Slide
Centre Interdisciplinaire
de Recherche et d’Innovation
en Cybersécurité et Société
de Recherche et d’Innovation
en Cybersécurité et Société
1.
Charbonneau, I.; Guérette, J.; Cormier, S.; Blais, C.; Lalonde-Beaudoin, G.; Smith, F. W.; Fiset, D.
The role of spatial frequencies for facial pain categorization Article de journal
Dans: Scientific Reports, vol. 11, no 1, 2021, ISSN: 20452322, (Publisher: Nature Research).
Résumé | Liens | BibTeX | Étiquettes: Adolescent, adult, Classification, Distance Perception, emotion, Emotions, Face, face pain, Facial Expression, Facial Pain, Facial Recognition, female, human, Humans, Knowledge, male, Normal Distribution, Pattern Recognition, procedures, psychology, Psychophysics, recognition, reproducibility, Reproducibility of Results, Visual, Young Adult
@article{charbonneau_role_2021,
title = {The role of spatial frequencies for facial pain categorization},
author = {I. Charbonneau and J. Guérette and S. Cormier and C. Blais and G. Lalonde-Beaudoin and F. W. Smith and D. Fiset},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85111138273&doi=10.1038%2fs41598-021-93776-7&partnerID=40&md5=d759d0218de65fce371bb51d7f2593d8},
doi = {10.1038/s41598-021-93776-7},
issn = {20452322},
year = {2021},
date = {2021-01-01},
journal = {Scientific Reports},
volume = {11},
number = {1},
abstract = {Studies on low-level visual information underlying pain categorization have led to inconsistent findings. Some show an advantage for low spatial frequency information (SFs) and others a preponderance of mid SFs. This study aims to clarify this gap in knowledge since these results have different theoretical and practical implications, such as how far away an observer can be in order to categorize pain. This study addresses this question by using two complementary methods: a data-driven method without a priori expectations about the most useful SFs for pain recognition and a more ecological method that simulates the distance of stimuli presentation. We reveal a broad range of important SFs for pain recognition starting from low to relatively high SFs and showed that performance is optimal in a short to medium distance (1.2–4.8 m) but declines significantly when mid SFs are no longer available. This study reconciles previous results that show an advantage of LSFs over HSFs when using arbitrary cutoffs, but above all reveal the prominent role of mid-SFs for pain recognition across two complementary experimental tasks. © 2021, The Author(s).},
note = {Publisher: Nature Research},
keywords = {Adolescent, adult, Classification, Distance Perception, emotion, Emotions, Face, face pain, Facial Expression, Facial Pain, Facial Recognition, female, human, Humans, Knowledge, male, Normal Distribution, Pattern Recognition, procedures, psychology, Psychophysics, recognition, reproducibility, Reproducibility of Results, Visual, Young Adult},
pubstate = {published},
tppubtype = {article}
}
Studies on low-level visual information underlying pain categorization have led to inconsistent findings. Some show an advantage for low spatial frequency information (SFs) and others a preponderance of mid SFs. This study aims to clarify this gap in knowledge since these results have different theoretical and practical implications, such as how far away an observer can be in order to categorize pain. This study addresses this question by using two complementary methods: a data-driven method without a priori expectations about the most useful SFs for pain recognition and a more ecological method that simulates the distance of stimuli presentation. We reveal a broad range of important SFs for pain recognition starting from low to relatively high SFs and showed that performance is optimal in a short to medium distance (1.2–4.8 m) but declines significantly when mid SFs are no longer available. This study reconciles previous results that show an advantage of LSFs over HSFs when using arbitrary cutoffs, but above all reveal the prominent role of mid-SFs for pain recognition across two complementary experimental tasks. © 2021, The Author(s).
2.
Saumure, C.; Plouffe-Demers, M. -P.; Estéphan, A.; Fiset, D.; Blais, C.
The use of visual information in the recognition of posed and spontaneous facial expressions Article de journal
Dans: Journal of Vision, vol. 18, no 9, p. 1–15, 2018, ISSN: 15347362, (Publisher: Association for Research in Vision and Ophthalmology Inc.).
