title: Worsening of Verbal Fluency After Deep Brain Stimulation in Parkinson's Disease: A Focused Review.
abstract: Worsening of verbal fluency after treatment with deep brain stimulation in Parkinson's disease patients is one of the most often reported cognitive adverse effect. The underlying mechanisms of this decline are not well understood. The present focused review assesses the evidence for the reliability of the often-reported decline of verbal fluency, as well as the evidence for the suggested mechanisms including disease progression, reduced medication levels, electrode positions, and stimulation effect vs. surgical effects. Finally, we highlight the need for more systematic investigations of the large degree of heterogeneity in the prevalence of verbal fluency worsening after DBS, as well as provide suggestions for future research.
authors.affiliation: Center of Functionally Integrative Neuroscience (CFIN), Dept. of Clinical Medicine, Aarhus University, Denmark.
authors.forename: Andreas
authors.initials: A
authors.lastname: Højlund
authors.affiliation: Center of Functionally Integrative Neuroscience (CFIN), Dept. of Clinical Medicine, Aarhus University, Denmark.
authors.forename: Mikkel V
authors.initials: MV
authors.lastname: Petersen
authors.affiliation: Center of Functionally Integrative Neuroscience (CFIN), Dept. of Clinical Medicine, Aarhus University, Denmark.
authors.forename: Kousik Sarathy
authors.initials: KS
authors.lastname: Sridharan
authors.affiliation: Center of Functionally Integrative Neuroscience (CFIN), Dept. of Clinical Medicine, Aarhus University, Denmark.
authors.forename: Karen
authors.initials: K
authors.lastname: Østergaard
keywords: Deep brain stimulation; Parkinson's disease; Verbal fluency