title: Apathy in Parkinson's disease: an electrophysiological study.
abstract: In Parkinson's disease (PD), apathy (or loss of motivation) is frequent. Nevertheless, the contribution of attentional disorders to its genesis is still not clearly known. We want to determine the relation existing between apathy and attentional disorders by using P300a (or novelty P3) as a marker of the attentional process. The study included 25 patients (13 women and 12 men) with PD for whom we have determined the relationship between automatic attention (represented by P300a) and motor status, apathy, executive dysfunction, mental flexibility, inhibitory control, and depression/anxiety. We have found a correlation between the apathy score and amplitude of novelty P300 during the ON period and also a correlation of the apathy score with a decrease in amplitude of P300 during the OFF period. In a linear regression model, changes in the P300a predicted the severity of apathy independently of any other variable. We concluded firstly that the reduction in amplitude of the P300a wave was a neurophysiological marker of apathy in PD and secondly that apathy led to both dopaminergic denervation (mesolimbic) and nondopaminergic (dorsolateral prefrontal-subcortical) dysfunction.
authors.affiliation: Department of Neurology, CHU Poitiers, University of Poitiers, 2 rue de la Milétrie, 86021 Poitiers, France.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Mathis
authors.affiliation: Department of Neurology, CHU Poitiers, University of Poitiers, 2 rue de la Milétrie, 86021 Poitiers, France.
authors.forename: Jean-Philippe
authors.initials: JP
authors.lastname: Neau
authors.affiliation: Department of Neurology, CHU Poitiers, University of Poitiers, 2 rue de la Milétrie, 86021 Poitiers, France.
authors.forename: Claudette
authors.initials: C
authors.lastname: Pluchon
authors.affiliation: Department of Neurology, CHU Poitiers, University of Poitiers, 2 rue de la Milétrie, 86021 Poitiers, France.
authors.forename: Marie-Noëlle
authors.initials: MN
authors.lastname: Fargeau
authors.affiliation: Department of Neurology, CHU Poitiers, University of Poitiers, 2 rue de la Milétrie, 86021 Poitiers, France.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Karolewicz
authors.affiliation: Department of Neurology, CHU Poitiers, University of Poitiers, 2 rue de la Milétrie, 86021 Poitiers, France.
authors.forename: Anna
authors.initials: A
authors.lastname: Iljicsov
authors.affiliation: Department of Neurology, CHU Poitiers, University of Poitiers, 2 rue de la Milétrie, 86021 Poitiers, France.
authors.forename: Roger
authors.initials: R
authors.lastname: Gil