AIF1 and dementia: In addition, the contention that motile microglia respond to pathology in a protective way is also supported by the finding that in participants without dementia, there is a negative relationship between tangles and the marker Iba1 (associated with absence of dementia and good cognition); and in the participants with dementia and Alzheimer’s pathology by a worse MMSE score related to tangles but not Iba1 expression.