3 recherche sur le mot-clé 'Optic-tectum'

A dynamical analysis of oscillatory responses in the optic tectum / Sergio NEUENSCHWANDER in Cognitive Brain Research, 1-3 (October 1993)

Public ISBD [article]  inCognitive Brain Research > 1-3 (October 1993) . - p.175-181 Titre : A dynamical analysis of oscillatory responses in the optic tectum Type de document : texte imprimé Auteurs : Sergio NEUENSCHWANDER, Auteur ; Jacques MARTINERIE, Auteur ; Bernard RENAULT, Auteur ; Fransisco J. VARELA, Auteur Année de publication : 1993 Article en page(s) : p.175-181 Langues : Anglais (eng) Mots-clés : Optic-tectum Oscillatory-response Local-field-potential Correlation-dimension Non-linear-forecasting Index. décimale : PER Périodiques Résumé : Multi-unit recordings from the optic tectum of an awake pigeon displaying oscillatory behavior evoked by visual stimulus are highly non-stationary and contain a broad band of frequencies under a time-window analysis. Here we extend these observations by a non-linear dynamical analysis of these oscillatory signals (local fields potentials) in successive epochs during background activity and visual responses. Two numerical estimates have been obtained from the original data every 200 ms: (1) correlation dimension and (2) non-linear forecasting of the trajectories. Results from eight different recording sites analyzed are consistent and indicate, in the average, an increase in complexity of the signal during the oscillatory periods. Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=781 [article] A dynamical analysis of oscillatory responses in the optic tectum [texte imprimé] / Sergio NEUENSCHWANDER, Auteur ; Jacques MARTINERIE, Auteur ; Bernard RENAULT, Auteur ; Fransisco J. VARELA, Auteur . - 1993 . - p.175-181. Langues : Anglais (eng) in Cognitive Brain Research > 1-3 (October 1993) . - p.175-181 Mots-clés : Optic-tectum Oscillatory-response Local-field-potential Correlation-dimension Non-linear-forecasting Index. décimale : PER Périodiques Résumé : Multi-unit recordings from the optic tectum of an awake pigeon displaying oscillatory behavior evoked by visual stimulus are highly non-stationary and contain a broad band of frequencies under a time-window analysis. Here we extend these observations by a non-linear dynamical analysis of these oscillatory signals (local fields potentials) in successive epochs during background activity and visual responses. Two numerical estimates have been obtained from the original data every 200 ms: (1) correlation dimension and (2) non-linear forecasting of the trajectories. Results from eight different recording sites analyzed are consistent and indicate, in the average, an increase in complexity of the signal during the oscillatory periods. Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=781

Electrophysiological evidence for selective impairment of optic flow perception in autism spectrum disorder / Takao YAMASAKI in Research in Autism Spectrum Disorders, 5-1 (January-March 2011)  

