BACKGROUND: Tourette syndrome (TS) is a chronic neurodevelopmental disorder characterised by the presence of multiple motor and phonic tics. Recent brain imaging investigations with diffusion tensor imaging (DTI) techniques found reduced measures of connectivity in the corpus callosum of children with TS compared with healthy controls, thus raising the hypothesis that the reduced interhemispherical connectivity in TS reflects neural plasticity processes. METHODS: We assessed corpus callosum white-matter connectivity with fractional anisotropy (FA) index from magnetic resonance-DTI in two monozygotic twins (male sex; age 20) discordant for the diagnosis of TS. RESULTS: Both conventional morphological magnetic resonance images and fibre-tracking reconstruction failed to show any difference between the two twins. On the other hand, mean corpus callosum FA values were significantly lower in the affected twin than in the unaffected twin (p<0.01). The differences in FA values were highest in the posterior portions of the corpus callosum, and lowest in the central area. CONCLUSIONS: Our findings of reduced interhemispherical white-matter connectivity in the affected twin support the hypothesis that plastic remodelling in the corpus callosum possibly represents an adaptation mechanism in TS.
BACKGROUND:Tourette syndrome (TS) is a chronic neurodevelopmental disorder characterised by the presence of multiple motor and phonic tics. Recent brain imaging investigations with diffusion tensor imaging (DTI) techniques found reduced measures of connectivity in the corpus callosum of children with TS compared with healthy controls, thus raising the hypothesis that the reduced interhemispherical connectivity in TS reflects neural plasticity processes. METHODS: We assessed corpus callosum white-matter connectivity with fractional anisotropy (FA) index from magnetic resonance-DTI in two monozygotic twins (male sex; age 20) discordant for the diagnosis of TS. RESULTS: Both conventional morphological magnetic resonance images and fibre-tracking reconstruction failed to show any difference between the two twins. On the other hand, mean corpus callosum FA values were significantly lower in the affected twin than in the unaffected twin (p<0.01). The differences in FA values were highest in the posterior portions of the corpus callosum, and lowest in the central area. CONCLUSIONS: Our findings of reduced interhemispherical white-matter connectivity in the affected twin support the hypothesis that plastic remodelling in the corpus callosum possibly represents an adaptation mechanism in TS.
Authors: Julia Lubsen; Betty Vohr; Eliza Myers; Michelle Hampson; Cheryl Lacadie; Karen C Schneider; Karol H Katz; R Todd Constable; Laura R Ment Journal: Semin Perinatol Date: 2011-02 Impact factor: 3.300
Authors: Luolan Li; Cecile L Maire; Misha Bilenky; Annaïck Carles; Alireza Heravi-Moussavi; Chibo Hong; Angela Tam; Baljit Kamoh; Stephanie Cho; Dorothy Cheung; Irene Li; Tina Wong; Raman P Nagarajan; Andrew J Mungall; Richard Moore; Ting Wang; Claudia L Kleinman; Nada Jabado; Steven Jm Jones; Marco A Marra; Keith L Ligon; Joseph F Costello; Martin Hirst Journal: Epigenomics Date: 2020-07-17 Impact factor: 4.778