Imaging of Cognition, Learning, and Memory in Aging
Condition: Alzheimer's Disease
MeSH terms: Alzheimer Disease
Study type: Observational

Summary: 
      This investigation is designed to study how the brain functions when it is performing
      explicit memory tasks, and furthermore how the brain systems supporting performance on these
      tests change as a function of aging. Implicit memory tasks may be distinguished from explicit
      memory tests in that explicit memory characterizes the directed or intentional recollection
      of previously learned information or events. In contrast, implicit (or nonconscious) memory
      is expressed in the facilitation of performance on some task or judgment on a stimulus owing
      to a prior presentation of that stimulus, without any necessary conscious awareness of the
      prior presentation. The investigators propose to use functional Magnetic resonance Imaging
      (fMRI) to measure brain activity during the performance of carefully designed explicit memory
      tasks. Comparison of brain activity during the different test conditions will provide
      information about the brain areas that are involved in mediating specific aspects of
      performance. Both older and younger individuals will be tested in order to understand age
      related changes in the brain activity. In order to examine the interactions between
      participants' differential levels of amyloid burden and their performance on cognitive tasks
      and fMRI neural activation, the investigators also propose PET imaging of older participants.
    

Detailed description: 
      The basic approach to measuring the brain activity associated with a given cognitive process
      (or processes) is as follows: It is known that increases in brain neuronal activity are
      associated with local increases in energy metabolism. Under normal circumstances, increases
      in brain metabolism lead to local changes in blood oxygenation in venules and larger veins.
      This change in blood oxygenation can be detected imaging methods which are sensitive to the
      differences in magnetic state between oxygenated and deoxygenated hemoglobin.

      The ultimate benefit of this research is to better understand how changes in both performance
      and the brain organization underlying that performance are affected by aging.
    

Intervention name(s): Florbetaben
Intervention type(s): Drug
Intervention description(s): This is a purely observational study. Results of the Florbetaben PET scan will be correlated with other observations.
Other intervention name(s): F-18 BAY
Observational model: Cohort
Time perspective: Cross-Sectional
Sampling method: Probability Sample
Study population: 
        Subjects will be recruited from ads placed in local newspapers and notices posted in the
        vicinity of Columbia University, the Columbia Presbyterian Medical Center, and in local
        senior centers that provide written consent for notice placement. We will also utilize a
        market mailing approach. Letters will be sent to appropriately aged potential subjects
        randomly selected from commercial lists. Additional elderly subjects will be recruited from
        the Sergievsky Joint Database. Informed consent will be elicited from all subjects.
      
Biospecimen description: 
      Whole blood (frozen)