title: Cognitive load results in motor overflow in essential tremor.
abstract: SK is an 84-year-old woman diagnosed with essential tremor (ET) but no cognitive deficits. In this experiment, we tested the effects of mental rotation (a form of additional cognitive load) during reaching behavior (with the right hand) on the tremor profile of the non-moving left hand. We observed a marked increase in tremor and its variability, as well as the "freezing" of the movement pattern as effects of the cognitive load. These findings imply cognitive-motor overlaps in patients with ET, raising the possibility that the deficits reflect the loss of a common pool of neural resources, despite the heterogeneity of the symptoms of the disorder.
authors.affiliation: a Department of Biomedical Sciences , Ohio University , Athens , OH , USA.
authors.forename: S Lee
authors.initials: SL
authors.lastname: Hong
authors.forename: Robert W
authors.initials: RW
authors.lastname: Isenhower
authors.forename: Jorge V
authors.initials: JV
authors.lastname: José
authors.forename: Elizabeth B
authors.initials: EB
authors.lastname: Torres
mesh_terms: D000369:Aged, 80 and over; D003071:Cognition / Q000502:physiology*; D020329:Essential Tremor / Q000523:psychology*; D005260:Female; D006801:Humans; D007092:Imagination / Q000502:physiology; D011597:Psychomotor Performance / Q000502:physiology; D012399:Rotation