Alterations in the inferior longitudinal fasciculus in autism and associations with visual processing: a diffusion-weighted MRI study / Bart BOETS in Molecular Autism, 9 (2018)  

Public ISBD [article]  inMolecular Autism > 9 (2018) . - 10p. Titre : Alterations in the inferior longitudinal fasciculus in autism and associations with visual processing: a diffusion-weighted MRI study Type de document : texte imprimé Auteurs : Bart BOETS, Auteur ; Lien VAN EYLEN, Auteur ; Kevin SITEK, Auteur ; Pieter MOORS, Auteur ; Ilse NOENS, Auteur ; Jean STEYAERT, Auteur ; Stefan SUNAERT, Auteur ; Johan WAGEMANS, Auteur Article en page(s) : 10p. Langues : Anglais (eng) Mots-clés : Autism spectrum disorder  Diffusion-weighted imaging  Inferior longitudinal fasciculus  Structural connectivity  Visual processing Index. décimale : PER Périodiques Résumé : Background: One of the most reported neural features of autism spectrum disorder (ASD) is the alteration of multiple long-range white matter fiber tracts, as assessed by diffusion-weighted imaging and indexed by reduced fractional anisotropy (FA). Recent methodological advances, however, have shown that this same pattern of reduced FA may be an artifact resulting from excessive head motion and poorer data quality and that aberrant structural connectivity in children with ASD is confined to the right inferior longitudinal fasciculus (ILF). This study aimed at replicating the observation of reduced FA along the right ILF in ASD, while controlling for group differences in head motion and data quality. In addition, we explored associations between reduced FA in the right ILF and quantitative ASD characteristics, and the involvement of the right ILF in visual processing, which is known to be altered in ASD. Method: Global probabilistic tractography was performed on diffusion-weighted imaging data of 17 adolescent boys with ASD and 17 typically developing boys, matched for age, performance IQ, handedness, and data quality. Four tasks were administered to measure various aspects of visual information processing, together with questionnaires assessing ASD characteristics. Group differences were examined and the neural data were integrated with previously published findings using Bayesian statistics to quantify evidence for replication and to pool data and thus increase statistical power. (Partial) correlations were calculated to investigate associations between measures. Results: The ASD group showed consistently reduced FA only in the right ILF and slower performance on the visual search task. Bayesian statistics pooling data across studies confirmed that group differences in FA were confined to the right ILF only, with the evidence for altered FA in the left ILF being indecisive. Lower FA in the right ILF tended to covary with slower visual search and a more fragmented part-oriented processing style. Individual differences in FA of the right ILF were not reliably associated with the severity of ASD traits after controlling for clinical status. Conclusion: Our findings support the growing evidence for reduced FA along a specific fiber tract in ASD, the right ILF. En ligne : http://dx.doi.org/10.1186/s13229-018-0188-6 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=354 [article] Alterations in the inferior longitudinal fasciculus in autism and associations with visual processing: a diffusion-weighted MRI study [texte imprimé] / Bart BOETS, Auteur ; Lien VAN EYLEN, Auteur ; Kevin SITEK, Auteur ; Pieter MOORS, Auteur ; Ilse NOENS, Auteur ; Jean STEYAERT, Auteur ; Stefan SUNAERT, Auteur ; Johan WAGEMANS, Auteur . - 10p. Langues : Anglais (eng) in Molecular Autism > 9 (2018) . - 10p. Mots-clés : Autism spectrum disorder  Diffusion-weighted imaging  Inferior longitudinal fasciculus  Structural connectivity  Visual processing Index. décimale : PER Périodiques Résumé : Background: One of the most reported neural features of autism spectrum disorder (ASD) is the alteration of multiple long-range white matter fiber tracts, as assessed by diffusion-weighted imaging and indexed by reduced fractional anisotropy (FA). Recent methodological advances, however, have shown that this same pattern of reduced FA may be an artifact resulting from excessive head motion and poorer data quality and that aberrant structural connectivity in children with ASD is confined to the right inferior longitudinal fasciculus (ILF). This study aimed at replicating the observation of reduced FA along the right ILF in ASD, while controlling for group differences in head motion and data quality. In addition, we explored associations between reduced FA in the right ILF and quantitative ASD characteristics, and the involvement of the right ILF in visual processing, which is known to be altered in ASD. Method: Global probabilistic tractography was performed on diffusion-weighted imaging data of 17 adolescent boys with ASD and 17 typically developing boys, matched for age, performance IQ, handedness, and data quality. Four tasks were administered to measure various aspects of visual information processing, together with questionnaires assessing ASD characteristics. Group differences were examined and the neural data were integrated with previously published findings using Bayesian statistics to quantify evidence for replication and to pool data and thus increase statistical power. (Partial) correlations were calculated to investigate associations between measures. Results: The ASD group showed consistently reduced FA only in the right ILF and slower performance on the visual search task. Bayesian statistics pooling data across studies confirmed that group differences in FA were confined to the right ILF only, with the evidence for altered FA in the left ILF being indecisive. Lower FA in the right ILF tended to covary with slower visual search and a more fragmented part-oriented processing style. Individual differences in FA of the right ILF were not reliably associated with the severity of ASD traits after controlling for clinical status. Conclusion: Our findings support the growing evidence for reduced FA along a specific fiber tract in ASD, the right ILF. En ligne : http://dx.doi.org/10.1186/s13229-018-0188-6 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=354