Public ISBD [article]  inResearch in Autism Spectrum Disorders > 5-1 (January-March 2011) . - p.400-407 Titre : Electrophysiological evidence for selective impairment of optic flow perception in autism spectrum disorder Type de document : texte imprimé Auteurs : Takao YAMASAKI, Auteur ; Yoko KAMIO, Auteur ; Shozo TOBIMATSU, Auteur ; Takako FUJITA, Auteur ; Katsuya OGATA, Auteur ; Yoshinobu GOTO, Auteur ; Shinji MUNETSUNA, Auteur Année de publication : 2011 Article en page(s) : p.400-407 Langues : Anglais (eng) Mots-clés : Autism-spectrum-disorder Coherent-motion-perception Optic-flow Dorso-dorsal-pathway Ventro-dorsal-pathway Event-related-potentials Index. décimale : PER Périodiques Résumé : People with autism spectrum disorder (ASD) often show inferior global motion performance with superior performance in detail form perception, suggesting dysfunction of the dorsal visual stream. To elucidate the neural basis of impaired global motion perception in ASD, we measured psychophysical threshold and visual event-related potentials (ERPs) with a 128-channel system in 12 ASD and 12 healthy control adults. Radial optic flow (OF) and horizontal motion (HO) were used as the visual stimuli. The former was related to the ventro-dorsal stream formed by the inferior parietal lobule, while the latter was conveyed from the dorso-dorsal stream formed by the superior parietal lobule. No significant group differences were observed in the motion thresholds for both OF and HO. N170 and P200 were elicited as major components of ERPs in both groups. However, the latencies of both components for OF but not HO were significantly prolonged in ASD compared with the control group. Our ERP results suggest that ASD has a selective impairment for OF processing even though the psychophysical thresholds are preserved. Therefore, we provide the first electrophysiological evidence for altered function of the higher-level dorsal visual stream in ASD, specifically the ventro-dorsal stream closely related to OF perception. En ligne : http://dx.doi.org/10.1016/j.rasd.2010.06.002 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=111 [article] Electrophysiological evidence for selective impairment of optic flow perception in autism spectrum disorder [texte imprimé] / Takao YAMASAKI, Auteur ; Yoko KAMIO, Auteur ; Shozo TOBIMATSU, Auteur ; Takako FUJITA, Auteur ; Katsuya OGATA, Auteur ; Yoshinobu GOTO, Auteur ; Shinji MUNETSUNA, Auteur . - 2011 . - p.400-407. Langues : Anglais (eng) in Research in Autism Spectrum Disorders > 5-1 (January-March 2011) . - p.400-407 Mots-clés : Autism-spectrum-disorder Coherent-motion-perception Optic-flow Dorso-dorsal-pathway Ventro-dorsal-pathway Event-related-potentials Index. décimale : PER Périodiques Résumé : People with autism spectrum disorder (ASD) often show inferior global motion performance with superior performance in detail form perception, suggesting dysfunction of the dorsal visual stream. To elucidate the neural basis of impaired global motion perception in ASD, we measured psychophysical threshold and visual event-related potentials (ERPs) with a 128-channel system in 12 ASD and 12 healthy control adults. Radial optic flow (OF) and horizontal motion (HO) were used as the visual stimuli. The former was related to the ventro-dorsal stream formed by the inferior parietal lobule, while the latter was conveyed from the dorso-dorsal stream formed by the superior parietal lobule. No significant group differences were observed in the motion thresholds for both OF and HO. N170 and P200 were elicited as major components of ERPs in both groups. However, the latencies of both components for OF but not HO were significantly prolonged in ASD compared with the control group. Our ERP results suggest that ASD has a selective impairment for OF processing even though the psychophysical thresholds are preserved. Therefore, we provide the first electrophysiological evidence for altered function of the higher-level dorsal visual stream in ASD, specifically the ventro-dorsal stream closely related to OF perception. En ligne : http://dx.doi.org/10.1016/j.rasd.2010.06.002 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=111

Fundus Peripapillary Vascular Changes in Autism Spectrum Disorder: A Cross-Sectional Study / Yuexuan WANG in Autism Research, 18-9 (September 2025)  