Résumé | Liens | BibTeX | Étiquettes: association, Cues, emotion, Emotions, Facial Expression, Facial Recognition, female, happiness, human, Humans, male, Pattern Recognition, physiology, Visual, Young Adult
@article{saumure_use_2018,
title = {The use of visual information in the recognition of posed and spontaneous facial expressions},
author = {C. Saumure and M. -P. Plouffe-Demers and A. Estéphan and D. Fiset and C. Blais},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85054591286&doi=10.1167%2f18.9.21&partnerID=40&md5=9d2396b70438842c089a36f6a499f734},
doi = {10.1167/18.9.21},
issn = {15347362},
year = {2018},
date = {2018-01-01},
journal = {Journal of Vision},
volume = {18},
number = {9},
pages = {1–15},
abstract = {Recognizing facial expressions is crucial for the success of social interactions, and the visual processes underlying this ability have been the subject of many studies in the field of face perception. Nevertheless, the stimuli used in the majority of these studies consist of facial expressions that were produced on request rather than spontaneously induced. In the present study, we directly compared the visual strategies underlying the recognition of posed and spontaneous expressions of happiness, disgust, surprise, and sadness. We used the Bubbles method with pictures of the same individuals spontaneously expressing an emotion or posing with an expression on request. Two key findings were obtained: Visual strategies were less systematic with spontaneous than with posed expressions, suggesting a higher heterogeneity in the useful facial cues across identities; and with spontaneous expressions, the relative reliance on the mouth and eyes areas was more evenly distributed, contrasting with the higher reliance on the mouth compared to the eyes area observed with posed expressions. © 2018 The Authors.},
note = {Publisher: Association for Research in Vision and Ophthalmology Inc.},
keywords = {association, Cues, emotion, Emotions, Facial Expression, Facial Recognition, female, happiness, human, Humans, male, Pattern Recognition, physiology, Visual, Young Adult},
pubstate = {published},
tppubtype = {article}
}
Recognizing facial expressions is crucial for the success of social interactions, and the visual processes underlying this ability have been the subject of many studies in the field of face perception. Nevertheless, the stimuli used in the majority of these studies consist of facial expressions that were produced on request rather than spontaneously induced. In the present study, we directly compared the visual strategies underlying the recognition of posed and spontaneous expressions of happiness, disgust, surprise, and sadness. We used the Bubbles method with pictures of the same individuals spontaneously expressing an emotion or posing with an expression on request. Two key findings were obtained: Visual strategies were less systematic with spontaneous than with posed expressions, suggesting a higher heterogeneity in the useful facial cues across identities; and with spontaneous expressions, the relative reliance on the mouth and eyes areas was more evenly distributed, contrasting with the higher reliance on the mouth compared to the eyes area observed with posed expressions. © 2018 The Authors.
3.
Estéphan, A.; Fiset, D.; Saumure, C.; Plouffe-Demers, M. -P.; Zhang, Y.; Sun, D.; Blais, C.
Time course of cultural differences in spatial frequency use for face identification Article de journal
Dans: Scientific Reports, vol. 8, no 1, 2018, ISSN: 20452322, (Publisher: Nature Publishing Group).
Résumé | Liens | BibTeX | Étiquettes: adult, article, Asian Continental Ancestry Group, attention, Canada, Caucasian, European Continental Ancestry Group, eye movement, Eye movements, Facial Recognition, female, financial management, human, human experiment, Humans, male, Pattern Recognition, physiology, stimulus, Visual, visual information, Young Adult
@article{estephan_time_2018,
title = {Time course of cultural differences in spatial frequency use for face identification},
author = {A. Estéphan and D. Fiset and C. Saumure and M. -P. Plouffe-Demers and Y. Zhang and D. Sun and C. Blais},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85041296131&doi=10.1038%2fs41598-018-19971-1&partnerID=40&md5=b9e70f2d9ac7c641171bd6e450316846},
doi = {10.1038/s41598-018-19971-1},
issn = {20452322},
year = {2018},
date = {2018-01-01},
journal = {Scientific Reports},
volume = {8},
number = {1},
abstract = {Several previous studies of eye movements have put forward that, during face recognition, Easterners spread their attention across a greater part of their visual field than Westerners. Recently, we found that culture's effect on the perception of faces reaches mechanisms deeper than eye movements, therefore affecting the very nature of information sampled by the visual system: That is, Westerners globally rely more than Easterners on fine-grained visual information (i.e. high spatial frequencies; SFs), whereas Easterners rely more on coarse-grained visual information (i.e. low SFs). These findings suggest that culture influences basic visual processes; however, the temporal onset and dynamics of these culturespecific perceptual differences are still unknown. Here, we investigate the time course of SF use in Western Caucasian (Canadian) and East Asian (Chinese) observers during a face identification task. Firstly, our results confirm that Easterners use relatively lower SFs than Westerners, while the latter use relatively higher SFs. More importantly, our results indicate that these differences arise as early as 34 ms after stimulus onset, and remain stable through time. Our research supports the hypothesis that Westerners and Easterners initially rely on different types of visual information during face processing. © The Author(s) 2018.},
note = {Publisher: Nature Publishing Group},
