Functional Mri Activation of Inhibitory Control in Adolescents and Young Adults with Multiple Sclerosis

................................................................................................................................................... ii Acknowledgements ............................................................................................................................ iv Table of Contents .................................................................................................................................. v List of Tables ........................................................................................................................................ vii List of Figures ..................................................................................................................................... viii List of Abbreviations .......................................................................................................................... ix Introduction ............................................................................................................................................ 1 Overview of Multiple sclerosis ................................................................................................................... 2 Cognitive Impairment in Pediatric-­‐Onset Multiple Sclerosis ........................................................... 3 Relating brain damage to adaptive functional reorganization in patients with MS ................. 7 Attentional control and Response Inhibition ..................................................................................... 13 Purpose ................................................................................................................................................. 21 Objective 1. To examine response inhibition in pediatric-­‐onset MS patients and age-­‐ matched controls using a simple Go/No-­‐go task ............................................................................... 22 Objective 2. To evaluate the influence of age at disease onset and cerebral tissue damage on Go/No-­‐go performance parameters ................................................................................................ 22 Objective 3. To examine whether cognitively intact childhood-­‐onset MS patients produce a less efficient pattern of cerebral activation compared with age-­‐matched healthy controls ............................................................................................................................................................................ 22 Method ................................................................................................................................................... 23