containing images representing the expectations of the appearance of pain facial expressions according to 162 White participants. We then asked an independent group of White participants (N = 60, 30 women},
keywords = {adult, anger, article, awareness, confusion, disgust, emotion, emotionality, Emotions, Facial Expression, facial expressions confusion, Facial Recognition, Fear, female, human, human experiment, Humans, Individual differences, Individuality, joy, male, mental representation, Pain, pain facial expression, Pain facial expressions, perception, physiology, psychology, Reverse correlation, sadness, Social Perception, suprise, Young Adult},
pubstate = {published},
tppubtype = {article}
}
Humans rely on facial expressions to assess others’ affective states. However, pain facial expressions are poorly recognized and are often confused with other negative affective states, such as anger, disgust, sadness, and fear. Previous research has shown that individuals’ expectations about the appearance of pain facial expressions are not optimal and do not perfectly reflect the facial features typically observed in individuals expressing pain. In the present study, we verified if expectations about pain facial expressions are also suboptimal by overlapping with other affective states. We relied on two published data sets (data collected between 2017 and 2020) containing images representing the expectations of the appearance of pain facial expressions according to 162 White participants. We then asked an independent group of White participants (N = 60, 30 women
3.
Richer, A.; Gingras, F.; Plouffe-Demers, M. -P.; Fiset, D.; Blais, C.
Is it pain, anger, disgust, or sadness? Individual differences in expectations of pain facial expressions. Journal Article
In: Emotion, vol. 25, no. 7, pp. 1750–1763, 2025, ISSN: 15283542 (ISSN).
Abstract | Links | BibTeX | Tags: adult, anger, article, awareness, confusion, disgust, emotion, emotionality, Emotions, Facial Expression, facial expressions confusion, Facial Recognition, Fear, female, human, human experiment, Humans, Individual differences, Individuality, joy, male, mental representation, Pain, pain facial expression, Pain facial expressions, perception, physiology, psychology, Reverse correlation, sadness, Social Perception, suprise, Young Adult
@article{richerItPainAnger2025b,
title = {Is it pain, anger, disgust, or sadness? Individual differences in expectations of pain facial expressions.},
author = {A. Richer and F. Gingras and M. -P. Plouffe-Demers and D. Fiset and C. Blais},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-105002303060&doi=10.1037%2Femo0001516&partnerID=40&md5=6b52952b00184d7e178ab041a2eaab88},
doi = {10.1037/emo0001516},
issn = {15283542 (ISSN)},
year = {2025},
date = {2025-01-01},
journal = {Emotion},
volume = {25},
number = {7},
pages = {1750–1763},
abstract = {Humans rely on facial expressions to assess others’ affective states. However, pain facial expressions are poorly recognized and are often confused with other negative affective states, such as anger, disgust, sadness, and fear. Previous research has shown that individuals’ expectations about the appearance of pain facial expressions are not optimal and do not perfectly reflect the facial features typically observed in individuals expressing pain. In the present study, we verified if expectations about pain facial expressions are also suboptimal by overlapping with other affective states. We relied on two published data sets (data collected between 2017 and 2020) containing images representing the expectations of the appearance of pain facial expressions according to 162 White participants. We then asked an independent group of White participants (N = 60, 30 women},
keywords = {adult, anger, article, awareness, confusion, disgust, emotion, emotionality, Emotions, Facial Expression, facial expressions confusion, Facial Recognition, Fear, female, human, human experiment, Humans, Individual differences, Individuality, joy, male, mental representation, Pain, pain facial expression, Pain facial expressions, perception, physiology, psychology, Reverse correlation, sadness, Social Perception, suprise, Young Adult},
pubstate = {published},
tppubtype = {article}
}
Humans rely on facial expressions to assess others’ affective states. However, pain facial expressions are poorly recognized and are often confused with other negative affective states, such as anger, disgust, sadness, and fear. Previous research has shown that individuals’ expectations about the appearance of pain facial expressions are not optimal and do not perfectly reflect the facial features typically observed in individuals expressing pain. In the present study, we verified if expectations about pain facial expressions are also suboptimal by overlapping with other affective states. We relied on two published data sets (data collected between 2017 and 2020) containing images representing the expectations of the appearance of pain facial expressions according to 162 White participants. We then asked an independent group of White participants (N = 60, 30 women
4.
Jack, R. E.; Blais, C.; Scheepers, C.; Schyns, P. G.; Caldara, R.
