A new integrative model of cerebral activation, deactivation and default mode function in Alzheimer’s disease

  • Marc Wermke
  • Christian Sorg
  • Afra M. Wohlschläger
  • Alexander Drzezga
Article

Abstract

Functional imaging methods such as positron emission tomography (PET) and functional magnetic resonance imaging (fMRI) allow in vivo assessment of cerebral metabolism at rest and cerebral responses to cognitive stimuli. Activation studies with different cognitive tasks have deepened the understanding of underlying pathology leading to Alzheimer disease (AD) and how the brain reacts to and potentially compensates the imposed damage inflicted by this disease. The aim of this manuscript study was to summarize current findings of activation studies in healthy people at risk for AD, in people with mild cognitive impairment (MCI) as a possible progenitor of AD and finally in patients with manifest AD, adding recent results about impaired deactivation abilities and default mode function in AD. A new comprehensive model will be introduced integrating these heterogeneous findings and explaining their impact on cognitive performance.

Keywords

Activation Deactivation Default mode Alzheimer’s disease Imaging 

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Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  • Marc Wermke
    • 1
    • 4
  • Christian Sorg
    • 2
  • Afra M. Wohlschläger
    • 3
  • Alexander Drzezga
    • 1
  1. 1.Department of Nuclear MedicineTechnische UniversitätMunichGermany
  2. 2.Department of Psychiatry and PsychotherapyTechnische UniversitätMunichGermany
  3. 3.Departments of Neuroradiology and NeurologyTechnische UniversitätMunichGermany
  4. 4.Nuklearmedizinische Klinik u. Poliklinik, Klinikum rechts der IsarTechnische Universität MünchenMünchenGermany

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