title: Effect of levodopa on both verbal and motor representations of action in Parkinson's disease: a fMRI study.
abstract: Previous studies have demonstrated that non-demented Parkinson's disease (PD) patients have a specific impairment of verb production compared with noun generation. One interpretation of this deficit suggested the influence of striato-frontal dysfunction on action-related verb processing. The aim of our study was to investigate cerebral changes after motor improvement due to dopaminergic medication on the neural circuitry supporting action representation in the brain as mediated by verb generation and motor imagery in PD patients. Functional magnetic resonance imaging on 8 PD patients in "ON" dopaminergic treatment state (DTS) and in "OFF" DTS was used to explore the brain activity during three different tasks: Object Naming (ObjN), Generation of Action Verbs (GenA) in which patients were asked to overtly say an action associated with a picture and mental simulation of action (MSoA) was investigated by asking subjects to mentally simulate an action related to a depicted object. The distribution of brain activities associated with these tasks whatever DTS was very similar to results of previous studies. The results showed that brain activity related to semantics of action is modified by dopaminergic treatment in PD patients. This cerebral reorganisation concerns mainly motor and premotor cortex suggesting an involvement of the putaminal motor loop according to the "motor" theory of verb processing.
authors: Inserm, Imagerie Cérébrale et Handicaps Neurologiques, UMR 825, 31059 Toulouse, France. patrice.peran@inserm.fr
authors: P
authors: P
authors: Péran
authors: F
authors: F
authors: Nemmi
authors: D
authors: D
authors: Méligne
authors: D
authors: D
authors: Cardebat
authors: A
authors: A
authors: Peppe
authors: O
authors: O
authors: Rascol
authors: C
authors: C
authors: Caltagirone
authors: J F
authors: JF
authors: Demonet
authors: U
authors: U
authors: Sabatini
mesh_terms: D000978:Antiparkinson Agents / Q000627:therapeutic use*; D001921:Brain / Q000187:drug effects* / Q000503:physiopathology; D006801:Humans; D007092:Imagination; D007980:Levodopa / Q000627:therapeutic use*; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D009043:Motor Activity / Q000187:drug effects / Q000502:physiology; D010300:Parkinson Disease / Q000188:drug therapy* / Q000503:physiopathology*; D011597:Psychomotor Performance / Q000187:drug effects / Q000502:physiology; D013060:Speech / Q000187:drug effects / Q000502:physiology
chemical_list: D000978:Antiparkinson Agents; D007980:Levodopa