Cultural Confusions Show that Facial Expressions Are Not Universal Journal Article
In: Current Biology, vol. 19, no. 18, pp. 1543–1548, 2009, ISSN: 09609822 (ISSN).
Abstract | Links | BibTeX | Tags: adult, article, confusion, Cross-Cultural Comparison, cultural anthropology, Cultural Characteristics, cultural factor, Culture, emotion, Emotions, ethnology, eye movement, Eye movements, Facial Expression, Far East, female, human, human relation, Humans, Interpersonal Relations, male, Photic Stimulation, photostimulation, recognition, Recognition (Psychology), SYSNEURO, Western World
@article{jack_cultural_2009,
title = {Cultural Confusions Show that Facial Expressions Are Not Universal},
author = {R. E. Jack and C. Blais and C. Scheepers and P. G. Schyns and R. Caldara},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-70349289081&doi=10.1016%2fj.cub.2009.07.051&partnerID=40&md5=aedea29c81d3dcc7498c634bf1044e53},
doi = {10.1016/j.cub.2009.07.051},
issn = {09609822 (ISSN)},
year = {2009},
date = {2009-01-01},
journal = {Current Biology},
volume = {19},
number = {18},
pages = {1543–1548},
abstract = {Central to all human interaction is the mutual understanding of emotions, achieved primarily by a set of biologically rooted social signals evolved for this purpose-facial expressions of emotion. Although facial expressions are widely considered to be the universal language of emotion [1-3], some negative facial expressions consistently elicit lower recognition levels among Eastern compared to Western groups (see [4] for a meta-analysis and [5, 6] for review). Here, focusing on the decoding of facial expression signals, we merge behavioral and computational analyses with novel spatiotemporal analyses of eye movements, showing that Eastern observers use a culture-specific decoding strategy that is inadequate to reliably distinguish universal facial expressions of "fear" and "disgust." Rather than distributing their fixations evenly across the face as Westerners do, Eastern observers persistently fixate the eye region. Using a model information sampler, we demonstrate that by persistently fixating the eyes, Eastern observers sample ambiguous information, thus causing significant confusion. Our results question the universality of human facial expressions of emotion, highlighting their true complexity, with critical consequences for cross-cultural communication and globalization. © 2009 Elsevier Ltd. All rights reserved.},
keywords = {adult, article, confusion, Cross-Cultural Comparison, cultural anthropology, Cultural Characteristics, cultural factor, Culture, emotion, Emotions, ethnology, eye movement, Eye movements, Facial Expression, Far East, female, human, human relation, Humans, Interpersonal Relations, male, Photic Stimulation, photostimulation, recognition, Recognition (Psychology), SYSNEURO, Western World},
pubstate = {published},
tppubtype = {article}
}
Central to all human interaction is the mutual understanding of emotions, achieved primarily by a set of biologically rooted social signals evolved for this purpose-facial expressions of emotion. Although facial expressions are widely considered to be the universal language of emotion [1-3], some negative facial expressions consistently elicit lower recognition levels among Eastern compared to Western groups (see [4] for a meta-analysis and [5, 6] for review). Here, focusing on the decoding of facial expression signals, we merge behavioral and computational analyses with novel spatiotemporal analyses of eye movements, showing that Eastern observers use a culture-specific decoding strategy that is inadequate to reliably distinguish universal facial expressions of "fear" and "disgust." Rather than distributing their fixations evenly across the face as Westerners do, Eastern observers persistently fixate the eye region. Using a model information sampler, we demonstrate that by persistently fixating the eyes, Eastern observers sample ambiguous information, thus causing significant confusion. Our results question the universality of human facial expressions of emotion, highlighting their true complexity, with critical consequences for cross-cultural communication and globalization. © 2009 Elsevier Ltd. All rights reserved.
5.
Jack, R. E.; Blais, C.; Scheepers, C.; Schyns, P. G.; Caldara, R.
Cultural Confusions Show that Facial Expressions Are Not Universal Journal Article
In: Current Biology, vol. 19, no. 18, pp. 1543–1548, 2009, ISSN: 09609822 (ISSN).
