Executive dysfunction in traumatic brain injury patients at risk for
Alzheimer's disorder 
   Lead Investigator:    Michelle Frankot
   Institution      :    West Virginia University
   E-Mail           :    mf0083@mix.wvu.edu
   Proposal ID      :    1573



   Proposal Description:
   1. There is mixed evidence in the current body of literature that traumatic  brain injury (TBI) can worsen symptoms of Alzheimer's disorder (AD). We have     designed a proposal to specifically assess executive function, a set of           higher-order functions (e.g., planning, adapting) mediated by the frontal lobe   of the brain, which is particularly relevant to TBI. We have developed two       specific goals (listed below) to explore the connection between TBI and           executive function in AD populations.                                             Goal 1: To determine the effects of TBI on objective measures of executive       function in elderly adults with cognitive impairment and healthy adults at risk  for AD. The effects of TBI on overall cognitive function and specific subtypes   of executive function (response inhibition, cognitive flexibility) will be       assessed in a sample of elderly patients with and without cognitive impairment.  For patients with cognitive impairment, we hypothesize that TBI will exacerbate  deficits on measures of executive function only. For healthy participants, we     predict TBI will interact with genotype to worsen executive function in           individuals with the ApoE4 allele. Although previous work found that one         subtype of executive function, response inhibition, was worsened on self-report  measures in a TBI/AD sample, these findings have not been corroborated with       objective neuropsychological measures. This is particularly problematic given     that other studies found TBI may not impact AD phenotype. The current project     will have sufficient power to resolve this question with data from several       thousand patients.                                                               Goal 2: To identify sociodemographic risk factors for psychiatric AD phenotype   among TBI patients. There is also mixed evidence that TBI worsens psychiatric     deficits in individuals at genetic risk for AD how