keywords = {adult, article, Asian Continental Ancestry Group, attention, Canada, Caucasian, European Continental Ancestry Group, eye movement, Eye movements, Facial Recognition, female, financial management, human, human experiment, Humans, male, Pattern Recognition, physiology, stimulus, Visual, visual information, Young Adult},
pubstate = {published},
tppubtype = {article}
}
Several previous studies of eye movements have put forward that, during face recognition, Easterners spread their attention across a greater part of their visual field than Westerners. Recently, we found that culture's effect on the perception of faces reaches mechanisms deeper than eye movements, therefore affecting the very nature of information sampled by the visual system: That is, Westerners globally rely more than Easterners on fine-grained visual information (i.e. high spatial frequencies; SFs), whereas Easterners rely more on coarse-grained visual information (i.e. low SFs). These findings suggest that culture influences basic visual processes; however, the temporal onset and dynamics of these culturespecific perceptual differences are still unknown. Here, we investigate the time course of SF use in Western Caucasian (Canadian) and East Asian (Chinese) observers during a face identification task. Firstly, our results confirm that Easterners use relatively lower SFs than Westerners, while the latter use relatively higher SFs. More importantly, our results indicate that these differences arise as early as 34 ms after stimulus onset, and remain stable through time. Our research supports the hypothesis that Westerners and Easterners initially rely on different types of visual information during face processing. © The Author(s) 2018.
4.
Royer, J.; Willenbockel, V.; Blais, C.; Gosselin, F.; Lafortune, S.; Leclerc, J.; Fiset, D.
The influence of natural contour and face size on the spatial frequency tuning for identifying upright and inverted faces Article de journal
Dans: Psychological Research, vol. 81, no 1, p. 13–23, 2017, ISSN: 03400727, (Publisher: Springer Verlag).
Résumé | Liens | BibTeX | Étiquettes: adult, anatomy and histology, Face, female, Form Perception, human, Humans, male, Pattern Recognition, Visual
@article{royer_influence_2017,
title = {The influence of natural contour and face size on the spatial frequency tuning for identifying upright and inverted faces},
author = {J. Royer and V. Willenbockel and C. Blais and F. Gosselin and S. Lafortune and J. Leclerc and D. Fiset},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84952682687&doi=10.1007%2fs00426-015-0740-3&partnerID=40&md5=338e8de567bcb78a38dc37e35297d569},
doi = {10.1007/s00426-015-0740-3},
issn = {03400727},
year = {2017},
date = {2017-01-01},
journal = {Psychological Research},
volume = {81},
number = {1},
pages = {13–23},
abstract = {It has previously been proposed that holistic face processing is based on low spatial frequencies (SFs) whereas featural processing relies on higher SFs, a hypothesis still widespread in the face processing literature today (e.g. Peters et al. in Eur J Neurosci 37(9):1448–1457, 2013). Since upright faces are supposedly recognized through holistic processing and inverted faces, using features, it is easy to take the leap to suggest a qualitatively different SF tuning for the identification of upright and vs. inverted faces. However, two independent studies (e.g. Gaspar et al. in Vision Res 48(28):2817–2826, 2008; Willenbockel et al. in J Exp Psychol Human 36(1):122–135, 2010a) found the same SF tuning for both stimulus presentations. Since these authors used relatively small faces hiding the natural facial contour, it is possible that differences in the SF tuning for identifying upright and inverted faces were missed. The present study thus revisits the SF tuning for upright and inverted faces face identification using the SF Bubbles technique. Our results still indicate that the same SFs are involved in both upright and inverted face recognition regardless of these additional parameters (contour and size), thus contrasting with previous data obtained using different methods (e.g. Oruc and Barton in J Vis 10(12):20, 1–12, 2010). The possible reasons subtending this divergence are discussed. © 2015, Springer-Verlag Berlin Heidelberg.},
note = {Publisher: Springer Verlag},
keywords = {adult, anatomy and histology, Face, female, Form Perception, human, Humans, male, Pattern Recognition, Visual},
pubstate = {published},
tppubtype = {article}
}
It has previously been proposed that holistic face processing is based on low spatial frequencies (SFs) whereas featural processing relies on higher SFs, a hypothesis still widespread in the face processing literature today (e.g. Peters et al. in Eur J Neurosci 37(9):1448–1457, 2013). Since upright faces are supposedly recognized through holistic processing and inverted faces, using features, it is easy to take the leap to suggest a qualitatively different SF tuning for the identification of upright and vs. inverted faces. However, two independent studies (e.g. Gaspar et al. in Vision Res 48(28):2817–2826, 2008; Willenbockel et al. in J Exp Psychol Human 36(1):122–135, 2010a) found the same SF tuning for both stimulus presentations. Since these authors used relatively small faces hiding the natural facial contour, it is possible that differences in the SF tuning for identifying upright and inverted faces were missed. The present study thus revisits the SF tuning for upright and inverted faces face identification using the SF Bubbles technique. Our results still indicate that the same SFs are involved in both upright and inverted face recognition regardless of these additional parameters (contour and size), thus contrasting with previous data obtained using different methods (e.g. Oruc and Barton in J Vis 10(12):20, 1–12, 2010). The possible reasons subtending this divergence are discussed. © 2015, Springer-Verlag Berlin Heidelberg.
