%0 Journal Article
%T New Thoughts on Thought Disorders in Parkinson's Disease: Review of Current Research Strategies and Challenges
%A Jennifer G. Goldman
%J Parkinson's Disease
%D 2011
%I Hindawi Publishing Corporation
%R 10.4061/2011/675630
%X Psychosis is a frequent nonmotor complication in Parkinson's disease (PD), characterized by a broad phenomenology and likely due to a variety of intrinsic (i.e., PD-related) and extrinsic factors. Safe and effective therapies are greatly needed as PD psychosis contributes significantly to morbidity, mortality, nursing home placement, and quality of life. Novel research strategies focused on understanding the pharmacology and pathophysiology of PD psychosis, utilizing translational research including animal models, genetics, and neuroimaging, and even looking beyond the dopamine system may further therapeutic advances. This review discusses new research strategies regarding the neurobiology and treatment of PD psychosis and several associated challenges. 1. Introduction Psychosis is a frequent nonmotor complication of ParkinsonĄ¯s disease (PD) [1¨C3]. Psychotic symptoms in PD manifest predominantly as hallucinations and delusions, although recently revised criteria for PD psychosis extend the spectrum to include illusions, a false sense of presence, hallucinations, and delusions [4]. These neuropsychiatric phenomena likely stem from a combination of drug-related (i.e., exogenous or extrinsic) factors and PD-related (i.e., endogenous or intrinsic) complications, although the exact pathophysiology of PD psychosis is unknown. Improved treatments for PD psychosis are greatly needed since hallucinations and delusions are important contributors to morbidity, mortality, nursing home placement, and quality of life [5¨C7]. To date, many clinical research trials for antipsychotic medications in PD have been affected by issues of trial design, medication side effects, and negative outcomes. As such, the goal of optimally designed clinical trials with effective and safe medications presents a challenge. Use of animal models or biomarkers (e.g., genetic or neuroimaging) may provide additional and complementary ways to advance treatments for PD psychosis. Thus, the aim of this review is to discuss new research strategies regarding PD psychosis and their associated challenges. This review will highlight research on nondopaminergic substrates, comorbid neuropsychiatric features often associated with PD psychosis and the potential roles for integrating in vivo neuroimaging, genetic risk factors, and animal models in studying PD psychosis, and lastly discuss challenges of medication trials. Dopaminergic medications have been well recognized to induce psychosis in PD by stimulating or inducing hypersensitivity of mesocorticolimbic dopamine receptors [8¨C10]. Virtually all
%U http://www.hindawi.com/journals/pd/2011/675630/