title: Social intentions in Parkinson's disease patients: A kinematic study.
abstract: Dysfunction of the dopaminergic system leads to motor, cognitive and motivational symptoms in brain disorders such as Parkinson's disease (PD). Moreover, the dopaminergic system plays an important role in social interactions. The dopaminergic input to the basal ganglia (BG) thought to integrate social cues during the planning and execution of voluntary movements remains, however, largely unexplored. Since PD provides a model to assess this function in humans, our study aimed to investigate the effects of social intentions on actions in non-demented PDpatients receiving dopamine replacement therapy (Levodopa = l-Dopa) and in neurologically healthy control participants. Patients' ability to modulate motor patterning depending on the intention motivating the action to be performed was evaluated both in "on" (with l-Dopa) and "off" (without l-Dopa) states. Participants were instructed to reach for and to grasp an object; they were then told to hand it to another person (social condition) or to place it on a concave frame (individual condition). A 'passive-observer' condition, which was similar to the 'individual' condition except for the presence of an onlooker who simply observed the scene, was also assessed to exclude the possibility that differences might be due to the presence of another person. Movement kinematics were recorded using a three-dimensional motion analysis system. Study results demonstrated that the controls and the PD patients in an 'on' state adopted different kinematic patterning for the 'social' and the 'individual' conditions; the PD patients in the 'off' state, instead, were unable to kinematically differentiate between the two conditions. These results suggest that l-Dopa treatment has positive effects on translating social intentions into specific motor patterns in PD patients.
authors: Dipartimento di Psicologia Generale, Università di Padova, Padova, Italy.
authors: Elisa
authors: E
authors: Straulino
authors: Unità Operativa di Neurologia Ospedale di Dolo USL13, Venezia, Italy.
authors: Tomaso
authors: T
authors: Scaravilli
authors: Dipartimento di Psicologia Generale, Università di Padova, Padova, Italy; Cognitive Neuroscience Center, University of Padova, Italy; Centro Linceo Interdisciplinare Beniamino Segre, Accademia dei Lincei, Roma, Italy. Electronic address: umberto.castiello@unipd.it.
authors: Umberto
authors: U
authors: Castiello
mesh_terms: D000978:Antiparkinson Agents / Q000627:therapeutic use; D001479:Basal Ganglia / Q000503:physiopathology; D001696:Biomechanical Phenomena; D016022:Case-Control Studies; D005260:Female; D018737:Hand Strength; D006801:Humans; D033182:Intention; D007398:Interpersonal Relations; D007980:Levodopa / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D009068:Movement; D010300:Parkinson Disease / Q000188:drug therapy / Q000503:physiopathology*; D011597:Psychomotor Performance; D012919:Social Behavior
chemical_list: D000978:Antiparkinson Agents; D007980:Levodopa
keywords: Basal ganglia; Dopamine; Motor intentions; Parkinson's disease; Reward; Social interactions