5.
Duncan, J.; Gosselin, F.; Cobarro, C.; Dugas, G.; Blais, C.; Fiset, D.
Orientations for the successful categorization of facial expressions and their link with facial features Article de journal
Dans: Journal of Vision, vol. 17, no 14, 2017, ISSN: 15347362, (Publisher: Association for Research in Vision and Ophthalmology Inc.).
Résumé | Liens | BibTeX | Étiquettes: emotion, Emotions, Face, Facial Expression, human, Humans, Orientation, Pattern Recognition, physiology, Spatial, spatial orientation, Visual
@article{duncan_orientations_2017,
title = {Orientations for the successful categorization of facial expressions and their link with facial features},
author = {J. Duncan and F. Gosselin and C. Cobarro and G. Dugas and C. Blais and D. Fiset},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85037872637&doi=10.1167%2f17.14.7&partnerID=40&md5=acba0f4300c354117878a5b87041ec5f},
doi = {10.1167/17.14.7},
issn = {15347362},
year = {2017},
date = {2017-01-01},
journal = {Journal of Vision},
volume = {17},
number = {14},
abstract = {Horizontal information was recently suggested to be crucial for face identification. In the present paper, we expand on this finding and investigate the role of orientations for all the basic facial expressions and neutrality. To this end, we developed orientation bubbles to quantify utilization of the orientation spectrum by the visual system in a facial expression categorization task. We first validated the procedure in Experiment 1 with a simple plaid-detection task. In Experiment 2, we used orientation bubbles to reveal the diagnostic-i.e., task relevant-orientations for the basic facial expressions and neutrality. Overall, we found that horizontal information was highly diagnostic for expressions- surprise excepted. We also found that utilization of horizontal information strongly predicted performance level in this task. Despite the recent surge of research on horizontals, the link with local features remains unexplored.We were thus also interested in investigating this link. In Experiment 3, location bubbles were used to reveal the diagnostic features for the basic facial expressions. Crucially, Experiments 2 and 3 were run in parallel on the same participants, in an interleaved fashion. This way, we were able to correlate individual orientation and local diagnostic profiles. Our results indicate that individual differences in horizontal tuning are best predicted by utilization of the eyes. © 2017 The Authors.},
note = {Publisher: Association for Research in Vision and Ophthalmology Inc.},
keywords = {emotion, Emotions, Face, Facial Expression, human, Humans, Orientation, Pattern Recognition, physiology, Spatial, spatial orientation, Visual},
pubstate = {published},
tppubtype = {article}
}
Horizontal information was recently suggested to be crucial for face identification. In the present paper, we expand on this finding and investigate the role of orientations for all the basic facial expressions and neutrality. To this end, we developed orientation bubbles to quantify utilization of the orientation spectrum by the visual system in a facial expression categorization task. We first validated the procedure in Experiment 1 with a simple plaid-detection task. In Experiment 2, we used orientation bubbles to reveal the diagnostic-i.e., task relevant-orientations for the basic facial expressions and neutrality. Overall, we found that horizontal information was highly diagnostic for expressions- surprise excepted. We also found that utilization of horizontal information strongly predicted performance level in this task. Despite the recent surge of research on horizontals, the link with local features remains unexplored.We were thus also interested in investigating this link. In Experiment 3, location bubbles were used to reveal the diagnostic features for the basic facial expressions. Crucially, Experiments 2 and 3 were run in parallel on the same participants, in an interleaved fashion. This way, we were able to correlate individual orientation and local diagnostic profiles. Our results indicate that individual differences in horizontal tuning are best predicted by utilization of the eyes. © 2017 The Authors.
6.
Daudelin-Peltier, C.; Forget, H.; Blais, C.; Deschênes, A.; Fiset, D.
