title: Oculomotor Impairments in Developmental Dyspraxia.
abstract: Children with developmental dyspraxia (DD) express impairments in the acquisition of various motor skills and in the development of their social cognition abilities. Although the neural bases of this condition are not fully understood, they are thought to involve frontal cortical areas, subcortical structures, and the cerebellum. Although cerebellar dysfunction is typically difficult to assess and quantify using traditional neurophysiological methods, oculomotor analysis may provide insight into specific cerebellar patterns. The aim of the present study was to investigate, in dyspraxic and typically developing subjects, various oculomotor saccade tasks specifically designed to reveal frontal and cerebellar dysfunction. In addition to evidence supporting prefrontal dysfunction, our results revealed increased variability of saccade accuracy consistent with cerebellar impairments. Furthermore, we found that dyspraxic patients showed decreased velocities of non-visually guided saccades. A closer analysis revealed significant differences in saccade velocity profiles with slightly decreased maximum saccade velocities but markedly prolonged deceleration phases. We show that this pattern was not related to a decreased state of alertness but was suggestive of cerebellar dysfunction. However, the clear predominance of this pattern in non-visually guided saccades warrants alternative hypotheses. In light of previous experimental and anatomical studies, we propose that this unusual pattern may be a consequence of impaired connections between frontal areas and cerebellar oculomotor structures.
authors.affiliation: Service de Neurophysiologie Clinique, AP-HP, Hôpital de la Salpêtrière, Paris, France. bertrand.gaymard@gmail.com.|AP-HP, Hôpital de la Salpêtrière, 75651, Paris, France. bertrand.gaymard@gmail.com.
authors.forename: B
authors.initials: B
authors.lastname: Gaymard
authors.affiliation: AP-HP, Hôpital de la Salpêtrière, 75651, Paris, France.|Service de Psychiatrie de l'Enfant et de l'Adolescent, Paris, France.|Institut des Systèmes Intelligents et Robotiques, Université Pierre et Marie Curie, 1 place Jussieu, 75005, Paris, France.
authors.forename: M
authors.initials: M
authors.lastname: Giannitelli
authors.affiliation: AP-HP, Hôpital de la Salpêtrière, 75651, Paris, France.|Service d'Ophtalmologie, Paris, France.
authors.forename: G
authors.initials: G
authors.lastname: Challes
authors.affiliation: AP-HP, Hôpital de la Salpêtrière, 75651, Paris, France.|Sorbonne Universités, UPMC Univ Paris 06, Inserm, CNRS, UM 75, U 1127, UMR 7225, ICM, 75013, France, Paris.
authors.forename: S
authors.initials: S
authors.lastname: Rivaud-Péchoux
authors.affiliation: AP-HP, Hôpital de la Salpêtrière, 75651, Paris, France.|Service de Psychiatrie de l'Enfant et de l'Adolescent, Paris, France.
authors.forename: O
authors.initials: O
authors.lastname: Bonnot
authors.affiliation: AP-HP, Hôpital de la Salpêtrière, 75651, Paris, France.|Service de Psychiatrie de l'Enfant et de l'Adolescent, Paris, France.|Institut des Systèmes Intelligents et Robotiques, Université Pierre et Marie Curie, 1 place Jussieu, 75005, Paris, France.
authors.forename: D
authors.initials: D
authors.lastname: Cohen
authors.affiliation: AP-HP, Hôpital de la Salpêtrière, 75651, Paris, France.|Service de Psychiatrie de l'Enfant et de l'Adolescent, Paris, France.
authors.forename: J
authors.initials: J
authors.lastname: Xavier
mesh_terms: D000293:Adolescent; D001072:Apraxias / Q000150:complications / Q000503:physiopathology*; D001696:Biomechanical Phenomena; D002531:Cerebellum / Q000503:physiopathology; D015897:Comorbidity; D002658:Developmental Disabilities / Q000150:complications / Q000503:physiopathology*; D053483:Eye Movement Measurements; D005260:Female; D006801:Humans; D008297:Male; D008568:Memory; D010775:Photic Stimulation; D011930:Reaction Time; D012438:Saccades / Q000502:physiology; D014796:Visual Perception; D055815:Young Adult
keywords: Cerebellum; Developmental dyspraxia; Saccades; Skewness