1) Aarsland D, Bronnick K, Williams-Gray C, Weintraub D, Marder K, et al: Mild cognitive impairment in Parkinson disease: multicenter pooled analysis. Neurology 75: 1062-1069, 2010
2) Bodis-Wollner I: Neuropsychological and perceptual defects in Parkinson's disease. Parkinsonism Relat Disord 9: 83-89, 2003
3) Cummings JL: Frontal-subcortical circuits and human behavior. Arch Neurol 50: 873-880, 1993
4) Alexander GE, DeLong MR, Strick PL: Parallel organization of functionally segregated circuits linking basal ganglia and cortex. Annu Rev Neurosci 9: 357-381, 1986
5) Ogden JA, Growdon JH, Corkin S: Deficits on visuospatial tests involving forward planning in high-functioning Parkinsonians. Neuropsychiatry Neuropsychol Behav Neurol 3: 125-139, 1990
6) Kiernan RJ, Mueller J, Langston JW, Van Dyke C: The Neurobehavioral Cognitive Status Examination: a brief but differentiated approach to cognitive assessment. Ann Intern Med 107: 481-485, 1987
7) Gibb WR, Lees AJ: The relevance of the Lewy body to the pathogenesis of idiopathic Parkinson's disease. J Neurol Neurosurg Psychiatry 51: 745-752, 1988
8) Murakami H, Fujita K, Futamura A, Sugimoto A, Kobayakawa M, et al: The Montreal Cognitive Assessment and Neurobehavioral Cognitive Status Examination are useful for screening mild cognitive impairment in Japanese patients with Parkinson's disease. Neurol Clin Neurosci 1: 103-108, 2013
9) Tomlinson CL, Stowe R, Patel S, Rick C, Gray R, et al: Systematic review of levodopa dose equivalency reporting in Parkinson's disease. Mov Disord 25: 2649-2653, 2010
10) Dubois B, Burn D, Goetz C, Aarsland D, Brown RG, et al: Diagnostic procedures for Parkinson's disease dementia: recommendations from the movement disorder society task force. Mov Disord 22: 2314-2324, 2007
11) Riggeal BD, Crucian GP, Seignourel P, Jacobson CE, Okun MS, et al: Cognitive decline tracks motor progression and not disease duration in Parkinson patients. Neuropsychiatr Dis Treat 3: 955-958, 2007
12) Amboni M, Cozzolino A, Longo K, Picillo M, Barone P: Freezing of gait and executive functions in patients with Parkinson's disease. Mov Disord 23: 395-400, 2008
13) Nocera JR, Price C, Fernandez HH, Amano S, Vallabhajosula S, et al: Tests of dorsolateral frontal function correlate with objective tests of postural stability in early to moderate stage Parkinson's disease. Parkinsonism Relat Disord 16: 590-594, 2010
14) Groth-Marnat G, Teal M: Block design as a measure of everyday spatial ability: a study of ecological validity. Percept Mot Skills 90: 522-526, 2000
15) Garcia-Garcia D, Clavero P, Gasca Salas C, Lamet I, Arbizu J, et al: Posterior parietooccipital hypometabolism may differentiate mild cognitive impairment from dementia in Parkinson's disease. Eur J Nucl Med Mol Imaging 39: 1767-1777, 2012
16) Lazar RM, Weiner M, Wald HS, Kula RW: Visuoconstructive deficit following infarction in the right basal ganglia: a case report and some experimental data. Arch Clin Neuropsychol 10: 543-553, 1995
17) Waterston JA, Hawken MB, Tanyeri S, Jäntti P, Kennard C, et al: Influence of sensory manipulation on postural control in Parkinson's disease. J Neurol Neurosurg Psychiatry 56: 1276-1281, 1993
18) Christopher L, Koshimori Y, Lang AE, Criaud M, Strafella AP: Uncovering the role of the insula in non-motor symptoms of Parkinson's disease. Brain 137: 2143-2154, 2014