The effect of acute social stress on the recognition of facial expression of emotions /631/378/2649 /631/378/1457 article Article de journal
Dans: Scientific Reports, vol. 7, no 1, 2017, ISSN: 20452322, (Publisher: Nature Publishing Group).
Résumé | Liens | BibTeX | Étiquettes: adult, Anxiety, clinical study, controlled study, disgust, evolutionary adaptation, Facial Expression, Facial Recognition, human, Humans, Hydrocortisone, male, mental stress, metabolism, monitoring, pathophysiology, Pattern Recognition, Photic Stimulation, photostimulation, physiology, Psychological, reaction time, social stress, Stress, Visual, Young Adult
@article{daudelin-peltier_effect_2017,
title = {The effect of acute social stress on the recognition of facial expression of emotions /631/378/2649 /631/378/1457 article},
author = {C. Daudelin-Peltier and H. Forget and C. Blais and A. Deschênes and D. Fiset},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85018189261&doi=10.1038%2fs41598-017-01053-3&partnerID=40&md5=4405225de4b80852d5d98a2fd2171812},
doi = {10.1038/s41598-017-01053-3},
issn = {20452322},
year = {2017},
date = {2017-01-01},
journal = {Scientific Reports},
volume = {7},
number = {1},
abstract = {This study investigates the effect of acute social stress on the recognition of facial expression of emotions in healthy young men. Participants underwent both a standardized psychosocial laboratory stressor (TSST-G) and a control condition. Then, they performed a homemade version of the facial expressions megamix. All six basic emotions were included in the task. First, our results show a systematic increase in the intensity threshold for disgust following stress, meaning that the participants' performance with this emotion was impaired. We suggest that this may reflect an adaptive coping mechanism where participants attempt to decrease their anxiety and protect themselves from a socio-evaluative threat. Second, our results show a systematic decrease in the intensity threshold for surprise, therefore positively affecting the participants' performance with that emotion. We suggest that the enhanced perception of surprise following the induction of social stress may be interpreted as an evolutionary adaptation, wherein being in a stressful environment increases the benefits of monitoring signals indicating the presence of a novel or threatening event. An alternative explanation may derive from the opposite nature of the facial expressions of disgust and surprise; the decreased recognition of disgust could therefore have fostered the propensity to perceive surprise. © 2017 The Author(s).},
note = {Publisher: Nature Publishing Group},
keywords = {adult, Anxiety, clinical study, controlled study, disgust, evolutionary adaptation, Facial Expression, Facial Recognition, human, Humans, Hydrocortisone, male, mental stress, metabolism, monitoring, pathophysiology, Pattern Recognition, Photic Stimulation, photostimulation, physiology, Psychological, reaction time, social stress, Stress, Visual, Young Adult},
pubstate = {published},
tppubtype = {article}
}
This study investigates the effect of acute social stress on the recognition of facial expression of emotions in healthy young men. Participants underwent both a standardized psychosocial laboratory stressor (TSST-G) and a control condition. Then, they performed a homemade version of the facial expressions megamix. All six basic emotions were included in the task. First, our results show a systematic increase in the intensity threshold for disgust following stress, meaning that the participants' performance with this emotion was impaired. We suggest that this may reflect an adaptive coping mechanism where participants attempt to decrease their anxiety and protect themselves from a socio-evaluative threat. Second, our results show a systematic decrease in the intensity threshold for surprise, therefore positively affecting the participants' performance with that emotion. We suggest that the enhanced perception of surprise following the induction of social stress may be interpreted as an evolutionary adaptation, wherein being in a stressful environment increases the benefits of monitoring signals indicating the presence of a novel or threatening event. An alternative explanation may derive from the opposite nature of the facial expressions of disgust and surprise; the decreased recognition of disgust could therefore have fostered the propensity to perceive surprise. © 2017 The Author(s).
7.
Royer, J.; Blais, C.; Barnabé-Lortie, V.; Carré, M.; Leclerc, J.; Fiset, D.
Efficient visual information for unfamiliar face matching despite viewpoint variations: It's not in the eyes! Article de journal
Dans: Vision Research, vol. 123, p. 33–40, 2016, ISSN: 00426989 (ISSN), (Publisher: Elsevier Ltd).
