title: When I am (almost) 64: The effect of normal ageing on implicit motor imagery in young elderlies.
abstract: Motor imagery (M.I.) is a cognitive process in which movements are mentally evoked without overt actions. Behavioral and fMRI studies show a decline of explicit M.I. ability (e.g., the mental rehearsal of finger oppositions) with normal ageing: this decline is accompanied by the recruitment of additional cortical networks. However, none of these studies investigated behavioral and the related fMRI ageing modifications in implicit M.I. tasks, like the hand laterality task (HLT). To address this issue, we performed a behavioral and fMRI study: 27 younger subjects (mean age: 31 years) and 29 older subjects (mean age: 61 years) underwent two event-related design fMRI experiments. In the HLT, participants were asked to decide whether a hand rotated at different angles was a left or right hand. To test the specificity of any age related difference in the HLT, we used a letter rotation task as a control experiment: here subjects had to decide whether rotated letters were presented in a standard or a mirror orientation. We did not find any group difference in either behavioral task; however, we found significant additional neural activation in the elderly group in occipito-temporal regions: these differences were stronger for the HLT rather than for the LRT with group by task interactions effects in right occipital cortices. We interpret these results as evidence of compensatory processes associated with ageing that permit a behavioral performance comparable to that of younger subjects. This process appears to be more marked when the task specifically involves motor representations, even when these are implicitly evoked.
authors: fMRI Unit-IRCCS Galeazzi, Milan, Italy; Psychology Department & Milan Center for Neuroscience, University of Milano-Bicocca, Milan, Italy. Electronic address: laura.zapparoli@gmail.com.
authors: Laura
authors: L
authors: Zapparoli
authors: Psychology Department & Milan Center for Neuroscience, University of Milano-Bicocca, Milan, Italy.
authors: Gianluca
authors: G
authors: Saetta
authors: Psychology Department & Milan Center for Neuroscience, University of Milano-Bicocca, Milan, Italy.
authors: Carlo
authors: C
authors: De Santis
authors: Department of Brain and Behavioral Sciences, University of Pavia, Pavia, Italy.
authors: Martina
authors: M
authors: Gandola
authors: fMRI Unit-IRCCS Galeazzi, Milan, Italy.
authors: Alberto
authors: A
authors: Zerbi
authors: fMRI Unit-IRCCS Galeazzi, Milan, Italy; University Vita e Salute San Raffaele, Milan, Italy.
authors: Giuseppe
authors: G
authors: Banfi
authors: fMRI Unit-IRCCS Galeazzi, Milan, Italy; Psychology Department & Milan Center for Neuroscience, University of Milano-Bicocca, Milan, Italy.
authors: Eraldo
authors: E
authors: Paulesu
mesh_terms: D000328:Adult; D000375:Aging; D001921:Brain / Q000502:physiology*; D001931:Brain Mapping; D005260:Female; D006801:Humans; D007092:Imagination / Q000502:physiology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010364:Pattern Recognition, Visual / Q000502:physiology*
keywords: Ageing; Hand laterality task; Implicit motor imagery; fMRI