title: Evidence of improved immediate verbal memory and diminished category fluency following STN-DBS in Chinese-Cantonese patients with idiopathic Parkinson's disease.
abstract: The present study investigated the neuropsychological effects of bilateral deep brain stimulation (DBS) on subthalamic nucleus (STN) in Chinese-Cantonese patients with idiopathic Parkinson's disease (PD). Twenty-seven patients were prospectively recruited from the Movement Disorder Clinic at the Hong Kong Prince of Wales Hospital. Neuropsychological evaluations were performed at baseline, 6 and 12 months following the DBS procedure. Assessment battery included standardized tests on global cognitive function, verbal memory, non-verbal memory, confrontation naming, visuospatial organization, attention and executive functions. Anxiety and depressive symptoms were measured by two self-reported questionnaires. Results demonstrated diminished performance on a category fluency task that occurred at 6 months post-operatively and persisted at 12-month re-evaluation; 29.6-33.3 % of patients showed reduction of more than 1 SD (standard deviation) at post-operative measure. Conversely, performance on an immediate recall task in a verbal memory test was found to improve significantly at the same time point and persisted through 12 months after surgery; 22.2-25.9 % showed an improvement (≥1 SD). Psychologically, anxiety symptoms were statistically decreased and the significant reduction occurred at 12 months after surgery. Patients who reported a moderate to severe level of anxiety reduced from 51.9 to 18.5 %. Our findings concurred with most evidences on the effects of STN-DBS on verbal fluency; on the other hand, we demonstrated improvement of immediate verbal memory that warranted further investigation.
authors.affiliation: Department of Clinical Psychology, Prince of Wales Hospital, Hospital Authority, Shatin, Hong Kong, venustang@gmail.com.
authors.forename: Venus
authors.initials: V
authors.lastname: Tang
authors.forename: Cannon X L
authors.initials: CX
authors.lastname: Zhu
authors.forename: Danny
authors.initials: D
authors.lastname: Chan
authors.forename: Claire
authors.initials: C
authors.lastname: Lau
authors.forename: Anne
authors.initials: A
authors.lastname: Chan
authors.forename: Vincent
authors.initials: V
authors.lastname: Mok
authors.forename: Jonas
authors.initials: J
authors.lastname: Yeung
authors.forename: Wai Sang
authors.initials: WS
authors.lastname: Poon
mesh_terms: D000368:Aged; D044466:Asian People / Q000208:ethnology; D003072:Cognition Disorders / Q000209:etiology / Q000628:therapy*; D046690:Deep Brain Stimulation / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008569:Memory Disorders / Q000209:etiology / Q000628:therapy*; D008875:Middle Aged; D009483:Neuropsychological Tests; D010300:Parkinson Disease / Q000150:complications / Q000628:therapy; D018709:Statistics, Nonparametric; D020531:Subthalamic Nucleus / Q000502:physiology*; D014705:Verbal Behavior / Q000502:physiology*; D014706:Verbal Learning / Q000502:physiology*