title: White-matter changes correlate with cognitive functioning in Parkinson's disease.
abstract: Diffusion tensor imaging (DTI) findings from emerging studies of cortical white-matter integrity in Parkinson's disease (PD) without dementia are inconclusive. When white-matter changes have been found, their relationship to cognitive functioning in PD has not been carefully investigated. To better characterize changes in tissue diffusivity and to understand their functional significance, the present study conducted DTI in 25 PD patients without dementia and 26 controls of similar ages. An automated tract-based DTI method was used. Fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) were analyzed. Neuropsychological measures of executive functioning (working memory, verbal fluency, cognitive flexibility, inhibitory control) and visuospatial ability were then correlated with regions of interest that showed abnormal diffusivity in the PD group. We found widespread reductions in FA and increases in MD in the PD group relative to controls. These changes were predominantly related to an increase in RD. Increased AD in the PD group was limited to specific frontal tracks of the right hemisphere, possibly signifying more significant tissue changes. Motor symptom severity did not correlate with FA. However, different measures of executive functioning and visuospatial ability correlated with FA in different segments of tracts, which contain fiber pathways to cortical regions that are thought to support specific cognitive processes. The findings suggest that abnormal tissue diffusivity may be sensitive to subtle cognitive changes in PD, some of which may be prognostic of future cognitive decline.
authors: Department of Radiology, University of California San Diego La Jolla, CA, USA.
authors: Rebecca J
authors: RJ
authors: Theilmann
authors: Jason D
authors: JD
authors: Reed
authors: David D
authors: DD
authors: Song
authors: Mingxiong X
authors: MX
authors: Huang
authors: Roland R
authors: RR
authors: Lee
authors: Irene
authors: I
authors: Litvan
authors: Deborah L
authors: DL
authors: Harrington
keywords: Parkinson’s disease; cerebral cortex; cognition; diffusion tensor imaging; white-matter
references: Acta Neurol Scand. 2007 Sep;116(3):177-81
references: 17714331
references: Neuroimage. 2003 Nov;20(3):1714-22
references: 14642481
references: Magn Reson Imaging. 1999 Jul;17(6):881-92
references: 10402595
references: Neuroimage. 2011 Apr 15;55(4):1454-60
references: 21238597
references: Brain. 2012 Jul;135(Pt 7):2202-14
references: 22669082
references: Brain Stimul. 2013 Jan;6(1):16-24
references: 22410476
references: AJNR Am J Neuroradiol. 2008 Mar;29(3):501-5
references: 18202242
references: Brain. 1981 Jun;104(2):383-404
references: 6263406
references: Neuroscientist. 2004 Dec;10(6):525-37
references: 15534038
references: J Int Neuropsychol Soc. 2013 Mar;19(3):349-54
references: 23321049
references: J Neurosci. 2003 Jul 16;23(15):6351-6
references: 12867520
references: J Psychiatr Res. 1975 Nov;12(3):189-98
references: 1202204
references: Neuroimage. 2012 Feb 1;59(3):2831-8
references: 21982934
references: Hum Brain Mapp. 2003 Sep;20(1):29-40
references: 12953304
references: Hum Brain Mapp. 2014 Apr;35(4):1325-33
references: 23417856
references: J Cereb Blood Flow Metab. 2012 Aug;32(8):1609-17
references: 22569194
references: Lancet Neurol. 2010 Dec;9(12):1200-1213
references: 20880750
references: Neurobiol Dis. 2012 Jun;46(3):590-6
references: 22484304
references: Neuroimage. 2009 Jan 1;44(1):83-98
references: 18501637
references: Neuroimage. 2012 Sep;62(3):1675-84
references: 22713671
references: Mov Disord. 2011 Jan;26(1):6-17
references: 21322014
references: AJNR Am J Neuroradiol. 2008 Jun;29(6):1128-33
references: 18372415
references: Biophys J. 1994 Jan;66(1):259-67
references: 8130344
references: Neuroimage. 2007 Apr 1;35(2):467-77
references: 17258908
references: Mov Disord. 2012 Jan;27(1):90-7
references: 21850668
references: Hum Brain Mapp. 2012 Mar;33(3):727-39
references: 21495116
references: Neuroimage. 2005 May 15;26(1):132-40
references: 15862213
references: Cell Tissue Res. 2004 Oct;318(1):149-61
references: 15338271
references: AJNR Am J Neuroradiol. 2007 Feb;28(2):226-35
references: 17296985
references: Neuroimage. 2006 Jul 15;31(4):1487-505
references: 16624579
references: Psychiatry Res. 2011 Dec 30;194(3):363-371
references: 22078796
references: Mov Disord. 2010 Sep 15;25(12):1888-94
references: 20669268
references: Magn Reson Med. 2003 Nov;50(5):1077-88
references: 14587019
references: Neuroimage. 2007 Jan 1;34(1):144-55
references: 17070705
references: Trends Cogn Sci. 2008 May;12(5):193-200
references: 18403252
references: AJNR Am J Neuroradiol. 2012 May;33(5):890-5
references: 22241380
references: Parkinsonism Relat Disord. 2010 Sep;16(8):498-502
references: 20573537
references: Eur J Neurosci. 2004 Feb;19(3):755-60
references: 14984425
references: Arch Neurol. 2003 Mar;60(3):387-92
references: 12633150
references: Arch Neurol. 2004 Jan;61(1):97-102
references: 14732626
references: Acad Radiol. 2011 Feb;18(2):235-41
references: 21232687
references: J Neurol Neurosurg Psychiatry. 2004 Mar;75(3):481-4
references: 14966170
references: Neuroradiology. 2011 Jul;53(7):471-81
references: 20737142
references: Eur J Radiol. 2011 Feb;77(2):269-73
references: 19692193
references: Neuroimage. 2009 Oct 1;47(4):2083-9
references: 19539037
references: Hum Brain Mapp. 2002 Jan;15(1):1-25
references: 11747097
references: J Int Neuropsychol Soc. 2006 Nov;12(6):896-900
references: 17064451
references: Neuron. 2002 Jan 31;33(3):341-55
references: 11832223
references: Neuroimage. 2009 Aug 15;47(2):435-41
references: 19447183
references: Neuroimage. 2010 Jan 1;49(1):1099-107
references: 19632335
references: Acta Neurol Scand. 2007 Aug;116(2):108-12
references: 17661796
references: Brain. 2009 Nov;132(Pt 11):2958-69
references: 19812213
references: Neuroimage. 2009 Feb 15;44(4):1247-58
references: 19027860
references: Parkinsonism Relat Disord. 2012 Nov;18(9):1029-33
references: 22705126
references: Neuroimage. 2002 Nov;17(3):1429-36
references: 12414282
references: Nat Neurosci. 2008 Jan;11(1):103-7
references: 18066057
references: Neurobiol Aging. 2012 Jan;33(1):61-74
references: 20371138