title: Successful Working Memory Processes and Cerebellum in an Elderly Sample: A Neuropsychological and fMRI Study.
abstract: BACKGROUND
  Imaging studies help to understand the evolution of key cognitive processes related to aging, such as working memory (WM). This study aimed to test three hypotheses in older adults. First, that the brain activation pattern associated to WM processes in elderly during successful low load tasks is located in posterior sensory and associative areas; second, that the prefrontal and parietal cortex and basal ganglia should be more active during high-demand tasks; third, that cerebellar activations are related to high-demand cognitive tasks and have a specific lateralization depending on the condition.
  
  
  METHODS
  We used a neuropsychological assessment with functional magnetic resonance imaging and a core N-back paradigm design that was maintained across the combination of four conditions of stimuli and two memory loads in a sample of twenty elderly subjects.
  
  
  RESULTS
  During low-loads, activations were located in the visual ventral network. In high loads, there was an involvement of the basal ganglia and cerebellum in addition to the frontal and parietal cortices. Moreover, we detected an executive control role of the cerebellum in a relatively symmetric fronto-parietal network. Nevertheless, this network showed a predominantly left lateralization in parietal regions associated presumably with an overuse of verbal storage strategies. The differential activations between conditions were stimuli-dependent and were located in sensory areas.
  
  
  CONCLUSIONS
  Successful WM processes in the elderly population are accompanied by an activation pattern that involves cerebellar regions working together with a fronto-parietal network.
authors.affiliation: Neuroimaging Laboratory, Division of Neurosciences, Center for Applied Medical Research (CIMA), University of Navarra, Pamplona, Spain.
authors.forename: Elkin O
authors.initials: EO
authors.lastname: Luis
authors.affiliation: Neuroimaging Laboratory, Division of Neurosciences, Center for Applied Medical Research (CIMA), University of Navarra, Pamplona, Spain; Department of Psychiatry, University of Cambridge, Cambridge, United Kingdom.
authors.forename: Gonzalo
authors.initials: G
authors.lastname: Arrondo
authors.affiliation: Neuroimaging Laboratory, Division of Neurosciences, Center for Applied Medical Research (CIMA), University of Navarra, Pamplona, Spain.
authors.forename: Marta
authors.initials: M
authors.lastname: Vidorreta
authors.affiliation: Neuroimaging Laboratory, Division of Neurosciences, Center for Applied Medical Research (CIMA), University of Navarra, Pamplona, Spain.
authors.forename: Martin
authors.initials: M
authors.lastname: Martínez
authors.affiliation: Neuroimaging Laboratory, Division of Neurosciences, Center for Applied Medical Research (CIMA), University of Navarra, Pamplona, Spain.
authors.forename: Francis
authors.initials: F
authors.lastname: Loayza
authors.affiliation: Neuroimaging Laboratory, Division of Neurosciences, Center for Applied Medical Research (CIMA), University of Navarra, Pamplona, Spain; CIBERNED, Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas, Instituto de Salud Carlos III, Madrid, Spain.
authors.forename: María A
authors.initials: MA
authors.lastname: Fernández-Seara
authors.affiliation: Neuroimaging Laboratory, Division of Neurosciences, Center for Applied Medical Research (CIMA), University of Navarra, Pamplona, Spain; Department of Neurology, Clínica Universidad de Navarra, University of Navarra School of Medicine, Pamplona, Spain; CIBERNED, Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas, Instituto de Salud Carlos III, Madrid, Spain.
authors.forename: María A
authors.initials: MA
authors.lastname: Pastor
mesh_terms: D000368:Aged; D000375:Aging / Q000523:psychology*; D001921:Brain / Q000502:physiology; D001931:Brain Mapping; D002531:Cerebellum / Q000502:physiology*; D005260:Female; D059907:Functional Neuroimaging; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D008875:Middle Aged; D009483:Neuropsychological Tests