Résumé | Liens | BibTeX | Étiquettes: accuracy, adult, article, association, attention, Bubbles, Evoked Potentials, eye fixation, Face, face profile, face recognition, Facial Recognition, facies, female, Fixation, human, human experiment, Humans, Image analysis, Individual differences, male, Ocular, Pattern Recognition, Photic Stimulation, photostimulation, physiology, priority journal, procedures, Psychophysics, recognition, Recognition (Psychology), regression analysis, task performance, unfamiliar face matching, viewpoint variation, Viewpoint variations, Visual, visual discrimination, visual evoked potential, visual information, visual memory, visual stimulation, visual system parameters, Young Adult
@article{royer_efficient_2016,
title = {Efficient visual information for unfamiliar face matching despite viewpoint variations: It's not in the eyes!},
author = {J. Royer and C. Blais and V. Barnabé-Lortie and M. Carré and J. Leclerc and D. Fiset},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84968779426&doi=10.1016%2fj.visres.2016.04.004&partnerID=40&md5=4c63f6eea279f7322c9af23ae9ed22c1},
doi = {10.1016/j.visres.2016.04.004},
issn = {00426989 (ISSN)},
year = {2016},
date = {2016-01-01},
journal = {Vision Research},
volume = {123},
pages = {33–40},
abstract = {Faces are encountered in highly diverse angles in real-world settings. Despite this considerable diversity, most individuals are able to easily recognize familiar faces. The vast majority of studies in the field of face recognition have nonetheless focused almost exclusively on frontal views of faces. Indeed, a number of authors have investigated the diagnostic facial features for the recognition of frontal views of faces previously encoded in this same view. However, the nature of the information useful for identity matching when the encoded face and test face differ in viewing angle remains mostly unexplored. The present study addresses this issue using individual differences and bubbles, a method that pinpoints the facial features effectively used in a visual categorization task. Our results indicate that the use of features located in the center of the face, the lower left portion of the nose area and the center of the mouth, are significantly associated with individual efficiency to generalize a face's identity across different viewpoints. However, as faces become more familiar, the reliance on this area decreases, while the diagnosticity of the eye region increases. This suggests that a certain distinction can be made between the visual mechanisms subtending viewpoint invariance and face recognition in the case of unfamiliar face identification. Our results further support the idea that the eye area may only come into play when the face stimulus is particularly familiar to the observer. © 2016 Elsevier Ltd.},
note = {Publisher: Elsevier Ltd},
keywords = {accuracy, adult, article, association, attention, Bubbles, Evoked Potentials, eye fixation, Face, face profile, face recognition, Facial Recognition, facies, female, Fixation, human, human experiment, Humans, Image analysis, Individual differences, male, Ocular, Pattern Recognition, Photic Stimulation, photostimulation, physiology, priority journal, procedures, Psychophysics, recognition, Recognition (Psychology), regression analysis, task performance, unfamiliar face matching, viewpoint variation, Viewpoint variations, Visual, visual discrimination, visual evoked potential, visual information, visual memory, visual stimulation, visual system parameters, Young Adult},
pubstate = {published},
tppubtype = {article}
}
Faces are encountered in highly diverse angles in real-world settings. Despite this considerable diversity, most individuals are able to easily recognize familiar faces. The vast majority of studies in the field of face recognition have nonetheless focused almost exclusively on frontal views of faces. Indeed, a number of authors have investigated the diagnostic facial features for the recognition of frontal views of faces previously encoded in this same view. However, the nature of the information useful for identity matching when the encoded face and test face differ in viewing angle remains mostly unexplored. The present study addresses this issue using individual differences and bubbles, a method that pinpoints the facial features effectively used in a visual categorization task. Our results indicate that the use of features located in the center of the face, the lower left portion of the nose area and the center of the mouth, are significantly associated with individual efficiency to generalize a face's identity across different viewpoints. However, as faces become more familiar, the reliance on this area decreases, while the diagnosticity of the eye region increases. This suggests that a certain distinction can be made between the visual mechanisms subtending viewpoint invariance and face recognition in the case of unfamiliar face identification. Our results further support the idea that the eye area may only come into play when the face stimulus is particularly familiar to the observer. © 2016 Elsevier Ltd.
8.
Roy, C.; Blais, C.; Fiset, D.; Rainville, P.; Gosselin, F.
Efficient information for recognizing pain in facial expressions Article de journal
Dans: European Journal of Pain (United Kingdom), vol. 19, no 6, p. 852–860, 2015, ISSN: 10903801 (ISSN).