Abstract | Links | BibTeX | Tags: adult, article, confusion, Cross-Cultural Comparison, cultural anthropology, Cultural Characteristics, cultural factor, Culture, emotion, Emotions, ethnology, eye movement, Eye movements, Facial Expression, Far East, female, human, human relation, Humans, Interpersonal Relations, male, Photic Stimulation, photostimulation, recognition, Recognition (Psychology), SYSNEURO, Western World
@article{jackCulturalConfusionsShow2009,
title = {Cultural Confusions Show that Facial Expressions Are Not Universal},
author = {R. E. Jack and C. Blais and C. Scheepers and P. G. Schyns and R. Caldara},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-70349289081&doi=10.1016%2fj.cub.2009.07.051&partnerID=40&md5=aedea29c81d3dcc7498c634bf1044e53},
doi = {10.1016/j.cub.2009.07.051},
issn = {09609822 (ISSN)},
year = {2009},
date = {2009-01-01},
journal = {Current Biology},
volume = {19},
number = {18},
pages = {1543–1548},
abstract = {Central to all human interaction is the mutual understanding of emotions, achieved primarily by a set of biologically rooted social signals evolved for this purpose-facial expressions of emotion. Although facial expressions are widely considered to be the universal language of emotion [1-3], some negative facial expressions consistently elicit lower recognition levels among Eastern compared to Western groups (see [4] for a meta-analysis and [5, 6] for review). Here, focusing on the decoding of facial expression signals, we merge behavioral and computational analyses with novel spatiotemporal analyses of eye movements, showing that Eastern observers use a culture-specific decoding strategy that is inadequate to reliably distinguish universal facial expressions of "fear" and "disgust." Rather than distributing their fixations evenly across the face as Westerners do, Eastern observers persistently fixate the eye region. Using a model information sampler, we demonstrate that by persistently fixating the eyes, Eastern observers sample ambiguous information, thus causing significant confusion. Our results question the universality of human facial expressions of emotion, highlighting their true complexity, with critical consequences for cross-cultural communication and globalization. © 2009 Elsevier Ltd. All rights reserved.},
keywords = {adult, article, confusion, Cross-Cultural Comparison, cultural anthropology, Cultural Characteristics, cultural factor, Culture, emotion, Emotions, ethnology, eye movement, Eye movements, Facial Expression, Far East, female, human, human relation, Humans, Interpersonal Relations, male, Photic Stimulation, photostimulation, recognition, Recognition (Psychology), SYSNEURO, Western World},
pubstate = {published},
tppubtype = {article}
}
Central to all human interaction is the mutual understanding of emotions, achieved primarily by a set of biologically rooted social signals evolved for this purpose-facial expressions of emotion. Although facial expressions are widely considered to be the universal language of emotion [1-3], some negative facial expressions consistently elicit lower recognition levels among Eastern compared to Western groups (see [4] for a meta-analysis and [5, 6] for review). Here, focusing on the decoding of facial expression signals, we merge behavioral and computational analyses with novel spatiotemporal analyses of eye movements, showing that Eastern observers use a culture-specific decoding strategy that is inadequate to reliably distinguish universal facial expressions of "fear" and "disgust." Rather than distributing their fixations evenly across the face as Westerners do, Eastern observers persistently fixate the eye region. Using a model information sampler, we demonstrate that by persistently fixating the eyes, Eastern observers sample ambiguous information, thus causing significant confusion. Our results question the universality of human facial expressions of emotion, highlighting their true complexity, with critical consequences for cross-cultural communication and globalization. © 2009 Elsevier Ltd. All rights reserved.
6.
Fiset, D.; Gosselin, F.; Blais, C.; Arguin, M.
Inducing letter-by-letter dyslexia in normal readers Journal Article
In: Journal of Cognitive Neuroscience, vol. 18, no. 9, pp. 1466–1476, 2006, ISSN: 0898929X.
