title: Subthalamic nucleus stimulation affects incentive salience attribution in Parkinson's disease.
abstract: Deep brain stimulation (DBS) of the subthalamic nucleus (STN) can induce nonmotor side effects such as behavioral and mood disturbances or body weight gain in Parkinson's disease (PD) patients. We hypothesized that some of these problems could be related to an altered attribution of incentive salience (ie, emotional relevance) to rewarding and aversive stimuli. Twenty PD patients (all men; mean age ± SD, 58.3 ± 6 years) in bilateral STN DBS switched ON and OFF conditions and 18 matched controls rated pictures selected from the International Affective Picture System according to emotional valence (unpleasantness/pleasantness) and arousal on 2 independent visual scales ranging from 1 to 9. Eighty-four pictures depicting primary rewarding (erotica and food) and aversive fearful (victims and threat) and neutral stimuli were selected for this study. In the STN DBS ON condition, the PD patients attributed lower valence scores to the aversive pictures compared with the OFF condition (P < .01) and compared with controls (P < .01). The difference between the OFF condition and controls was less pronounced (P < .05). Furthermore, postoperative weight gain correlated with arousal ratings from the food pictures in the STN DBS ON condition (P < .05 compensated for OFF condition). Our results suggest that STN DBS increases activation of the aversive motivational system so that more relevance is attributed to aversive fearful stimuli. In addition, STN DBS-related sensitivity to food reward stimuli cues might drive DBS-treated patients to higher food intake and subsequent weight gain.
authors.affiliation: Department of Neurology and Center of Clinical Neuroscience, Charles University in Prague, 1st Faculty of Medicine and General University Hospital, Prague, Czech Republic. tereza.serranova@gmail.com
authors.forename: Tereza
authors.initials: T
authors.lastname: Serranová
authors.forename: Robert
authors.initials: R
authors.lastname: Jech
authors.forename: Petr
authors.initials: P
authors.lastname: Dušek
authors.forename: Tomáš
authors.initials: T
authors.lastname: Sieger
authors.forename: Filip
authors.initials: F
authors.lastname: Růžička
authors.forename: Dušan
authors.initials: D
authors.lastname: Urgošík
authors.forename: Evžen
authors.initials: E
authors.lastname: Růžička
mesh_terms: D000368:Aged; D001835:Body Weight; D016022:Case-Control Studies; D046690:Deep Brain Stimulation / Q000009:adverse effects*; D004644:Emotions / Q000502:physiology; D006801:Humans; D008297:Male; D008609:Mental Status Schedule; D008875:Middle Aged; D019964:Mood Disorders / Q000209:etiology*; D009042:Motivation / Q000502:physiology*; D009483:Neuropsychological Tests; D010300:Parkinson Disease / Q000523:psychology* / Q000628:therapy*; D010775:Photic Stimulation; D013223:Statistics as Topic; D018709:Statistics, Nonparametric; D020531:Subthalamic Nucleus / Q000502:physiology*