Résumé | Liens | BibTeX | Étiquettes: anger, article, association, Classification, Cues, disgust, emotion, Emotions, Facial Expression, Fear, female, happiness, human, human experiment, Humans, male, nociception, normal human, Pain, pain assessment, Pattern Recognition, Photic Stimulation, photostimulation, physiology, priority journal, procedures, random sample, reproducibility, Reproducibility of Results, sadness, statistical significance, Visual, visual information, visual stimulation
@article{roy_efficient_2015,
title = {Efficient information for recognizing pain in facial expressions},
author = {C. Roy and C. Blais and D. Fiset and P. Rainville and F. Gosselin},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84929122739&doi=10.1002%2fejp.676&partnerID=40&md5=027f6da7b6d5c98c86de6a07766fb83d},
doi = {10.1002/ejp.676},
issn = {10903801 (ISSN)},
year = {2015},
date = {2015-01-01},
journal = {European Journal of Pain (United Kingdom)},
volume = {19},
number = {6},
pages = {852–860},
abstract = {Background The face as a visual stimulus is a reliable source of information for judging the pain experienced by others. Until now, most studies investigating the facial expression of pain have used a descriptive method (i.e. Facial Action Coding System). However, the facial features that are relevant for the observer in the identification of the expression of pain remain largely unknown despite the strong medical impact that misjudging pain can have on patients' well-being. Methods Here, we investigated this question by applying the Bubbles method. Fifty healthy volunteers were asked to categorize facial expressions (the six basic emotions, pain and neutrality) displayed in stimuli obtained from a previously validated set and presented for 500 ms each. To determine the critical areas of the face used in this categorization task, the faces were partly masked based on random sampling of regions of the stimuli at different spatial frequency ranges. Results Results show that accurate pain discrimination relies mostly on the frown lines and the mouth. Finally, an ideal observer analysis indicated that the use of the frown lines in human observers could not be attributed to the objective 'informativeness' of this area. Conclusions Based on a recent study suggesting that this area codes for the affective dimension of pain, we propose that the visual system has evolved to focus primarily on the facial cues that signal the aversiveness of pain, consistent with the social role of facial expressions in the communication of potential threats. © 2015 European Pain Federation-EFIC®.},
keywords = {anger, article, association, Classification, Cues, disgust, emotion, Emotions, Facial Expression, Fear, female, happiness, human, human experiment, Humans, male, nociception, normal human, Pain, pain assessment, Pattern Recognition, Photic Stimulation, photostimulation, physiology, priority journal, procedures, random sample, reproducibility, Reproducibility of Results, sadness, statistical significance, Visual, visual information, visual stimulation},
pubstate = {published},
tppubtype = {article}
}
Background The face as a visual stimulus is a reliable source of information for judging the pain experienced by others. Until now, most studies investigating the facial expression of pain have used a descriptive method (i.e. Facial Action Coding System). However, the facial features that are relevant for the observer in the identification of the expression of pain remain largely unknown despite the strong medical impact that misjudging pain can have on patients' well-being. Methods Here, we investigated this question by applying the Bubbles method. Fifty healthy volunteers were asked to categorize facial expressions (the six basic emotions, pain and neutrality) displayed in stimuli obtained from a previously validated set and presented for 500 ms each. To determine the critical areas of the face used in this categorization task, the faces were partly masked based on random sampling of regions of the stimuli at different spatial frequency ranges. Results Results show that accurate pain discrimination relies mostly on the frown lines and the mouth. Finally, an ideal observer analysis indicated that the use of the frown lines in human observers could not be attributed to the objective 'informativeness' of this area. Conclusions Based on a recent study suggesting that this area codes for the affective dimension of pain, we propose that the visual system has evolved to focus primarily on the facial cues that signal the aversiveness of pain, consistent with the social role of facial expressions in the communication of potential threats. © 2015 European Pain Federation-EFIC®.
9.
Ouyed, O.; Allili, M. S.
Feature relevance for kernel logistic regression and application to action classification Article d'actes
Dans: Proceedings - International Conference on Pattern Recognition, p. 1325–1329, Institute of Electrical and Electronics Engineers Inc., 2014, ISBN: 978-1-4799-5208-3, (ISSN: 10514651).