Abstract | Links | BibTeX | Tags: Acquired, adult, analysis of variance, article, Brain Damage, Chronic, clinical feature, confusion, Contrast Sensitivity, controlled study, Dyslexia, Functional Laterality, human, human experiment, Humans, Infarction, male, Mental Processes, parallel design, Pattern Recognition, Photic Stimulation, Posterior Cerebral Artery, priority journal, reaction time, Reading, Reference Values, spatial frequency discrimination, Visual, visual discrimination, Visual Perception, visual system, word recognition
@article{fiset_inducing_2006,
title = {Inducing letter-by-letter dyslexia in normal readers},
author = {D. Fiset and F. Gosselin and C. Blais and M. Arguin},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-33749435964&doi=10.1162%2fjocn.2006.18.9.1466&partnerID=40&md5=edc961f6e18a7de0811cbc0e7ce9be1d},
doi = {10.1162/jocn.2006.18.9.1466},
issn = {0898929X},
year = {2006},
date = {2006-01-01},
journal = {Journal of Cognitive Neuroscience},
volume = {18},
number = {9},
pages = {1466–1476},
abstract = {Letter-by-letter (LBL) dyslexia is an acquired reading disorder characterized by very slow reading and a large linear word length effect. This suggests the use of a sequential LBL strategy, in sharp contrast with the parallel letter processing used by normal subjects. Recently, we have proposed that the reading difficulty of LBL dyslexics is due to a deficit in discriminating visually similar letters based on parallel letter processing [Arguin, M., Fiset, S., & Bub, D. Sequential and parallel letter processing in letter-by-letter dyslexia. Cognitive Neuropsychology, 19, 535-555, 2002]. The visual mechanisms underlying this deficit and the LBL strategy, however, are still unknown. In this article, we propose that LBL dyslexic patients have lost the ability to use, for parallel letter processing, the optimal spatial frequency band for letter and word recognition. We claim that, instead, they rely on lower spatial frequencies for parallel processing, that these lower spatial frequencies produce confusions between visually similar letters, and that the LBL compensatory strategy allows them to extract higher spatial frequencies. The LBL strategy would thus increase the spatial resolution of the visual system, effectively resolving the issue pertaining to between-letter similarity. In Experiments 1 and 2, we succeeded in replicating the main features characterizing LBL dyslexia by having normal individuals read low-contrast, high-pass-filtered words. Experiment 3, conducted in LBL dyslexic L.H., shows that, indeed, the letter confusability effect is based on low spatial frequencies, whereas this effect was not supported by high spatial frequencies. © 2006 Massachusetts Institute of Technology.},
keywords = {Acquired, adult, analysis of variance, article, Brain Damage, Chronic, clinical feature, confusion, Contrast Sensitivity, controlled study, Dyslexia, Functional Laterality, human, human experiment, Humans, Infarction, male, Mental Processes, parallel design, Pattern Recognition, Photic Stimulation, Posterior Cerebral Artery, priority journal, reaction time, Reading, Reference Values, spatial frequency discrimination, Visual, visual discrimination, Visual Perception, visual system, word recognition},
pubstate = {published},
tppubtype = {article}
}
Letter-by-letter (LBL) dyslexia is an acquired reading disorder characterized by very slow reading and a large linear word length effect. This suggests the use of a sequential LBL strategy, in sharp contrast with the parallel letter processing used by normal subjects. Recently, we have proposed that the reading difficulty of LBL dyslexics is due to a deficit in discriminating visually similar letters based on parallel letter processing [Arguin, M., Fiset, S., & Bub, D. Sequential and parallel letter processing in letter-by-letter dyslexia. Cognitive Neuropsychology, 19, 535-555, 2002]. The visual mechanisms underlying this deficit and the LBL strategy, however, are still unknown. In this article, we propose that LBL dyslexic patients have lost the ability to use, for parallel letter processing, the optimal spatial frequency band for letter and word recognition. We claim that, instead, they rely on lower spatial frequencies for parallel processing, that these lower spatial frequencies produce confusions between visually similar letters, and that the LBL compensatory strategy allows them to extract higher spatial frequencies. The LBL strategy would thus increase the spatial resolution of the visual system, effectively resolving the issue pertaining to between-letter similarity. In Experiments 1 and 2, we succeeded in replicating the main features characterizing LBL dyslexia by having normal individuals read low-contrast, high-pass-filtered words. Experiment 3, conducted in LBL dyslexic L.H., shows that, indeed, the letter confusability effect is based on low spatial frequencies, whereas this effect was not supported by high spatial frequencies. © 2006 Massachusetts Institute of Technology.
7.
Fiset, D.; Gosselin, F.; Blais, C.; Arguin, M.
Inducing letter-by-letter dyslexia in normal readers Journal Article
In: Journal of Cognitive Neuroscience, vol. 18, no. 9, pp. 1466–1476, 2006, ISSN: 0898929X.