Public ISBD [article]  inAutism Research > 18-9 (September 2025) . - p.1775-1795 Titre : Fundus Peripapillary Vascular Changes in Autism Spectrum Disorder: A Cross-Sectional Study Type de document : texte imprimé Auteurs : Yuexuan WANG, Auteur ; Yonglu WANG, Auteur ; Zhaoqi ZHU, Auteur ; Zhengwang XIA, Auteur ; Ningyu WANG, Auteur ; Mingchao LI, Auteur ; Ziyun JIAO, Auteur ; Nairong PAN, Auteur ; Youqiang ZHANG, Auteur ; Qiang CHEN, Auteur ; Xiaoyan KE, Auteur ; Weiwei ZHANG, Auteur Article en page(s) : p.1775-1795 Langues : Anglais (eng) Mots-clés : angiography  autism spectrum disorder  functional magnetic resonance imaging  interdisciplinary understanding  optic disc  optical coherence tomography  retinal vasculature Index. décimale : PER Périodiques Résumé : ABSTRACT In this cross-sectional study, participants were recruited through convenience sampling from the Children's Mental Health Research Center at The Affiliated Brain Hospital of Nanjing Medical University and the Department of Ophthalmology at The First Affiliated Hospital of Nanjing Medical University, Nanjing, China, between December 2019 and October 2024. A total of 200 eyes were ultimately enrolled in this study, sourced from 53 individuals with ASD, aged between 7 and 13 years, and an equal number of age- and sex-matched neurotypical (NT) controls. The aim of this research is to explore the changes in retinal and choroidal vasculature in children with ASD, evaluated through optical coherence tomography and its angiography, and to further investigate the potential value of retinal vascular characteristics in the auxiliary screening and diagnosis of ASD. We analyzed intergroup differences in perfusion density (PD), vessel density, flux index (FI), fractal dimension (FD), and vessel diameter (Dm) in the peripapillary region, further stratified by subquadrants and vessel types. The results show that ASD children exhibited significant differences compared to neurotypical controls, including increased PD and Dm in the supero-nasal quadrant (p=0.01), changes in capillary FI in the nasal quadrant (p=0.008), increased venous FD (p=0.009), and abnormal choroidal FI in the temporal quadrant (p=0.008). A random forest classification model constructed based on these key features demonstrated promising performance (AUC=0.7853) in distinguishing ASD from NT individuals, highlighting the potential of retinal vascular characteristics for auxiliary ASD screening. Moreover, retinal vascular parameters were significantly correlated (p=0.01) with blood oxygen level-dependent signals from functional magnetic resonance imaging in several brain regions, such as the amygdala (p=0.004 0.009) and temporal lobe (p=0.000 0.009). Further stepwise regression analysis indicates that key retinal vascular characteristics could partially predict core clinical features of ASD, such as social functioning (adjusted R 2 =0.091 0.104, quantified by total and subscale scores of Social Responsiveness Scale) and cognitive ability (adjusted R 2 =0.2785, quantified by total intelligence quotient scores). This study underscores the potential of retinal vascular features as biomarkers for ASD and provides a basis for future research on non-invasive retinal imaging-based approaches for ASD screening and diagnosis, while offering new perspectives for understanding the pathological mechanisms and clinical applications of ASD. En ligne : https://doi.org/10.1002/aur.70094 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=568 [article] Fundus Peripapillary Vascular Changes in Autism Spectrum Disorder: A Cross-Sectional Study [texte imprimé] / Yuexuan WANG, Auteur ; Yonglu WANG, Auteur ; Zhaoqi ZHU, Auteur ; Zhengwang XIA, Auteur ; Ningyu WANG, Auteur ; Mingchao LI, Auteur ; Ziyun JIAO, Auteur ; Nairong PAN, Auteur ; Youqiang ZHANG, Auteur ; Qiang CHEN, Auteur ; Xiaoyan KE, Auteur ; Weiwei ZHANG, Auteur . - p.1775-1795. Langues : Anglais (eng) in Autism Research > 18-9 (September 2025) . - p.1775-1795 Mots-clés : angiography  autism spectrum disorder  functional magnetic resonance imaging  interdisciplinary understanding  optic disc  optical coherence tomography  retinal vasculature Index. décimale : PER Périodiques Résumé : ABSTRACT In this cross-sectional study, participants were recruited through convenience sampling from the Children's Mental Health Research Center at The Affiliated Brain Hospital of Nanjing Medical University and the Department of Ophthalmology at The First Affiliated Hospital of Nanjing Medical University, Nanjing, China, between December 2019 and October 2024. A total of 200 eyes were ultimately enrolled in this study, sourced from 53 individuals with ASD, aged between 7 and 13 years, and an equal number of age- and sex-matched neurotypical (NT) controls. The aim of this research is to explore the changes in retinal and choroidal vasculature in children with ASD, evaluated through optical coherence tomography and its angiography, and to further investigate the potential value of retinal vascular characteristics in the auxiliary screening and diagnosis of ASD. We analyzed intergroup differences in perfusion density (PD), vessel density, flux index (FI), fractal dimension (FD), and vessel diameter (Dm) in the peripapillary region, further stratified by subquadrants and vessel types. The results show that ASD children exhibited significant differences compared to neurotypical controls, including increased PD and Dm in the supero-nasal quadrant (p=0.01), changes in capillary FI in the nasal quadrant (p=0.008), increased venous FD (p=0.009), and abnormal choroidal FI in the temporal quadrant (p=0.008). A random forest classification model constructed based on these key features demonstrated promising performance (AUC=0.7853) in distinguishing ASD from NT individuals, highlighting the potential of retinal vascular characteristics for auxiliary ASD screening. Moreover, retinal vascular parameters were significantly correlated (p=0.01) with blood oxygen level-dependent signals from functional magnetic resonance imaging in several brain regions, such as the amygdala (p=0.004 0.009) and temporal lobe (p=0.000 0.009). Further stepwise regression analysis indicates that key retinal vascular characteristics could partially predict core clinical features of ASD, such as social functioning (adjusted R 2 =0.091 0.104, quantified by total and subscale scores of Social Responsiveness Scale) and cognitive ability (adjusted R 2 =0.2785, quantified by total intelligence quotient scores). This study underscores the potential of retinal vascular features as biomarkers for ASD and provides a basis for future research on non-invasive retinal imaging-based approaches for ASD screening and diagnosis, while offering new perspectives for understanding the pathological mechanisms and clinical applications of ASD. En ligne : https://doi.org/10.1002/aur.70094 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=568