Cervical dystonia (CD) is a painful, disabling neurological condition involving involuntary contraction of neck muscles that twist/pull the head and is associated with impaired brain sensory-motor processing. Treatment involves injecting botulinum toxin type A (BoNT-A) every 3-months into the neck muscles causing these movements. There are 3 available BoNT-A formulations; Botox® and Xeomin® are used in our clinic. However, many patients experience short-lasting and sub-optimal effects as patients would prefer shorter injection cycles, which is not recommended in the product monographs. Dysport is another BoNT-A that is not widely used in Canada. Limited studies have suggested that Dysport may produce a better, longer lasting treatment response. Furthermore, the effects of Dysport compared to Botox/Xeomin in the brain have not been explored and could help Ipsen understand the superiority of Dysport for treating CD. This research proposes that Dysport has a longer treatment benefit compared to Botox/Xeomin by improving sensory-motor processing.