Combined frequency-tagging EEG and eye-tracking measures provide no support for the "excess mouth/diminished eye attention" hypothesis in autism / Sofie VETTORI in Molecular Autism, 11 (2020)  

Public ISBD [article]  inMolecular Autism > 11 (2020) Titre : Combined frequency-tagging EEG and eye-tracking measures provide no support for the "excess mouth/diminished eye attention" hypothesis in autism Type de document : texte imprimé Auteurs : Sofie VETTORI, Auteur ; Stephanie VAN DER DONCK, Auteur ; Jannes NYS, Auteur ; Pieter MOORS, Auteur ; Tim VAN WESEMAEL, Auteur ; Jean STEYAERT, Auteur ; Bruno ROSSION, Auteur ; Milena DZHELYOVA, Auteur ; Bart BOETS, Auteur Langues : Anglais (eng) Index. décimale : PER Périodiques Résumé : BACKGROUND: Scanning faces is important for social interactions. Difficulty with the social use of eye contact constitutes one of the clinical symptoms of autism spectrum disorder (ASD). It has been suggested that individuals with ASD look less at the eyes and more at the mouth than typically developing (TD) individuals, possibly due to gaze aversion or gaze indifference. However, eye-tracking evidence for this hypothesis is mixed. While gaze patterns convey information about overt orienting processes, it is unclear how this is manifested at the neural level and how relative covert attention to the eyes and mouth of faces might be affected in ASD. METHODS: We used frequency-tagging EEG in combination with eye tracking, while participants watched fast flickering faces for 1-min stimulation sequences. The upper and lower halves of the faces were presented at 6 Hz and 7.5 Hz or vice versa in different stimulation sequences, allowing to objectively disentangle the neural saliency of the eyes versus mouth region of a perceived face. We tested 21 boys with ASD (8-12 years old) and 21 TD control boys, matched for age and IQ. RESULTS: Both groups looked longer at the eyes than the mouth, without any group difference in relative fixation duration to these features. TD boys looked significantly more to the nose, while the ASD boys looked more outside the face. EEG neural saliency data partly followed this pattern: neural responses to the upper or lower face half were not different between groups, but in the TD group, neural responses to the lower face halves were larger than responses to the upper part. Face exploration dynamics showed that TD individuals mostly maintained fixations within the same facial region, whereas individuals with ASD switched more often between the face parts. LIMITATIONS: Replication in large and independent samples may be needed to validate exploratory results. CONCLUSIONS: Combined eye-tracking and frequency-tagged neural responses show no support for the excess mouth/diminished eye gaze hypothesis in ASD. The more exploratory face scanning style observed in ASD might be related to their increased feature-based face processing style. En ligne : http://dx.doi.org/10.1186/s13229-020-00396-5 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=438 [article] Combined frequency-tagging EEG and eye-tracking measures provide no support for the "excess mouth/diminished eye attention" hypothesis in autism [texte imprimé] / Sofie VETTORI, Auteur ; Stephanie VAN DER DONCK, Auteur ; Jannes NYS, Auteur ; Pieter MOORS, Auteur ; Tim VAN WESEMAEL, Auteur ; Jean STEYAERT, Auteur ; Bruno ROSSION, Auteur ; Milena DZHELYOVA, Auteur ; Bart BOETS, Auteur. Langues : Anglais (eng) in Molecular Autism > 11 (2020) Index. décimale : PER Périodiques Résumé : BACKGROUND: Scanning faces is important for social interactions. Difficulty with the social use of eye contact constitutes one of the clinical symptoms of autism spectrum disorder (ASD). It has been suggested that individuals with ASD look less at the eyes and more at the mouth than typically developing (TD) individuals, possibly due to gaze aversion or gaze indifference. However, eye-tracking evidence for this hypothesis is mixed. While gaze patterns convey information about overt orienting processes, it is unclear how this is manifested at the neural level and how relative covert attention to the eyes and mouth of faces might be affected in ASD. METHODS: We used frequency-tagging EEG in combination with eye tracking, while participants watched fast flickering faces for 1-min stimulation sequences. The upper and lower halves of the faces were presented at 6 Hz and 7.5 Hz or vice versa in different stimulation sequences, allowing to objectively disentangle the neural saliency of the eyes versus mouth region of a perceived face. We tested 21 boys with ASD (8-12 years old) and 21 TD control boys, matched for age and IQ. RESULTS: Both groups looked longer at the eyes than the mouth, without any group difference in relative fixation duration to these features. TD boys looked significantly more to the nose, while the ASD boys looked more outside the face. EEG neural saliency data partly followed this pattern: neural responses to the upper or lower face half were not different between groups, but in the TD group, neural responses to the lower face halves were larger than responses to the upper part. Face exploration dynamics showed that TD individuals mostly maintained fixations within the same facial region, whereas individuals with ASD switched more often between the face parts. LIMITATIONS: Replication in large and independent samples may be needed to validate exploratory results. CONCLUSIONS: Combined eye-tracking and frequency-tagged neural responses show no support for the excess mouth/diminished eye gaze hypothesis in ASD. The more exploratory face scanning style observed in ASD might be related to their increased feature-based face processing style. En ligne : http://dx.doi.org/10.1186/s13229-020-00396-5 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=438

---

1 (1 - 2 / 2) Par page : 25 50 100 200