Male and female subjects between 40-85 years old will be enrolled. Younger subjects are not included as the risk for brain amyloid lesions is too low
All subjects will speak English as their first language or demonstrate proficiency in English (defined as reaching a scaled score of > 11 on the WAIS vocabulary test).
All subjects will have normal cognition at baseline: a Clinical Dementia Rating CDR=0, Global Deterioration Scale GDS<2.
All subjects will be in good general health and able to participate in the LP and imaging exams. This determination is made by the study neurologist and reviewed at a consensus meeting for each subject.

NCT03663387_inc_T1
Person
Male
NCT03663387_inc_T2
Person
female
NCT03663387_inc_T3
Value
between 40-85 years
NCT03663387_inc_T4
Person
old
NCT03663387_inc_T6
Observation
speak English
NCT03663387_inc_T7
Qualifier
first language
NCT03663387_inc_T8
Observation
proficiency in English
NCT03663387_inc_T9
Measurement
WAIS vocabulary test
NCT03663387_inc_T10
Value
> 11
NCT03663387_inc_T11
Scope
> 11 on the WAIS vocabulary test
NCT03663387_inc_T12
Condition
normal cognition
NCT03663387_inc_T13
Temporal
at baseline
NCT03663387_inc_T14
Measurement
Clinical Dementia Rating CDR
NCT03663387_inc_T15
Value
=0
NCT03663387_inc_T16
Measurement
Global Deterioration Scale GDS
NCT03663387_inc_T17
Value
<2
NCT03663387_inc_T18
Condition
good general health
NCT03663387_inc_T19
Observation
able to participate
NCT03663387_inc_T20
Procedure
imaging exams
NCT03663387_inc_T21
Procedure
LP
NCT03663387_inc_T22
Scope
LP and imaging exams