title: White matter hyperintensities alter functional organization of the motor system.
abstract: Severe white matter hyperintensities (WMH) represent cerebral small vessel disease and predict functional decline in the elderly. We used fMRI to test if severe WMH impact on functional brain network organization even before clinical dysfunction. Thirty healthy right-handed/footed subjects (mean age, 67.8 ± 7.5 years) underwent clinical testing, structural MRI and fMRI at 3.0T involving repetitive right ankle and finger movements. Data were compared between individuals with absent or punctuate (n = 17) and early confluent or confluent (n = 13) WMH. Both groups did not differ in mobility or cognition data. On fMRI, subjects with severe WMH demonstrated excess activation in the pre-supplementary motor area (SMA), frontal, and occipital regions. Activation differences were noted with ankle movements only. Pre-SMA activation correlated with frontal WMH load for ankle but not finger movements. With simple ankle movements and no behavioral deficits, elderly subjects with severe WMH demonstrated pre-SMA activation, usually noted with complex tasks, as a function of frontal WMH load. This suggests compensatory activation related to disturbance of frontosubcortical circuits.
authors: Department of Neurology, Medical University of Graz, Graz, Austria.
authors: Patricia
authors: P
authors: Linortner
authors: Franz
authors: F
authors: Fazekas
authors: Reinhold
authors: R
authors: Schmidt
authors: Stefan
authors: S
authors: Ropele
authors: Barbara
authors: B
authors: Pendl
authors: Katja
authors: K
authors: Petrovic
authors: Marisa
authors: M
authors: Loitfelder
authors: Christa
authors: C
authors: Neuper
authors: Christian
authors: C
authors: Enzinger
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000842:Ankle / Q000503:physiopathology; D059345:Cerebral Small Vessel Diseases / Q000175:diagnosis* / Q000503:physiopathology*; D005260:Female; D005385:Fingers / Q000503:physiopathology; D005625:Frontal Lobe / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009044:Motor Cortex / Q000473:pathology* / Q000503:physiopathology; D009068:Movement; D009778:Occipital Lobe / Q000473:pathology / Q000503:physiopathology