Abstract | Links | BibTeX | Tags: Acquired, adult, analysis of variance, article, Brain Damage, Chronic, clinical feature, confusion, Contrast Sensitivity, controlled study, Dyslexia, Functional Laterality, human, human experiment, Humans, Infarction, male, Mental Processes, parallel design, Pattern Recognition, Photic Stimulation, Posterior Cerebral Artery, priority journal, reaction time, Reading, Reference Values, spatial frequency discrimination, Visual, visual discrimination, Visual Perception, visual system, word recognition
@article{fisetInducingLetterbyletterDyslexia2006,
title = {Inducing letter-by-letter dyslexia in normal readers},
author = {D. Fiset and F. Gosselin and C. Blais and M. Arguin},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-33749435964&doi=10.1162%2fjocn.2006.18.9.1466&partnerID=40&md5=edc961f6e18a7de0811cbc0e7ce9be1d},
doi = {10.1162/jocn.2006.18.9.1466},
issn = {0898929X},
year = {2006},
date = {2006-01-01},
journal = {Journal of Cognitive Neuroscience},
volume = {18},
number = {9},
pages = {1466–1476},
abstract = {Letter-by-letter (LBL) dyslexia is an acquired reading disorder characterized by very slow reading and a large linear word length effect. This suggests the use of a sequential LBL strategy, in sharp contrast with the parallel letter processing used by normal subjects. Recently, we have proposed that the reading difficulty of LBL dyslexics is due to a deficit in discriminating visually similar letters based on parallel letter processing [Arguin, M., Fiset, S., & Bub, D. Sequential and parallel letter processing in letter-by-letter dyslexia. Cognitive Neuropsychology, 19, 535-555, 2002]. The visual mechanisms underlying this deficit and the LBL strategy, however, are still unknown. In this article, we propose that LBL dyslexic patients have lost the ability to use, for parallel letter processing, the optimal spatial frequency band for letter and word recognition. We claim that, instead, they rely on lower spatial frequencies for parallel processing, that these lower spatial frequencies produce confusions between visually similar letters, and that the LBL compensatory strategy allows them to extract higher spatial frequencies. The LBL strategy would thus increase the spatial resolution of the visual system, effectively resolving the issue pertaining to between-letter similarity. In Experiments 1 and 2, we succeeded in replicating the main features characterizing LBL dyslexia by having normal individuals read low-contrast, high-pass-filtered words. Experiment 3, conducted in LBL dyslexic L.H., shows that, indeed, the letter confusability effect is based on low spatial frequencies, whereas this effect was not supported by high spatial frequencies. © 2006 Massachusetts Institute of Technology.},
keywords = {Acquired, adult, analysis of variance, article, Brain Damage, Chronic, clinical feature, confusion, Contrast Sensitivity, controlled study, Dyslexia, Functional Laterality, human, human experiment, Humans, Infarction, male, Mental Processes, parallel design, Pattern Recognition, Photic Stimulation, Posterior Cerebral Artery, priority journal, reaction time, Reading, Reference Values, spatial frequency discrimination, Visual, visual discrimination, Visual Perception, visual system, word recognition},
pubstate = {published},
tppubtype = {article}
}
Letter-by-letter (LBL) dyslexia is an acquired reading disorder characterized by very slow reading and a large linear word length effect. This suggests the use of a sequential LBL strategy, in sharp contrast with the parallel letter processing used by normal subjects. Recently, we have proposed that the reading difficulty of LBL dyslexics is due to a deficit in discriminating visually similar letters based on parallel letter processing [Arguin, M., Fiset, S., & Bub, D. Sequential and parallel letter processing in letter-by-letter dyslexia. Cognitive Neuropsychology, 19, 535-555, 2002]. The visual mechanisms underlying this deficit and the LBL strategy, however, are still unknown. In this article, we propose that LBL dyslexic patients have lost the ability to use, for parallel letter processing, the optimal spatial frequency band for letter and word recognition. We claim that, instead, they rely on lower spatial frequencies for parallel processing, that these lower spatial frequencies produce confusions between visually similar letters, and that the LBL compensatory strategy allows them to extract higher spatial frequencies. The LBL strategy would thus increase the spatial resolution of the visual system, effectively resolving the issue pertaining to between-letter similarity. In Experiments 1 and 2, we succeeded in replicating the main features characterizing LBL dyslexia by having normal individuals read low-contrast, high-pass-filtered words. Experiment 3, conducted in LBL dyslexic L.H., shows that, indeed, the letter confusability effect is based on low spatial frequencies, whereas this effect was not supported by high spatial frequencies. © 2006 Massachusetts Institute of Technology.