Several neuroimaging studies have demonstrated amygdalar atrophy from the earliest stages of Alzheimers Disease (AD;e.g.Horinek, 2007).However, the level of atrophy compared with changes in amygdalar volume reported in healthy older adults and his behavioral consequences in patients remain largely unknown.In this study, we describe recent works from our group examining i/amygdalar volume loss, ii/amygdalar activity and behavioral correlates during emotional tasks in early AD patients to assess the clinical relevance of amygdala studies in early diagnosis of AD.We first examine in 100 AD patients whether changes in amygdalar volume are correlated to classical neuropsychological assessments.We compare then findings from neuroimaging and behavioural studies using a variety of emotional tasks, putative markers of the volume loss in amygdala.We discuss main results from our recent meta-analysis on emotional processing in AD, explaining inconsistencies in the ability of patients to process emotional information.In addition, we explore particularly in AD the promising hypothesis considering that the amygdala is differentially involved in implicit (automatic) and explicit (controlled) emotional processing.This hypothesis is supported by recent data suggesting that autonomic emotional relevance processing is selectively impaired, whereas compensatory mechanism are engaged in explicit emotional categorization tasks.With respect to the progressive atrophy of the amygdala in the dementia, we attempt to compile findings from our different approaches to unravel whether amygdalar changes constitute a promising biological marker of AD.