Résumé | Liens | BibTeX | Étiquettes: Action classifications, Action recognition, Classification (of information), Classification methods, Classification performance, Feature relevance, Kernel logistic regression, Logistic regression, Multinomial kernels, Pattern Recognition, Supervised classification, Support vector machines
@inproceedings{ouyed_feature_2014,
title = {Feature relevance for kernel logistic regression and application to action classification},
author = {O. Ouyed and M. S. Allili},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84919884283&doi=10.1109%2fICPR.2014.237&partnerID=40&md5=616038cd7924614fd633061dfed32903},
doi = {10.1109/ICPR.2014.237},
isbn = {978-1-4799-5208-3},
year = {2014},
date = {2014-01-01},
booktitle = {Proceedings - International Conference on Pattern Recognition},
pages = {1325–1329},
publisher = {Institute of Electrical and Electronics Engineers Inc.},
abstract = {An approach is proposed for incorporating feature relevance in mutinomial kernel logistic regression (MKLR) for classification. MKLR is a supervised classification method designed for separating classes with non-linear boundaries. However, it assumes all features are equally important, which may decrease classification performance when dealing with high-dimensional or noisy data. We propose a feature weighting algorithm for MKLR which automatically tunes features contribution according to their relevance for classification and reduces data over-fitting. The proposed algorithm produces more interpretable models and is more generalizable than MKLR, Kernel-SVM and LASSO methods. Application to simulated data and video action classification has provided very promising results compared to the aforementioned classification methods. © 2014 IEEE.},
note = {ISSN: 10514651},
keywords = {Action classifications, Action recognition, Classification (of information), Classification methods, Classification performance, Feature relevance, Kernel logistic regression, Logistic regression, Multinomial kernels, Pattern Recognition, Supervised classification, Support vector machines},
pubstate = {published},
tppubtype = {inproceedings}
}
An approach is proposed for incorporating feature relevance in mutinomial kernel logistic regression (MKLR) for classification. MKLR is a supervised classification method designed for separating classes with non-linear boundaries. However, it assumes all features are equally important, which may decrease classification performance when dealing with high-dimensional or noisy data. We propose a feature weighting algorithm for MKLR which automatically tunes features contribution according to their relevance for classification and reduces data over-fitting. The proposed algorithm produces more interpretable models and is more generalizable than MKLR, Kernel-SVM and LASSO methods. Application to simulated data and video action classification has provided very promising results compared to the aforementioned classification methods. © 2014 IEEE.
10.
Blais, C.; Arguin, M.; Gosselin, F.
Human visual processing oscillates: Evidence from a classification image technique Article de journal
Dans: Cognition, vol. 128, no 3, p. 353–362, 2013, ISSN: 00100277.
Résumé | Liens | BibTeX | Étiquettes: amplitude modulation, article, Face, female, human, human experiment, Humans, male, normal human, oscillation, Oscillations, Pattern Recognition, Photic Stimulation, priority journal, reaction time, signal noise ratio, Signal-To-Noise Ratio, stimulus response, Temporal processing, vision, Visual, visual acuity, Visual Perception, Visual sampling, visual stimulation
@article{blais_human_2013,
title = {Human visual processing oscillates: Evidence from a classification image technique},
author = {C. Blais and M. Arguin and F. Gosselin},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84879014749&doi=10.1016%2fj.cognition.2013.04.009&partnerID=40&md5=c2d20982fa4a5c46b9d99d2912284ff6},
doi = {10.1016/j.cognition.2013.04.009},
issn = {00100277},
year = {2013},
date = {2013-01-01},
journal = {Cognition},
volume = {128},
number = {3},
pages = {353–362},
abstract = {Recent investigations have proposed that visual information may be sampled in a discrete manner, similarly to the snapshots of a camera, but this hypothesis remains controversial. Moreover, assuming a discrete sampling of information, the properties of this sampling-for instance, the frequency at which it operates, and how it synchronizes with the environment-still need to be clarified. We systematically modulated the signal-to-noise ratio of faces through time and examined how it impacted face identification performance. Altogether, our results support the hypothesis of discrete sampling. Furthermore, they suggest that this mechanism may operate at a rate of about 10-15. Hz and that it is synchronized with the onset of the stimulus. © 2013 Elsevier B.V.},
keywords = {amplitude modulation, article, Face, female, human, human experiment, Humans, male, normal human, oscillation, Oscillations, Pattern Recognition, Photic Stimulation, priority journal, reaction time, signal noise ratio, Signal-To-Noise Ratio, stimulus response, Temporal processing, vision, Visual, visual acuity, Visual Perception, Visual sampling, visual stimulation},
pubstate = {published},
tppubtype = {article}
}
Recent investigations have proposed that visual information may be sampled in a discrete manner, similarly to the snapshots of a camera, but this hypothesis remains controversial. Moreover, assuming a discrete sampling of information, the properties of this sampling-for instance, the frequency at which it operates, and how it synchronizes with the environment-still need to be clarified. We systematically modulated the signal-to-noise ratio of faces through time and examined how it impacted face identification performance. Altogether, our results support the hypothesis of discrete sampling. Furthermore, they suggest that this mechanism may operate at a rate of about 10-15. Hz and that it is synchronized with the onset of the stimulus. © 2013 Elsevier B.V.