Neuronal nicotinic acetylcholine receptors (nAChRs) are critical for higher 
order cognitive processes. Post-mortem studies suggest reductions in nAChRs 
(particularly the alpha(4)beta(2) subtype) with ageing and in Alzheimer's 
disease (AD). This study aimed to; (1) quantify nAChR distribution in vivo with 
2-[18F]fluoro-A-85380 (2-FA) in 15 early AD patients compared to 14 age-matched, 
healthy controls (HC) and (2) correlate nAChR distribution with cognitive 
performance in both groups. All participants were non-smokers and underwent 
cognitive testing along with a dynamic PET scan after injection of 200 MBq of 
2-FA. Brain regional 2-FA binding was assessed through a simplified estimation 
of Distribution Volume (DV(S)). The AD group differed significantly from HC on 
all cognitive measures employed, with impairments on measures of attention, 
working memory, language, executive function, visuospatial ability, verbal 
learning and verbal memory (p<.05). Contrary to post-mortem data this study 
found no evidence of in vivo nAChR loss in early AD despite significant 
cognitive impairment. Furthermore, no correlation between nAChR and cognitive 
performance was found for either group. The findings of the current study 
suggest preservation of nAChRs early in AD supporting previous studies. It is 
possible that while the clinical 2-FA PET method described here may be 
insensitive in detecting changes in early AD, such changes may be detected in 
more advanced stages of the illness.