Sustained attention in cranial dystonia patients treated with botulinum toxin.

BACKGROUND: Primary cranial dystonia (PCD) is related to a functional disorder in basal ganglia usually accompanied by impaired executive function.

AIM: To investigate symptom relief and neurocognitive change in response to treatment with botulinum toxin (BTX) in a group of patients with PCD.

METHODS: We assessed nine patients with PCD and nine age- and educationally matched healthy individuals using tests of memory, sustained attention, span of auditory attention, and perceptual flexibility.

RESULTS: Despite well-preserved intellectual skills relative to controls, we identified a sustained attention deficit in patients with PCD. After BTX treatment, there was an increase in the scores of the concentration endurance test (sustained attention) and the values did not differ significantly from control group patients' scores.

CONCLUSION: The results support the view that executive dysfunction in PCD is secondary to the disrupting effects of the symptoms. Treatment with BTX alleviates the symptoms and, consequently, improves sustained attention.